MELANOMA SPECIFIC TH1 CYTOTOXIC T-LYMPHOCYTE LINES IN VOGT-KOYANAGI-HARADA-DISEASE

Aims/background - To determine the functional properties and cytokine production profiles of melanoma specific cytotoxic T lymphocytes (CTLs ) induced from peripheral blood leucocytes of two patients with Vogt-K oyanagi-Harada disease (VKH). Methods - Melanoma specific CTL lines we re established by long term coculture with a human melanoma cell Line (P-36). Cytotoxic activity against P-36 was measured by Cr-51 release. The involvement of human leucocyte antigen (HLA) class I or class II molecules in the cytotoxicity of the CTL lines against P-36 was analys ed using anti-HLA class I or anti-HLA class II monoclonal antibody (MA b). Surface molecules of CTL lines were analysed by flow cytometry usi ng MAbs specific for CD4, CD8, CD16, CD25, CD56, HLA-DR, T cell antige n receptor (TCR) alpha beta and TCR gamma delta. Cytokine production a nd soluble interleukin 2 receptor (sIL-2R) secretion were determined b y enzyme linked immunosorbent assays. mRNAs of cytokines were analysed using reverse transcription polymerase chain reaction (RT-PCR). Resul ts - CTLs showed strong cytotoxic activity against P-36. The CTL activ ity of the cell lines against P-36 was inhibited by the anti-HLA-DR MA b, whereas the MAb specific for monomorphic determinants of HLA-A, B, and C failed to block lytic activity. Flow cytometry identified the fo llowing surface molecules: CD4(+), CD8(-), CD16(-), CD25(+), CD56(-), HLA-DR(+), TCR alpha beta(+), and TCR gamma delta(-). CTLs constitutiv ely produced a high level of IL-6. IL-6 production and sIL-2R secretio n of CTLs were enhanced when CTLs were stimulated with P-36. CTLs also produced high levels of interferon gamma (IFN-gamma) and IL-2, but no t IL-4. mRNAs of IL-2 and IFN-gamma were detected by RT-PCR in the CTL s. Conclusions - Melanoma specific HLADR restricted T helper 1 (Th1) C TLs may play a role in the immunopathogenesis of VKH.