Abstract
Transplantation of two fetal thymuses failed to reconstitute the immune function in a patient with the DiGeorge syndrome. Serum thymic hormones (facteur thymique serique and thymopoietin), which had been nondetectable, became normal after thymus transplantation. Studies done on the patient's fractionated bone marrow cells
in vitro appeared to reflect defective capacity for T-lymphocyte differentiation. In spite of the efforts at treatment, the child died at 2 years of age, apparently due to an associated cardiovascular abnormality. At autopsy, no thymic tissue could be found. Failure of immunologic reconstitution after fetal thymus transplantation in this patient with the DiGeorge syndrome may have resulted from deficiencies of precursor cells.
