The effects of Cadmium (Cd) exposure and the treatment with Zinc (Zn) on immune functions of splenocytes and cultured lymphocytes of rats were studied. The exposure of rats to Cd was at a dose of 2.2 mg/kg CdCl2, injected subcutaneously four times weekly for 2 months. Rats were supplemented with Zn (2.2 mg/kg ZnCl2, injected subcutaneously four times weekly for 2 months) one hour prior to Cd exposure. Spleens were removed and splenocytes were isolated and cultured. The proliferation capacity of lymphocytes and their homing to the spleen were studied. Ribonucleic acid (RNA) was extracted from stimulated lymphocytes in order to analyse gene expressions using RT-PCR. Accordingly, proliferation of lymphocytes was found to be suppressed in Cd-treated rats, both in vivo and in vitro. Zinc served to activate the proliferation of B and T lymphocytes in Cd-treated rats both in vivo and in vitro. Antigen-activated lymphocytes showed that Cd impaired the mRNA expression of CD68, Ccl22 and CXCL10. Zinc was not found to restore mRNA expression of these genes to the normal levels. Zinc was found to decrease the MDA level with replenishment of activity of key antioxidant enzymes and proteins in Cd-pre-treated animals significantly. Moreover, the histopathological examination of spleen samples also agreed with the molecular, immunological and redox findings. Hence, Zn is able to restore the normal structure, redox status and immunity in Cd-induced damage in the rat model system.

OBJECTIVE

Major chemokine receptors in the giant papillae of atopic keratoconjunctivitis (AKC) have yet to be determined. We evaluated chemokine receptor genes and their ligand expressions in upper tarsal conjunctival giant papillae of AKC with atopic dermatitis and/or asthma.

METHODS

CC, CXC, and CX3C chemokine receptor (R) gene expression levels in giant papillae of five clinically active AKC patients and in three age matched non-allergic control conjunctiva were measured with a multi-probe ribonuclease protection assay (RPA) system. The ligands of abundant chemokine receptors in the giant papillae were examined by immunohistochemistry or reverse transcription-polymerase chain reaction. Interleukin (IL)-4 and IL-13 gene expression levels were measured with RPA. Ligand expression in cultured human conjunctival fibroblasts was examined by reverse transcription-polymerase chain reaction.

RESULTS

High CXCR4 and CCR4 gene expression levels were detected in the giant papillae of all (CXCR4) and four out of five (CCR4) patients. As a CCR4-ligand, thymus and activation regulated cytokine (TARC/CCL17) rather than macrophage derived chemokine (MDC/CCL22), was predominant immunohistochemicaly in the giant papillae. Giant papillae with high CCR4 gene expression levels showed high IL-4 and IL-13 expression. Cultured human conjunctival fibroblasts express stromal cell derived factor-1 (SDF-1/CXCL12) in vitro.

CONCLUSIONS

CXCR4 and CCR4 are the major chemokine receptor genes expressed in the giant papillae of AKC with atopic dermatitis and/or asthma. Our findings suggest a role for CXCR4 and CCR4 in the formation of giant papillae.

The chemokines CCL17 (TARC) and CCL22 (MDC) function through the same receptor, CCR4, but have been proposed to differentially affect the immune response. To better understand the role of the individual ligands, a panel of rat anti-mouse CCL17 surrogate antibodies was generated that can be used to differentiate CCL17 and CCL22 function in vitro and in vivo. We have successfully identified a panel of neutralizing antibodies by screening hybridomas for the ability to inhibit CCL17-mediated calcium mobilization. Chemotaxis in response to CCL17 is also inhibited, providing further evidence that the antibodies in this panel are antagonistic. Using a recombinant cell line expressing human CCR4, we show that the antibodies block β-arrestin recruitment as evidence that the antibodies are specifically blocking CCL17 signaling through CCR4. The antibodies within this panel inhibit calcium mobilization with varying potency in the calcium flux assay, having apparent IC50 ranging from approximately 1 to >400 ng/mL. Although both CCL17 and CCL22 function through CCR4, only a single antibody was identified as having detectable binding to CCL22. This panel of CCL17-specific antibodies provides tools that can be used to differentiate CCL17 and CCL22 function through CCR4 interaction in vitro and in vivo.

