Submitted to: Clinical and Diagnostic Laboratory Immunology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/1/2005
Publication Date: 6/1/2005
Citation: Waters, W.R., Palmer, M.V., Bannantine, J.P., Greenwald, R., Esfandiari, J., Andersen, P., Mcnair, J., Pollock, J.M., Lyashchenko, K. 2005. Antibody responses in reindeer (rangifer tarandus) experimentally infected with mycobacterium bovis. Clinical and Diagnostic Laboratory Immunology. 12(6):727-35. Interpretive Summary: Reindeer are routinely tested for tuberculosis by tuberculin skin testing as outlined in the USDA uniform methods and rules for the eradication of bovine tuberculosis in the United States. However, skin testing has an apparent lack of specificity as numerous reindeer are classified as reactors yet the bacterium is not isolated from tissues when the animal is killed. New tests for routine surveillance of tuberculosis in reindeer are greatly needed. In the present study, it was determined that reindeer experimentally infected with tuberculosis produce antibodies to the bacterium and that these antibodies are detectable by relatively simple laboratory methods. Since this technology is easily transferred to diagnostic laboratories, serological assays may prove practical for use in surveillance of tuberculosis infection in captive reindeer. These methods should prove useful for the tuberculosis eradication program.
Technical Abstract: Despite a very low incidence of disease, reindeer (Rangifer tarandus) are subject to tuberculosis (TB) testing requirements for interstate shipment and herd accreditation. Improved TB tests are desperately needed as many reindeer are falsely classified as reactors using current testing procedures. Sera collected sequentially from 11 Mycobacterium bovis-infected (experimentally) and 4 non-infected reindeer were evaluated by ELISA, immunoblotting, and Multi-Antigen Print Immunoassay (MAPIA) for immunoglobulin specific to M. bovis antigens. Specific immunoglobulin was detected as early as 4 weeks after challenge with M. bovis. By MAPIA, sera were tested with 12 native and recombinant antigens coated on nitrocellulose. All M. bovis infected reindeer developed responses to MPB83 and a fusion protein - ACR1:MPB83 and 9/11 had responses to MPB70. Other antigens less commonly recognized included MPB59, ESAT-6, and CFP10. Administration of purified protein derivatives for skin testing boosted serum antibody responses as detected by each of the assays. Of the non-infected reindeer, 2/4 had responses detectable immediately following skin testing that correlated with pathological findings (i.e., granulomatous lesions with non-tuberculous bacteria present). Levels of antibody responses appeared to be associated with disease progression, but not with cell-mediated immunity. These findings indicate that M. bovis infection of reindeer elicits an antibody response to multiple antigens that can be boosted by skin testing. Serological tests using carefully selected specific antigens have a potential for early detection of infected reindeer.