OBJECTIVE

Matrix metalloproteinase-8 (MMP-8) is a central mediator in chronic periodontitis. Recently developed MMP-8-deficient mice show an impaired polymorphonuclear neutrophil response and more severe alveolar bone loss in Porphyromonas gingivalis-induced experimental periodontitis. The main mediators involved in neutrophil and monocyte/macrophage recruitment and in bone loss include lipopolysaccharide-induced CXC chemokine (LIX/CXCL5), stromal-derived factor-1/CXC chemokine ligand 12 (SDF1/CXCL12) and RANKL. Therefore, the aim of this study was to characterize the expression of LIX/CXCL5, SDF1/CXCL12 and RANKL in Porphyromonas gingivalis-induced experimental periodontitis in MMP-8⁻/⁻ (knockout) and wild-type mice.

METHODS

MMP-8 null and WT P. gingivalis-infected and uninfected mice were included. Histopathological changes were assessed and LIX/CXCL5, SDF1/CXCL12 and RANKL were immunodetected and quantified.

RESULTS

Typical histopathological features of chronic periodontitis were seen in P. gingivalis-infected groups. LIX/CXCL5 expression was restricted to the gingival papilla in all four groups. Significantly lower expression of LIX/CXCL5 was seen in the knockout group compared with the wild-type infected group (p < 0.05). SDF1/CXCL12 and RANKL expression was mainly localized to the alveolar crest, including inflammatory leukocytes, vascular endothelium, osteoblasts and osteoclasts. Significant increases of SDF1/CXCL12 and RANKL were seen in both knockout and wild-type P. gingivalis-infected groups compared with uninfected groups (p < 0.05).

CONCLUSIONS

RANKL and SDF1/CXCL12 are up-regulated in P. gingivalis-induced periodontitis and they appear to be associated with the pathogenesis of the disease. MMP-8 is associated with a reduced expression of LIX/CXCL5 in the P. gingivalis-induced experimental periodontitis model.

Repeated exposure to welding fumes promotes a reversible increase in pulmonary disease risk, but the molecular mechanisms by which welding fumes induce lung injury and how the lung recovers from such insults are unclear. In the present study, pulmonary function and gene-expression profiles in the lung were analyzed by Affymetrix GeneChip microarray after 30 days of consecutive exposure to manual metal arc welding combined with stainless-steel (MMA-SS) welding fumes, and again after 30 days of recovery from MMA-SS fume exposure. In total, 577 genes were identified as being either up-regulated or down-regulated (over twofold changes, p < 0.05) in the lungs of low-dose or high-dose groups. Differentially expressed genes were classified based on a k-means clustering algorithm and biological functions and molecular networks were further analyzed using Ingenuity Pathways Analysis. Among the genes affected by exposure to or recovery from MMA-SS fumes, the transcriptional changes of 13 genes that were highly altered by treatment were confirmed by quantitative real-time PCR. Notably, Mmp12, Cd5l, Ccl7, Cxcl5, and Spp1 related to the immune response were up-regulated only in the exposure group, whereas Trem2, IgG-2a, Igh-1a, and Igh were persistently up-regulated in both the exposure and recovery groups. In addition, several genes that might play a role in the repair process of the lung were up-regulated exclusively in the recovery group. Collectively, these data may help elucidate the molecular mechanism of the recovery process of the lung after welding fume exposure.

Reactivation of the human polyomavirus JC (JCV) in the CNS results in a fatal demyelinating disease, progressive multifocal leukoencephalopathy (PML). The lytic destruction of oligodendrocytes, which occurs at the terminal stage of the viral infection cycle, is considered a critical factor in the development of demyelination and the pathogenesis of PML. However, knowledge is limited about interaction of JCV with oligodendrocytes and its impact on the denudation of axons at the early stage of viral reactivation and prior to the destruction of the infected cells. We have developed an in vitro neuroprogenitor cell culture using human fetal brain that can be differentiated to the oligodendrocyte lineage to investigate interactions of JCV with its host cells. Results show that infection with JCV delays oligodendrocyte maturation as shown by reduced levels of oligodendrocytic markers, including myelin basic protein, proteolipid protein, and platelet-derived growth factor receptor-α. Furthermore, replication of JCV in these cells caused substantial dysregulation of several chemokines, including CCL5/RANTES, GRO, CXCL1/GROα, CXCL16, CXCL8/IL-8, CXCL5/ENA-78, and CXCL10/IP-10, all of which play a role in cell growth and differentiation.

