New tools in assessing immune reconstitution after hematopoietic stem cell transplantation

BACKGROUND AND OBJECTIVES: Immune functions are impaired after allogeneic stem cell transplantation for several months depending on the age of the recipient, initial pathology, degree of HLA and minor histocompatibility antigens mismatches, origin and manipulation of the graft (unmanipulated or T-cell depleted bone marrow transplantation, cord blood) and post-transplantation events (acute or chronic graft-versus-host disease, relapse and infectious complications). MATERIAL AND METHODS, RESULTS AND CONCLUSION: In addition to lymphocyte phenotyping and functional assays, new tools are now available to monitor specific aspects of the immune response in the follow-up of hematopoietic stem cell transplantation: reconstitution of T cell diversity (spectratyping or Immunoscope), thymic function (TREC or "T-cell receptor rearrangement excision DNA circles") and antigen-specific T cell responses (HLA tetramers).