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Publication
Journal: Molecules
October/12/2021
Abstract
Ordered mesoporous materials and their modification with multiple functional groups are of wide scientific interest for many applications involving interaction with biological systems and biomolecules (e.g., catalysis, separation, sensor design, nano-science or drug delivery). In particular, the immobilization of enzymes onto solid supports is highly attractive for industry and synthetic chemistry, as it allows the development of stable and cheap biocatalysts. In this context, we developed novel silylated amino acid derivatives (Si-AA-NH2) that have been immobilized onto SBA-15 materials in biocompatible conditions avoiding the use of toxic catalyst, solvents or reagents. The resulting amino acid-functionalized materials (SBA-15@AA) were characterized by XRD, TGA, EA, Zeta potential, nitrogen sorption and FT-IR. Differences of the physical properties (e.g., charges) were observed while the structural ones remained unchanged. The adsorption of the enzyme lysozyme (Lyz) onto the resulting functionalized SBA-15@AA materials was evaluated at different pHs. The presence of different functional groups compared with bare SBA-15 showed better adsorption results, for example, 79.6 nmol of Lyz adsorbed per m2 of SBA-15@Tyr compared with the 44.9 nmol/m2 of the bare SBA-15.
Keywords: SBA-15; lysozyme; protein adsorption; silylated amino acids; sol–gel.
Publication
Journal: Frontiers in Microbiology
October/21/2021
Abstract
Di-(2-ethylhexyl) phthalate (DEHP) is ubiquitously reported in global water bodies and exhibits various environmental and human health risks. However, the effects of DEHP chronic exposure on the intestinal microbiota and associated host health concerns in aquatic species are still largely unexplored. In this study, chronic exposure to DEHP at environmental levels significantly increased the body weight, length, and body mass index (BMI), especially in male fish. The microbial community was disrupted with the relative abundance of phylum Firmicutes and genera diversity for Prevotella-7, Deefgea, PeM15, Halomonas, Akkermansia, Chitinibacter, and Roseomonas, which are significantly activated in zebrafish after exposure to DEHP. The height of the gut villus, the thickness of muscularis layer, and the number of goblet cells per villus were significantly decreased, as well as showed differences between female and male zebrafish. Further, the levels of energy-related metabolites in gut tissues were increased, compared to the control group. The expression levels of immune-related genes (interleukin 8, il-8, also referred to as cxcl8a), microbial defense-related genes (lysozyme, lyz, interleukin 10, and il-10), and obesity-related genes (aquaporin 8a, aqp8, mucin 2.1, muc2.1, fibroblast growth factor 2, fgf2, and proopiomelanocortin a, pomca) were significantly up-regulated in zebrafish, except the down-regulated expressions of toll-like receptor-5 (tlr-5) and interleukin 1β (il-1β) in the females and pomca in the males, respectively. Importantly, Spearman's correlation analyses revealed that the levels of metabolites and gene expressions in the gut were closely related to the dominant microbial genera, such as Aeromonas, Deefgea, Akkermansia, PeM15, Mycobacterium, and Rhodobacter. Taken together, chronic exposure to DEHP at environmental levels disturbed bacterial composition accompanied by the altered expressions of intestinal metabolites and the critical immune and intestinal function-related genes, which provided novel insights into DEHP effects on perturbation of gut microbiota and metabolic homeostasis in zebrafish.
Keywords: DEHP; chronic exposure; gut microbiota; metabolic disturbance; zebrafish development.
Publication
Journal: Zhonghua lao dong wei sheng zhi ye bing za zhi = Zhonghua laodong weisheng zhiyebing zazhi = Chinese journal of industrial hygiene and occupational diseases
November/1/2021
Abstract
Objective: To identify the related genes of low-dose ionizing radiation on basis of association analysis of transcriptome and proteome data, and provide new clues for the molecular mechanism of low-dose radiation (LDR) effect. Methods: In March 2018, healthy human peripheral blood was used as materials for transcriptome sequencing and proteome analysis after exposure to radiation at 150 mGy (treatment group) and no radiation (control group) , with three samples in each group. The total RNA and protein were extracted and then correlation analysis of transcriptomic and proteomic were performed to determine LDR effect-related genes, and after that, the biological process and molecular function were analyzed. Results: A total of 486 genes and 266 proteins were identified differentially expressed between treatment group and control group, respectively. Twelve genes and related proteins were found correlated (P<0.05) . The overall correlation between quantitative protein and gene was low (rs=0.0034) , the differential gene with the same change trend was positively correlated with protein expression (rs=0.6786) , and the differential gene with the opposite change trend was negatively correlated with protein expression (rs=-0.1000) . Seven differentially expressed genes (DEGs) showed the same trend as proteins, among which FBXO7 and SNCA were up-regulated as well as ORM1, ORM2, HIST1H4J, HBZ and LYZ were down-regulated. Five DEGs showed the opposite trend as proteins, including SLC4A1, BCAM, C4B_2, KEL, TGM2 up-regulated in transcription level and down-regulated in protein expression level. These DEGs were involved in various biological processes such as immune system regulation, signal transduction, enzyme activity regulation, transmembrane transport, defense, transcription and DNA repair, which indicated their important roles in response to LDR in human peripheral blood. Conclusion: Twelve candidate genes related to LDR effect and their corresponding expressed proteins are screened by the correlation research of transcriptome and proteome data, which provides new clues for the further study of the mechanism of LDR effect.
目的: 通过转录组和蛋白组数据关联分析,筛选低剂量电离辐射效应相关基因,为低剂量辐射效应的分子机制研究提供新思路。 方法: 于2018年3月,以健康人外周血为样本,分为照射组(150 mGy)和对照组(0 mGy),每组3个样本。提取两组样本总RNA和蛋白,对转录组和蛋白组数据进行关联分析,确定低剂量电离辐射效应相关表达基因,并进行生物过程及分子功能等的分析。 结果: 照射组和对照组差异表达的基因、蛋白数量分别为486、266个,12个基因和蛋白关联(P<0.05)。定量蛋白和基因总体关联性低(rs=0.003 4),变化趋势相同的差异基因和蛋白表达呈正相关(rs=0.678 6),变化趋势相反的差异基因和蛋白表达呈负相关(rs=-0.100 0)。与差异蛋白表达趋势相同的差异基因有7个,其中FBXO7SNCA表达上调,ORM1ORM2HIST1H4JHBZLYZ表达下调;表达趋势相反的基因有5个,包括SLC4A1BCAMC4B_2KELTGM2,均在基因水平上调,蛋白水平下调。差异基因涉及免疫系统调节、信号转导、酶活性调节、跨膜运输、防御、转录和DNA修复等方面功能。 结论: 转录组和蛋白组数据关联研究筛选出12个低剂量电离辐射效应相关候选基因及其对应的表达蛋白,为深入研究低剂量辐射效应机制提供新线索。.
Keywords: Differentially expressed genes (DEGs); Genomics; Occupational exposure; Proteomics; Radiation effects.
Authors
Publication
Journal: Langmuir
October/31/2021
Abstract
Benefiting from the luxury functions of proteins, protein coatings have been extended to various applications, including tissue engineering scaffolds, drug delivery, antimicrobials, sensing and diagnostic equipment, food packaging, etc. Fast construction of protein coatings is always interesting to materials science and significant to industrialization. Here, we report a layer-by-layer (LbL) multilayer-constructed coating of tannic acid (TA) and lysozyme (Lyz), in which the secondary conformations of Lyz dominate the growth rate of the TA/Lyz coating. As well characterized by various techniques (quartz crystal microbalance with dissipation (QCM-D), circular dichroism (CD) spectra, Fourier transform infrared (FTIR) spectroscopy, atomic force microscopy (AFM), contact angle, etc.), TA-induced conformational transition of Lyz to α-helices occurs at pH 8 from other secondary structures (β-sheets, β-turns, and random coils), which leads to the very fast growth of TA/Lyz with a number of deposited bilayers, with thicknesses of more than 90 nm for six bilayers. In contrast to the leading conformation of α-helices at pH 8, Lyz displayed multiple conformations (α-helices, β-sheets, β-turns, and random coils) at pH 6, which resulted in coating thicknesses of less than 30 nm for six bilayers. By the addition of NaCl, Tween 20, and urea, we further confirmed that the secondary conformations of Lyz relied greatly on the interactions between TA and Lyz and dominated the growth rate of the multilayers. We believe that these findings will help to understand the transformation of secondary conformations by TA or other polyphenols and inspire a new route to quickly build protein coatings.
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Publication
Journal: Analytical and Bioanalytical Chemistry
November/2/2021
Abstract
This research proposed a replacement-type electrochemiluminescent (ECL) aptasensor for lysozyme (LYZ) detection at trace levels based on a full-electric modification electrode (FEMG) coupled to silica-coated Ru(bpy)32+/silver nanospheres (Ru/SNs@SiO2). The multi-walled carbon nanotubes-doped-thionine (MWCNTs/PTn) electropolymerized modified electrode was decorated with electrodeposited gold nanoparticles (GNs) to form the FEMG. Then, the FEMG was utilized as sensing substrates for the immobilization of the anti-lysozyme aptamer (LA); the stability and number of LA attaching onto the FEMG were dramatically increased. The ECL measurement was used to evaluate the hybridization reaction of LA and the Ru/SNs@SiO2 marked DNA probe, and it was noted as Ia. After the combination of the LA with the LYZ, the target-triggered replacement of the DNA probe was actualized and the ECL measurement descended to Ib. The ECL difference (ΔIECL = Ia - Ib) before and after the replacement event was utilized for quantitation of LYZ. As a result, the fabricated aptasensor with great sensitivity and specificity achieved a wide linear range (10 fM-10 pM) and a low limit of detection (5 fM). It obtained satisfactory recovery for the detection of LYZ in human serum, and the results were identified with the LYZ ELISA kit. Therefore, the proposed ECL sensor is expected to become a promising approach in the field of biomolecule detection.
