title: Lowered susceptibility of K-562 cells treated with gamma interferon in serum-free medium to natural killer cell-mediated cytolysis.
abstract: K-562 cells grown in serum-free medium were treated with gamma interferon (IFN-gamma) and they became significantly less susceptible to natural killer (NK) cell-mediated cytolysis. To examine if this loss in susceptibility was related to induced differentiation events, the presence of various antigens was determined after induction. There was a coincident expression of class I HLA common antigen, although it is not clear if this is a direct causal relationship. The level of the constitutively expressed myelomonocytic antigen, reactive with anti-Leu-M1, was not affected by IFN-gamma induction and three normally nonexpressed monocytic antigens, defined by monoclonal antibodies, remained unexpressed. IFN-gamma did induce an enhanced expression of IL-2 receptors on K-562 cells after 2 days of treatment but, thereafter, the expression appeared to be suppressed. Electron microscopy of IFN-gamma-treated cells revealed the development of increased surface blebbing and electron-dense cytoplasmic inclusions. These ultramicroscopic changes could not be correlated with definitive differentiation events. We suggest that IFN-gamma treatment of K-562 cells induces class I HLA expression and morphological changes that may be important to differentiation events that render the cells less susceptible ot NK-mediated cytolysis.
authors.affiliation: Department of Medical Biology, University of Tennessee Medical Center, Knoxville.
authors.forename: A T
authors.initials: AT
authors.lastname: Ichiki
authors.forename: D G
authors.initials: DG
authors.lastname: Sugantharaj
authors.forename: C S
authors.initials: CS
authors.lastname: Hudson
authors.forename: D A
authors.initials: DA
authors.lastname: Gerard
authors.forename: M A
authors.initials: MA
authors.lastname: Barnhill
authors.forename: E G
authors.initials: EG
authors.lastname: Bamberger
authors.forename: C J
authors.initials: CJ
authors.lastname: Wust
authors.forename: J E
authors.initials: JE
authors.lastname: Fuhr
authors.forename: C B
authors.initials: CB
authors.lastname: Lozzio
mesh_terms: D002454:Cell Differentiation; D003602:Cytotoxicity, Immunologic; D006680:HLA Antigens / Q000096:biosynthesis; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology*; D007694:Killer Cells, Natural / Q000276:immunology*; D007938:Leukemia / Q000276:immunology / Q000473:pathology; D008854:Microscopy, Electron; D009000:Monocytes / Q000276:immunology; D014407:Tumor Cells, Cultured / Q000276:immunology* / Q000473:pathology
chemical_list: D006680:HLA Antigens; D007371:Interferon-gamma