FIG. 3.

A C. trachomatis-specific CD8⁺-T-cell clone which recognizes C. trachomatis in association with HLA-B27. (A) IFN-γ production in response to C. trachomatis-infected autologous PBMC and two HLA-matched allo-PBMC. C1 PBMC were matched for HLA-A2 and HLA-B27, while C2 PBMC were matched for HLA-A2 but were HLA-B27 negative. (B) IFN-γ production by a C. trachomatis-specific CD8⁺-T-cell clone in the presence of w6/32, ME1 (anti-HLA-B27), and MA2.1 (anti-HLA-A2) antibodies. (C and D) Specific lysis of C. trachomatis-infected and uninfected U937-A2 target cells and of C. trachomatis-infected U937-B27 alone or in the presence of w6/32, ME1, or MA2.1. Each experiment was repeated three times. CT, C. trachomatis.