Regulatory T cells in pregnancy. IV. Genetic characteristics and mode of action of early MLR suppressive T cell subpopulations.

The genetic characteristics, surface markers, and mechanisms of action of early-acting, mitomycin-resistant, MLR suppressor T cells from multiparous mouse spleens were studied in MLR of various strain combinations. The cell activity appears to be genetically restricted at the suppressor/reactive cell level, and the major restriction occurs via the IC subregion. However, C3H.OL recombinant pointed toward a possible minor requirement for S-G subregion syngenicity. The suppressor T cell was characterized as an Ia+, Ly1-, Ly2+ subset. The use of Karush double chambers as well as of supernatants of regulated MLR provided evidence that the suppressor cells act via soluble product(s).