Hapten-specific human T cell lines. I. Functional analysis with respect to cytotoxic and helper activity.

Human PBL cells, sensitized in vitro to TNP or FITC-modified autologous stimulators, have been successfully grown in long-term culture by using TCGF derived from PHA-activated tonsil cells. Long-term cultures consist almost exclusively of T lymphocytes as defined by the formation of spontaneous rosettes with sheep erythrocytes and C-mediated lysis with heteroantibodies to human T cells (R alpha T H). The majority, but not all of these T cells, bear surface Ia antigens as detected by C-mediated lysis in the presence of alpha p23,30. Functionally, these cultures maintain high levels of hapten-specific cytolytic activity during many weeks of culture. In addition, a number of these T cell lines exhibit hapten specific proliferation when co-cultured with x-irradiated hapten modified autologous cells. During this proliferative response, helper factor(s) are released that trigger B cell differentiation into AFC. Data are presented that demonstrate that helper factor(s) production by T cell line cells is preferentially triggered by autologous, but nt allogeneic stimulator cells, bearing the relevant hapten.