Brucellosis is an endemic zoonotic infectious disease in the majority of developing countries, which causes huge economic losses. As immunogenic and protective antigens at the surface of Brucella spp., outer membrane proteins (Omps) are particularly attractive for developing vaccine and could have more relevant role in host-pathogen interactions. Omp16, a homolog to peptidoglycan-associated lipoproteins (Pals), is essential for Brucella survival in vitro. At present, the functions of Omp16 have been poorly studied. Here, the gene expression profile of RAW264.7 cells infected with Brucella suis vaccine strain 2 (B. suis S2) and ΔOmp16 was analyzed by RNA-seq to investigate the cellular response immediately after Brucella entry. The RNA-sequence analysis revealed that a total of 303 genes were significantly regulated by B. suis S2 24 h post-infection. Of these, 273 differentially expressed genes (DEGs) were upregulated, and 30 DEGs were downregulated. These DEGs were mainly involved in innate immune signaling pathways, including pattern recognition receptors (PRRs), proinflammatory cytokines, and chemokines by Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. In ΔOmp16-infected cells, the expression of 52 total cells genes was significantly upregulated and that of 9 total cells genes were downregulated compared to B. suis S2-infected RAW264.7 cells. The KEGG pathway analysis showed that several upregulated genes were proinflammatory cytokines and chemokines, such as interleukin (IL)-6, IL-11, IL-12β, C-C motif chemokine (CCL2), and CCL22. All together, we clearly demonstrate that ΔOmp16 can alter macrophage immune-related pathways to increase proinflammatory cytokines and chemokines, which provide insights into illuminating the Brucella pathogenic strategies.

Keywords: B. suis S2; Omp16; RAW264.7; RNA-seq; interactions.

Histopathological studies and animal models have suggested an inflammatory component in the pathomechanism of the CHMP2B associated frontotemporal dementia (FTD-3). In this cross-sectional study, serum and cerebrospinal fluid were analyzed for inflammatory markers in CHMP2B mutation carriers. Serum levels of CCL4 were increased throughout life. Serum levels of IL-15, CXCL10, CCL22 and TNF-α were significantly associated with cognitive decline, suggesting a peripheral inflammatory response to neurodegeneration. CSF levels of sTREM2 appeared to increase more rapidly with age in CHMP2B mutation carriers. The identification of a peripheral inflammatory response to disease progression supports the involvement of an inflammatory component in FTD-3.

Adult T-cell leukemia (ATL) is a malignancy of mature CD4+ T cells that is etiologically associated with the infection of human T-cell leukemia virus type 1 (HTLV-1), an exogenous human retrovirus. Previously, we have shown that leukemic cells of most ATL patients express CCR4, a chemokine receptor known to be selectively expressed by T cell subsets such as Th2 cells, skin-homing memory/effector T cells, and regulatory T cells. Therefore, the expression of CCR4 suggests that ATL cells are mostly derived from one of these T cell subsets. We have also shown that Tax, the HTLV-1-encoded potent transcriptional activator, strongly induces the expression of CCL22, a CCR4 ligand, which promotes the cell-dependent transmission of HTLV-1 from HTLV-1-infected T cells to CCR4+ target T cells by inducing close cell-to-cell interactions. We have also shown that ATL cells aberrantly express the AP-1 family member Fra-2 which, by forming the heterodimer with JunD, potently induces the expression of not only CCR4 but also the genes such as c-Myb, MDM2 and Bcl-6, the well-known proto-oncogenes. Thus, Fra-2 is a novel oncogene of ATL, and CCR4 may be regarded as a useful tumor marker of ATL.

OBJECTIVE

Macrophage-derived chemokine (CCL22) is a member of the CC-family of chemokines synthesized by monocyte-derived macrophages. Previous studies have reported a relationship between CCL22 and atherosclerosis and the role of histamine in this pathway. Histamine ncreases the CCL22 expression in human monocytes via the H2 receptor. In this study, we investigated the effects of CCL22 and the role of histamine in mouse monocytes with respect to atherosclerosis.

RESULTS

The expression of CCL22 was investigated in apolipoprotein E (apoE)-deficient mice. The mice had high serum concentrations of CCL22 and their atherosclerotic lesions contained abundant levels of CCL22. In addition, when the mouse monocyte cell line (J774A.1 cells) differentiated into macrophage-like cells, the cells showed a similar expression of CCL22 and reduced expression of H2 receptors. Histamine is synthesized from l-histidine by histidine decarboxylase (HDC) in a single enzymatic step. HDC knockout mice were compared with apoE/HDC double knockout mice. The findings indicated that the expression of CCL22 in atherosclerosis models is under the influence of histamine. In addition, in vitro studies using J774A.1 cells and an in vivo study using histamine receptor knockout mice showed that histamine stimulates the CCL22 expression via the histamine H2 receptor.

