Production of potent anti-Australia antigen sera of high specificity and sensitivity in goats

Abstract

Potent antisera of high specificity and sensitivity were produced, in goats, to purified Australia antigen (Au). The antigen was prepared by one of three methods: (i) pelleting, low pH treatment, isopycnic centrifugation two times in CsCl, and rate zonal centrifugation in sucrose; (ii) same as procedure i, with the exception of the low pH treatment; or (iii) twice banding in CsCl by using a BXIV batch-type zonal centrifuge rotor with subsequent preparative Pevikon electrophoresis. The goat anti-Au sera contained high levels of precipitating antibody as tested by immunodiffusion in agar gel and discontinuous counterimmunoelectrophoresis (DCIE) as well as specific complement-fixing antibody and could be used for routine screening of sera for Au without prior adsorption with Au-negative normal human serum (NHS). Identification of 66 of 70 positive specimens (94.3%) in a panel of 98 coded sera (49 duplicates) with 100% reproducibility was made by using one of the goat anti-Au sera at a dilution of 1:16 in the DCIE method. No false positives were recorded. Low levels of antibody against NHS components were effectively removed by a single adsorption with glutaraldehyde cross-linked NHS.