|CAMPO, JOSEPH - Antigen Discovery, Inc|
|LI, LINGLING - Pennsylvania State University|
|RANDALL, ARLO - Antigen Discovery, Inc|
|PABLO, JOZELYN - Antigen Discovery, Inc|
|PRAUL, CRAIG - Pennsylvania State University|
|GROHN, YRJO - Cornell University - New York|
|KAPUR, VIVEK - Pennsylvania State University|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 10/5/2015
Publication Date: 12/4/2015
Citation: Bannantine, J.P., Campo, J., Li, L., Randall, A., Pablo, J., Praul, C., Stabel, J.R., Grohn, Y., Kapur, V. 2015. Application of a Mycobacterium tuberculosis protein array for antigen discovery in Johne's disease. Meeting Abstract. CRWAD-NIFA Project Directors meeting.
Technical Abstract: Mycobacterium avium subspecies paratuberculosis (Map), the bacterium that causes Johne’s disease, is a major health concern in farmed ruminant livestock including sheep and cattle. Diagnosis of Map infections, particularly of subclinical animals remains challenging, and we lack effective vaccines for preventing the spread of the disease which is now endemic in much of the world. Previous studies have explored the application of protein arrays consisting of recombinant proteins and have shown these to be promising tools for antigen discovery, however these arrays contained less than 20% of the predicted proteome. Given the close phylogenetic relationship between Map and the human pathogen, Mycobacterium tuberculosis (Mtb), we here investigated the potential utility of an Mtb whole genome protein arrays for identification of Map sero-reactive antigens. A genome-scale comparative pairwise analysis of amino acid identity between orthologous proteins in Map and Mtb showed an average of 62% identity (range 19% to 100%) amongst the protein encoding genes in Map, with more than half of the orthologous proteins sharing > 75% identity. Analysis of the Mtb protein array probed with sera from cattle with Johne’s disease showed antibody binding to Mtb proteins with high identity to Map orthologs, and suggest that an estimated additional 1,800 candidate proteins may likely be screened for sero-reactivity, and several strong novel Map antigens, including MAP0654, MAP0856c, MAP2942c and MAP4264 were identified from both protein arrays. The results of our investigations suggest that the application of the Mtb protein array is likely to greatly expand the number of testable Map proteins for antigen discovery.