title: Characterization of cord blood natural killer cells: implications for transplantation and neonatal infections.
abstract: The role of natural killer (NK) cells in hematopoietic stem cell transplantation and in the control of neonatal infections is not yet clear. Donor-versus-recipient NK cell alloreactivity was found to improve outcome in some settings of hematopoietic stem cell transplantation. We hypothesized that the role of NK cells in cord blood (CB) transplantation and neonatal infections may depend on CB NK cell maturation stage. We therefore analyzed the expression of NK cell differentiation/phenotypic markers in human CB, as well as functional properties of purified CB NK cells. CD8 and CD57 expression was lower in CB than in adult NK cells. However, the expression of other differentiation markers was similar, as was cell surface density of CD56, the percentage of late NK cell precursors, interferon-gamma production, and the proliferative response of purified NK cells to IL-2. Spontaneous cytotoxic activity of purified CB NK cells against NK-sensitive targets was low but reached adult levels after treatment with IL-15. Expression of perforin and granzyme B was higher in CB NK cells (90 versus 58% and 86 versus 69%, respectively). intercellular adhesion molecule-1 and CD161 expression was lower in CB. Surprising, fewer CB NK cells expressed L-selectin, a marker of immature NK cells. Taken together, our results suggest that CB NK cells are phenotypically and functionally mature.
authors.affiliation: Laboratory of Immunovirology, Hôpital Sainte-Justine, Montreal, Quebec, Canada, H3T 1C5.
authors.forename: Jean-Hugues
authors.initials: JH
authors.lastname: Dalle
authors.forename: José
authors.initials: J
authors.lastname: Menezes
authors.forename: Eric
authors.initials: E
authors.lastname: Wagner
authors.forename: Marie
authors.initials: M
authors.lastname: Blagdon
authors.forename: Josette
authors.initials: J
authors.lastname: Champagne
authors.forename: Martin A
authors.initials: MA
authors.lastname: Champagne
authors.forename: Michel
authors.initials: M
authors.lastname: Duval
mesh_terms: D019002:CD56 Antigen / Q000096:biosynthesis; D018959:CD57 Antigens / Q000096:biosynthesis; D016827:CD8 Antigens / Q000096:biosynthesis; D049109:Cell Proliferation; D017690:Cell Transplantation / Q000379:methods*; D016207:Cytokines / Q000378:metabolism; D005312:Fetal Blood / Q000166:cytology*; D005434:Flow Cytometry; D053804:Granzymes; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism; D019409:Interleukin-15 / Q000378:metabolism; D007376:Interleukin-2 / Q000378:metabolism; D007694:Killer Cells, Natural / Q000166:cytology*; D019041:L-Selectin / Q000096:biosynthesis; D007963:Leukocytes, Mononuclear / Q000166:cytology; D008562:Membrane Glycoproteins / Q000096:biosynthesis; D054353:Perforin; D010641:Phenotype; D052899:Pore Forming Cytotoxic Proteins; D015375:Receptors, Interleukin-2 / Q000378:metabolism; D012697:Serine Endopeptidases / Q000096:biosynthesis
chemical_list: D019002:CD56 Antigen; D018959:CD57 Antigens; D016827:CD8 Antigens; D016207:Cytokines; D019409:Interleukin-15; D007376:Interleukin-2; D008562:Membrane Glycoproteins; D052899:Pore Forming Cytotoxic Proteins; D015375:Receptors, Interleukin-2; D054353:Perforin; D019041:L-Selectin; D007371:Interferon-gamma; C509213:GZMB protein, human; D053804:Granzymes; D012697:Serine Endopeptidases