HERPES-VIRUS SAIMIRI-TRANSFORMED HUMAN T-LYMPHOCYTES - NORMAL FUNCTIONAL PHENOTYPE AND PRESERVED T-CELL RECEPTOR SIGNALING

Herpes virus saimiri (HVS), a primate herpes virus, transforms human C D4+ and CD8+ T lymphocytes to continuous growth in vitro. We have prev iously shown that HVS-transformed human T cells (HVS-T cells) respond to stimulation via CD2 with autocrine growth. In the present study we have investigated the functional characteristics of HVS-T cells. We de scribe that these cells can perform all the functions of normal T cell s, i.e. cytokine secretion, cytotoxicity, and exocytosis of granule es terases. All these activities can be triggered via CD2 by binding to i ts natural ligand or via the TCR, e.g. by anti-TCR antibodies, by reco gnition of a bacterial superantigen and by MHC-restricted recognition of specific antigen. The pattern of tyrosine-phosphorylated proteins a fter TCR triggering was identical in HVS-T cells and normal T cells. W e conclude that HVS-T cells can respond to TCR-mediated signals with t he functions of normal T lymphocytes. Furthermore, HVS-T cells are the only transformed human T cells that can be specifically triggered by cytotoxicity and esterase release. The finding that the TCR functions normally in these cells will make HVS a convenient means to immortaliz e antigen-specific human T lymphocytes.