title: Effect of IL-21 on NK cells derived from different umbilical cord blood populations.
abstract: IL-21 plays a role in the proliferation and maturation of NK cells developed from hematopoietic stem cells. In this study, we found that IL-21, in the presence of physiological concentration of hydrocortisone (HC), has a significant impact on the functions of NK cells derived from umbilical cord blood (CB) populations. We demonstrate that IL-21, in combination with Flt3-ligand, IL-15 and HC, induces high proliferative responses and, apart from enhancing NK-mediated cytotoxicity, it also induces a significant increase in lymphokine-activated killer activity of CB/CD34+-derived CD56+ cells. In addition, IL-21 induced changes in the CD56+ cell cytokine secretion profile. Thus, we observed increased levels of IL-10 and granulocyte macrophage colony-stimulating factor, whereas tumor necrosis factor-alpha levels decreased. IFN-gamma production was also modified by IL-21, depending on the presence or absence of IL-18. CB/CD34+ cells did not express the IL-21R ex vivo, but receptor expression was induced during their commitment to differentiation into CD56+ cells. Our data ascribe to IL-21 an essential role on NK cell development and function under conditions similar to the in vivo CB microenvironment.
authors.affiliation: Cancer Immunology and Immunotherapy Center, Saint Savas Hospital, 171 Alexandras Avenue, Athens 115 22, Greece. perez@ciic.gr
authors.forename: Sonia A
authors.initials: SA
authors.lastname: Perez
authors.forename: Louisa G
authors.initials: LG
authors.lastname: Mahaira
authors.forename: Panagiota A
authors.initials: PA
authors.lastname: Sotiropoulou
authors.forename: Angelos D
authors.initials: AD
authors.lastname: Gritzapis
authors.forename: Eleni G
authors.initials: EG
authors.lastname: Iliopoulou
authors.forename: Dimitrios K
authors.initials: DK
authors.lastname: Niarchos
authors.forename: Nike T
authors.initials: NT
authors.lastname: Cacoullos
authors.forename: Yannis G
authors.initials: YG
authors.lastname: Kavalakis
authors.forename: Aris I
authors.initials: AI
authors.lastname: Antsaklis
authors.forename: Nectaria N
authors.initials: NN
authors.lastname: Sotiriadou
authors.forename: Constantin N
authors.initials: CN
authors.lastname: Baxevanis
authors.forename: Michael
authors.initials: M
authors.lastname: Papamichail
mesh_terms: D000893:Anti-Inflammatory Agents / Q000276:immunology / Q000494:pharmacology; D018952:Antigens, CD34 / Q000276:immunology; D019002:CD56 Antigen / Q000276:immunology; D002454:Cell Differentiation / Q000187:drug effects / Q000276:immunology*; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D016207:Cytokines / Q000276:immunology; D005312:Fetal Blood / Q000166:cytology / Q000276:immunology*; D005786:Gene Expression Regulation / Q000187:drug effects / Q000276:immunology; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000276:immunology*; D006801:Humans; D006854:Hydrocortisone / Q000276:immunology / Q000494:pharmacology; D053738:Interleukin-21 Receptor alpha Subunit; D007378:Interleukins / Q000276:immunology* / Q000494:pharmacology; D007694:Killer Cells, Natural / Q000166:cytology / Q000276:immunology*; D008565:Membrane Proteins / Q000276:immunology; D018123:Receptors, Interleukin / Q000276:immunology; D053655:Receptors, Interleukin-21; D000098546:Interleukin-21
chemical_list: D000893:Anti-Inflammatory Agents; D018952:Antigens, CD34; D019002:CD56 Antigen; D016207:Cytokines; C508117:IL21R protein, human; D053738:Interleukin-21 Receptor alpha Subunit; D007378:Interleukins; D008565:Membrane Proteins; D018123:Receptors, Interleukin; D053655:Receptors, Interleukin-21; C084881:flt3 ligand protein; D000098546:Interleukin-21; D006854:Hydrocortisone