Keywords: Aptasensor; Electrochemiluminescence; Lysozyme; Nanospheres; Replacement-type.
Publication
Journal: International Journal of Biological Macromolecules
January/29/2022
Abstract
The influence of complexation between porcine gastric mucin (PGM) and lysozyme (LYZ) solutions (pH⁓7.0) on their lubricating properties was studied at a hydrophobic self-mated polydimethylsiloxane (PDMS) tribopair. To this end, LYZ solutions with varying heating time, namely 1hr, 3hr-, and 6hr at 90 °C, as well as unheated LYZ solution, were prepared. The lubricating capability of PGM and LYZ solutions and also their mixtures was characterized using pin-on-disk tribometry. In parallel, to precisely investigate the interaction between PGM and LYZ solutions, an array of the well-known experiments including electrophoretic-dynamic light scattering, circular dichroism spectroscopy and optical waveguide light-mode spectroscopy were employed. These experiments were utilized to elucidate the key features e.g. zeta potential, hydrodynamic diameter, conformational structure and mass adsorption. The tribometry results indicated that both PGM and unheated LYZ solutions had poor lubricating properties in the boundary lubrication regime (sliding speed lower than 10 mm/s). Mixing PGM with unheated LYZ led to a slight decrease in the friction coefficient, but no desirable lubricity was observed. An optimum slippery characteristic was achieved by incorporating 1hr heated LYZ solution into PGM one. Excellent lubricity of PGM/1hr heated LYZ may stem from surface charge compensation, tenaciously compact aggregation, unique conformational structure and considerable mass adsorption onto PDMS. This finding revealed that a strong interaction between PGM and LYZ molecules and as a result, the promising lubricating capability of PGM/LYZ mixtures, can be administered by varying heat-treatment duration of LYZ proteins.
Keywords: Lysozyme; Porcine gastric mucin (PGM); Structural and physicochemical characterizations; Synergistic lubrication.
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Publication
Journal: Fish and Shellfish Immunology
January/28/2022
Abstract
The supplemental effect of Pyropia yezoensis enzymatic hydrolysate (PYE) in fish diet was evaluated in zebrafish (Danio rerio) model. A basal diet supplemented with PYE at 0, 0.1, 1.0 and 2.0% were fed to one-month old zebrafish for 6 weeks, its growth performance and immunity index were evaluated. The increase in weight gain was significantly higher when supplementary 1% PYE which shows a positive effect on growth performance of zebrafish. In addition, crude protein content of fish body was increased in all PYE supplemental groups. The innate immune responses and activity of digestive enzymes in zebrafish were enhanced with dietary supplementation of PYE additives. Compared with the control group, lysozyme (LYZ) and interleukin-10 (IL-10) content in zebrafish intestines were up-regulated in groups fed with 0.1% and 1% PYE. The mRNA expression levels of LYZ and IL-10 in zebrafish intestines were consistent with ELISA results. The content of tumor necrosis factor (TNF-α) reduced in 1% and 2% PYE groups. Furthermore, PYE down-regulated the relative abundance of pathogenic bacteria (Aeromonadaceae) and up-regulated the relative abundance of fish probiotics (Brevibacillus) in intestinal flora. The findings in this study indicated that PYE supplementation in diet could promote growth, improve immunity and regulate intestinal flora, which made PYE considered as an potential aquatic additive.
Keywords: Growth promotion; Immune regulation; Intestinal flora; Pyropia yezoensis; Zebrafish.
Publication
Journal: Biochemical and Biophysical Research Communications
January/29/2022
Abstract
Organoid cryopreservation method is one of key step in the organoid culture. We aimed to establish a simple and efficient cryopreservation method for mouse small intestinal organoids (MIOs) and colon organoids (MCOs) using various concentrations of cryoprotectant. Based on the theoretical simulation, we optimized the dimethyl sulfoxide (DMSO) concentration by pretreating the organoids with 5, 7.5, and 10% DMSO for 30 min at 4 °C to allow penetration into the organoids and evaluated their viability, proliferation, and function after cryopreservation. Gene expression in the MIOs and staining of lineage markers were examined real-time PCR. The organoids in the DMSO-treated groups as well as the control, expressed ChrgA, Ecad, Muc2, Lyz, villin, and Lgr5, and there are no significant. A forskolin-induced swelling assay for MIOs was performed to confirm normal cystic fibrosis transmembrane conductance regulator (CFTR) activity. Similar forskolin-induced swelling was observed in the DMSO-treated groups and the control. In addition, MCOs were transplanted into mouse colon for confirmation of regeneration therapy efficacy. Thawing organoids were cultured for two and four sequential passages after cryopreservation with 5% DMSO to confirm any changes in the gene expression of lineage markers after subculture. We developed a simple and efficient organoid freezing method using 5% DMSO with low potential toxicity and validated our findings with theoretical simulation.
Keywords: Cryopreservation; Dimethyl sulfoxide; Mouse intestinal organoids; Organoid; Regeneration medicine.
Publication
Journal: Journal of Proteomics
January/22/2022
Abstract
The avian egg perivitelline layer (PL) is a proteinaceous structure that encloses the egg yolk. It consists of the inner and the outer perivitelline layers (IPL and OPL, respectively) that are assumed to play distinct roles in bird reproduction. To gain insight into their respective function, we analyzed the proteome of IPL and OPL in chicken unfertilized eggs after mechanical separation, using a GeLC-MS/MS strategy. Of the 412 proteins identified, 173 proteins were uniquely recovered in IPL and 98 proteins in OPL, while 141 proteins were identified in both sublayers. Genes coding the most abundant proteins were shown to be expressed either in the liver/ovary (IPL formation) or in the oviduct (OPL formation), but rarely in both. The presence of oviduct-specific proteins (including LYZ, VMO1, AvBD11, PTN, OVAL and LOC10175704) in IPL strongly suggests that they participate in the physical association of IPL to OPL, whose tight attachment was further evidenced by analyses of IPL/OPL interfaces (by scanning electron microscopy). Functional annotation of identified proteins revealed functions associated with fertilization and early development for IPL, while OPL would rather participate in egg defense and embryogenesis. Collectively, our data highlight the complementary functions of IPL and OPL that are major determinants of bird reproductive success. SIGNIFICANCE: The present study unveils for the first time the individual proteomes of the two sublayers composing the chicken egg perivitelline layer (PL), which allowed to assign their respective putative biological roles in avian reproduction. The combination of proteomics with gene expression and ultrastructural analyses provides insightful data on the structure and biochemistry of the avian PL. The functional annotation of PL proteins highlights the multifaceted biological functions of this structure in reproduction including fertilization, embryonic development, and antimicrobial protection. This work will stimulate further research to validate predicted functions and to compare the physiology and the functional specificities of PL in egg-laying species.
Keywords: Avian reproduction; Chicken; Egg; Functional annotation; Gallus gallus; Gene expression; Inner perivitelline layer; Outer perivitelline layer; Proteomics; Ultrastructure.
Publication
Journal: Science of the Total Environment
January/19/2022
Abstract
Phenanthrene (PHE) is a harmful organic contaminant and exists extensively in the soil environment. The accumulation of PHE would potentially threaten soil invertebrates, including earthworms, and the toxicity is also high. Currently, the possible mechanisms underlying apoptotic pathways induced by PHE and its immunotoxicity and genotoxicity in earthworms remain unclear. Thus, Eisenia fetida coelomocytes and immunity protein lysozyme (LYZ) were chosen as targeted receptors to reveal the apoptotic pathways, genotoxicity, and immunotoxicity triggered by PHE and its binding mechanism with LYZ, using cellular, biochemical, and molecular methods. Results indicated that PHE exposure can cause cell membrane damage, increase cell membrane permeability, and ultimately trigger mitochondria-mediated apoptosis. Increased 8-hydroxy-2-deoxyguanosine (8-OHdG) levels indicated PHE had triggered DNA oxidative damage in cells after PHE exposure. Occurrence of detrimental effects on the immune system in E. fetida coelomocytes due to decreased phagocytic efficacy and destroyed the lysosomal membrane. The LYZ activity in coelomocytes after PHE exposure was consistent with the molecular results, in which the LYZ activity was inhibited. After PHE binding, the protein structure (secondary structure and protein skeleton) and protein environment (the micro-environment of aromatic amino acids) of LYZ were destroyed, forming a larger particle size of the PHE-LYZ complex, and causing a significant sensitization effect on LYZ fluorescence. Molecular simulation indicated the key residues Glu 35, Asp 52, and Trp 62 for protein function located in the binding pocket, suggesting PHE preferentially binds to the active center of LYZ. Additionally, the primary driving forces for the binding interaction between PHE and LYZ molecule are hydrophobicity forces and hydrogen bonds. Taken together, PHE exposure can induce apoptosis by mitochondria-mediated pathway, destroy the normal immune system, and trigger DNA oxidative damage in earthworms. Besides, this study provides a comprehensive evaluation of phenanthrene toxicity to earthworms on molecular and cellular level.