Helicobacter pylori infection systematically causes chronic gastric inflammation that can persist asymptomatically or evolve toward more severe gastroduodenal pathologies, such as ulcer, mucosa-associated lymphoid tissue (MALT) lymphoma, and gastric cancer. The cag pathogenicity island (cag PAI) of H. pylori allows translocation of the virulence protein CagA and fragments of peptidoglycan into host cells, thereby inducing production of chemokines, cytokines, and antimicrobial peptides. In order to characterize the inflammatory response to H. pylori, a new experimental protocol for isolating and culturing primary human gastric epithelial cells was established using pieces of stomach from patients who had undergone sleeve gastrectomy. Isolated cells expressed markers indicating that they were mucin-secreting epithelial cells. Challenge of primary epithelial cells with H. pylori B128 underscored early dose-dependent induction of expression of mRNAs of the inflammatory mediators CXCL1 to -3, CXCL5, CXCL8, CCL20, BD2, and tumor necrosis factor alpha (TNF-α). In AGS cells, significant expression of only CXCL5 and CXCL8 was observed following infection, suggesting that these cells were less reactive than primary epithelial cells. Infection of both cellular models with H. pylori B128ΔcagM, a cag PAI mutant, resulted in weak inflammatory-mediator mRNA induction. At 24 h after infection of primary epithelial cells with H. pylori, inflammatory-mediator production was largely due to cag PAI substrate-independent virulence factors. Thus, H. pylori cag PAI substrate appears to be involved in eliciting an epithelial response during the early phases of infection. Afterwards, other virulence factors of the bacterium take over in development of the inflammatory response. Using a relevant cellular model, this study provides new information on the modulation of inflammation during H. pylori infection.

Endothelial inflammation with chemokine involvement contributes to acute coronary syndromes (ACS). We tested the hypothesis that variation in the chemokine gene CXCL5, which encodes epithelial neutrophil-activating peptide (ENA-78), is associated with ACS prognosis. We also investigated whether statin use, a potent modulator of inflammation, modifies CXCL5's association with outcomes and characterized the in vitro effect of atorvastatin on endothelial ENA-78 production. Using a prospective cohort of ACS patients (n = 704) the association of the CXCL5 -156 G>C polymorphism (rs352046) with 3-year all-cause mortality was estimated with hazard ratios (HR). Models were stratified by genotype and race. To characterize the influence of statins on this association, a statin*genotype interaction was tested. To validate ENA-78 as a statin target in inflammation typical of ACS, endothelial cells (HUVECs) were treated with IL-1beta and atorvastatin with subsequent quantification of CXCL5 expression and ENA-78 protein concentrations. C/C genotype was associated with a 2.7-fold increase in 3-year all-cause mortality compared to G/G+G/C (95%CI 1.19-5.87; p = 0.017). Statins significantly reduced mortality in G/G individuals only (58% relative risk reduction; p = 0.0009). In HUVECs, atorvastatin dose-dependently decreased IL-1beta-stimulated ENA-78 concentrations (p<0.0001). Drug effects persisted over 48 hours (p<0.01). CXCL5 genotype is associated with outcomes after ACS with potential statin modification of this effect. Atorvastatin lowered endothelial ENA-78 production during inflammation typical of ACS. These findings implicate CXCL5/ENA-78 in ACS and the statin response.

Aside from its mechanical barrier function, bronchial epithelium plays an important role both in the host defense and in the pathogenesis of inflammatory airway disorders. To investigate its role in lung defense, the effect of a bacterial cell wall protein, the outer membrane protein A from Klebsiella pneumoniae (kpOmpA) on bronchial epithelial cells (BEC) was evaluated on adhesion molecule expression and cytokine production. Moreover, the potential implication of this mechanism in kpOmpA-induced lung inflammation was also determined. Our in vitro studies demonstrated that kpOmpA strongly bound to BEAS-2B cells, a human BEC line, and to BEC primary cultures, resulting in NF-kappaB signaling pathway activation. Exposure to kpOmpA increased ICAM-1 mRNA and cell surface expression, as well as the secretion of IL-6, CXC chemokine ligand (CXCL)1, CXCL8, C-C chemokine ligand 2, CXCL10 by BEAS-2B cells, and BEC primary cultures (p < 0.005). We analyzed in vivo the consequences of intratracheal injection of kpOmpA to BALB/c mice. In kpOmpA-treated mice, a transient neutrophilia (with a maximum at 24 h) was observed in bronchoalveolar lavage and lung sections. In vivo kpOmpA priming induced bronchial epithelium activation as evaluated by ICAM-1 and CXCL1 expression, associated with the secretion of CXCL1 and CXCL5 in bronchoalveolar lavage fluids. In the lung, an increased level of the IL-6, CXCL1, CXCL5, CXCL10 mRNA was observed with a maximum at 6 h. These data showed that kpOmpA is involved in host defense mechanism by its ability to activate not only APC but also BEC, resulting in a lung neutrophilia.

