Detection of antibodies cross-reactive with type C RNA tumor viral p30 protein in human sera and exudate fluids.

Human sera and human exudate fluids were surveyed for the presence of antibodies cross-reacting with a type C viral protein with a molecular weight of 30,000 (p30). Antibodies cross-reactive with type C viral p30 were concentrated by means of affinity chromatography using Sepharose beads to which disrupted Simian sarcoma virus or Rauscher murine leukemia virus p30 had been coupled. Eluates obtained from the affinity beads were tested for activity against Rauscher murine leukemia virus p30, Simian sarcoma virus p30, and endogenous feline virus RD-114 p30 by radioimmunoprecipitation. Of 57 eluates tested, 29 showed activity against type C viral p30. A number of eluates were also tested for anti-p30 activity by a visual microcytotoxicity assay. Of 11 eluates positive in the radioimmunoprecipitation assay, five were also positive in the microcytotoxicity assay.