RT Journal Article T1 Hematopoietic stem cell transplantation for CD3δ deficiency A1 Marcus, Nufar A1 Gil Herrera, Juana A1 Regueiro González-Barros, José Ramón A1 Roifman, Chaim M. AB BackgroundCD3δ deficiency is a fatal form of severe combined immunodeficiency that can be cured by hematopoietic stem cell transplantation (HSCT). The presence of a thymus loaded with T-cell progenitors in patients with CD3δ deficiency may require special considerations in choosing the regimen of conditioning and the type of HSCT.ObjectivesTo study the outcome of CD3δ deficiency by using various modalities of stem cell transplantation.MethodsWe analyzed data on 13 patients with CD3δ deficiency who underwent HSCT in 7 centers. HSCT was performed by using different sources of donor stem cells as well as various conditioning regimens.ResultsOne patient received stem cells from a matched related donor and survived after a second transplant, needing substantial conditioning in order to engraft. Only 2 of 7 other patients who received a mismatched related donor transplant survived; 2 of them had no conditioning, whereas the others received various combinations of conditioning regimens. Engraftment of T cells in the survivors appears incomplete. Three other patients who received stem cells from a matched unrelated donor survived and enjoyed full immune reconstitution. Two patients received unrelated cord blood without conditioning. One of them has had a partial but stable engraftment, whereas the other engrafted well but is only 12 months after HSCT. We also report here for the first time that patients with CD3δ deficiency can present with typical features of Omenn syndrome.ConclusionsHSCT is a successful treatment for patients with CD3δ deficiency. The small number of patients in this report prevents definitive statements on the importance of survival factors, but several are suggested: (1) HLA-matched donor transplants are associated with superior reconstitution and survival than are mismatched donor transplants; (2) substantial conditioning appears necessary; and (3) early diagnosis and absence of opportunistic infections may affect outcome. PB Elsevier SN 0091-6749 YR 2011 FD 2011-11 LK https://hdl.handle.net/20.500.14352/107448 UL https://hdl.handle.net/20.500.14352/107448 LA eng NO Marcus N, Takada H, Law J, Cowan MJ, Gil J, Regueiro JR, Plaza Lopez de Sabando D, Lopez-Granados E, Dalal J, Friedrich W, Manfred H, Hanson IC, Grunebaum E, Shearer WT, Roifman CM. Hematopoietic stem cell transplantation for CD3δ deficiency. J Allergy Clin Immunol. 2011 Nov;128(5):1050-7. doi: 10.1016/j.jaci.2011.05.031. Epub 2011 Jul 16. Erratum in: J Allergy Clin Immunol. 2013 Nov;132(5):1259 DS Docta Complutense RD 7 abr 2025