Ly-6 A/E antigen of murine T cells is associated with a distinct pathway of activation. Requirements for interferon and exogenous interleukin 2.

The Ly-6 pathway of T cell activation was analyzed to identify its essential requirements. Using a monospecific chicken antiserum to Ly-6E, fully cross-reactive to its allelic counterpart, Ly-6A, but unreactive with other members of the Ly-6 family, we have found that interferon (IFN)-alpha/beta or gamma, Ly-6 antibody and interleukin 2 (IL 2) act synergistically in inducing T cell proliferation. The action of IFN can be attributed to induction of Ly-6A/E antigen on T cells, as described previously, and this induction is transcriptionally controlled.

Bidirectionality of mixed lymphocyte stimulation (Mls) response. Effects of Mlsb stimulator cells on Mlsa helper cells.

The activation of BALB/c lymphocytes in the mixed lymphocyte reaction to Mls-disparate APC has been shown to encompass up to 20% of the mature resting helper T lymphocyte population. In addition to these overtly Mls-responsive cells, our studies have revealed a second population that respond to the Mls difference of DBA/2 spleen cells in conjunction with the mitogen Con A. This part of the Mls response is therefore latent.