T-cell reconstitution by thymus transplantation and transfer factor in severe combined immunodeficiency.

Reconstitution of cell-mediated immunity was achieved in a 5-month old female infant with severe combined immunodeficiency by fetal thymus transplant given simultaneously with two units of transfer factor. Thymus was obtained from a 15-week gestational age male fetus, and the two units of transfer factor from the lymphocytes of 500 ml of peripheral blood. Three weeks after transplantation, two nel HL-A antigens were detected on the infant's lymphocytes, one of which was present in the mother of the thymus donor; at the same time, some of the infant's own HL-A antigens disappeared. Thereafter, the percent of rosette-forming cells (T-cells) increased and the in vitro response to phytohemagglutinin and allogeneic lymphocytes became normal, and delayed skin tests became positive. Karyotyping of peripheral blood lymphocytes posttransplantation reveals an XY (male) pattern. These results suggest lymphocyte re-population as a result of the thymus-transfer factor therapy. Five months after transplantation, the patient has normal cellular immunity but persistent hypogammaglobulinemia. She is free of infection and growing normally on gammaglobulin injections.