CONCLUSIONS

The current results support our previous CCL22 studies in the setting of human atherosclerosis and suggest that this molecule is involved in the atherogenic processes in a mouse model of atherosclerosis.

BACKGROUND

An intricate fetal-maternal immune crosstalk during pregnancy is essential for a healthy birth. Hence, the infection-induced alterations of maternal immunity often lead to adverse outcomes for mother and/or child. The emergence of Zika virus (ZIKV) infection in pregnant women has been associated with more than 3,000 cases of microcephaly and nervous system malformations.

METHODS

To explore the potential correlation of ZIKV-induced alteration of maternal immunity with fetal abnormalities, we performed extensive sera immunoprofiling of 74 pregnant women: 30 symptomatic ZIKV+ pregnant patients and 30 healthy pregnant controls in ZIKV-endemic Rio de Janeiro, along with 14 healthy pregnant controls in non-endemic Los Angeles.

RESULTS

Extensive multiplexing analysis of 69 cytokines revealed that CXCL10, CCL2, and CCL8 chemokines were specifically associated with symptomatic ZIKV+ infection during pregnancy, and distinct immunoprofiles were detected at different trimesters in ZIKV-infected pregnant women. Intriguingly, the high CCL2 level and its inverse correlation with CD163, TNFRSF1A, and CCL22 levels was apparently associated with ZIKV-induced abnormal birth.

CONCLUSIONS

Our findings provide insights into the alteration of ZIKV-elicited maternal immunity, serving as a potential clinical biomarker platform.

BACKGROUND

NIH (CA200422, CA180779, DE023926, AI073099, AI116585, AI129496, AI140705, AI069120, AI056154, AI078389, AI28697, AI40718 and AI129534-01), Hastings Foundation, Fletcher Jones Foundation, Departamento de Ciência e Tecnologia (DECIT/25000.072811/2016-17) do Ministério da Saúde do Brasil, and Coordenação de Aperfeiçoamento de Pessoal de Nivel Superior CAPES/88887.116627/2016-01.

BACKGROUND

Obesity negatively impacts asthma control, but the inflammatory mechanisms are poorly understood.

OBJECTIVE

To explore which systemic inflammatory mediators mediate the effects of obesity on asthma control.

METHODS

The subjects with stable asthma (n = 108) underwent assessment of clinical characteristics, which included usingThe Asthma Control Questionnaire (ACQ)-6. Obesity was defined as a body mass index (BMI) of more than or equal to 30 kg/m2, overweight was defined as BMI between 25 to 29.9 kg/m2, and lean weight was defined as BMI < 25 kg/m2. Body composition, including fat mass (FM), visceral fat area (VFA), and percentage body fat (PBF) was analyzed by bioimpedance. Serum interleukin (IL) 4, IL-5, IL-8, IL-13, IL-17, chemokine (C-C motif) ligand (CCL) 17, CCL22, leptin, adiponectin, C-reactive protein (CRP), and interferon (IFN) gamma were measured by using ELISA. Linear regression models were fitted according to the Baron and Kenny procedures for mediation analysis.

RESULTS

FM (12.73 +/- 3.95 versus 18.59 +/- 2.95 versus 27.82 +/- 5.17 kg; p < 0.0001), VFA (65.99 +/- 23.17 versus 93.96 +/- 10.28 versus 123.10 +/- 18.34 cm2; p < 0.0001), PBF (23.86 +/- 7.46 versus 30.74 +/- 5.08 versus 36.21 +/- 6.28 %; p = 0.0003)and ACQ-6 values (0.83 [0, 1.17]) versus 1.15 [0.50, 1.75] versus 1.33 [0.83, 1.83] score; p = 0.002) were different amonglean (n = 52), overweight (n = 37), and obese (n = 19) subjects. Serum levels of leptin, IL-5, IL-13, IL-17, CCL17, CRP, andIFN-gamma in the obese group were significantly elevated compared with the subjects who were lean or overweight (all p < 0.05). The mediation analyses found that the effect of obesity, assessed by BMI, on ACQ-6 was significantly mediated throughIL-13 and CCL17. Furthermore, IL-13 and CCL17 mediated the effects of body composition (FM, VFA and PBF) on ACQ-6. The effects of obesity assessed by body composition, but not by using BMI, on ACQ-6 were mediated by leptin.

