Generation of homogeneous populations of alloreactive T cells in vitro.

The supernatant from Con A-activated spleen cells (CS) can be used to generate homogenous populations of alloreactive T cells in vitro. Subculture of activated cells in CS containing medium is required for the continued proliferation and expression of effector activity. Prolonged subculture in CS containing medium does not result in indefinite growth and proliferation of alloreactive T cells. The activity in CS required to maintain cytotoxic cell growth is not species specific, and is therefore separable from the costimulator activity in CS required for the initiation of the T cell response to alloantigen; this latter activity is species specific.