Thymic Function after Hematopoietic Stem-Cell Transplantation for the Treatment of Severe Combined Immunodeficiency

Abstract

The vestigial thymus in infants with severe combined immunodeficiency is functional and can produce enough T cells after bone marrow transplantation to provide normal immune function.

Dysregulated lymphocyte proliferation and differentiation in patients with rheumatoid arthritis

“…This discovery has been used to study T-cell reconstitution following chemotherapy for HIV, 23 ASCT for myeloma, 24 and bone marrow transplantation for severe combined immunodeficiency. 25 In each situation, peripheral blood TREC content predicted subsequent lymphocyte recovery. Furthermore, the presence of TRECs in the blood of adults suggests residual thymic function beyond adolescence.…”

Matched unrelated bone marrow transplant for T+ combined immunodeficiency

“…5 Recent studies have suggested a time-dependent loss of function following T-cell-depleted MMRD BMT, associated with progressive lymphopenia, a restricted T-cell repertoire, decreased thymic output as indicated by reduced levels of TCR excision circles and abnormal humoral immunity. 6 A substantial number of SCID patients may present with a significant number of circulating autologous T cells with variable degrees of cell-mediated function. In recent years, patients with mutations in Jak-3, Zap-70, IL-2Ra and CD3 were reported to have autologous T cells and/or residual T-cell function, commonly referred to as T þ CID.…”

Successes and risks of gene therapy in primary immunodeficiencies

“…[12][13][14] Normal natural killer cell function after BMT might also be elusive. Patel et al 18 have shown decreases in T-cell production and diversity in many patients with SCID several years after haploidentical BMT, suggesting that true stem cells might not be established from the donor. Moreover, some post-BMT patients with SCID continue to experience frequent infections, growth failure, autoimmune disorders, and chronic lung disease.…”