T cell responses to 60/65 kDa heat shock protein derived peptides in Turkish patients with Behcet's disease

Objective. Sequence homology and cross reactivity between microbial and hum an heal shuck proteins (HSP) led to the concept that HSP might be involved in the etiopathogenesis of Behcet's disease (BD). We investigated T cell re sponses to 8 synthetic peptides derived from the mycobacterial 65 kDa and h omologous human 60 kDa HSP in patients with BD. Methods, T cell proliferative responses to synthetic peptides were studied in 49 patients with BD and 46 disease (DC) and 34 healthy controls (HC) wit h H-3-thymidine uptake test. Results, Positive T cell responses to one or more of the mycobacterial pept ides were observed in 52% (12/23) of patients with BD compared with 17% (3/ 18) of DC (p = 0.02) and to homologous human peptides in 57% (13/23) of BD and 11% (2/18) of DC (p < 0.01). Responses to the mixtures of 4 mycobacteri al peptides were also significantly higher in BD compared with controls (st imulation index in BD 4.7 +/- 3.5 vs DC 2.0 +/- 1.7, HC 16 +/- 0.4: BD vs D C and HC, p < 0.001). Similar elevated responses es to the mixture of 4 hum an peptides was also observed in patients with BD (BL) 3.4 +/- 2.3: DC 1.9 +/- 0.8; HC 1.4 +/- 0.6, BD vs DC, p < 0.01; BD vs HC, p < 0.001). Conclusion. These results suggest that cellular immunity against the 65 kDa mycobacterial and 60 kDa human HSP derived peptides is significantly incre ased in Turkish patients with RD compared to controls, as observed in the U K and Japan.