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

Abstract

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.

Effect of bovine immunodeficiency-like virus infection on immune function in experimentally infected cattle

“…Western blot analysis and virus isolations by cocultivation with FBL cells were performed as previously reported (Whetstone et al, 1990(Whetstone et al, , 1991. The ELISA titers reported for BIV are from an ELISA that detects antibody to the whole virus (Whetstone, 1992).…”

“…The control and inoculated calves were housed in separate rooms inside isolation facilities at the Veterinary Medical Research Institute, Ames, lA. All of the animals were tested on Days -24 and 60 for antibodies to bovine syncytial virus ( BSV), and bovine leukemia virus (BLV) by agar gel immunodiffusion (Malmquist et al, 1969;Miller and Vander Maaten 1976 ), and to BIV by Western blot analysis (Whetstone et al, 1991). Two animals appeared to have maternal antibodies to BLV or BSV.…”

“…The ELISA titers reported for BIV are from an ELISA that detects antibody to the whole virus (Whetstone, 1992). The virus is grown as previously described (Whetstone et al, 1991 ) . Plates are coated with antigen (virus) in carbonate buffer, pH 9.6, and blocked with 0.1% bovine serum albumin +0.2% Tween 20.…”

The antibody response of cattle infected with bovine immunodeficiency virus to peptides of the viral transmembrane protein.

“…Our finding, that antibodies to BIV TM peptides persist at a high level for 50 weeks in the sera of cattle experimentally infected with BIV FL""# , has consequences for the identification of cattle infected with BIV, since previous studies indicate that antibodies to some of the structural proteins of the virus may decline to undetectable levels within a few months of infection (Isaacson et al, 1995). Antibodies to p26, the major BIV capsid protein, were found to persist for more than 2 years after inoculation of experimentally infected cattle (Whetstone et al, 1990(Whetstone et al, , 1991. While anti-p26 antibodies were detected 2 weeks after infection and peaked at 6-8 weeks, two out of four of the cattle tested had no detectable antibody by 19-38 months post-infection, as determined by Western blot and IFA (Whetstone et al, 1990).…”

Detection of Bovine Immunodeficiency Virus Antibodies in Cattle by Western Blot Assay with RecombinantGagProtein

“…23 To screen for the naturally infected cattle, different serological approaches have been employed, such as e.g, immunofluorescence assays (IFAs), western blot assay, and enzyme-linked immunosorbant assay (ELI-SA). 23,26,27 Although these tests can detect BIV exposure, they may lack specificity or require a large amount of native viral antigen. Because BIV can be propagated well only in primary bovine cell cultures, the use of native viral proteins for serological testing is quite difficult.…”