LPS-induced CXC chemokine (LIX) is a murine chemokine similar to two human chemokines, ENA-78 (CXCL5) and GCP-2 (CXCL6). To clarify the relationship of LIX to human ENA-78 and GCP-2, we cloned and mapped the LIX gene. The organization of the LIX gene ( Scyb5) is similar to those of the human ENA-78 ( SCYB5) and GCP-2 ( SCYB6) genes. The intron-exon boundaries of the three genes are exactly conserved, and the introns have similar sizes. The first 100 bp of the 5' flanking regions are highly similar, with conserved NF-kappaB and GATA sites in identical positions in all three genes. Further 5', the Lix flanking region sequence diverges from those of ENA-78 and GCP-2, which remain highly similar for 350 bp preceding the start sites. Using a (C57BL/6 J x Mus spretus) F1 x C57BL/6J backcross panel, Lix was mapped to a locus near D5Ucla5 at 49.0 cM on Chromosome (Chr) 5. Mapping with the T31 radiation hybrid panel placed Lix between D5Mit360 and D5Mit6. Physical maps of the CXC chemokine clusters on murine Chr 5 and human Chr 21 were constructed using the Celera mouse genome database and the public human genome database. The sequence and mapping data suggest that the human ENA78-PBP-PF4 and GCP2- psi PBP-PF4V1 loci arose from an evolutionarily recent duplication of an ancestral locus related to the murine Lix-Pbp-Pf4 locus.

BACKGROUND

Adaptive villus growth after a massive small bowel resection (SBR) is an important response to the loss of intestinal surface area and is regulated via epidermal growth factor receptor (EGFR) signaling. Increased levels of the proangiogenic chemokine ligand 5 (CXCL5) have been found within the adapting bowel in which angiogenesis is increased. We sought to determine whether CXCL5 was expressed specifically in the villus mesenchymal zone (area of increased blood vessel growth) and whether this expression was affected by EGF.

METHODS

C57BL/6J mice were subjected to sham operation (bowel transaction with reanastomosis) or 50% proximal SBR. The remnant intestine was harvested, and the villus lamina propria was isolated by laser capture microdissection. The expression of CXCL5 messenger RNA (mRNA) was analyzed using real-time polymerase chain reaction (RT-PCR). Furthermore, CXCL5 mRNA levels were determined in EGF-stimulated human umbilical vein endothelial cells (HUVECs).

RESULTS

A 2.39-fold increase (P < .05) in CXCL5 mRNA occurred in the lamina propria after SBR. In addition, villus height was found to be related directly to the degree of CXCL5 mRNA (R(2) = 0.97) expression. HUVECs treated with EGF demonstrated a 9-fold increase in CXCL5 mRNA expression.

CONCLUSIONS

The villus growth observed in resection-induced adaptation is associated with increased expression of the chemokine CXCL5 within the lamina propria. Because EGF enhances CXCL5 expression directly in endothelial cells, EGFR-directed proangiogenic gene expression may be a critical mechanism for adaptive ileal villus growth.

BACKGROUND

Chemokines play important roles in cancer development and progression. Epithelial-derived neutrophil-activating peptide-78 (ENA78/CXCL5) and stromal cell-derived factor (SDF-1/CXCL12) supposedly contribute to gastric cancer (GC) development and progression. This study aims to evaluate serum levels of ENA78/CXCL5 and SDF-1/CXCL12 along the GC carcinogenesis, and analyze their clinical significance, and diagnostic potentials through human serum samples.

METHODS

A total of 300 subjects were enrolled in this study. Serum levels of ENA78/CXCL5 and SDF-1/CXCL12, measured by chemiluminescent immunoassay, were compared among 4 disease groups; normal, high-risk (intestinal metaplasia and adenoma), early GC (EGC), and advanced GC (AGC) groups in both training (n=25 per group) and validation dataset (n=70, 30, 50, 50, respectively) by ANOVA test (post hoc Bonferroni). Correlations between serum ENA78/CXCL5 or SDF-1/CXCL12 levels and clinicopathological parameters of GC patients were evaluated (Spearman's correlation; γs). To validate the diagnostic accuracy, receiver operating characteristic (ROC) curve and logistic regression analysis was performed.

