EVIDENCE FOR A PREDOMINANT PROINFLAMMATORY CONJUNCTIVAL CYTOKINE RESPONSE IN INDIVIDUALS WITH TRACHOMA

Immune responses to Chlamydia trachomatis infection in trachoma do not protect against reinfection or the development of scarring and blindn ess, Tn addition, the immunoregulatory contribution of cytokines to th e development of conjunctival histopathology or protection is undefine d. In this study, conjunctival cytokine mRNA transcripts were compared among subgroups of chlamydia infection status and ocular disease pres entations of 50 individuals from an area where trachoma is endemic, Th ere was a significant association of elevated interleukin (IL)-1 beta, transforming growth factor beta 1, and tumor necrosis factor alpha tr anscripts with infection, follicular inflammation, and scarring, Both gamma interferon (IFN-gamma) and IL-2 transcripts were significantly a ssociated with infection; slightly elevated IL-2 levels were found in inflammatory disease, High IFN-gamma transcript levels were present wi th follicles and inflammatory disease and to a lesser extent with infl ammatory scarring, The role of IFN-gamma in protection from infection or disease was not apparent from this study, since transcripts were fr equently present in both chlamydial infection and disease, IL-12 (p40) transcripts were elevated in adults and children in association with follicular inflammation but not with scarring, IL-4, IL-5, and IL-10 t ranscripts were not detected in any samples, In conclusion, C. trachom atis infection stimulates local cytokines which favor a strong cell-me diated and proinflammatory response in both the early and later manife stations of trachoma. In addition, cytokine transcript levels that wer e associated with disease but no infection were characteristically low er overall than when chlamydia was present.