Corynebacterium liquefaciens-induced suppressor T cells in graft-versus-host reaction

The effect of the spleen cells and thymus cells from Corynebacterium liquefaciens-treated (C57BL/6 x BALB/c)F1 hybrid mice on graft-versus-host (GVH) reaction, initiated in the parental to newborn F1 hybrid strain combination, was studied by using Simonsen's spleen assay. The combined inocula of 5 x 10(6) normal BALB/c spleen cells and 50 x 10(6) spleen cells from F1 mice that had been given i.v. injections of 1 mg of C. liquefaciens yielded a significantly smaller spleen index than did 5 x 10(6) BALB/c spleen cells alone. This suppressive function of C. liquefaciens-treated F1 spleen cells was more potent in phagocyte-depleted and T cell-enriched cell fractions. Thymus cells from C. liquefaciens-treated F1 mice also suppressed GVH reaction. The results suggest that C. liquefaciens can induce the suppressor T cells.