Jordan, Stephen J.Gupta, KanupriyaOgendi, Brian M. O.Bakshi, Rakesh K.Kapil, RichaPress, Christen G.Sabbaj, SteffanieLee, Jeannette Y.Geisler, William M.2017-12-082017-12-082017-04Jordan, S. J., Gupta, K., Ogendi, B. M., Bakshi, R. K., Kapil, R., Press, C. G., ... & Geisler, W. M. (2017). The Predominant CD4+ Th1 Cytokine Elicited to Chlamydia trachomatis Infection in Women Is Tumor Necrosis Factor Alpha and Not Interferon Gamma. Clinical and Vaccine Immunology, 24(4), e00010-17. http://dx.doi.org/10.1128/CVI.00010-17https://hdl.handle.net/1805/14770Chlamydia trachomatis infection is the most prevalent bacterial sexually transmitted infection and can cause significant reproductive morbidity in women. There is insufficient knowledge of C. trachomatis-specific immune responses in humans, which could be important in guiding vaccine development efforts. In contrast, murine models have clearly demonstrated the essential role of T helper type 1 (Th1) cells, especially interferon gamma (IFN-γ)-producing CD4+ T cells, in protective immunity to chlamydia. To determine the frequency and magnitude of Th1 cytokine responses elicited to C. trachomatis infection in humans, we stimulated peripheral blood mononuclear cells from 90 chlamydia-infected women with C. trachomatis elementary bodies, Pgp3, and major outer membrane protein and measured IFN-γ-, tumor necrosis factor alpha (TNF-α)-, and interleukin-2 (IL-2)-producing CD4+ and CD8+ T-cell responses using intracellular cytokine staining. The majority of chlamydia-infected women elicited CD4+ TNF-α responses, with frequency and magnitude varying significantly depending on the C. trachomatis antigen used. CD4+ IFN-γ and IL-2 responses occurred infrequently, as did production of any of the three cytokines by CD8+ T cells. About one-third of TNF-α-producing CD4+ T cells coproduced IFN-γ or IL-2. In summary, the predominant Th1 cytokine response elicited to C. trachomatis infection in women was a CD4+ TNF-α response, not CD4+ IFN-γ, and a subset of the CD4+ TNF-α-positive cells produced a second Th1 cytokine.enIUPUI Open Access PolicyChlamydia trachomatisTh1 responsestumor necrosis factorArticle