CD3-dependent lymphocyte activation by human T cell leukaemia virus type I-producing T cells

Human T cell leukaemia virus type I-(HTLV-I) transformed cells are capable of stimulating the proliferation of normal T lymphocytes, or stimulating interleukin 2 expression in Jurkat T lymphoid cells. This effect is mediated by the CD2/lymphocyte function-associated antigen 3 (LFA-3) adhesion/signalling pathway. The current work demonstrates that CD3 is also required for this effect, suggesting that the T cell receptor (TCR)/CD3 complex is mediating this effect. However, this effect does not appear to be due to a superantigen since no change in TCR expression was found after HTLV-I-mediated proliferation, nor was proliferation inhibited by an antibody against the specific TCR expressed on Jurkat cells (TCR V beta 8).