title: Critical role of the interleukin-17/interleukin-17 receptor axis in regulating host susceptibility to respiratory infection with Chlamydia species.
abstract: The specific contribution of interleukin-17/interleukin-17 receptor (IL-17/IL-17R)-mediated responses in regulating host susceptibility against obligatory intracellular Chlamydia infection was investigated in C57BL/6 and C3H/HeN mice during Chlamydia muridarum respiratory infection. We demonstrated that Chlamydia stimulated IL-17/IL-17R-associated responses in both Chlamydia-resistant C57BL/6 and Chlamydia-susceptible C3H/HeN mice. However, C3H/HeN mice developed a significantly greater IL-17/IL-17R-associated response than C57BL/6 mice did. This was reflected by an increase in IL-17 mRNA expression, a higher recall IL-17 production from splenocytes upon antigen restimulation, and higher production of Th17-related cytokines (IL-23 and IL-6) and chemokines (chemokine [C-X-C motif] ligand 2 [CXCL1]/keratinocyte-derived chemokine [KC] and CXCL2/macrophage inflammatory protein 1 [MIP2]) in C3H/HeN mice than in C57BL/6 mice. Furthermore, C3H/HeN mice displayed a massive accumulation of activated and preactivated neutrophils in the airway and lung parenchyma compared to their C57BL/6 counterparts. We further demonstrated that the skewed IL-17/Th17 profile in C3H/HeN mice was predisposed by a higher basal level of IL-17 receptor C (IL-17RC) expression and then further amplified by a higher inducible IL-17RA expression in lungs. Most importantly, in vivo delivery of IL-17RA antagonist that resulted in a 50% reduction in the neutrophilic infiltration in lungs was able to reverse the susceptible phenotype of C3H/HeN mice to respiratory Chlamydia infection. Thus, our data for the first time have demonstrated a critical role for the IL-17/IL-17R axis in regulating host susceptibility to Chlamydia infection in mice.
authors.affiliation: Canadian Center for Vaccinology, Department of Microbiology and Immunology, Dalhousie University, Research & Clinical Care Pavilion, 3rd Floor West, 5850/5980 University Avenue, Halifax, Nova Scotia B3K 6R8, Canada.
authors.forename: Xiaohui
authors.initials: X
authors.lastname: Zhou
authors.forename: Qiangwei
authors.initials: Q
authors.lastname: Chen
authors.forename: Jessica
authors.initials: J
authors.lastname: Moore
authors.forename: Jay K
authors.initials: JK
authors.lastname: Kolls
authors.forename: Scott
authors.initials: S
authors.lastname: Halperin
authors.forename: Jun
authors.initials: J
authors.lastname: Wang
mesh_terms: D000818:Animals; D002689:Chlamydia / Q000276:immunology; D002690:Chlamydia Infections / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D016207:Cytokines / Q000096:biosynthesis / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D020381:Interleukin-17 / Q000276:immunology* / Q000378:metabolism; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D053722:Receptors, Interleukin-17 / Q000276:immunology* / Q000378:metabolism; D012141:Respiratory Tract Infections / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016176:T-Lymphocyte Subsets / Q000276:immunology*
chemical_list: D016207:Cytokines; D020381:Interleukin-17; D053722:Receptors, Interleukin-17