title: Interferon-gamma can remain on the cell surface during the induction of the antiviral state.
abstract: The antiviral activity of cell-associated, non-elutable recombinant human gamma interferon (rHuIFN-gamma) was neutralized by antibody. The neutralization of cell-associated rHuIFN-gamma was maximal through 2 h (60-100%) and declined through 8 h (20-40%). Concomitantly, the antiviral activity of cell-associated [Met-Gln-Asp-Pro]-rHuIFN-gamma was sensitive to trypsin digestion over the same time period. However, the cell-associated antiviral activity of [Cys-Tyr-Cys]-rHuIFN-gamma remained sensitive to trypsin through 8 h. Neutralization of cell-associated rHuIFN-gamma by antibodies to the N-terminal end of HuIFN-gamma suggests that the N-terminal end(s) of cell-associated rHuIFN-gamma is directed outward from the receptor. Further, immunoprecipitation of radio-labelled rHuIFN-gamma by antibody alone suggests that biologically active rHuIFN-gamma is an oligomer. Taken together, these studies suggest that neutralization of cell-associated rHuIFN-gamma is probably due to divalent binding of antibody to or between rHuIFN-gamma in receptors on the cell surface. Also, our studies indicate that rHuIFN-gamma can remain associated with the cell surface during the induction of the antiviral state (AVS) and that binding of antibody to cell-associated rHuIFN-gamma inhibits the molecular events responsible for induction of the AVS.
authors.affiliation: Department of Microbiology, Louisiana State University Medical Center, Shreveport 71130.
authors.forename: M P
authors.initials: MP
authors.lastname: Langford
authors.forename: W G
authors.initials: WG
authors.lastname: Gates
authors.forename: R
authors.initials: R
authors.lastname: Kaiwar
mesh_terms: D000327:Adsorption; D000595:Amino Acid Sequence; D000818:Animals; D000954:Antigens, Surface / Q000276:immunology; D002462:Cell Membrane / Q000276:immunology; D002478:Cells, Cultured; D000939:Epitopes / Q000276:immunology; D006801:Humans; D007371:Interferon-gamma / Q000276:immunology*; D007739:L Cells; D051379:Mice; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000276:immunology; D011994:Recombinant Proteins; D014357:Trypsin; D014721:Vesicular stomatitis Indiana virus / Q000276:immunology*
chemical_list: D000954:Antigens, Surface; D000939:Epitopes; D010446:Peptide Fragments; D011994:Recombinant Proteins; D007371:Interferon-gamma; D014357:Trypsin