MYCOBACTERIAL ANTIGEN-SPECIFIC ANTIBODY-RESPONSES IN BOVINE TUBERCULOSIS - AN ELISA WITH POTENTIAL TO CONFIRM DISEASE STATUS

Serological assays may help to identify animals in advanced stages of bovine tuberculosis, but most of the tests available have suboptimal s ensitivities and specificities, This study was designed to determine w hether the antibody responses to defined antigens (rMPB70, rMPB64 and rMPB59) of Mycobacterium bovis at the immunoglobulin subclass level co uld be used to develop improved serological tests, In experimentally i nfected cattle it was found that the predominant serum antibody respon se was to rMPB70, and that an IgG(1) response to this antigen was boos ted strongly by skin testing, Studies in naturally infected cattle sug gested that this memory IgG(1) anti-rMPB70 response map be able to dif ferentiate between skin test-reactor animals with and without lesions by comparing the ratio of the antibody response before and after skin testing, The study has provided a clearer understanding of the kinetic s of antibody responses to defined mycobacterial antigens at the subcl ass level in bovine tuberculosis and has made it possible to develop a novel ELISA system which may be useful in disease diagnosis.