A Western blot assay for the detection of antibodies to bovine immunodeficiency-like virus in experimentally inoculated cattle,sheep, and goats

Summary A cocultivation method was used to establish a cytocidal bovine immunodeficiency-like virus (BIV) infection in primary fetal bovine lung (FBL) cell cultures. Cultures were monitored for virus production using radial immunodiffusion and agar gel immunodiffusion. Pelleted virus and detergent (CHAPS)-solubilized infected cell lysates from BIV-infected cell cultures were compared as sources of antigen for Western blots. Pelleted virus preparations from FBL-BIV cell cultures produced the best antigen for Western blot. Sheep and goats were inoculated with BIV and serum antibody responses were monitored up to 1 year post inoculation (PI). Sera from experimentally infected cattle, sheep, and goats reacted in Western blot assay with BIV viral induced polypeptides gp 110, p 72, p 55, p 50, gp 42, p 38, p 26, p 24, p 18, p 15, and p 13. Antibodies to p 26 were detected as early as 2 weeks PI in cattle, sheep, and goats. Antibodies to gp 110 were detected by 4 to 6 weeks PI in cattle, and by 9 months PI in sheep and goats. Antibodies to BIV proteins were still evident in cattle sera 2 1/2 years PI, and in sheep and goat sera 1 year PI.