CONCLUSIONS

Our mediation analysis confirmed that systemic inflammation biomarkers, such as leptin, CCL17, IL-4, andIL-13, mediated the effects of obesity on asthma control. This warrants prospective exploration in this distinct asthma phenotype in the future.

It is well known that bacterial lipopolysaccharide (LPS) induces migration of several cellular populations within the spleen. However, there are no data about the impact of LPS on B and T lymphocytes present in the red pulp. Therefore, we used an experimental model in which we tested the effects of intravenously injected LPS on the molecular, cellular and structural changes of the spleen, with special reference to the red pulp lymphocytes. We discovered that LPS induced a massive relocation of B and T lymphocytes from the splenic red pulp, which was independent of the tumor necrosis factor receptor-1 signaling axis. Early after LPS treatment, quantitative real-time PCR analysis revealed the elevated levels of mRNA encoding numerous chemokines and proinflammatory cytokines (XCL1, CXCL9, CXCL10, CCL3, CCL4, CCL5, CCL17, CCL20, CCL22, TNFα and LTα) which affect the navigation and activities of B and T lymphocytes in the lymphoid tissues. An extreme increase in mRNA levels for CCL20 was detected in the white pulp of the LPS-treated mice. The CCL20-expressing cells were localized in the PALS. Some smaller CCL20-expressing cells were evenly dispersed in the B cell zone. Thus, our study provides new knowledge of how microbial products could be involved in shaping the structure of lymphatic organs.

C-C motif chemokine 22 (CCL22) C16A genetic variation (rs4359426) and C-C chemokine receptor type 4 (CCR4) C1014T variation (rs2228428) have been suggested to affect the expression level of the cognate proteins. Here we tried to investigate the plausible association of these polymorphisms with development of colorectal cancer. 165 patients with colorectal adenocarcinoma (age 54.4±13.4) and 150 age- and sex-matched healthy individuals were enrolled. Genotyping was performed by PCR-RFLP methods. Results indicated the frequency of 16A allele in CCL22 gene to be 31/330(9.4%) and 33/300(11%) in patients and controls, respectively (p=0.59). The frequencies of CC, CA, and AA genotypes at this locus were not significantly different between patients and controls (135/165; 81.8%, 29/165; 17.6%, 1/165; 0.6% in the patients and 121/150; 80.1%, 25/150; 16.6% and 4/150; 2.6% in the control group, p= 0.34). At the locus 1014 in CCR4, T allele was observed with the frequency of 107/330 (32.4%) and 83/300 (27.7%) in patients and controls, respectively (p=0.22). Analyses indicated no significant differences in the frequencies of CC, CT and TT genotypes at this locus between patients and controls (77/165; 46.7%, 69/165; 41.8% and 19/165; 11.5%; versus 83/150; 55.0%, 51/150; 33.8% and 16/150; 10.6%, respectively, p= 0.29). The presence of individual genotypes was not associated with clinicopathological characteristics of the disease, including tumor size, tumor grade and LN involvement (all with p<0.05). These findings collectively suggested that CCR4 C1014T and CCL22 C16A genetic variations were neither associated with the risk, nor with the progression of colorectal cancer in Iranian population.

IL-26 is a potentially important player in host defense and may be a pathogenic factor in the chronic inflammatory disorders of humans. However, the involvement of IL-26 in tuberculous pleural effusion (TPE) has not been investigated. The concentration of IL-26 was determined in pleural fluids and sera from patients with pleural effusions. Flow cytometry was performed to identify the cell origin of IL-26. The effects of tuberculosis-specific antigen (ESAT-6/CFP-10) on IL-26 expression of CD4⁺ T cell were explored. The impacts of IL-26 on modulating CD4⁺ T cell polarization were also investigated. The concentrations of IL-26 were much higher in tuberculous, malignant, and infectious PE than those in the corresponding serum. The expression of IL-26 on CD4⁺ T cells was much higher in tuberculous PE than those in the corresponding serum, and pleural Th1 and Th17 cells might be the major cell sources of IL-26. The addition of ESAT-6/CFP-10 to CD4⁺ T cells led to increasing the number of IL-26-producing CD4⁺ T cells and IL-26 expression on Th1 and Th17 cells. IL-26 could induce the differentiation and generation of IL-22 by memory and naive CD4⁺ T cells. IL-26 also upregulated the mRNA encoding CC-chemokine ligand 20 (CCL20) and CCL22 by mononuclear cells isolated from TPE. This study implies that pleural Th1 and Th17 cells are the major cell sources of IL-26, which could induce the differentiation and generation of Th22 cells by CD4⁺ T cells, suggesting the involvement of IL-26 in the pathogenesis of human TPE. KEY MESSAGES: IL-26 is overexpressed in TPE patients and presents a higher concentration in pleural effusion than the corresponding peripheral blood. Pleural Th1 and Th17 cells might be the major cell sources of IL-26 in TPE patients. IL-26 promotes IL-22 secretion and Th22 generation by CD4⁺ T cells isolated from TPE patients. IL-26 may play an active role in the pathogenesis of tuberculous pleurisy.

