Interleukin 2, production in the syngeneic mixed lymphocyte reaction

In the syngeneic mixed lymphocyte reaction, Ly 1 cells proliferate following stimulation with Ia-positive macrophage-like cells. The proliferation is accompanied by the release of interleukin 2 into the medium. Both the proliferation and interleukin 2 production are dependent on the expression of Ia antigenic determinants, as the addition of haplotype-specific anti-Ia antisera to the cultures inhibits both parameters.