Partial tolerant state against H-2 disparate cells. No impaired specific reactivity in MLC, GVH, or antibody production.

Injection of CBA mice with H-2-compatible lymphoid cells from C3H hybrids induces a specific reduction of the mixed lymphocyte culture (MLC) response of their lymphoytes. This is not the case after injection of H-2-disparate C3H-hybrid cells, presumably because they are rapidly eliminated due to the immune response of the host. This investigation shows that CBA mice injected with CBA X C57Bl cells (H-2-disparate) at an age of 0-3 days, but not older, develop a specifically reduced MLC response after infusion of C3H X C57Bl cells as adults, indicating that they were tolerant to the C57Bl-determined antigens. However, lymphocytes from such mice showed a normal reactivity against C57Bl as assessed by MLC, graft-versus-host tests, and capacity to produce specific antibodies.