RESULTS

Serum ENA78/CXCL5 and SDF-1/CXCL12 levels were significantly higher in AGC groups than EGC, high-risk and normal groups in both training and validation dataset (Bonferroni, from p<0.01 to p<0.001). Clinicopathologically, serum ENA78/CXCL5 was correlated with T-stage (γs=0.231, p=0.021) and distant metastasis (γs=0.357, p<0.001), while serum SDF-1/CXCL12 was correlated with lymph node (γs=0.220, p=0.029) and distant (γs=0.425, p<0.001) metastasis. ROC curve and logistic regression demonstrated that serum ENA78/CXCL5 and SDF-1/CXCL12 showed higher diagnostic accuracy compared with carcinoembryonic antigen (CEA) in predicting GC. Serum ENA78/CXCL5 could predict both the presence of GC and distant metastasis, while serum SDF-1/CXCL12 could mainly predict its distant metastasis. All combination of serum ENA78/CXCL5, SDF-1/CXCL12, and CEA achieved 92.8% specificity at 75.0% sensitivity to predict distant metastasis of GC.

CONCLUSIONS

Combinations of initial serum ENA78/CXCL5, SDF-1/CXCL12, and CEA before any treatment for GC can produce valuable serum biomarker panels to predict the presence and distant metastasis of GC.

Chlorine is a toxic gas used in a variety of industrial processes and is considered a chemical threat agent. High-level chlorine exposure causes acute lung injury, but the long-term effects of acute chlorine exposure are unclear. Here we characterized chronic pulmonary changes following acute chlorine exposure in mice. A/J mice were exposed to 240 parts per million-hour chlorine or sham-exposed to air. Chlorine inhalation caused sloughing of bronchial epithelium 1 day after chlorine exposure, which was repaired with restoration of a pseudostratified epithelium by day 7. The repaired epithelium contained an abnormal distribution of epithelial cells containing clusters of club or ciliated cells rather than the uniformly interspersed pattern of these cells in unexposed mice. Although the damaged epithelium in A/J mice was repaired rapidly, and minimal airway fibrosis was observed, chlorine-exposed mice developed pneumonitis characterized by infiltration of alveoli with neutrophils and prominent, large, foamy macrophages. Levels of CXCL1/KC, CXCL5/LPS-induced CXC chemokine, granulocyte colony-stimulating factor, and VEGF in bronchoalveolar (BAL) fluid from chlorine-exposed mice showed steadily increasing trends over time. BAL protein levels were increased on day 4 and remained elevated out to day 28. The number of bacteria cultured from lungs of chlorine-exposed mice 4 wk after exposure was not increased compared with sham-exposed mice, indicating that the observed pneumonitis was not driven by bacterial infection of the lung. The results indicate that acute chlorine exposure may cause chronic abnormalities in the lungs despite rapid repair of injured epithelium.

BACKGROUND

The incidence and prevalence of both benign prostatic hypertrophy (BPH) and prostate cancer (PCa) increase with the aging process. Our laboratory recently showed that the chemokines CXCL5 and CXCL12, which normally function as inflammatory mediators, are secreted at higher levels by aging prostate stromal fibroblasts and elicit proliferative responses from both prostate stromal fibroblast and epithelial cells. Because both CXCL5 and CXCL12 are secreted molecules, we hypothesized that their levels in patient serum might serve as biomarkers to distinguish between BPH and PCa.

METHODS

Serum CXCL5 and CXCL12 levels were determined using sandwich ELISAs for 51 men demonstrating low serum PSA values of < or =10 ng/ml who underwent diagnostic needle biopsy for the detection of PCa. The bivariate relationship of circulating chemokine levels, age, and disease status in the prostate was tested using the Wilcoxon rank-sum test.

RESULTS

Total serum CXCL12 levels were significantly higher for men who were biopsy positive compared to those who were biopsy negative for cancer and histological prostatitis (P = 0.050). Among men who were biopsy negative for PCa, total serum CXCL5 levels were inversely associated with prostate volume and were significantly higher in men with concomitant BPH and histological prostatitis compared to those without evidence of prostatic disease (P < 0.003).

CONCLUSIONS

The results of this pilot and feasibility study suggest that serum or plasma CXCL5 and CXCL12 levels may potentially distinguish between BPH and PCa among patients presenting with low serum PSA, and may be useful toward facilitating decisions to perform diagnostic needle biopsy in this patient population.

