title: Innate immunity is sufficient for the clearance of Chlamydia trachomatis from the female mouse genital tract.
abstract: Chlamydia muridarum and Chlamydia trachomatis, mouse and human strains, respectively, have been used to study immunity in a murine model of female genital tract infection. Despite evidence that unique genes of these otherwise genomically similar strains could play a role in innate immune evasion in their respective mouse and human hosts, there have been no animal model findings to directly support this conclusion. Here, we infected C57BL/6 and adaptive immune-deficient Rag1(-/-) female mice with these strains and evaluated their ability to spontaneously resolve genital infection. Predictably, C57BL/6 mice spontaneously cleared infection caused by both chlamydial strains. In contrast, Rag1(-/-) mice which lack mature T and B cell immunity but maintain functional innate immune effectors were incapable of resolving C. muridarum infection but spontaneously cleared C. trachomatis infection. This distinct dichotomy in adaptive and innate immune-mediated clearance between mouse and human strains has important cautionary implications for the study of natural immunity and vaccine development in the mouse model.
authors.affiliation: Laboratory of Intracellular Parasites, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, USA.
authors.forename: Gail L
authors.initials: GL
authors.lastname: Sturdevant
authors.forename: Harlan D
authors.initials: HD
authors.lastname: Caldwell
mesh_terms: D000818:Animals; D002690:Chlamydia Infections / Q000276:immunology*; D023502:Chlamydia muridarum / Q000276:immunology; D002692:Chlamydia trachomatis / Q000276:immunology*; D004195:Disease Models, Animal; D005260:Female; D005836:Genitalia, Female / Q000276:immunology* / Q000382:microbiology*; D007113:Immunity, Innate; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D060737:Reproductive Tract Infections / Q000276:immunology*
keywords: Chlamydiae; Rag−/− mice; adaptive immunity; female genital tract; human and mouse strains; innate immunity