Characterization of a series of monoclonal antibodies specific for bovine adenovirus serotype BAV3 hexon antigen and their use in an ELISA for detection of adenoviral hexons.

After immunization of mice with purified hexon (the main capsid antigen) of bovine adenovirus serotype BAV3 we have obtained a set of 16 individual hybridoma clones producing MAb's against BAV3 hexon. All MAb's were shown to belong to immunoglobulin G class. Specificity of the most avid MAb marked B3Hx-1 was tested on a panel of representative hexon antigens from 16 adenovirus serotypes of human and animal origin using several immunoassays. In Western blot analysis the MAb B3Hx-1 reacted only with native (trimeric) form of hexon protein and not with denaturated hexon polypeptide chains. The epitope defined by B3Hx-1 appeared stable against SDS at ambient temperature and against chloramine-promoted iodination. The specificity of the epitope was characterized as almost genus-crossreactive: it was absent from hexons of avian and of bovine subgroup 2 adenovirus serotypes and present in most hexons of bovine, canine, simian and human adenoviruses tested. Within the latter group its expression was weak or absent only for human subgenus C serotypes. Several variants of sandwich-type ELISA were developed using MAb B3Hx-1 and different polyclonal antibodies against hexons of mammalian adenoviruses. The level of hexon detection for different adenovirus serotypes varied in range 10(-9) to 10(-8) g per ml.