Ondondo RO, et al. - Researchers evaluated cytokine responses on PBMCs obtained from men with persistent or cleared human papillomavirus (HPV) in order to assess cell-mediated immune responses to natural HPV infections in men. Heightened odds (6-times and 3-times respectively) of mounting cytokine responses were observed in men with HPV clearance and those with HPV persistence vs HPV uninfected men. In men with HPV clearance vs HPV uninfected men, the significant upregulation of Th1 cytokines IFN-γ (5.1-fold) and IL-2 (4.2-fold) was noted. A significant upregulation of only IFN-γ (2.4–fold) and IL-2 (3.0–fold) was found in men with HPV clearance vs those with persistent HPV infection. Findings revealed a link between Th1 cell-mediated cytokine response and natural HPV clearance in men.