Figure 4.

Effect of levonorgestrel (LNG) on T-helper type 1 (Th1)/Th2 polarization during infection. Vaginal swab specimens were collected weekly for cytokine analysis. Baseline values represent the cytokine environment immediately before infection and were compared to cytokine values 1 week after infection. Animals that received the LNG-releasing intrauterine system (LNG-IUS) had induction of the primarily Th2-recruiting chemokine CCL2 (MCP-1) during the week after initial inoculation (ie, at week 1; A), while the non-LNG group had induction of the primarily Th1-recruiting chemokine CCL3 (MIP-1α) at week 1 (B). Week 0 corresponds to the baseline (uninfected) state. Data are for 6–7 animals per sample (some points are superimposed). *P < .05; **P < .01.