Production and main characteristics of a fetal calf serum-specific cell line that induces T and B cell differentiation

Spleen cells from B6 mice injected with fetal calf serum (FCS) could be kept proliferating as a continuous cell line in vitro provided they were culture in the presence of irradiated syngeneic spleen cells and FCS. Cells in this cell line showed a strong proliferative response when stimulated with concanavalin A (Con A), and they were able to mediate the following functions: (1)they helped the generation of alloantigen-specific cytotoxic T lymphocytes (CTL) from thymocyte-spleen cell mixed lymphocyte cultures (MLC), (2)they induced the generation of CTL from normal syngeneic spleen cells in the absence of allogeneic stimulator cells, and (3)they induced normal spleen cells to differentiate into anti-sheep erythrocyte (SRBC) plaque-forming cells (PFC), in the absence of SRBC in the cultures. The use of this cell line (called line 12) may thus provide an interesting approach for the study of cellular and molecular requirements for cell-cell interactions and for the differentiation of T and B effector functions.