Generation of phenotypically different T cell populations by cell-free or cell-bound preparations of varicella zoster virus.

We used three different preparations of varicella zoster virus (VZV) to sensitise mononuclear cells obtained from VZV immune donors. These were autologous infected fibroblasts, live cell free virus and heat inactivated cell free virus. After 14 days of in vitro sensitisation and expansion with interleukin-2, the mononuclear cells which had been exposed to autologous infected fibroblasts had generated mainly cells of the cytotoxic/suppressor phenotype (CD8) while those stimulated with cell free virus (live or heat inactivated) had generated cells of the helper/inducer phenotype (CD4). Functional assays showed that the effector cells generated after exposure to autologous infected fibroblasts lysed autologous virus infected target cells but not uninfected cells. Effector cells generated in the same way but lacking HLA identity with the virus infected target cells failed to demonstrate cytotoxicity. None of these effector cells showed any significant natural killer cell activity. No specific cytotoxicity was obtained by effector cells generated after exposure to cell-free virus. We conclude that the way in which VZV antigen is presented to the mononuclear cells influences the cell type responding in tissue culture. These findings would be useful in the generation of T cell clones of different cell surface phenotype and function.