title: Unrelated umbilical cord blood transplants in adults: Early recovery of neutrophils by supportive co-transplantation of a low number of highly purified peripheral blood CD34+ cells from an HLA-haploidentical donor.
abstract: OBJECTIVE, METHODS, AND RESULTS: To reduce the period of posttransplant neutropenia and related early morbidity and mortality of cord blood (CB) transplants, we assessed the feasibility of co-infusion of a low number of highly purified peripheral blood CD34+ cells from a related haploidentical donor with a CB graft. Between March 1999 and May 2002, 11 patients with high-risk hematologic malignancies were transplanted using this strategy. The seven patients who received a haploidentical peripheral blood graft and a CB graft from a sibling (6) or the father (1) had prompt recovery (9-17 days, median 10) of the absolute neutrophil count (ANC) to greater than 0.5 x 10(9)/L. Analysis of DNA polymorphisms showed initial predominance of the haploidentical genotype both in granulocytes and in mononuclear cells, and subsequent progressive replacement by cells of CB genotype until final complete CB chimerism was achieved by patients who survived for sufficient periods of time. The four patients who received maternal haploidentical cells had no significant contribution of these to blood leukocytes, although complete CB chimerism was achieved by three of them and two reached engraftment of the CB on days +20 and +36. Morbidity due to early bacterial or fungal infections was remarkably low in patients with prompt ANC recovery.
  
  
  CONCLUSIONS
  Our data show that co-infusion of a CB unit and a low number of haploidentical CD34+ cells may result in a shortened period of posttransplant neutropenia. This is likely the result of prompt and transient engraftment of the haploidentical hematopoietic stem cells that may provide the patient antimicrobial protection until the later engraftment of the CB hematopoietic stem cells.
authors.affiliation: Servicio de Hematología y Hemoterapia, Hospital Clínica Puerta de Hierro, Universidad Autónoma de Madrid, C/San Martin de Porres 4, 28035-Madrid, Spain. manueln.fernandez@uam.es
authors.forename: Manuel N
authors.initials: MN
authors.lastname: Fernández
authors.forename: Carmen
authors.initials: C
authors.lastname: Regidor
authors.forename: Rafael
authors.initials: R
authors.lastname: Cabrera
authors.forename: José A
authors.initials: JA
authors.lastname: García-Marco
authors.forename: Rafael
authors.initials: R
authors.lastname: Forés
authors.forename: Isabel
authors.initials: I
authors.lastname: Sanjuán
authors.forename: Jorge
authors.initials: J
authors.lastname: Gayoso
authors.forename: Santiago
authors.initials: S
authors.lastname: Gil
authors.forename: Elena
authors.initials: E
authors.lastname: Ruíz
authors.forename: Ann Margaret
authors.initials: AM
authors.lastname: Little
authors.forename: Alasdair
authors.initials: A
authors.lastname: McWhinnie
authors.forename: Alejandro
authors.initials: A
authors.lastname: Madrigal
mesh_terms: D000328:Adult; D018952:Antigens, CD34; D036101:Cord Blood Stem Cell Transplantation / Q000009:adverse effects / Q000379:methods* / Q000401:mortality; D005260:Female; D006085:Graft Survival; D006239:Haplotypes; D019337:Hematologic Neoplasms / Q000150:complications / Q000401:mortality / Q000628:therapy; D006650:Histocompatibility Testing; D006801:Humans; D008297:Male; D009503:Neutropenia / Q000517:prevention & control; D009504:Neutrophils / Q000166:cytology; D009894:Opportunistic Infections / Q000517:prevention & control; D036102:Peripheral Blood Stem Cell Transplantation / Q000009:adverse effects / Q000379:methods* / Q000401:mortality; D016019:Survival Analysis; D014181:Transplantation Immunology; D014184:Transplantation, Homologous / Q000276:immunology
chemical_list: D018952:Antigens, CD34