Immune mechanisms in chlamydial eye infection. Development of T suppressor cells

In vitro proliferation assays of whole peripheral blood mononuclear leukocytes (PBML) and PBML depleted of suppressor T cells were performed in cynomolgus monkeys after they had received one, two, or repeated ocular inoculations with Chlamydia trachomatis. Whole PBML responded only weakly to chlamydial antigen, and responses to concanavalin A were depressed for 12 wk following ocular infection. Depletion of the suppressor T cell population did not result in increased chlamydia-specific proliferation until 14-20 wk after initial antigen contact, suggesting that circulating suppressor T cells are not responsible for the initiation of the chronic state.