Immunosuppressive Effect of the Depletion of Circulating Lymphocytes by Chronic Irradiation of the Rat Spleen

The effect of chronic irradiation of the spleen with a ³²P polyethylene strip applied to the lateral surface of the spleen on the blood level of circulating small lymphocytes and on the immune response to 2,4-dinitrophenyl-bovine γ globulin administered in complete Freund's adjuvant was investigated in the rat. Irradiation restricted to the spleen caused severe lymphopenia and significantly depressed the cellular and humoral immune response to this antigen.