Suppressor cells in the graft vs host reaction

It is shown that a population of cells exists in the spleen of 6 week old NZB/W mice, capable of suppressing the GVH reactivity of 25 week old spleen cells. Thymus cells of 6 week old NZB/W mice also suppressed the GVH response. Two T cells (effector and amplifier) have previously been shown to cooperate in the GVH reaction. Although a number of interpretations may be offered, one possibility is that a third type of T cell, a suppressor cell, may also be involved in the regulation of this cell mediated immune reaction.