Keywords: Cell apoptosis; DNA damage; Immunotoxicity; Interaction mechanism; Molecular simulation; Phenanthrene.
Publication
Journal: Medicine
January/19/2022
Abstract
To better understand the molecular mechanism underlying the pathogenesis of multiple sclerosis (MS), we aimed to identify the key genes and microRNAs (miRNA) associated with MS and analyze their interactions. Differentially expressed genes (DEGs) and miRNAs (DEMs) based on the gene miRNA dataset GSE17846 and mRNA dataset GSE21942 were determined using R software. Next, we performed functional enrichment analysis and constructed a protein-protein interaction network. Data validation was performed to ensure the reliability of hub genes. The miRNA-mRNA regulatory network was constructed. In total, 47 DEMs and 843 DEGs were identified. Protein-protein interaction network analysis identified several hub genes, including JUN, FPR2, AKT1, POLR2L, LYZ, CXCL8, HBB, CST3, CTSZ, and MMP9, especially LYZ and CXCL8. We constructed an miRNA-mRNA regulatory network and found that hsa-miR-142-3p, hsa-miR-107, hsa-miR-140-5p, and hsa-miR-613 were the most important miRNAs. This study reveals some key genes and miRNAs that may be involved in the pathogenesis of MS, providing potential targets for the diagnosis and treatment of MS.
Publication
Journal: Fish and Shellfish Immunology
January/19/2022
Abstract
The effect of four level of Astragalus polysaccharides (APs) supplementation diets, (CD: control diet and three experiment diet (E), EA: 100 mg kg-1 APs; EB: 200 mg kg-1 APs; EC: 300 mg kg-1 APs) on growth, changes in haemato-biochemical parameters and metabolic-digestive enzymes, enhancement of antioxidant activity, innate-adaptive immune response, and cytokine gene expression were studied in catla (Catla catla) against Edwardsiella tarda. The healthy and challenged groups fed the CD displayed no mortality, while fish fed EA or EC revealed 10% mortality, but the mortality was only 5% in diet EB. Fish fed diet EB and EC revealed significantly better growth rates and high RBC count during the experimental period. Albumin and globulin levels were significant improved when fish were fed the diet EB and EC from weeks 6-8. The superoxide dismutase (SOD) was significant ameliorated by EB feeding from weeks 4-8. In contrast, serum myeloperoxidase (MPO), catalase (CAT), malondialdehyde (MDA)/lipid peroxidation (LPO), glutathione peroxidase (GPx), respiratory burst activity (RBA), bactericidal action (BCA), serum lysozyme activity (SLA), nitric oxide synthase (NOS), head kidney leukocytes response proliferation (HKLP), hemolytic action (HLA), hydrogen peroxides (H2O2), and immunoglobulin (Ig) were significantly improved from week 6-8. Groups fed the APs enriched diets had significant ameliorated interleukin (IL)-1β and interferon (IFN)-γ mRNA expression after 6 and 8 weeks of feeding. However, IL-10 and major histocompatibility complex (MHC)-1 mRNA expressions were significant enhanced in catla fed all APs diets on week 8. APs enriched diets revealed significant improved tumor necrosis factor (TNF)-α and TNF receptor-associated factor-6 (TRAF6) mRNA expression on week 4, but toll-like receptor-2 (TLR2) and TLR4 mRNA expression were significant enhanced by diet EB and EC after weeks 6 and 8. Similarly, the lysozyme (Lyz)-C and Lyz-G mRNA levels in the head kidney (HK) increased by APs feeding on weeks 6 and 8, whereas the EB diet, the expression of nucleotide binding oligomerization domain-1 (NOD1) was significantly improved on weeks 6 and 8, but NOD2 mRNA expression was only significant enhanced after 8 weeks of diet EB. By feeding healthy catla and E. tarda challenged fish fed diet EB, resulted in significantly increased growth, haemato-biochemical indices, metabolic-digestive enzymes, antioxidant activities, innate-adaptive immune responses, and cytokine gene expression mainly between 6 to 8 weeks.
Keywords: Astragalus polysaccharides (APs); Catla catla; Chemokine genes; Edwardsiella tarda; Innate-adaptive immune response.
Publication
Journal: Journal of Physical Chemistry B
January/24/2022
Abstract
The interaction between graphene oxide (GO) and lysozyme (LYZ) in aqueous solution was investigated for GO specific surface area determination and for the thermodynamic description of the process. It was experimentally proved that LYZ is a much better adsorbate than the most common methylene blue, allowing the determination of genuine GO surface area. Our fluorescence spectroscopy results indicate that LYZ molecules interact with GO at high- and low-affinity sites depending on the surface coverage, reflecting the protein mono- and multilayer formation, respectively. The lack of the secondary structure changes confirms LYZ usability as a model adsorbate. The calculated values of thermodynamic parameters (Δ(ΔH0) = -195.0 kJ/mol and Δ(ΔS0) = -621.3 J/molK) indicate that the interactions are exothermic, enthalpy-driven. All the reported results reveal the physical nature of the LYZ-GO interaction at the studied concentration ratios.
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Publication
Journal: ACS Applied Bio Materials
January/11/2022
Abstract
The fabrication of tailor-made structural materials for the selective extraction of low-abundance biomacromolecules from biosamples is highly desirable. In this work, a novel type of hierarchically bulky imprinted polydopamine/CaCO3 microparticles using polymers with different charges was applied to selectively enrich the target protein lysozyme (Lyz). By different polymers mediating, three-dimensional controllable macro- and mesoporous microparticles were prepared after removing the supporting material CaCO3 and the template protein Lyz. In particular, poly(styrenesulfonate sodium) (PSS)-assisted hierarchical bulky imprinted microparticles (denoted as PSS-PDA-MIP) had the best adsorption capacity for Lyz. The maximum binding capacity of PSS-PDA-MIP particles for Lyz was 1203.4 mg g-1, five times higher than its corresponding nonimprinted polymer (NIP) particles. The results also demonstrated that the selectivity of PSS-PDA-MIP microparticles for Lyz was effective with multiple protein mixtures, diluted egg whites, and spiked human blood serum, which can be attributed to the macroporous channels, the specific stereo cavities, and the assisted-polymer functional groups.
Keywords: hierarchically porous structure; molecularly imprinting technology; polymer-assisted; sacrificing template; target protein enrichment.
Publication
Journal: Particle and Fibre Toxicology
January/20/2022
Abstract
Background: Coal dust particles (CDP), an inevitable by-product of coal mining for the environment, mainly causes coal workers' pneumoconiosis (CWP). Long-term exposure to coal dust leads to a complex alternation of biological processes during regeneration and repair in the healing lung. However, the cellular and complete molecular changes associated with pulmonary homeostasis caused by respiratory coal dust particles remain unclear.
Methods: This study mainly investigated the pulmonary toxicity of respirable-sized CDP in mice using unbiased single-cell RNA sequencing. CDP (< 5 μm) collected from the coal mine was analyzed by Scanning Electron Microscope (SEM) and Mass Spectrometer. In addition, western blotting, Elisa, QPCR was used to detect gene expression at mRNA or protein levels. Pathological analysis including HE staining, Masson staining, immunohistochemistry, and immunofluorescence staining were performed to characterize the structure and functional alternation in the pneumoconiosis mouse and verify the reliability of single-cell sequencing results.
Results: SEM image and Mass Spectrometer analysis showed that coal dust particles generated during coal mine production have been crushed and screened with a diameter of less than 5 µm and contained less than 10% silica. Alveolar structure and pulmonary microenvironment were destroyed, inflammatory and death (apoptosis, autophagy, and necrosis) pathways were activated, leading to pneumoconiosis in post 9 months coal dust stimulation. A distinct abnormally increased alveolar type 2 epithelial cell (AT2) were classified with a highly active state but reduced the antimicrobial-related protein expression of LYZ and Chia1 after CDP exposure. Beclin1, LC3B, LAMP2, TGF-ß, and MLPH were up-regulated induced by CDP, promoting autophagy and pulmonary fibrosis. A new subset of macrophages with M2-type polarization double expressed MLPH + /CD206 + was found in mice having pneumoconiosis but markedly decreased after the Vitamin D treatment. Activated MLPH + /CD206 + M2 macrophages secreted TGF-β1 and are sensitive to Vitamin D treatment.
Conclusions: This is the first study to reconstruct the pathologic progression and transcriptome pattern of coal pneumoconiosis in mice. Coal dust had obvious toxic effects on lung epithelial cells and macrophages and eventually induced pulmonary fibrosis. CDP-induced M2-type macrophages could be inhibited by VD, which may be related to the alleviation of the pulmonary fibrosis process.
Keywords: Alveolar regeneration; Coal dust pulmonary disease; Epithelial cells; Macrophage subset phenotype activation; Pulmonary toxicity; Single-cell RNA sequencing.
