title: Monocytic suppressor cells derived from peripheral blood suppress xenogenic natural killer cell lysis.
abstract: BACKGROUND
  Myeloid-derived suppressor cells (MDSCs) were initially found to contribute to immunosuppression in tumor patients and have recently been recognized as a subset of innate immune cells that are capable of regulating adaptive immunity. A variety of innate immune stimuli, such as lipopolysaccharide, act as a double-edged sword, inducing both the maturation of dendritic cells and the expansion of MDSCs.
  
  
  METHODS
  We isolated MDSCs from peripheral blood mononuclear cells (PBMCs) and examined the suppressive effect of MDSCs against xenocytotoxicity mediated by YT cells, a natural killer-like cell line, with the use of the lactate dehydrogenase assay method.
  
  
  RESULTS
  Although primed MDSCs induced no significant suppression in YT cell-mediated cytotoxicity, activated MDSCs significantly suppressed the xenogenic cytotoxicity.
  
  
  CONCLUSIONS
  These findings indicate that MDSCs have a great deal of potential as a therapeutic strategy for dealing with xenograft rejection. Further investigations of the underlying mechanisms will facilitate the development of this therapeutic strategy.
authors.affiliation: Division of Organ Transplantation, Department of Surgery, Osaka University Graduate School of Medicine, Suita, Osaka, Japan. Electronic address: amaeda@orgtrp.med.osaka-u.ac.jp.
authors.forename: A
authors.initials: A
authors.lastname: Maeda
authors.affiliation: Division of Organ Transplantation, Department of Surgery, Osaka University Graduate School of Medicine, Suita, Osaka, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kawamura
authors.affiliation: Division of Organ Transplantation, Department of Surgery, Osaka University Graduate School of Medicine, Suita, Osaka, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Nakahata
authors.affiliation: Division of Organ Transplantation, Department of Surgery, Osaka University Graduate School of Medicine, Suita, Osaka, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Ueno
authors.affiliation: Division of Organ Transplantation, Department of Surgery, Osaka University Graduate School of Medicine, Suita, Osaka, Japan.
authors.forename: N
authors.initials: N
authors.lastname: Usui
authors.affiliation: Division of Organ Transplantation, Department of Surgery, Osaka University Graduate School of Medicine, Suita, Osaka, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Eguchi
authors.affiliation: Division of Organ Transplantation, Department of Surgery, Osaka University Graduate School of Medicine, Suita, Osaka, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Miyagawa
mesh_terms: D056704:Adaptive Immunity; D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D002460:Cell Line; D018920:Coculture Techniques; D003602:Cytotoxicity, Immunologic; D042783:Endothelial Cells / Q000276:immunology*; D006801:Humans; D007113:Immunity, Innate; D007694:Killer Cells, Natural / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D007770:L-Lactate Dehydrogenase / Q000378:metabolism; D008070:Lipopolysaccharides / Q000494:pharmacology; D009000:Monocytes / Q000187:drug effects / Q000276:immunology*; D011070:Poly I-C / Q000494:pharmacology; D013552:Swine; D014183:Transplantation, Heterologous
chemical_list: D015415:Biomarkers; D008070:Lipopolysaccharides; D007770:L-Lactate Dehydrogenase; D011070:Poly I-C