BACKGROUND

Airway inflammation is a feature of many respiratory diseases and there is a need for newer, more effective anti-inflammatory compounds. The aim of this study was to develop an ex vivo human lung explant model which can be used to help study the mechanisms underlying inflammatory responses and which can provide a tool to aid drug discovery for inflammatory respiratory diseases such as asthma and COPD.

METHODS

Parenchymal lung tissue from 6 individual donors was dissected and cultured with two pro-inflammatory stimuli, lipopolysaccharide (LPS) (1 µg/ml) and interleukin-1 beta (IL-1β) (10 ng/ml) in the presence or absence of dexamethasone (1 µM). Inflammatory responses were assessed using Luminex analysis of tissue culture supernatants to measure levels of 21 chemokines, growth factors and cytokines.

RESULTS

A robust and reproducible inflammatory signal was detected across all donors for 12 of the analytes measured following LPS stimulation with a modest fold increase (<2-fold) in levels of CCL22, IL-4, and IL-2; increases of 2-4-fold in levels of CXCL8, VEGF and IL-6 and increases >4-fold in CCL3, CCL4, GM-CSF, IL-10, TNF-α and IL-1β. The inflammatory signal induced by IL-1β stimulation was less than that observed with LPS but resulted in elevated levels of 7 analytes (CXCL8, CCL3, CCL4, GM-CSF, IL-6, IL-10 and TNF-α). The inflammatory responses induced by both stimulations was supressed by dexamethasone for the majority of analytes.

CONCLUSIONS

These data provide proof of concept that this ex vivo human lung explant model is responsive to inflammatory signals and could be used to investigate the anti-inflammatory effects of existing and novel compounds. In addition this model could be used to help define the mechanisms and pathways involved in development of inflammatory airway disease.

BACKGROUND

COPD: Chronic Obstructive Pulmonary Disease; ICS: inhaled corticosteroids; LPS: lipopolysaccharide; IL-1β: interleukin-1 beta; PSF: penicillin, streptomycin and fungizone.

A longstanding question is whether neuroinflammation is present in children symptomatic for Tourette syndrome (TS) with positive streptococcal serology and throat cultures. The objective was to directly test for it using modern hypothesis-driven approaches. Profiling studies for 14 immune cell types (flow cytometry), 7 chemokines/cytokines (ELISA), oligoclonal bands, and other immunoglobulins were performed in this IRB-approved study of 5 children with TS and streptococcal markers compared to data from 26 non-inflammatory pediatric neurological controls. Subjects were well-characterized clinically and with standardized scales for tics and obsessions/compulsions. Three subjects with TS (60%) had positive throat cultures for Group A beta-hemolytic strep, five had elevated anti-deoxyribonuclease-B titers (mean=444), and 4 (80%) had elevated anti-streptolysin O titers (981). There were no significant differences between groups in the frequency of CSF B and T cell subsets or NK cells; the proportion of intracellularly-stained T helper type 1 (IFN-γ) or type 2 (IL-4) cells; the concentrations of B cell chemoattractants CXCL13, CXCL10; the B cell proliferation/survival cytokines BAFF and APRIL, or other chemokines (CCL19, CCL21, CCL22). None of the patients had positive CSF oligoclonal bands or an abnormal IgG index/synthesis rate. Parallel blood studies were negative. This novel study found no group CSF lymphocyte phenotypic abnormalities or elevated inflammatory mediators in childhood TS despite positive serology and throat cultures for Group A beta-hemolytic streptococci. It demonstrates feasibility of the methodology, and should serve as the basis for a larger study of putative streptococcal-associated neuroimmunological disorders.

OBJECTIVE

To study the role of Th2-attracting chemokines in opsoclonus-myoclonus syndrome (OMS), a serious neurological paraneoplastic disorder in need of better immunological understanding and therapy.

METHODS

The CCR4 agonists CCL22 and CCL17 were measured in serum by ELISA in children with OMS (238 and 260, respectively), pediatric controls (115 and 143), and other inflammatory neurological disorders (33 and 24).