Publication
Journal: Ecotoxicology and Environmental Safety
February/7/2022
Abstract
In this study, γ-aminobutyric acid (GABA) was examined as an additional supplement to improve the ammonia stress resistance of S. pharaonis. Specifically, we added different doses of GABA (0, 20, 40, 60, 80, and 100 mg/kg) to food, cultivated S. pharaonis in regular seawater for 8 weeks and then in 8.40 mg/L ammonia seawater for 48 h and then investigated the accumulation of ammonia (the hepatic ammonia content), ammonia detoxification process (the urea content), antioxidant enzymes (superoxide dismutase (SOD) and catalase (CAT) enzyme activities), immune response (the serum haemolytic complement (C3) and lysozyme (LYZ) contents), membrane lipid peroxidation (malondialdehyde (MDA)) and histopathology of the liver. The results showed that ammonia poisoning could induce ammonia and MDA accumulation and subsequently lead to oxidative stress (decreases in SOD and CAT activities), immunosuppression (reductions in the haemolytic C3 and LYZ content), and histopathological injury in the liver. The application of GABA had a significant effect on alleviating the adverse effect of ammonia poisoning, and 80-100 mg/kg treatment exerted the best effect. This treatment significantly reduced the ammonia and MDA contents, significantly increased the urea content, increased the SOD, CAT, C3 and LYZ activities, reduced the MDA content, suppressed membrane lipid peroxidation, and significantly improved the histopathological injury to the liver. In summary, the results could provide a new method for mitigating liver damage, alleviating the physiological and metabolic disorders caused by ammonia stress in cuttlefish, and provide a theoretical basis for the application of GABA in alleviating ammonia poisoning.
Keywords: Ammonia toxicity; Sepia pharaonis; γ-Aminobutyric acid.
Publication
Journal: Acta Biomaterialia
February/11/2022
Abstract
Bacteria in the external environment inevitably invade the wound and subsequently colonize the wound surface during surgery and biomedical operations, which slows down the process of wound healing and tissue repair; this poses a significant threat to human health. Therefore, the development of an intelligent antibacterial surface has become the focus of research in the field of antimicrobial strategies, which has important social and economic significance. Here, we present a simple approach of producing an ionic interaction-driven anionic activation substratum which is then functionalized with cationic molecules through coulombic interactional immobilization. The switchable multifunctional antibacterial surface can decrease bacterial attachment and inactivate the attached microorganisms, thus overcoming the conventional challenge for antibacterial surfaces. Briefly, poly (3-sulfopropyl methacrylate potassium salt) (PSPMA) brushes were constructed by surface-initiated atom transfer radical polymerization on silicon or cotton fabric substrates, and a positive-charged component, namely lysozyme (LYZ), hexadecyl trimethyl ammonium bromide (CTAB) or chitosan (CS), was loaded on negative-charged sulfonate groups through electrostatic interactions. The resultant brush-grafted surfaces exhibited more than ∼95.5% bactericidal efficacy and ∼92.8% release rate after the introduction of an adequate amount of contra-ions (1.0 M; Na+ & Cl-) against both Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus, thus achieving a regenerated surface through the cyclic process of "assembly-dissociation"." Smart cotton fabric (Fabric-PSPMA/LYZ and Fabric-PSPMA/CS) surfaces were constructed, which were found to promote wound epidermal tissue regeneration with a higher efficiency after 7-day in vivo studies. This ionic interaction-driven method used in the present work is simple and can reversibly renew antibacterial surfaces, which will help in the wider utilization of switchable antibacterial materials with a more ecologic and economic significance. STATEMENT OF SIGNIFICANCE: Smart antibacterial surfaces with renewable characteristics have attracted considerable interests over the past few years. Here, we used ionic interaction-driven force to manipulate dynamic conformational changes in PSPMA surface brushes, accompanied by highly switchable bacteria killing and bacteria releasing behaviors. Different cationic molecules were also designed for assembly/dissociation on the PSPMA-modified surfaces, and the essential parameters, including chemical structures, molecular weight, and cationic charge density, were investigated. With the refined structural combinations and the balance of bacteria killing/bacteria releasing behaviors, smart cotton fabrics (e.g., Fabric-PSPMA/lysozyme and Fabric-PSPMA/chitosan) were designed that could promote wound healing and tissue repair. These results contribute to the fundamental understanding of a switchable cationic-anionic pair design and the corresponding practical, renewable, highly antibacterial fabric.
Keywords: Antibacterial surface; Polymer brushes; Surface antifouling; Wound healing.
Results with error correction
Publication
Journal: Nature Genetics
July/1/2012
Abstract
Trans-acting genetic variants have a substantial, albeit poorly characterized, role in the heritable determination of gene expression. Using paired purified primary monocytes and B cells, we identify new predominantly cell type-specific cis and trans expression quantitative trait loci (eQTLs), including multi-locus trans associations to LYZ and KLF4 in monocytes and B cells, respectively. Additionally, we observe a B cell-specific trans association of rs11171739 at 12q13.2, a known autoimmune disease locus, with IP6K2 (P = 5.8 × 10(-15)), PRIC285 (P = 3.0 × 10(-10)) and an upstream region of CDKN1A (P = 2 × 10(-52)), suggesting roles for cell cycle regulation and peroxisome proliferator-activated receptor γ (PPARγ) signaling in autoimmune pathogenesis. We also find that specific human leukocyte antigen (HLA) alleles form trans associations with the expression of AOAH and ARHGAP24 in monocytes but not in B cells. In summary, we show that mapping gene expression in defined primary cell populations identifies new cell type-specific trans-regulated networks and provides insights into the genetic basis of disease susceptibility.
Publication
Journal: Gut
July/20/2008
Abstract
OBJECTIVE
Reduced ileal Paneth cell alpha-defensin expression has been reported to be associated with Crohn's disease, especially in patients carrying NOD2 mutations. The aim of this study was to independently assess whether NOD2, alpha-defensins and Crohn's disease are linked.
METHODS
Using quantitative real-time polymerase chain reaction (RT-PCR), we measured the mRNA expression levels of key Paneth cell antimicrobial peptides (DEFA5, DEFA6, LYZ, PLA2G2A), inflammatory cytokines [interkelukin 6 (IL6) and IL8], and a marker of epithelial cell content, villin (VIL1) in 106 samples from both affected ileum (inflamed Crohn's disease cases, n = 44) and unaffected ileum (non-inflamed; Crohn's disease cases, n = 51 and controls, n = 11). Anti-human defensin 5 (HD-5) and haematoxylin/eosin immunohistochemical staining was performed on parallel sections from NOD2 wild-type and NOD2 mutant ileal Crohn's disease tissue.
RESULTS
In Crohn's disease patients, DEFA5 and DEFA6 mRNA expression levels were 1.9- and 2.2-fold lower, respectively, in histologically confirmed inflamed ileal mucosa after adjustment for confounders (DEFA5, p<0.001; DEFA6, p = 0.001). In contrast to previous studies, we found no significant association between alpha-defensin expression and NOD2 genotype. HD-5 protein data supports these RNA findings. The reduction in HD-5 protein expression appears due to surface epithelial cell loss and reduced Paneth cell numbers as a consequence of tissue damage.
CONCLUSIONS
Reduction in alpha-defensin expression is independent of NOD2 status and is due to loss of surface epithelium as a consequence of inflammatory changes rather than being the inciting event prior to inflammation in ileal Crohn's disease.
Publication
Journal: Clinical Cancer Research
June/6/2016
Abstract
OBJECTIVE
Blocking the immunosuppressive PD-1/PD-L1 pathway has antitumor activity in multiple cancer types, and PD-L1 expression on tumor cells and infiltrating myeloid cells correlates with the likelihood of response. We previously found that IFNG (interferon-gamma) was overexpressed by tumor-infiltrating lymphocytes in PD-L1(+) versus PD-L1(-) melanomas, creating adaptive immune resistance by promoting PD-L1 display. This study was undertaken to identify additional factors in the PD-L1(+) melanoma microenvironment coordinately contributing to immunosuppression.
METHODS
Archived, formalin-fixed paraffin-embedded melanoma specimens were assessed for PD-L1 protein expression at the tumor cell surface with IHC. Whole-genome expression analysis, quantitative (q)RT-PCR, IHC, and functional in vitro validation studies were used to assess factors differentially expressed in PD-L1(+) versus PD-L1(-) melanomas.
RESULTS
Functional annotation clustering based on whole-genome expression profiling revealed pathways upregulated in PD-L1(+) melanomas, involving immune cell activation, inflammation, and antigen processing and presentation. Analysis by qRT-PCR demonstrated overexpression of functionally related genes in PD-L1(+) melanomas, involved in CD8(+) T-cell activation (CD8A, IFNG, PRF1, and CCL5), antigen presentation (CD163, TLR3, CXCL1, and LYZ), and immunosuppression [PDCD1 (PD-1), CD274 (PD-L1), and LAG3, IL10]. Functional studies demonstrated that some factors, including IL10 and IL32-gamma, induced PD-L1 expression on monocytes but not tumor cells.
