ROLE FOR CD8(-CELLS IN ANTICHLAMYDIAL IMMUNITY DEFINED BY CHLAMYDIA-SPECIFIC T-LYMPHOCYTE CLONES() T)

The role of CD8(+). T cells in antichlamydial immunity was investigate d in a murine model of chlamydial genital infection by using T-cell cl ones generated against the Chlamydia trachomatis agent of mouse pneumo nitis (MoPn). Two CD8(+) T-cell clones tested (2.1F and 2.14-9) were c hlamydia antigen specific and MHC restricted and reacted against MoPn as well as the Chlamydia psittaci agent of guinea pig inclusion conjun ctivitis and C. trachomatis serovar E, suggesting the recognition of a genus-specific antigen. Upon adoptive transfer into persistently MoPn -infected nu/nu mice, 55.6% of the recipients of clone 2.1F (15 of 27) resolved the infection but recipients of clone 2.14-9 did not. The ab ility to resolve the MoPn infection correlated with the capacity of cl one 2.1F to elaborate a combination of gamma interferon and tumor necr osis factor alpha. The results suggested that in addition to CD4(+) T cells, CD8(+) T cells may also contribute to anti-chlamydial T-cell im munity in vivo.