CXCL5 (epithelial-cell-derived neutrophil-activating protein (ENA-)78) is a CXC-chemokine that specifically acts on neutrophils. To obtain insight into the extent of local presence and action of CXCL5 during bacterial meningitis, we measured its concentrations in cerebrospinal fluid (CSF) of patients with culture-proven bacterial meningitis (n=14), aseptic meningitis (n=6), and controls (n=32) and compared these results with levels of other CXC-chemokines, CXCL8- (interleukin-8) and CXCL1-related oncogene (growth-related oncogene (GRO)-alpha). Patients with bacterial meningitis had profoundly elevated CSF concentrations of all three chemokines. CXCL5 was not detectable in patients with aseptic meningitis or control subjects. CSF from patients with bacterial meningitis exerted chemotactic activity towards neutrophils, which was partially inhibited by neutralizing antibodies against CXCL5 and CXCL8, but not CXCL1. CSF from controls exerted minor chemotactic activity, which could be strongly enhanced by the addition of recombinant CXCL5, CXCL8 or CXCL1. During bacterial meningitis, CXCL5 is elevated in CSF, where it is involved in the recruitment of neutrophils to the central nervous system.

BACKGROUND

Transforming growth factor (TGF)-beta is an important modulator of immune functions and cellular responses, such as differentiation, proliferation, migration and apoptosis. The Smad proteins, which are intracellular TGF-beta signal transducers, mediate most actions of TGF-beta.

OBJECTIVE

This study examines the role of Smad3 in a murine model of contact hypersensitivity (CHS).

METHODS

The CHS response to oxazolone was studied in Smad3-deficient mice. The ear swelling response was measured and skin biopsies from oxazolone-sensitized skin areas were obtained for RNA isolation, immunohistochemical analyses and histology. Ear draining lymph nodes were collected for RNA isolation and proliferation tests. Quantitative real-time polymerase chain reaction was used to quantify mRNA expression of cytokines, chemokines and transcription factors. Results The expression of proinflammatory [interleukin (IL)-1beta, tumour necrosis factor-alpha, IL-6], Th2 (IL-4) and Th17 type cytokines (IL-17), as well as regulatory components (TGF-beta, Foxp3) increased significantly at the mRNA level in the skin of oxazolone-treated Smad3-/- mice when compared with wild-type controls. The expression of the Th1 type cytokine IFN-gamma and the chemokines CXCL9 and CXCL10 was, however, unaffected by the lack of Smad3. The number of neutrophils and expression of the chemokines CCL3 and CXCL5, which are both involved in neutrophil recruitment, were increased in mice lacking Smad3. Also Th2 type chemokines CCL24, CCL3 and CXCL5 were increased in the skin of Smad3-/- mice compared with wild-type mice. In the lymph nodes, mRNA of IL-1beta and IL-17, but not IL-4, TGF-beta or Foxp3, was increased in Smad3-/- mice during the CHS response.

CONCLUSIONS

The lack of intact TGF-beta signalling via Smad3 results in an increased proinflammatory, Th2 and Th17 type response in the skin, as well as increased expression of regulatory elements such as TGF-beta and Foxp3. Understanding the role of Smad3 in the CHS response may offer treatment and prevention strategies in this often disabling disease.

BACKGROUND

Protease-Activated Receptors (PARs), members of G-protein-coupled receptors, are activated by proteolytic activity of various proteases. Activation of PAR1 and PAR2 triggers innate immune responses in human oral keratinocytes (HOKs), but the signaling pathways downstream of PAR activation in HOKs have not been clearly defined. In this study, we aimed to determine if PAR1- and PAR2-mediated signaling differs in the induction of innate immune markers CXCL3, CXCL5 and CCL20 via ERK, p38 and PI3K/Akt.

RESULTS

Our data show the induction of innate immunity by PAR1 requires both p38 and ERK MAP kinases, while PAR2 prominently signals via p38. However, inhibition of PI3K enhances expression of innate immune markers predominantly via suppressing p38 phosphorylation signaled by PAR activation.

CONCLUSIONS

Our data indicate that proteases mediating PAR1 and PAR2 activation differentially signal via MAP kinase cascades. In addition, the production of chemokines induced by PAR1 and PAR2 is suppressed by PI3K/Akt, thus keeping the innate immune responses of HOK in balance. The results of our study provide a novel insight into signaling pathways involved in PAR activation.

The emergence of chemoresistance greatly increases the recurrence risk for non-muscle invasive bladder cancer (NMIBC) patients, which is still a big concern of clinicians. Understanding the mechanisms of drug resistance is of great significance for preventing and reversing it. We showed here that CXC motif chemokine ligand 5 (CXCL5) was overexpressed in mitomycin C-resistant bladder cancer cell line M-RT4. Meanwhile, parental RT4 cell treated with recombinant human CXCL5 (rhCXCL5) reduced its sensitivity to mitomycin C. Conversely, knockdown CXCL5 sensitized M-RT4 cell. We further investigated the molecular mechanisms finding that epithelial mesenchymal transition (EMT) and NF-κB pathway were activated in M-RT4 cell, which could be attenuated by knockdown CXCL5. All these data indicated that CXCL5 may promote mitomycin resistance by activating EMT and NF-κB pathway. Thus, our study identifies CXCL5 as a novel chemoresistance-related marker in NMIBC, thereby providing new strategies to overcome chemoresistance for NMIBC patients.