RESULTS

Both CCL22 (+55 %) and CCL17 (+121 %) were significantly elevated in untreated OMS compared to controls and inter-correlated (p < 0.0001). Their concentrations in untreated OMS also were higher than in OIND (21 %, 41 %). The concentration of CCL22 in ACTH and steroids groups (not IVIg) was 51 % lower than in controls, but only a smaller effect of ACTH on CCL17 was found. Prospective longitudinal studies revealed a precipitous 81 % drop in CCL22 even by the first week of high-dose ACTH therapy, staying below control mean for at least 12 weeks, and a 34 % reduction after 8 months of combined treatment. Response to ACTH was dose-related (r = -0.50, p < 0.0001). Luminex detection confirmed the ELISA results for CCL22, which were about 200 % higher.

CONCLUSIONS

These data reveal an elevated serum concentration of Th2-attracting chemokines CCL22 and CCL17 in OMS. Marked and rapid reduction in CCL22, not CCL17, with either ACTH or steroid therapy suggests differential regulation and cellular sources of CCR4 ligands, and CCL22 as a potential candidate biomarker for ACTH or corticosteroid effect.

The chemokine CCL22 is predominantly produced by dendritic cells (DCs) and macrophages. CCL22 acts on CCR4-expressing cells including Th2 and Treg. Although a correlation between the CCL22-CCR4 axis and allergic diseases has been established, the mechanism of monocyte lineage-specific Ccl22 gene expression is largely unknown. In the current study, we investigated transcriptional regulation of the Ccl22 gene in DCs and macrophages. Using reporter assays, we identified the critical cis-enhancing elements at 21/-18 and -10/-4 in the Ccl22 promoter. Electrophoretic mobility shift assays proved that transcription factor PU.1 directly binds to the cis-elements. Knockdown of PU.1 markedly decreased Ccl22 expression in bone marrow-derived DCs (BMDCs) and BM macrophages (BMDMs). Chromatin immunoprecipitation assays revealed that PU.1 bound to the Ccl22 promoter in not only BMDCs and BMDMs, but also splenic DCs and peritoneal macrophages. LPS stimulation increased the amount of PU.1 recruited to the promoter, accompanied by upregulation of the Ccl22 mRNA level, which was diminished by Spi1 knockdown. We identified similar cis-elements on the human CCL22 promoter, which were bound with PU.1 in human monocytes. Taken together, these findings indicate that PU.1 transactivates the Ccl22 gene in DCs and macrophages by directly binding to the two elements in the promoter.

Objective: To study the role of miR-34c-5p targeting CCL22 in affecting the progression of chronic obstructive pulmonary disease (COPD). Methods: The dual-luciferase reporter gene assay was applied to verify the targeting relationship of miR-34c-5p and CCL22. The rats were randomly assigned into Control, COPD, COPD + empty plasmids, COPD + agomir, COPD + CCL22 shRNA and COPD + agomir + CCL22 groups. COPD model was built by using cigarette smoke exposure and LPS instillation. After 28 days, the pulmonary function was examined. ELISA method was used to detect TNF-α and IL-8 levels in bronchoalveolar lavage fluid (BALF), HE staining and Masson staining to observe the pathomorphological changes of lung tissues, qRT-PCR and/or Western blot to determine miR-34c-5p and CCL22 levels, and immunohistochemical staining to measure the expression of MMP-9 and TIMP-1. Results: MiR-34c-5p could target CCL22 to down-regulate its expression. Both miR-34c-5p agomir and CCL22 shRNA could reduce breathing frequency (f), airway resistance (RI), and the levels of IL-8 and TNF-α in BALF of COPD rats with increased Cydn (dynamic lung compliance) and PIF (peak inspiratory flow). Besides, the inflammatory cell infiltration, rupture of partial alveolus, enlarged alveolar cavity, and increased deposition of collagen fibers were observed in COPD rat tissues, with rise in mean linear intercept (MLI) and reduction in mean alveolar number (MAN), which could be reversed by miR-34c-5p agomir or CCL22 shRNA. Conclusion: MiR-34c-5p may promote inflammation response and maintain the protease-antiprotease balance via targeting CCL22, which provides scientific basis for the clinical treatment of COPD.

BACKGROUND

There is a medical need for new drugs in patients with BRAF wild-type metastatic melanoma. Pazopanib is a multitarget tyrosine kinase inhibitor with antitumour and antiangiogenic activity.

