This is a Phase II trial to determine the ability of a reduced intensity conditioning regimen to allow successful engraftment with alpha/beta T and CD19+ depleted peripheral stem cell grafts from unrelated or partially matched related donors. There are two conditioning regimens depending upon patient diagnosis and age.~The study will include patients 0-25 years with PID, including immune dysregulation syndromes for which hematopoietic stem cell transplant is indicated.~Treatment: Either conditioning regimen (listed below) followed by alpha/beta T and CD19+ depleted donor peripheral stem cells~Reduced intensity conditioning with busulfan x 8 doses, fludarabine 40 mg/m2 x 4, thiotepa 5 mg/kg x 2, anti-thymocyte globulin (ATG) 3 mg/kg x 3.~OR~Myeloablative regimen with busulfan x 16 doses or Daily for four days, fludarabine 30 mg/m2 x 5, thiotepa 5 mg/kg x 2, ATG 3 mg/kg x 2.~OR~Immunotherapy regimen on days -9, 8, 7 with anti-thymocyte globulin 3 mg/kg/day (for severe combined immunodeficiency patients only).~Infusion of alpha/beta T and CD19+ depleted donor peripheral stem cells.~Follow up, including evaluation of chimerism and immune reconstitution.
This is a Phase II trial to determine the ability of a reduced intensity conditioning regimen to allow successful engraftment with alpha/beta T and CD19+ depleted peripheral stem cell grafts from unrelated or partially matched related donors. There are two conditioning regimens depending upon patient diagnosis and age.