Myocardial infarction (MI) is identified as one of the major causes of mortality and disability worldwide. For severe myocardial infarction, even advanced forms of clinical intervention often lead to unsatisfactory therapeutic results. Thus, alternative strategies for MI treatment are still desirable. Previously studies reported the capacity of degradative fragment of h-HA (high molecular weight hyaluronic acid), hyaluronan oligosaccharides (<10 disaccharides units, o-HA), for wound healing by influence on angiogenesis, inspiring us to study its potential for myocardial functional recovery against MI. However, there are few reports about o-HA in MI therapy. Methods: In our study, we synthesized o-HA with 6~10 disaccharides (4-5 kDa) by enzymatic degradation and investigated its therapeutic effects on MI. Results: We found that o-HA could reduce infarct size and apoptosis in MI region, also promote myocardial angiogenesis and myocardial function reconstruction in MI mouse model. Furthermore, our results also indicated that o-HA in cardiac improved polarization of M2 type macrophage, removed the inflammatory response caused by neutrophil for accelerating myocardial function reconstruction in vivo. The transcriptomic analyses revealed that o-HA could activate expression of chemokines Ccl2 and Cxcl5 for promoting macrophage polarization and stimulate MAPK and JAK/STAT signaling pathway for compensatory response of myocardial function. Conclusion: Collectively, our results suggested o-HA with 6~10 disaccharides might be a potential agent for reconstruction of cardiac function against MI.

Inflammatory factors play a vital role in the progression of liver cancer, although exact factors and related mechanisms still remain unclear. The present study aimed at screening inflammatory factors related to liver cancer metastasis and investigating the potential mechanism by which cancer cells are recruited. We screened and validated inflammatory factors by microarray and RT-PCR. Small interfering RNA (siRNA) and recombinant protein were used to assess CXCL5 effects on the movement of liver cancer cells (LCCs). Our screening microarray demonstrated over-expression of CXCL5 in LCCs with high metastatic potentials. CXCL5 increased LCCs migration and invasion, probably through autocrine and paracrine mechanisms. CXCL5-CXCR2 and ERK1/2 pathways could play critical roles in the regulation of LCCs migration. Our data indicates that LCCs per se may act as the producer and receptor of CXCL5 responsible for liver cancer migration and invasion.

Sex differences in the incidence of respiratory diseases have been reported. Women are more susceptible to inflammatory lung disease induced by air pollution and show worse adverse pulmonary health outcomes than men. However, the mechanisms underlying these differences remain unknown. In the present study, we hypothesized that sex differences in the expression of lung inflammatory mediators affect sex-specific immune responses to environmental toxicants. We focused on the effects of ground-level ozone, a major air pollutant, in the expression and regulation of lung immunity genes. We exposed adult male and female mice to 2 ppm of ozone or filtered air (control) for 3 h. We compared mRNA levels of 84 inflammatory genes in lungs harvested 4 h postexposure using a PCR array. We also evaluated changes in lung histology and bronchoalveolar lavage fluid cell counts and protein content at 24 and 72 h postexposure. Our results revealed sex differences in lung inflammation triggered by ozone exposure and in the expression of genes involved in acute phase and inflammatory responses. Major sex differences were found in the expression of neutrophil-attracting chemokines (Ccl20, Cxcl5, and Cxcl2), the proinflammatory cytokine interleukin-6, and oxidative stress-related enzymes (Ptgs2, Nos2). In addition, the phosphorylation of STAT3, known to mediate IL-6-related immune responses, was significantly higher in ozone-exposed mice. Together, our observations suggest that a differential regulation of the lung immune response could be implicated in the observed increased susceptibility to adverse health effects from ozone observed in women vs. men.

BACKGROUND

Many studies have demonstrated that chemokines and their receptors play important roles in breast cancer. However, few of them focus on the concentration change of chemokines along breast cancer evolvement, especially for primary breast cancer.

OBJECTIVE

To investigate the effects of chemokines and their receptors on different stage of primary breast cancer, and to find correlationships between chemokines, between different clinico-pathological characters of patients or between chemokines and different clinico-pathological characters of patients.