CONCLUSIONS
These studies elucidate the complexity of immune checkpoint regulation in the tumor microenvironment, identifying multiple factors likely contributing to coordinated immunosuppression. These factors may provide tumor escape mechanisms from anti-PD-1/PD-L1 therapy, and should be considered for cotargeting in combinatorial immunomodulation treatment strategies.
Publication
Journal: Developmental and Comparative Immunology
April/10/2008
Abstract
By enhancer trap screening we identified a transgenic zebrafish line showing leukocyte-specific YFP expression during late embryo and early larval development. Its enhancer detection insertion was mapped near a novel member of the myc proto-oncogene family, encoding transcription factors known to be important for regulating human myelopoiesis. Characterization of the zebrafish myc family showed that only this particular myc gene is strongly expressed in leukocytes. To identify the myc/YFP-expressing cell type, we re-examined specificity of described myeloid markers by multiplex fluorescent in situ hybridization, showing that lcp1 can be considered as a general leukocyte marker, csf1r as a macrophage-specific marker, and mpx and lyz as neutrophil-specific markers. Subsequent colocalization analysis defined the YFP-positive cells as a subset of the neutrophil population. Using real-time confocal imaging we demonstrate that these cells migrate to sites of inflammation and are involved in innate immune responses towards infections, including Mycobacterium marinum-induced granuloma formation.
Publication
Journal: PLoS Genetics
February/29/2012
Abstract
One major expectation from the transcriptome in humans is to characterize the biological basis of associations identified by genome-wide association studies. So far, few cis expression quantitative trait loci (eQTLs) have been reliably related to disease susceptibility. Trans-regulating mechanisms may play a more prominent role in disease susceptibility. We analyzed 12,808 genes detected in at least 5% of circulating monocyte samples from a population-based sample of 1,490 European unrelated subjects. We applied a method of extraction of expression patterns-independent component analysis-to identify sets of co-regulated genes. These patterns were then related to 675,350 SNPs to identify major trans-acting regulators. We detected three genomic regions significantly associated with co-regulated gene modules. Association of these loci with multiple expression traits was replicated in Cardiogenics, an independent study in which expression profiles of monocytes were available in 758 subjects. The locus 12q13 (lead SNP rs11171739), previously identified as a type 1 diabetes locus, was associated with a pattern including two cis eQTLs, RPS26 and SUOX, and 5 trans eQTLs, one of which (MADCAM1) is a potential candidate for mediating T1D susceptibility. The locus 12q24 (lead SNP rs653178), which has demonstrated extensive disease pleiotropy, including type 1 diabetes, hypertension, and celiac disease, was associated to a pattern strongly correlating to blood pressure level. The strongest trans eQTL in this pattern was CRIP1, a known marker of cellular proliferation in cancer. The locus 12q15 (lead SNP rs11177644) was associated with a pattern driven by two cis eQTLs, LYZ and YEATS4, and including 34 trans eQTLs, several of them tumor-related genes. This study shows that a method exploiting the structure of co-expressions among genes can help identify genomic regions involved in trans regulation of sets of genes and can provide clues for understanding the mechanisms linking genome-wide association loci to disease.
Publication
Journal: Proceedings of the National Academy of Sciences of the United States of America
July/15/2004
Abstract
The Lyz endolysin of bacteriophage P1 was found to cause lysis of the host without a holin. Induction of a plasmid-cloned lyz resulted in lysis, and the lytic event could be triggered prematurely by treatments that dissipate the proton-motive force. Instead of requiring a holin, export was mediated by an N-terminal transmembrane domain (TMD) and required host sec function. Exported Lyz of identical SDS/PAGE mobility was found in both the membrane and periplasmic compartments, indicating that periplasmic Lyz was not generated by the proteolytic cleavage of the membrane-associated form. In gene fusion experiments, the Lyz TMD directed PhoA to both the membrane and periplasmic compartments, whereas the TMD of the integral membrane protein FtsI restricts Lyz to the membrane. Thus, the N-terminal domain of Lyz is both necessary and sufficient not only for export of this endolysin to the membrane but also for its release into the periplasm. The unusual N-terminal domain, rich in residues that are weakly hydrophobic, thus functions as a signal-arrest-release sequence, which first acts as a normal signal-arrest domain to direct the endolysin to the periplasm in membrane-tethered form and then allows it to be released as a soluble active enzyme in the periplasm. Examination of the protein sequences of related bacteriophage endolysins suggests that the presence of an N-terminal signal-arrest-release sequence is not unique to Lyz. These observations are discussed in relation to the role of holins in the control of host lysis by bacteriophage encoding a secretory endolysin.
Publication
Journal: Gastroenterology
August/3/2010
Abstract
OBJECTIVE
Intestinal metaplasia (IM) and spasmolytic polypeptide-expressing metaplasia (SPEM) are precursors to gastric carcinogenesis. We sought to identify molecular biomarkers of gastric metaplasias and gastric cancer by gene expression profiling of metaplastic lesions from patients.
METHODS
Complementary DNA microarray analysis was performed on IM and SPEM cells isolated from patient samples using laser capture microdissection. Up-regulated transcripts in metaplastic lesions were confirmed by immunostaining analysis in IM, SPEM, and gastric cancer tissues. Proteins that were highly expressed specifically in gastric cancer tissues were analyzed for their association with survival in a test set (n = 450) and a validation set (n = 502) of samples from gastric cancer patients.
RESULTS
Compared with normal chief cells, 858 genes were differentially expressed in IM or SPEM samples. Immunostaining was detected for 12 proteins, including 3 new markers of IM (ACE2, LGALS4, AKR1B10) and 3 of SPEM (OLFM4, LYZ, DPCR1). Of 13 proteins expressed in IM or SPEM, 8 were expressed by 17%-50% of human gastric cancer tissues (MUC13, OLFM4, CDH17, KRT20, MUC5AC, LGALS4, AKR1B10, REG4). Expression of CDH17 or MUC13 correlated with patient survival in the test and validation sets. Multivariate analysis showed that CDH17 was an independent prognostic factor in patients with stage I or node-negative disease.
CONCLUSIONS
We identified several novel biomarkers for IM, SPEM, and gastric cancer using gene expression profiling of human metaplastic lesions. Expression of CDH17 and MUC13 was up-regulated in gastric cancer tissues. CDH17 is a promising prognostic marker for early stage gastric cancer.
Publication
Journal: Science
January/18/2005
Abstract
The P1 lysozyme Lyz is secreted to the periplasm of Escherichia coli and accumulates in an inactive membrane-tethered form. Genetic and biochemical experiments show that, when released from the bilayer, Lyz is activated by an intramolecular thiol-disulfide isomerization, which requires a cysteine in its N-terminal SAR (signal-arrest-release) domain. Crystal structures confirm the alternative disulfide linkages in the two forms of Lyz and reveal dramatic conformational differences in the catalytic domain. Thus, the exported P1 endolysin is kept inactive by three levels of control-topological, conformational, and covalent-until its release from the membrane is triggered by the P1 holin.
Publication
Journal: Hypertension
August/21/2008
Abstract
We conducted a genome-wide association study to identify novel genes influencing diastolic blood pressure (BP) response to hydrochlorothiazide, a commonly prescribed thiazide diuretic preferred for the treatment of high BP. Affymetrix GeneChip Human Mapping 100K Arrays were used to measure single nucleotide polymorphisms across the 22 autosomes in 194 non-Hispanic black subjects and 195 non-Hispanic white subjects with essential hypertension selected from opposite tertiles of the race- and sex-specific distributions of age-adjusted diastolic BP response to hydrochlorothiazide (25 mg daily, PO, for 4 weeks). The black sample consisted of 97 "good" responders (diastolic BP response [mean+/-SD]=-18.3+/-4.2 mm Hg; age=47.1+/-6.1 years; 51.5% women) and 97 "poor" responders (diastolic BP response=-0.18+/-4.3; age=47.4+/-6.5 years; 51.5% women). Haplotype trend regression identified a region of chromosome 12q15 in which haplotypes constructed from 3 successive single nucleotide polymorphisms (rs317689, rs315135, and rs7297610) in proximity to lysozyme (LYZ), YEATS domain containing 4 (YEATS4), and fibroblast growth receptor substrate 2 (FRS2) were significantly associated with diastolic BP response (nominal P=2.39 x 10(-7); Bonferroni corrected P=0.024; simulated experiment-wise P=0.040). Genotyping of 35 additional single nucleotide polymorphisms selected to "tag" linkage disequilibrium blocks in these genes provided corroboration that variation in LYZ and YEATS4 was associated with diastolic BP response in a statistically independent data set of 291 black subjects and in the sample of 294 white subjects. These results support the use of genome-wide association analyses to identify novel genes influencing antihypertensive drug responses.