OBJECTIVE

The primary aim was to investigate the metabolic response to pazopanib monotherapy and pazopanib plus paclitaxel in patients with BRAF wild-type melanoma. Secondary end points were the early cytokine and chemokine profiles and histological findings.

METHODS

Pazopanib (400 mg twice daily) was administered orally from days 1 to 10 and from days 14 to 70. An intravenous infusion with paclitaxel (150 mg m-2 body surface) was administered on days 14, 35 and 56. Metabolic response evaluation was performed before treatment, after treatment with pazopanib (day 10) and after treatment with pazopanib and paclitaxel (day 70). Skin biopsy of metastatic tissue for chemokine and cytokine expression analysis and histology and immunohistochemistry (CD68, CD163) evaluation, and blood samples were taken at the same time points.

RESULTS

Two patients failed screening and 17 were dosed. Of 67 adverse events, nine (13%) were grade 3 or 4. Five of 14 evaluable patients had a partial metabolic response at day 10 under pazopanib monotherapy. The response rate at day 70 under combined pazopanib-paclitaxel treatment was 0%. Immunohistochemistry revealed an increase of M2-like macrophages in nonresponders compared with responders. We observed a significant upregulation of five cytokines (CXCL1, CXCL2, CXCL13, CCL22 and SPP1) in responding vs. nonresponding lesions. Overall, the median progression-free survival was 70 days (range 5-331), which did not differ significantly between responders (148 days) and nonresponders (70 days, P = 0·17).

CONCLUSIONS

In this patient population pazopanib efficacy was limited. Response is associated with low M2-like macrophage density and increased expression of several chemokines.

T helper (Th)22 and Th17 cells are implicated in the pathogenesis of a number of types of cancer. However, the function of Th22 and Th17 cells in malignant ascites (MA) remains unknown. The present study aimed at examining the distribution, phenotypes, recruitment, and prognostic value of Th22 and Th17 cells in MA from patients with hepatocellular carcinoma (HCC). A total of 26 patients with HCC with MA and 15 healthy controls were included in the present study. The proportion of Th22 cells, Th17 cells, C-C motif chemokine receptor (CCR)4, CCR6 and CCR10 were examined using flow cytometry. Interleukin (IL-)22, IL-17, C-C motif chemokine ligand (CCL)20, CCL22 and CCL27 were investigated using ELISA. In addition, the chemoattractant activity of chemokines for Th22 and Th17 cells in vitro were examined via a chemotaxis assay. The results of the present study demonstrated that Th22 cells, Th17 cells, IL-22 and IL-17 were significantly increased in MA compared with the corresponding blood and peripheral blood from healthy controls. Additionally, Th22 cells expressed increased concentrations of CCR6, CCR4 and CCR10, and Th17 cells expressed increased concentrations of CCR4 and CCR6 in MA compared with the corresponding blood. The chemotaxis assay revealed that CCL20/CCR6, CCL22/CCR4 and CCL27/CCR10 were responsible for the recruitment of Th22 cells into MA, whereas CCL22/CCR4 was responsible for the recruitment of Th17 cells. Furthermore, the patients with an increased number of Th17 cells exhibited an increased survival time compared with patients with a limited number of Th17 cells. Th22 and Th17 cells serve an important function in the development of MA, and the accumulation of Th22 and Th17 cells in MA may be due to a local increase in proinflammatory cytokines and chemokines. Increased Th17 cell numbers in MA may indicate the improvement of patient survival.

Prostaglandin D2 (PGD2) is a prostanoid implicated in allergic inflammation. However, the roles of PGD2 in immune and allergic responses remain controversial. PGD2 exerts its effect through the CRTH2 and DP receptors. To elucidate functional differences of PGD2 and its receptors in chronic skin inflammation, chronic contact hypersensitivity (chronic CHS) and IgE-mediated chronic allergic skin inflammation (IgE-CAI) were induced in mice deficient in the CRTH2 and/or DP genes. DP (-/-) mice and CRTH2 (-/-)/DP (-/-) mice showed exacerbated chronic CHS, and conversely, CRTH2 (-/-) mice exhibited diminished skin responses. Skin responses correlated with local levels of IL-13, CCL11, and CCL22. These phenotypic changes in chronic CHS of mutant mice were similar to those in acute CHS despite the differences in the cytokine milieus; chronic CHS and acute CHS were mediated by Th2 and Th1/Th17 immunity, respectively. However, in IgE-CAI, DP (-/-) mice showed comparable skin responses to wild-type mice. Alleviation of IgE-CAI was observed in CRTH2 (-/-) mice, and as a consequence, CRTH2 (-/-)/DP (-/-) mice exhibited diminished IgE-CAI compared with wild-type mice. IgE-CAI in mutant mice correlated with local IL-4 and CCL22 production. Consistent with these results, a CRTH2-specific antagonist exerted inhibitory effects in both chronic CHS and IgE-CAI. The present study demonstrates that functional roles of PGD2 and its receptors appear to depend on the nature of the inflammation. Nevertheless, tools targeted against PGD2-CRTH2 signals could offer therapeutic potential for both types of chronic skin inflammation.

