CONJUNCTIVAL SCARRING IN TRACHOMA IS ASSOCIATED WITH DEPRESSED CELL-MEDIATED IMMUNE-RESPONSES TO CHLAMYDIAL ANTIGENS

In vitro responses of peripheral blood mononuclear cells (PBMC) were m easured to antigens of Chlamydia trachomatis in 29 subjects with sever e conjunctival scarring and compared with responses from 29 age-, sex- , and location-matched controls from a trachoma-endemic area in The Ga mbia. Proliferative and interferon-gamma responses were measured again st chlamydial elementary bodies, recombinant major outer membrane prot ein, and affinity-purified recombinant chlamydial heat shock protein 6 0. Serum antibody levels in response to these antigens were also compa red between the two groups, and the presence of ocular chlamydial anti gen and DNA was assessed. PBMC from donors with conjunctival scarring had reduced proliferative responses to chlamydial antigens but not con trol antigens or mitogens compared with matched controls. By contrast, subjects with scarring had significantly higher levels of anti-chlamy dial IgG antibody compared with matched controls and were more likely to be harboring ocular chlamydial antigen or DNA (or both).