title: Repairing thymic function.
abstract: OBJECTIVE
  Maintenance of T-cell function and modulation of tolerance are critical issues in organ transplantation. The thymus is the primary organ for T-cell generation, and a preserved thymic function is essential for a self-tolerant diverse T-cell repertoire. Transplant procedures and related immunosuppressive drugs may hinder thymic integrity and function. We review here the recent advances in understanding the regulation of the unique thymic microenvironment with relevance for the field of transplantation.
  
  
  RESULTS
  Recent studies have assigned a role for IL-22 in the regeneration of thymic epithelium, and for microRNAs in the modulation of its survival and function. The interplay of key molecules in the cross-talk between thymic epithelial cells and thymocytes was depicted, opening new perspectives for the in-vitro recapitulation of T-cell development and for thymic transplantation. Additionally, the thymus was shown to be able to sustain thymocyte progenitor renewal.
  
  
  CONCLUSIONS
  These findings open new venues of research toward therapeutic interventions in the endogenous thymus to modulate or reconstitute the immune system; thymic transplantation; and the future development of artificial thymus, which would represent an important tool to achieve tolerance across the histocompatibility barriers.
authors: Unidade de Imunologia Clínica, Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.
authors: Helena
authors: H
authors: Nunes-Cabaço
authors: Ana E
authors: AE
authors: Sousa
mesh_terms: D004847:Epithelial Cells / Q000276:immunology; D006801:Humans; D007108:Immune Tolerance; D012038:Regeneration; D013601:T-Lymphocytes / Q000276:immunology*; D060168:Thymocytes / Q000276:immunology; D013950:Thymus Gland / Q000502:physiology* / Q000637:transplantation