METHODS

We evaluated and compared the concentration of 10 chemokines and receptors in serum of patients diagnosed as breast benign change, epithelial proliferation (present only or with atypia), in situ carcinoma and invasive carcinoma.

RESULTS

Our oneway ANOVA analysis results showed that in all cases from benign diseases to invasive carcinoma, the concentration of CXCL8, CXCR4 and CXCL12 was significantly different; in benign subgroups (benign change, benign change with proliferation, atypia), the concentration of CCL2 and CCR5 was significantly different; in invasive carcinoma cases, DARC concentration was significantly correlated with the relapse risk of patients.

CONCLUSIONS

The correlation analysis indicated the great crosstalk between chemokines and receptors in the course of primary breast cancer; Ki67 expression was associated with CXCL5 and CXCL7 concentration; tumor size was associated with CXCL8 concentration; and the correlation analysis between clinico-pathological characters of patients showed that pathological diagnosis was correlated with tumor size, relapse risk and Ki67 expression; nuclear grades was correlated with LN metastasis, ER status, PR status and the breast cancer genotype; LN metastasis was correlated with relapse risk. Our findings clearly indicated for the first time that the fluctuations of chemokines and receptors contributed to the evolving of primary breast cancer.

COPD is characterized by an ongoing inflammatory process of the airways that leads to obstruction or limitation of airflow. It is mainly associated with exposure to cigarette smoke. In addition, it is considered, at present, a serious public health problem, ranking fourth in mortality worldwide. Many cells participate in the pathophysiology of COPD, the most important are neutrophils, macrophages and CD4+ and CD8+ T cells. Neutrophil migration to the inflammation area could be mediated largely by cytokines related to CD4+ Th17 lymphocytes, because it has been shown that IL-17A, IL-17F and IL-22 act as inducers for CXCL8, CXCL1, CXCL5, G-CSF, and GM-CSF secretion by epithelial cells of the airways. The aims of these molecules are differentiation, proliferation and recruitment of neutrophils. Furthermore, it is believed that CD4+ lymphocytes Th17 may be involved in protection against pathogens for which Th1 and Th2 are not prepared to fight. In COPD exacerbations, there is an increased cellularity in the lung region and respiratory tract. Therefore, the increase in the number of neutrophils and macrophages in the airways and the increase in proinflammatory cytokines are directly related to the severity of exacerbations and that is the importance of the functions of Th17 profile in this entity.

Systemic Candida albicans infection causes high morbidity and mortality and is now the leading cause of nosocomial bloodstream infection in the United States. Neutropenia is a major risk factor for poor outcome in infected patients; however, the molecular factors that mediate neutrophil trafficking and effector function during infection are poorly defined. Using a mouse model of systemic candidiasis, we found that the neutrophil-selective CXC chemokine receptor Cxcr1 and its ligand, Cxcl5, are highly induced in the Candida-infected kidney, the target organ in the model. To investigate the role of Cxcr1 in antifungal host defense in vivo, we generated Cxcr1(-/-) mice and analyzed their immune response to Candida. Mice lacking Cxcr1 exhibited decreased survival with enhanced Candida growth in the kidney and renal failure. Increased susceptibility of Cxcr1(-/-) mice to systemic candidiasis was not due to impaired neutrophil trafficking from the blood into the infected kidney but was the result of defective killing of the fungus by neutrophils that exhibited a cell-intrinsic decrease in degranulation. In humans, the mutant CXCR1 allele CXCR1-T276 results in impaired neutrophil degranulation and fungal killing and was associated with increased risk of disseminated candidiasis in infected patients. Together, our data demonstrate a biological function for mouse Cxcr1 in vivo and indicate that CXCR1-dependent neutrophil effector function is a critical innate protective mechanism of fungal clearance and host survival in systemic candidiasis.

The TH17 immune response has a central role in the pathogenesis of autoimmune diseases, implicating the TH17 master cytokine, IL-17A, as the critical mediator of diseases such as human and experimental crescentic GN. However, the relative importance of additional TH17 effector cytokines, including IL-17F, in immune-mediated tissue injury remains to be fully elucidated. Here, using a mouse model of acute crescentic GN (nephrotoxic nephritis), we identified CD4+ T cells and γδ T cells as the major cellular source of IL-17F in the inflamed kidney. Interventional studies using IL-17F gene-deficient mice, IL-17F-neutralizing antibodies, and adoptive transfer experiments into Rag1-/- mice demonstrated that CD4+ T cell-derived IL-17F drives renal tissue injury in acute crescentic GN. Notably, IL-17F-deficient nephritic mice had fewer renal infiltrating neutrophils than wild-type nephritic mice, and neutrophil depletion did not affect the course of GN in IL-17F-deficient mice. Moreover, in the chronic model of pristane-induced SLE, IL-17F-deficient mice developed less severe disease than wild-type mice, with respect to survival and renal injury. Finally, we show that IL-17F induced expression of the neutrophil-attracting chemokines CXCL1 and CXCL5 in kidney cells. The finding that IL-17F has a nonredundant function in the development of renal tissue injury in experimental GN might be of great importance for the development of anti-IL-17 cytokine therapies in TH17-mediated human autoimmune diseases.

