FIG. 1.

Effect of dose on the distribution of CD4⁺ and IFN-γ-producing Th1 cells within the genital tract. (A) FACS profiles of CD4⁺ cells in CV and OD tissues 7 days postinfection from one representative experiment. Percentages of CD4⁺ cells were calculated from lymphocytes gated by forward- and side-scatter analysis. (B) Number of CD4⁺ cells in CV and OD tissues per 10⁶ genital tract cells during the onset of adaptive immunity (days 7 and 14). Data are compiled from two to three independent experiments. There were statistically greater numbers of CD4⁺ cells on day 14 compared to day 7 for all doses (*, P = 0.01 by two-way ANOVA). (C) Chlamydia-responsive Th1 cells were identified by intracellular cytokines IFN-γ (+) and IL-4 (−) within gated CD4⁺ CD69⁺ lymphocytes. (D) Number of Th1 cells in CV and OD tissues per 10⁶ genital tract cells. Data are compiled from two independent experiments.