Hematopoietic stem-cell transplantation is the treatment of choice for severe combined immunodeficiency (SCID). Despite successful T-cell engraftment in transplanted patients, B-cell function is not always achieved; up to 58% of patients require immunoglobulin therapy after receiving haploidentical transplants. We report 2 half-sibling males with X-linked γ-chain SCID treated with different sources of stem cells. Sibling 1 was transplanted with T-cell–depleted haploidentical maternal bone marrow and sibling 2 was transplanted with 7/8 human leukocyte antigen-matched unrelated umbilical cord blood. Both patients received pretransplant conditioning and posttransplant graft-versus-host-disease prophylaxis. B-cell engraftment and function was achieved in sibling 1 but not in sibling 2. This disparate result is consistent with a review of 19 other SCID children who received cord blood transplants. B-cell function, as indicated by no need for immunoglobulin therapy, was restored in 42% of patients given haploidentical transplants and in 68% of patients given matched unrelated donor transplants compared with 80% of patients given cord blood transplants. Cord blood is an alternative source of stem cells for transplantation in children with SCID and has a higher likelihood of B-cell reconstitution.
*Department of Pediatrics, Division of Immunology, Allergy, and Rheumatology
†Division of Hematology/Oncology, University of California, Los Angeles, CA
The authors declare no conflict of interest.
Reprints: Wan-Yin Chan, MD, MS, Department of Pediatrics, Division of Immunology, Allergy, and Rheumatology, University of California, 10833 Le Conte Ave., Room 12-430 MDCC, Los Angeles, CA 90095 (e-mail: firstname.lastname@example.org).
Received October 21, 2011
Accepted February 1, 2012