title: Impact of HLA in cord blood transplantation outcomes.
abstract: Umbilical cord blood (UCB) emerged in the last 20 years as a valid alternative source of hematopoietic stem cell (HSC) in allogeneic transplantation setting, mainly in the absence of a fully human leucocyte antigen (HLA)-matched sibling. The probability of finding a matched unrelated donor through the registries varies from 20 to 70%, depending on the ethnicity of the patients. Therefore, patients in need may benefit of an HLA-mismatched hematopoietic stem cell transplantation from haploidentical donors or from UCB. One of the advantages of using UCB is the lower incidence of acute graft-versus-host-disease and allowance of greater HLA mismatch. Conversely, the low number of HSCs and lymphocytes and specific immunological features of T cells are associated with delayed engraftment and immune reconstitution and consequently, increased opportunistic infections. Nevertheless, retrospective studies showed similar results comparing UCB with other stem cell sources, both in pediatric and adult setting. The ability to use partially HLA-matched UCB units allows expanding the donor pool. Many UCB banks have strategies to increase their inventory including UCB grafts that have rare haplotypes. HLA and cell dose are very important factors associated with outcomes after umbilical cord blood transplantation (UCBT) that interact with each other. Increasing cell dose counterbalances the number of HLA disparities. Understanding those interactions, the role of HLA mismatches and other immunogenic factors, are important to allow clinicians to choose the best cord blood graft for patients. This review will describe the role of HLA in UCBT setting.
authors.affiliation: Service d'Hématologie et Thérapie Cellulaire, Hôpital Saint Antoine, Paris, France.|Eurocord, Hôpital Saint Louis AP-HP, University Paris VII IUH, Paris, France.|Monacord, Centre Scientifique de Monaco, Monaco, Principauté de Monaco.
authors.forename: A
authors.initials: A
authors.lastname: Ruggeri
authors.affiliation: Eurocord, Hôpital Saint Louis AP-HP, University Paris VII IUH, Paris, France.|Monacord, Centre Scientifique de Monaco, Monaco, Principauté de Monaco.
authors.forename: A
authors.initials: A
authors.lastname: Paviglianiti
authors.affiliation: Eurocord, Hôpital Saint Louis AP-HP, University Paris VII IUH, Paris, France.|Monacord, Centre Scientifique de Monaco, Monaco, Principauté de Monaco.
authors.forename: E
authors.initials: E
authors.lastname: Gluckman
authors.affiliation: Eurocord, Hôpital Saint Louis AP-HP, University Paris VII IUH, Paris, France.|Department of Haematology, Oxford University Hospitals NHS Trust, Churchill Hospital, Oxford, UK.|NHS Blood and Transplant, Oxford Centre, John Radcliffe Hospital, Oxford, UK.
authors.forename: V
authors.initials: V
authors.lastname: Rocha
mesh_terms: D000208:Acute Disease; D000328:Adult; D002452:Cell Count; D002648:Child; D036101:Cord Blood Stem Cell Transplantation; D006086:Graft vs Host Disease / Q000235:genetics / Q000276:immunology / Q000473:pathology / Q000517:prevention & control; D006680:HLA Antigens / Q000235:genetics / Q000276:immunology*; D006239:Haplotypes; D019337:Hematologic Neoplasms / Q000235:genetics / Q000276:immunology / Q000473:pathology / Q000628:therapy*; D018380:Hematopoietic Stem Cell Transplantation; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000276:immunology*; D006650:Histocompatibility Testing; D006801:Humans; D009894:Opportunistic Infections / Q000276:immunology / Q000382:microbiology / Q000517:prevention & control; D016896:Treatment Outcome; D061349:Unrelated Donors
chemical_list: D006680:HLA Antigens
keywords: cord blood transplantation; human leucocyte antigen; leukemia; total nucleated cell