Enzyme-linked protein A: an enzyme-linked immunosorbent assay reagent for detecting antibodies in tuberculous exotic animals.

An enzyme-linked immunosorbent assay (ELISA) was developed, using protein A labeled with horseradish peroxidase for detecting antibodies in tuberculous exotic mammals (llamas, rhinoceroses, elephants). The modified ELISA provides a rapid procedure for screening several animal species simultaneously for tuberculosis without the production of specific anti-species conjugates. Heat-killed cells of Mycobacterium bovis and M avium and purifed protein-derivative tuberculin of M bovis were used as antigens for ELISA.