BACKGROUND

Late-term pregnancy may lead to maternal and neonatal morbidity and mortality. Mice null for the progesterone receptor co-regulator Krüppel-like Factor 9 (KLF9) exhibit delayed parturition and increased incidence of neonatal deaths.

OBJECTIVE

Our aim is to evaluate the contribution of myometrial KLF9 to human parturition.

METHODS

Myometrial biopsies were obtained from women with term (>37 to ≤41 wk) and late-term (>41 wk) pregnancies during cesarean delivery and assessed for gene and protein expression. Human myometrial cells transfected with nontargeting or KLF9 small interfering RNAs (siRNA) were treated with the progesterone antagonist RU486 and analyzed for pro-inflammatory chemokine/cytokine gene expression.

METHODS

The study took place in a University-affiliated tertiary care hospital and University research laboratory.

METHODS

Term patients (n = 8) were in spontaneous active labor whereas late-term patients (n = 5) were either in or were induced to active labor, prior to elective cesarean delivery.

METHODS

Steroid hormone receptor, contractility, and inflammation-associated gene expression in myometrial biopsies and in siKLF9-transfected, RU486-treated human myometrial cells was associated with KLF9 expression levels.

RESULTS

Myometrium from women with late-term pregnancy showed lower KLF9, total PGR, and PGR-A/PGR-B isoform expression. Transcript levels of select chemokines/cytokines were up- (CSF3, IL1, IL12A, TGFB2) and down- (CCL3, CCL5, CXCL1, CXCL5, IL15) regulated in late-term relative to term myometrium. Knock-down of KLF9 expression in RU486-treated human myometrial cells modified the expression of PGR and labor-associated cytokines, relative to control siRNA-treated cells.

CONCLUSIONS

Myometrial KLF9 may contribute to the onset of human parturition through its regulation of PGR expression and inflammatory signaling networks.

BACKGROUND

Neuroinflammation accompanies neural trauma and most neurological diseases. Axotomy in the peripheral nervous system (PNS) leads to dramatic changes in the injured neuron: the cell body expresses a distinct set of genes known as regeneration-associated genes, the distal axonal segment degenerates and its debris is cleared, and the axons in the proximal segment form growth cones and extend neurites. These processes are orchestrated in part by immune and other non-neuronal cells. Macrophages in ganglia play an integral role in supporting regeneration. Here, we explore further the molecular and cellular components of the injury-induced immune response within peripheral ganglia.

METHODS

Adult male wild-type (WT) and Ccr2 -/- mice were subjected to a unilateral transection of the sciatic nerve and axotomy of the superior cervical ganglion (SCG). Antibody arrays were used to determine the expression of chemokines and cytokines in the dorsal root ganglion (DRG) and SCG. Flow cytometry and immunohistochemistry were utilized to identify the cellular composition of the injury-induced immune response within ganglia.

RESULTS

Chemokine expression in the ganglia differed 48 h after nerve injury with a large increase in macrophage inflammatory protein-1γ in the SCG but not in the DRG, while C-C class chemokine ligand 2 was highly expressed in both ganglia. Differences between WT and Ccr2 -/- mice were also observed with increased C-C class chemokine ligand 6/C10 expression in the WT DRG compared to C-C class chemokine receptor 2 (CCR2)-/- DRG and increased CXCL5 expression in CCR2-/- SCG compared to WT. Diminished macrophage accumulation in the DRG and SCG of Ccr2 -/- mice was found compared to WT ganglia 7 days after nerve injury. Interestingly, neutrophils were found in the SCG but not in the DRG. Cytokine expression, measured 7 days after injury, differed between ganglion type and genotype. Macrophage activation was assayed by colabeling ganglia with the anti-inflammatory marker CD206 and the macrophage marker CD68, and an almost complete colocalization of the two markers was found in both ganglia.

CONCLUSIONS

This study demonstrates both molecular and cellular differences in the nerve injury-induced immune response between DRG and SCG and between WT and Ccr2 -/- mice.