Immunosuppressive effect of intra-lymphatic irradiation.

The effect of intra-lymphatic administration of Lipiodol-l131 on the number of T and B lymphocytes, and on the in vivo response to common antigens and to DNCB, was investigated in uremic patients in the pre-transplant period. T lymphocytes have been detected by rosette formation with sheep erythrocytes (E) and B lymphocytes by rosette formation with erythrocytes sensitized with antibody and complement (EAC). After irradiation it was observed a lymphopenia due to a statistically significant decrease in the number of both T and B peripheral blood lymphocytes and a depletion of these cells in the irradiated lymph nodes. Their ability to give delayed hypersensitivity response to common antigens in vivo was lost after intralymphatic irradiation. Two patients were able to develop sensitization to DNCB and this reaction was supressed in one of them by irradiation. These effects of intralymphatic irradiation on the immune system favours further study of this method in clinical renal transplantation.