Respiratory syncytial virus proteins: identification by immunoprecipitation

Abstract

Respiratory syncytial virus was pulse-labeled with [35S]methionine and [35S]cysteine and cell lysates were analyzed by polyacrylamide gel electrophoresis. Five 35S-labeled viral proteins ranging in MW from 21,000-73,000 (VP73, VP44, VP35, VP28 and VP21) were easily discernable above background cellular proteins. Treatment of the infected cells with 0.15 M NaCl before labeling suppressed host cell protein synthesis and allowed clearer visualization of the 5 viral proteins by polyacrylamide gel electrophoresis. Three glycoproteins (VGP 92, VGP 50 and VGP 17) were also identified after labeling with [3H]glucosamine. Five of these polypeptides (VP51, VP44, VP35, VP28 and VGP92) were antigenically active because they could be immunoprecipitated with anti-respiratory syncytial virus antibody produced in New Zealand white rabbits, cotton rats and humans before analysis by polyacrylamide gel electrophoresis. [Human epidermoid carcinoma HEp-2 and fetal fibroblast HFF and rhesus monkey embryo kidney MA104 cells were used in these studies.].