Neisseria meningitidis colonizes the nasopharyngeal mucosa of healthy populations asymptomatically, although the bacterial surface is rich in motifs that activate the host innate immunity. What determines the tolerant host response to this bacterium in asymptomatic carriers is poorly understood. We demonstrated that the conserved meningococcal surface protein NhhA orchestrates monocyte (Mo) differentiation specifically into macrophage-like cells with a CD200R(hi) phenotype (NhhA-Mφ). In response to meningococcal stimulation, NhhA-Mφ failed to produce proinflammatory mediators. Instead, they upregulated interleukin-10 (IL-10) and Th2/regulatory T cell (Treg)-attracting chemokines, such as CCL17, CCL18, and CCL22. Moreover, NhhA-Mφ were highly efficient in eliminating bacteria. The in vivo validity of these findings was corroborated using a murine model challenged with N. meningitidis systematically or intranasally. The NhhA-modulated immune response protected mice from septic shock; Mo/Mφ depletion abolished this protective effect. Intranasal administration of NhhA induced an anti-inflammatory response, which was associated with N. meningitidis persistence at the nasopharynx. In vitro studies demonstrated that NhhA-triggered Mo differentiation occurred upon engaged Toll-like receptor 1 (TLR1)/TLR2 signaling and extracellular signal-regulated kinase (ERK) and Jun N-terminal protein kinase (JNK) activation and required endogenously produced IL-10 and tumor necrosis factor alpha (TNF-α). Our findings reveal a strategy that might be adopted by N. meningitidis to maintain asymptomatic nasopharyngeal colonization.

OBJECTIVE

Neisseria meningitidis is an opportunistic human-specific pathogen that colonizes the nasopharyngeal mucosa asymptomatically in approximately 10% of individuals. Very little is known about how this bacterium evades immune activation during the carriage stage. Here, we observed that N. meningitidis, via the conserved surface protein NhhA, skewed monocyte differentiation into macrophages with a CD200R(hi) phenotype. Both in vivo and in vitro data demonstrated that these macrophages, upon meningococcal infection, played an important role in forming a homeostatic immune microenvironment through their capacity to eliminate invading bacteria and to generate anti-inflammatory mediators. This work provides novel insight into the mechanisms underlying the commensal persistence of N. meningitidis.

Macrophage phenotype and function varies according to their polarized state, which in turn is dependent on microenvironmental stimuli. Under normal physiological conditions, lung interstitial macrophages that express interleukin (IL)-10 are considered to serve regulatory roles in the prevention of allergic reactions in the airways. However, the phenotypic profile of lung interstitial macrophages during the pathophysiology of asthma remains unknown. In the current study, the phenotypic characteristics of lung interstitial macrophages were investigated in an ovalbumin (OVA)-induced mouse model of asthma. The patterns of surface markers chemokine ligand and interleukin, and the metabolic enzyme activity of lung interstitial macrophages were investigated using flow cytometry analysis, reverse transcription-quantitative polymerase chain reaction, western blot analysis, and ELISA. It was observed that lung interstitial macrophages derived from OVA-induced asthmatic mice expressed phenotypic markers associated with alternatively activated macrophages (M2), including cluster of differentiation-206, transglutaminase 2, arginase (Arg) 1 and chemokine ligand (CCL)17/CCL22/CCL24 secretion. The M2 macrophages also exhibited increased levels of Arg1 activity and reduced levels of IL-10 expression, relative to macrophages derived from control mice. However, when evaluating the expression of markers associated with classically activated (M1) macrophages, namely inducible nitric oxide synthase and IL-12, it was observed that levels of M1 markers in the interstitial macrophages from asthmatic mice did not differ significantly to those in controls. Collectively, these data suggest that lung interstitial macrophages undergo a phenotypic switch from a regulatory macrophage phenotype under normal conditions to an alternative activation state in OVA-induced asthmatic mice.