Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 6/1/2008
Publication Date: 6/1/2008
Citation: Bannantine, J.P., Waters, W.R., Stabel, J.R., Kapur, V., Paustian, M. 2008. Use of a Mycobacterium avium subspecies paratuberculosis Protein Array for Immune Profiling of Johne's Disease Cattle [abstract]. American Society for Microbiology. p. 197.
Technical Abstract: The power of protein arrays is the ability to directly compare antibody reactivity levels of each protein against all others present on the array. The limitation of protein arrays is the ability to produced hundreds of proteins in enough quantities for analysis. In this study, over 90 recombinant proteins, each produced in Escherichia coli, were arrayed and spotted onto nitrocellulose. Included on the 96-spot array are unknown hypothetical proteins, cell surface proteins as well as proteins encoded on large sequence polymorphisms present uniquely in M. avium subsp paratuberculosis. Also included are previously reported or known M. avium subsp paratuberculosis antigens to serve as a frame of reference. The array was initially tested with sera from an M. avium subsp paratuberculosis-infected mouse to identify immunodominant antigens. Furthermore, sera from healthy control cattle (n=3) and cattle infected with either M. avium and M. bovis were exposed to the array to identify non-specific or cross-reactive epitopes. Data from these studies demonstrate a higher degree of cross reactivity with M. avium than with the more distantly related M. bovis. Sera from two experimentally infected cattle, taken pre-inoculation and at day 70, 194 and 321 post infection, identified dynamic antibody reactivity among antigens with some showing an increased response over time and others showing declining levels of reactivity over the same time period. A M. paratuberculosis specific protein, encoded by MAP0862, was strongly detected initially, but the antibody response became weaker with time. The most reactive protein was a putative surface antigen encoded by MAP1087. A second protein, MAP1204, implicated in virulence, was also strongly detected by day 70 in both cattle. Subsequent experiments showed that these two proteins were detected with sera from 5 of 9 naturally infected cattle in the subclinical stage of Johne’s disease.This powerful combination of genomic information, molecular tools, and immunological assays has enabled the identification of previously unknown antigens of M. avium subsp paratuberculosis.