Publication
Journal: Proceedings of the National Academy of Sciences of the United States of America
June/22/2009
Abstract
Sanfilippo syndrome type B (mucopolysaccharidosis III B, MPS III B) is an autosomal recessive, neurodegenerative disease of children, characterized by profound mental retardation and dementia. The primary cause is mutation in the NAGLU gene, resulting in deficiency of alpha-N-acetylglucosaminidase and lysosomal accumulation of heparan sulfate. In the mouse model of MPS III B, neurons and microglia display the characteristic vacuolation of lysosomal storage of undegraded substrate, but neurons in the medial entorhinal cortex (MEC) display accumulation of several additional substances. We used whole genome microarray analysis to examine differential gene expression in MEC neurons isolated by laser capture microdissection from Naglu(-/-) and Naglu(+/-) mice. Neurons from the lateral entorhinal cortex (LEC) were used as tissue controls. The highest increase in gene expression (6- to 7-fold between mutant and control) in MEC and LEC neurons was that of Lyzs, which encodes lysozyme, but accumulation of lysozyme protein was seen in MEC neurons only. Because of a report that lysozyme induced the formation of hyperphosphorylated tau (P-tau) in cultured neurons, we searched for P-tau by immunohistochemistry. P-tau was found in MEC of Naglu(-/-) mice, in the same neurons as lysozyme. In older mutant mice, it was also seen in the dentate gyrus, an area important for memory. Electron microscopy of dentate gyrus neurons showed cytoplasmic inclusions of paired helical filaments, P-tau aggregates characteristic of tauopathies-a group of age-related dementias that include Alzheimer disease. Our findings indicate that the Sanfilippo syndrome type B should also be considered a tauopathy.
Publication
Journal: Hepatology
August/29/2013
Abstract
Ischemia-reperfusion (I/R) injury is a process whereby an initial hypoxic insult and subsequent return of blood flow leads to the propagation of innate immune responses and organ injury. The necessity of the pattern recognition receptor, Toll-like receptor (TLR)4, for this innate immune response has been previously shown. However, TLR4 is present on various cell types of the liver, both immune and nonimmune cells. Therefore, we sought to determine the role of TLR4 in individual cell populations, specifically, parenchymal hepatocytes (HCs), myeloid cells, including Kupffer cells, and dendritic cells (DCs) subsequent to hepatic I/R. When HC-specific (Alb-TLR4(-/-) ) and myeloid-cell-specific (Lyz-TLR4(-/-) ) TLR4 knockout (KO) mice were subjected to warm hepatic ischemia, there was significant protection in these mice, compared to wild type (WT). However, the protection afforded in these two strains was significantly less than global TLR4 KO (TLR4(-/-) ) mice. DC-specific TLR4(-/-) (CD11c-TLR4(-/-) ) mice had significantly increased hepatocellular damage, compared to WT mice. Circulating levels of high-mobility group box 1 (HMGB1) were significantly reduced in Alb-TLR4(-/-) mice, compared to WT, Lyz-TLR4(-/-) , CD11c-TLR4(-/-) mice and equivalent to global TLR4(-/-) mice, suggesting that TLR4-mediated HMGB1 release from HCs may be a source of HMGB1 after I/R. HCs exposed to hypoxia responded by rapidly phosphorylating the mitogen-activated protein kinases, c-Jun-N-terminal kinase (JNK) and p38, in a TLR4-dependent manner; inhibition of JNK decreased release of HMGB1 after both hypoxia in vitro and I/R in vivo.
CONCLUSIONS
These results provide insight into the individual cellular response of TLR4. The parenchymal HC is an active participant in sterile inflammatory response after I/R through TLR4-mediated activation of proinflammatory signaling and release of danger signals, such as HMGB1.
Publication
Journal: BMC Genomics
January/17/2010
Abstract
BACKGROUND
Information generated via microarrays might uncover interactions between the mammary gland and Streptococcus uberis (S. uberis) that could help identify control measures for the prevention and spread of S. uberis mastitis, as well as improve overall animal health and welfare, and decrease economic losses to dairy farmers. The main objective of this study was to determine the most affected gene networks and pathways in mammary tissue in response to an intramammary infection (IMI) with S. uberis and relate these with other physiological measurements associated with immune and/or metabolic responses to mastitis challenge with S. uberis O140J.
RESULTS
Streptococcus uberis IMI resulted in 2,102 (1,939 annotated) differentially expressed genes (DEG). Within this set of DEG, we uncovered 20 significantly enriched canonical pathways (with 20 to 61 genes each), the majority of which were signaling pathways. Among the most inhibited were LXR/RXR Signaling and PPARalpha/RXRalpha Signaling. Pathways activated by IMI were IL-10 Signaling and IL-6 Signaling which likely reflected counter mechanisms of mammary tissue to respond to infection. Of the 2,102 DEG, 1,082 were up-regulated during IMI and were primarily involved with the immune response, e.g., IL6, TNF, IL8, IL10, SELL, LYZ, and SAA3. Genes down-regulated (1,020) included those associated with milk fat synthesis, e.g., LPIN1, LPL, CD36, and BTN1A1. Network analysis of DEG indicated that TNF had positive relationships with genes involved with immune system function (e.g., CD14, IL8, IL1B, and TLR2) and negative relationships with genes involved with lipid metabolism (e.g., GPAM, SCD, FABP4, CD36, and LPL) and antioxidant activity (SOD1).
CONCLUSIONS
Results provided novel information into the early signaling and metabolic pathways in mammary tissue that are associated with the innate immune response to S. uberis infection. Our study indicated that IMI challenge with S. uberis (strain O140J) elicited a strong transcriptomic response, leading to potent activation of pro-inflammatory pathways that were associated with a marked inhibition of lipid synthesis, stress-activated kinase signaling cascades, and PPAR signaling (most likely PPARgamma). This latter effect may provide a mechanistic explanation for the inverse relationship between immune response and milk fat synthesis.
Publication
Journal: BMC Medicine
March/4/2007
Abstract
BACKGROUND
Pendred syndrome, an autosomal-recessive disorder characterized by deafness and goiter, is caused by a mutation of SLC26A4, which codes for the anion exchanger pendrin. We investigated the relationship between pendrin expression and deafness using mice that have (Slc26a4+/+ or Slc26a4+/-) or lack (Slc26a4-/-) a complete Slc26a4 gene. Previously, we reported that stria vascularis of adult Slc26a4-/- mice is hyperpigmented and that marginal cells appear disorganized. Here we determine the time course of hyperpigmentation and marginal cell disorganization, and test the hypothesis that inflammation contributes to this tissue degeneration.
METHODS
Slc26a4-/- and age-matched control (Slc26a4+/+ or Slc26a4+/-) mice were studied at four postnatal (P) developmental stages: before and after the age that marks the onset of hearing (P10 and P15, respectively), after weaning (P28-41) and adult (P74-170). Degeneration and hyperpigmentation stria vascularis was evaluated by confocal microscopy. Gene expression in stria vascularis was analyzed by microarray and quantitative RT-PCR. In addition, the expression of a select group of genes was quantified in spiral ligament, spleen and liver to evaluate whether expression changes seen in stria vascularis are specific for stria vascularis or systemic in nature.
RESULTS
Degeneration of stria vascularis defined as hyperpigmentation and marginal cells disorganization was not seen at P10 or P15, but occurred after weaning and was associated with staining for CD68, a marker for macrophages. Marginal cells in Slc26a4-/-, however, had a larger apical surface area at P10 and P15. No difference in the expression of Lyzs, C3 and Cd45 was found in stria vascularis of P15 Slc26a4+/- and Slc26a4-/- mice. However, differences in expression were found after weaning and in adult mice. No difference in the expression of markers for acute inflammation, including Il1a, Il6, Il12a, Nos2 and Nos3 were found at P15, after weaning or in adults. The expression of macrophage markers including Ptprc (= Cd45), Cd68, Cd83, Lyzs, Lgals3 (= Mac2 antigen), Msr2, Cathepsins B, S, and K (Ctsb, Ctss, Ctsk) and complement components C1r, C3 and C4 was significantly increased in stria vascularis of adult Slc26a4-/- mice compared to Slc26a4+/+ mice. Expression of macrophage markers Cd45 and Cd84 and complement components C1r and C3 was increased in stria vascularis but not in spiral ligament, liver or spleen of Slc26a4-/- compared to Slc26a4+/- mice. The expression of Lyzs was increased in stria vascularis and spiral ligament but not in liver or spleen.
CONCLUSIONS
The data demonstrate that hyperpigmentation of stria vascularis and marginal cell reorganization in Slc26a4-/- mice occur after weaning, coinciding with an invasion of macrophages. The data suggest that macrophage invasion contributes to tissue degeneration in stria vascularis, and that macrophage invasion is restricted to stria vascularis and is not systemic in nature. The delayed onset of degeneration of stria vascularis suggests that a window of opportunity exists to restore/preserve hearing in mice and therefore possibly in humans suffering from Pendred syndrome.
