Inhibitory effect of transplanted syngeneic thymus fragments, thymus epithelium and thymocytes on the increased contact sensitivity reaction in the adult thymectomized mouse.

Thymectomy in the adult mouse leads to an increased ability to develop contact sensitivity. The effect of different types of thymus grafts to adult thymectomized mice on contact sensitivity was studied in the present investigation. An inhibition was observed after transplantation either of uncultured thymus tissue, cultured thymus epithelium or of thymocytes. The results of the study favor the hypothesis that a continuous production of suppressor cells regulates contact sensitivity in the adult mouse.