There is no safe and effective treatment for DiGeorge syndrome and most patients die by the age of two. Complete DiGeorge syndrome is characterized by very low T cell or very low naïve T cell numbers. In this study, typical complete DiGeorge syndrome subjects underwent human postnatal cultured thymus tissue implantation (CTTI). Thymus tissue that would otherwise be discarded was processed and then implanted into complete DiGeorge subjects in the operating room. At the time of CTTI, a skin biopsy may have been obtained to look for any preexisting T cells. After CTTI, subjects were followed by routine research immune evaluations, using blood samples obtained approximately every 2-4 weeks. At approximately 2-3 months post-CTTI subjects underwent an open biopsy of the allograft. The biopsy was done under general anesthesia in the operating room. At the time of the graft biopsy, another skin biopsy was obtained to look for clonal populations of T cells.~The protocol aims include: assessing thymopoiesis in the allograft biopsy; assessing immunoreconstitution of complete DiGeorge syndrome subjects after postnatal allogeneic cultured thymus tissue implantation; assessing minimally invasive methods of assessing thymopoiesis (flow cytometry and polymerase chain reaction (PCR); assessing pre-implant T cells which do not proliferate in response to mitogens (focusing on NK-T cells); and, assessing cultured thymus tissue implantation safety and toxicity.
The study purpose is to determine whether cultured thymus tissue implantation (CTTI) is effective in treating typical complete DiGeorge syndrome.