Publication
Journal: Journal of Biological Chemistry
October/18/2004
Abstract
Airway submucosal gland serous cells express the cystic fibrosis transmembrane conductance regulator (CFTR) and secrete antimicrobial, anti-inflammatory, and antioxidant molecules. In cystic fibrosis, diminished gland secretion may impair innate airway host defenses. We used Calu-3 cells as a serous cell model to study the types of proteins released, the pathways that release them, and the possible involvement of CFTR activity in protein release. Many proteins were secreted constitutively into the apical fluid and showed increased release to agonists. We identified some of them by high pressure liquid chromatography-mass spectrometry and reverse transcriptase PCR, including lysozyme, siderocalin (the protein NGAL), which inhibits bacterial growth by binding iron-containing siderophores, HSC-71, which is thought to have anti-inflammatory properties, and the serine protease inhibitors alpha-1-antitrypsin and alpha-1-antichymotrypsin, which may function as antimicrobials as well as play a potential role in diminishing the activation of epithelial Na(+) channels by serine proteases. We used an enzyme-linked immunosorbent assay to quantify lysozyme secretion by Calu-3 cells in response to various agonists and inhibitors. Forskolin increased the lysozyme secretion rate (J(lyz)) from 32 to 77 ng/hr/cm(2) (n = 36, p < 0.005). Thapsigargin increased J(lyz) from 40 to 63 ng/h/cm(2) (n = 16, p < 0.005), and forskolin plus thapsigargin further increased the forskolin-stimulated J(lyz) by 48% (n = 9, p < 0.05). 1-Ethyl-benzimidazolinone and carbachol were less effective. Glibenclamide inhibited basal and stimulated J(lyz), but clotrimazole was without effect. CFTR(inh)172 caused a small (15%) but significant inhibition of forskolin-stimulated J(lyz) without affecting basal J(lyz). Thus, Calu-3 cells secrete diverse proteins that in aggregate would be expected to suppress microbial growth, protect the airways from damage, and limit the activation of epithelial Na(+) channels via serine proteases.
Publication
Journal: Journal of Pathology
November/1/2011
Abstract
The intestinal microbiota is increasingly acknowledged to play a crucial role in the development of obesity. A shift in intestinal microbiota composition favouring the presence of Firmicutes over Bacteroidetes has been observed in obese subjects. A similar shift has been reported in mice with deficiency of active Paneth cell α-defensins. We aimed at investigating changes in Paneth cell antimicrobial levels in the gut of obese subjects. Next, we studied activation of the unfolded protein response (UPR) as a possible mechanism involved in altered Paneth cell function. Paneth cell numbers were counted in jejunal sections of 15 severely obese (BMI>> 35) and 15 normal weight subjects. Expression of Paneth cell antimicrobials human α-defensin 5 (HD5) and lysozyme were investigated using immunohistochemistry, qPCR, and western blot. Activation of the UPR was assessed with western blot. Severely obese subjects showed decreased protein levels of both HD5 and lysozyme, while Paneth cell numbers were unchanged. Lysozyme protein levels correlated inversely with BMI. Increased expression of HD5 (DEFA5) and lysozyme (LYZ) transcripts in the intestine of obese subjects prompted us to investigate a possible translational block caused by UPR activation. Binding protein (BiP) and activating transcription factor 4 (ATF4) levels were increased, confirming activation of the UPR in the gut of obese subjects. Furthermore, levels of both proteins correlated with BMI. Involvement of the UPR in the lowered antimicrobial protein levels in obese subjects was strongly suggested by a negative correlation between BiP levels and lysozyme levels. Additionally, indications of ER stress were apparent in Paneth cells of obese subjects. Our findings provide the first evidence for altered Paneth cell function in obesity, which may have important implications for the obesity-associated shift in microbiota composition. In addition, we show activation of the UPR in the intestine of obese subjects, which may underlie the observed Paneth cell compromise.
Publication
Journal: Biomaterials
November/28/2011
Abstract
Many biomedical applications of gold nanoparticles (NPs) rely on proteins that are covalently attached or adsorbed on the NP surface. The biological functionality of the protein-NP conjugate depends on the protein's ability to interact with target molecules, which is affected by NP characteristics such as size, curvature, aspect ratio, morphology, crystal structure, and surface chemistry. In the present study, the effect of gold nanoparticle morphology on the structure and function of adsorbed enzymes, lysozyme (Lyz) and α-chymotrypsin (ChT), has been investigated. Gold nanospheres (AuNS) were synthesized with diameters 10.6 ± 1 nm, and gold nanorods (AuNR) were synthesized with dimensions of (10.3 ± 2) × (36.4 ± 9) nm. Under saturating conditions, proteins adsorb with a higher surface density on AuNR when compared to AuNS. In the case of Lyz, adsorption on AuNS and AuNR resulted in a 10% and 15% loss of secondary structure, respectively, leading to conjugate aggregation and greatly reduced enzymatic activity. ChT retained most of its secondary structure and activity on AuNS and AuNR at low surface coverages; however, as protein loading approached monolayer conditions on AuNR, a 40% loss in secondary structure and 86% loss of activity was observed. Subsequent adsorption of ChT in multilayers on the AuNR surface allowed the conjugates to recover activity and remain stable. It is clear that AuNP morphology does affect adsorbed protein structure; a better understanding of these differences will be essential to engineer fully functional nanobioconjugates.
Publication
Journal: Scientific Reports
August/17/2017
Abstract
The ability of bacteriophages to kill bacteria is well known, as is their potential use as alternatives to antibiotics. As such, bacteriophages reach high doses locally through infection of their bacterial host in the human body. In this study we assessed the gene expression profile of peripheral blood monocytes from six donors for twelve immunity-related genes (i.e. CD14, CXCL1, CXCL5, IL1A, IL1B, IL1RN, IL6, IL10, LYZ, SOCS3, TGFBI and TNFA) induced by Staphylococcus aureus phage ISP and four Pseudomonas aeruginosa phages (i.e. PNM, LUZ19, 14-1 and GE-vB_Pae-Kakheti25). The phages were able to induce clear and reproducible immune responses. Moreover, the overall immune response was very comparable for all five phages: down-regulation of LYZ and TGFBI, and up-regulation of CXCL1, CXCL5, IL1A, IL1B, IL1RN, IL6, SOCS3 and TNFA. The observed immune response was shown to be endotoxin-independent and predominantly anti-inflammatory. Addition of endotoxins to the highly purified phages did not cause an immune response comparable to the one induced by the (endotoxin containing) phage lysate. In addition, the use of an intermediate level of endotoxins tipped the immune response to a more anti-inflammatory response, i.e. up-regulation of IL1RN and a strongly reduced expression of CXCL1 and CXCL5.
Publication
Journal: Journal of Dairy Science
April/28/2013
Abstract
MicroRNA (miRNA) are small single-stranded noncoding RNA with important roles in regulating innate immunity in nonruminants via transcriptional and posttranscriptional mechanisms. Mastitis causes significant losses in the dairy industry and a wealth of large-scale mRNA expression data from mammary tissue have provided fundamental insights into the tissue adaptations to pathogens. We studied the expression of 14 miRNA (miR-10a, -15b, -16a, -17, -21, -31, -145, -146a, -146b, -155, -181a, -205, -221, and -223) associated with regulation of innate immunity and mammary epithelial cell function in tissue challenged with Streptococcus uberis. Those data, along with microarray expression of 2,102 differentially expressed genes, were used for bioinformatics analysis to uncover putative target genes and the most affected biological pathways and functions. Three miRNA (181a, 16, and 31) were downregulated approximately 3- to 5-fold and miR-223 was upregulated approximately 2.5-fold in infected versus healthy tissue. Among differentially expressed genes due to infection, bioinformatics analysis revealed that the studied miRNA share in the regulation of a large number of metabolic (SCD, CD36, GPAM, and FASN), immune/oxidative stress (TNF, IL6, IL10, SOD2, LYZ, and TLR4), and cellular proliferation/differentiation (FOS and CASP4) target genes. This level of complex regulation was underscored by the coordinate effect revealed by bioinformatics on various cellular pathways within the Kyoto Encyclopedia of Genes and Genomes database. Most pathways associated with "cellular processes," "organismal systems," and "diseases" were activated by putative target genes of miR-31 and miR-16a, with an overlapping activation of "immune system" and "signal transduction." A pronounced effect and activation of miR-31 target genes was observed within "folding, sorting, and degradation," "cell growth and death," and "cell communication" pathways, whereas a marked inhibition of "lipid metabolism" occurred. Putative targets of miR-181a had a strong effect on FcγR-mediated phagocytosis, toll-like receptor signaling, and antigen processing and presentation, which were activated during intramammary infections. The targets of both miR-31 and miR-223 had an inhibitory effect on "lipid metabolism." Overall, the combined analyses indicated that changes in mammary tissue immune, metabolic, and cell growth-related signaling pathways during infection might have been mediated in part through effects of miRNA on gene transcription. Differential expression of miRNA supports the view from nonruminant cells/tissues that certain miRNA might be essential for the tissue's adaptive response to infection.
