title: Umbilical cord blood CD34(+)cell-derived progeny produces human leukocyte antigen-G molecules with immuno-modulatory functions.
abstract: Human umbilical cord blood units (UCBs) are an alternative source in allogeneic-stem-cell transplantation. Human leukocyte antigen (HLA)-G is a tolerogenic molecule with a possible implication in UCB immunoregulatory effect. HLA-G expression was observed in UCB myeloid and plasmacytoid dendritic cells; in contrast, CD34(+) cells did not produce this molecule. CD34(+) cells are primitive hematopoietic progenitor cells that are present in UCB and are necessary for long-term engraftment via production of immunoregulatory molecules and a hematopoietic progeny that supports cellular recovery. The role of these cells in UCB transplantation needs further evaluation of HLA-G expression in CD34(+) cells and their hematopoietic progeny. We confirmed the absence of HLA-G expression in CD34(+) cells, whereas CD34(+)-derived progeny secreted HLA-G molecules and expressed HLA-G mRNA in in vitro cultures. Furthermore, soluble HLA (sHLA)-G molecules purified from the culture supernatants of CD34(+)-derived progeny were able to suppress lymphoproliferative response in an HLA-G dose-dependent manner. Overall these results identify CD34(+)-derived hematopoietic progeny as producers of HLA-G molecules and support a role of this antigen as an immuno-modulatory factor in UCB.
authors.affiliation: Immunohaematology and Transfusion Medicine Service, S.Orsola-Malpighi Hospital, University of Bologna, Bologna, Italy.
authors.forename: Marina
authors.initials: M
authors.lastname: Buzzi
authors.forename: Francesco
authors.initials: F
authors.lastname: Alviano
authors.forename: Diana
authors.initials: D
authors.lastname: Campioni
authors.forename: Marina
authors.initials: M
authors.lastname: Stignani
authors.forename: Loredana
authors.initials: L
authors.lastname: Melchiorri
authors.forename: Antonella
authors.initials: A
authors.lastname: Rotola
authors.forename: Pierluigi
authors.initials: P
authors.lastname: Tazzari
authors.forename: Francesca
authors.initials: F
authors.lastname: Ricci
authors.forename: Cristiana
authors.initials: C
authors.lastname: Vaselli
authors.forename: Adriana
authors.initials: A
authors.lastname: Terzi
authors.forename: Pasquale P
authors.initials: PP
authors.lastname: Pagliaro
authors.forename: Antonio
authors.initials: A
authors.lastname: Cuneo
authors.forename: Francesco
authors.initials: F
authors.lastname: Lanza
authors.forename: Andrea
authors.initials: A
authors.lastname: Bontadini
authors.forename: Olavio R
authors.initials: OR
authors.lastname: Baricordi
authors.forename: Roberta
authors.initials: R
authors.lastname: Rizzo
mesh_terms: D000328:Adult; D018952:Antigens, CD34 / Q000276:immunology*; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005312:Fetal Blood / Q000166:cytology* / Q000276:immunology*; D005786:Gene Expression Regulation; D059951:HLA-G Antigens / Q000276:immunology* / Q000302:isolation & purification / Q000494:pharmacology; D006801:Humans; D007155:Immunologic Factors / Q000494:pharmacology; D011247:Pregnancy
chemical_list: D018952:Antigens, CD34; D059951:HLA-G Antigens; D007155:Immunologic Factors