Publication
Journal: Analytical and Bioanalytical Chemistry
December/1/2004
Abstract
Nano-electrospray-ionization mass spectrometry (nano-ESI-MS) is employed here to describe equilibrium protein conformational transitions and to analyze the influence of instrumental settings, pH, and solvent surface tension on the charge-state distributions (CSD). A first set of experiments shows that high flow rates of N(2) as curtain gas can induce unfolding of cytochrome c (cyt c) and myoglobin (Mb), under conditions in which the stability of the native protein structure has already been reduced by acidification. However, it is possible to identify conditions under which the instrumental settings are not limiting factors for the conformational stability of the protein inside ESI droplets. Under such conditions, equilibrium unfolding transitions described by ESI-MS are comparable with those obtained by other established biophysical methods. Experiments with the very stable proteins ubiquitin (Ubq) and lysozyme (Lyz) enable testing of the influence of extreme pH changes on the ESI process, uncoupled from acid-induced unfolding. When HCl is used for acidification, Ubq and Lyz mass spectra do not change between pH~7 and pH 2.2, indicating that the CSD is highly characteristic of a given protein conformation and not directly affected by even large pH changes. Use of formic or acetic acid for acidification of Ubq solutions results in major spectral changes that can be interpreted in terms of protein unfolding as a result of the increased hydrophobicity of the solvent. On the other hand, Lyz, cyt c, and Mb enable direct comparison of protein CSD (corresponding to either the folded or the unfolded protein) in HCl or acetic acid solutions at low pH. The values of surface tension for these solutions differ significantly. Confirming indications already present in the literature, we observe very similar CSD under these solvent conditions for several proteins in either compact or disordered conformations. The same is true for comparison between water and water-acetic acid for folded cyt c and Lyz. Thus, protein CSD from water-acetic solutions do not seem to be limited by the low surface tension of acetic acid as previously suggested. This result could reflect a general lack of dependence of protein CSD on the surface tension of the solvent. However, it is also possible that the effect of acetic acid on the precursor ESI droplets is smaller than generally assumed.
Publication
Journal: Experimental Eye Research
May/25/2009
Abstract
Recently, we reported development of the C57BL/6.NOD-Aec1Aec2 mouse carrying two genetic intervals derived from the NOD mouse. These two genetic regions confer Sjögren's syndrome (SjS)-like disease in SjS-non-susceptible C57BL/6 mice. In an attempt to define the molecular bases underlying onset of dacryoadenitis and subsequently keratoconjunctivitis sicca (or xerophthalmia) in the C57BL/6.NOD-Aec1Aec2 mouse model, we have carried out a study utilizing microarray technology. Using oligonucleotide microarrays, gene expression profiles of lacrimal glands at 4, 8, 12, 16 and 20weeks of age were generated for C57BL/6.NOD-Aec1Aec2 male mice. Analyses using Linear Models for Microarray Analysis package and B-statistics, 552 genes were identified as being differentially expressed (adjusted p-value <0.01 and B <1.5) during the development of SjS-like disease. These 552 genes could be arranged into four clusters, with each cluster defining a unique pattern of temporal expression, while the individual genes within each cluster could be grouped according to related function. Using a pair-wise analysis, temporal changes in gene expressions provided profiles indicating that individual genes were differentially expressed at specific time points during development of SjS. In addition, multiple genes that have been reported to show, either in humans or mouse models, an association with autoimmunity and/or SjS, e.g., ApoE, Baff, Clu, Ctla4, Fas/Fasl, Irf5, Lyzs, Nfkb, Socs3, Stat4, Tap2, Tgfbeta1, Tnfa, and Vcam1 were also found to exhibit differential expressions, both quantitatively and temporally. Selecting a few families of genes, e.g., cystatins, cathepsins, metalloproteinases, lipocalins, complement, kallikreins, carbonic anhydrases and tumor necrosis factors, it was noted that only a limited number of family members showed differential expressions, suggesting a restricted glandular expression. Utilizing these genes, pathways of inter-reactive genes have been constructed for apoptosis and fatty acid homeostasis, leading to modeling of possible underlying events inducing disease. Thus, these different approaches to analyze microarray data permit identification of multiple sets of genes of interest whose expressions and expression profiles may correlate with molecular mechanisms, signaling pathways and/or immunological processes involved in the development and onset of SjS in this mouse model, thereby providing new insight into the underlying cause or regulation of this disease.
Publication
Journal: Oncogene
November/5/2006
Abstract
The chromosomal translocation t(8;21) is associated with 10-15% of all cases of acute myeloid leukaemia (AML). The resultant fusion protein AML1/MTG8 interferes with haematopoietic gene expression and is an important regulator of leukaemogenesis. We studied the effects of small interfering RNA (siRNA)-mediated AML1/MTG8 depletion on global gene expression in t(8;21)-positive leukaemic cell lines and in primary AML blasts using cDNA arrays, oligonucleotide arrays and real-time reverse transcription-polymerase chain reaction (RT-PCR). Suppression of AML1/MTG8 results in the increased expression of genes associated with myeloid differentiation, such as AZU1, BPI, CTSG, LYZ and RNASE2 as well as of antiproliferative genes such as IGFBP7, MS4A3 and SLA both in blasts and in cell lines. Furthermore, expression levels of several genes affiliated with drug resistance or indicative of poor prognosis AML (BAALC, CD34, PRG2, TSPAN7) are affected by AML1/MTG8 depletion. In conclusion, siRNA-mediated suppression of AML1/MTG8 cause very similar changes in gene expression pattern in t(8;21)-positive cell lines and in primary AML blasts. Furthermore, the results suggest that the specific targeting of AML1/MTG8 function may be a promising approach for complementing existing treatment strategies.
Publication
Journal: GLIA
August/24/2005
Abstract
Olfactory ensheathing cells (OECs) accompany the axons of olfactory receptor neurons, which regenerate throughout life, from the olfactory mucosa into the olfactory bulb. OECs have shown widely varying efficacy in repairing the injured nervous system. Analysis of the transcriptome of OECs will help in understanding their biology and will provide tools for investigating the mechanisms of their efficacy and interactions with host tissues in lesion models. In this study, we compared the transcriptional profile of cultured OECs with that of Schwann cells (SCs) and astrocytes (ACs), two glial cell types to which OECs have similarities. Two biological replicates of RNA from cultured OECs, SCs, and ACs were hybridized to long oligo rat 5K arrays against a common reference pool of RNA (50% cultured fibroblast RNA and 50% neonatal rat brain RNA). Transcriptional profiles were analyzed by hierarchical clustering, Principal Components Analysis, and the Venn diagram. The three glial cell types had similarly increased or decreased expression of numerous transcripts compared with the reference. However, OECs were distinguishable from both SCs and ACs by a modest number of transcripts, which were significantly enriched or depleted. Furthermore, OECs and SCs were more closely related to each other than to ACs. Expression of selected transcripts not previously characterized in OECs, such as Lyz, Timp2, Gro1 (Cxcl1), Ccl2 (MCP1), Ctgf, and Cebpb, was validated by real-time reverse transcription-polymerase chain reaction (RT-PCR); immunohistochemistry in cultured OECs, SCs, and ACs, and adult tissues was performed to demonstrate their expression at the protein level.
Publication
Journal: American Journal of Physiology - Gastrointestinal and Liver Physiology
September/11/2007
Abstract
Small intestinal bacterial overgrowth (SIBO) may play an important role in the gastrointestinal complications of cystic fibrosis (CF). This work explored two potential factors in development of SIBO in the CF (cftr(tm1UNC)) mouse: impaired Paneth cell innate defenses and altered gastrointestinal motility. Postnatal differentiation of Paneth cells was followed by Defcr, Lyzs, and Ang4 gene expression, and SIBO was measured by quantitative PCR of the bacterial 16S rRNA gene. Paneth cell gene expression was low in 4-day-old CF and wild-type (WT) mice and increased similarly in both groups of mice between 12 and 16 days. Peak Paneth cell gene expression was reached by 40 days of age and was less for Defcr and Lyzs in CF mice compared with WT, whereas Ang4 levels were greater in CF mice. SIBO occurred by postnatal day 8 in CF mice, which is before Paneth cell development. With the use of gavaged rhodamine-dextran to follow motility, gastric emptying in CF mice was slightly decreased compared with WT, and small intestinal transit was dramatically less. Since antibiotics improve weight gain in CF mice, their effects on gastric emptying and small intestinal transit were determined. Antibiotics did not affect gastric emptying or transit in CF mice but did significantly slow intestinal transit in WT mice, suggesting a potential role of normal microflora in regulating transit. In conclusion, small intestinal transit was significantly slower in CF mice, and this is likely a major factor in SIBO in CF.
Publication
Journal: British Journal of Haematology
November/27/2011
Abstract
NUP98-HOXA9 [t(7;11) (p15;p15)] is associated with inferior prognosis in de novo and treatment-related acute myeloid leukaemia (AML) and contributes to blast crisis in chronic myeloid leukaemia (CML). We have engineered an inducible transgenic zebrafish harbouring human NUP98-HOXA9 under the zebrafish spi1(pu.1) promoter. NUP98-HOXA9 perturbed zebrafish embryonic haematopoiesis, with upregulated spi1 expression at the expense of gata1a. Markers associated with more differentiated myeloid cells, lcp1, lyz, and mpx were also elevated, but to a lesser extent than spi1, suggesting differentiation of early myeloid progenitors may be impaired by NUP98-HOXA9. Following irradiation, NUP98-HOXA9-expressing embryos showed increased numbers of cells in G2-M transition compared to controls and absence of a normal apoptotic response, which may result from an upregulation of bcl2. These data suggest NUP98-HOXA9-induced oncogenesis may result from a combination of defects in haematopoiesis and an aberrant response to DNA damage. Importantly, 23% of adult NUP98-HOXA9-transgenic fish developed a myeloproliferative neoplasm (MPN) at 19-23 months of age. In summary, we have identified an embryonic haematopoietic phenotype in a transgenic zebrafish line that subsequently develops MPN. This tool provides a unique opportunity for high-throughput in vivo chemical modifier screens to identify novel therapeutic agents in high risk AML.
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