Mycobacterium avium subsp.
paratuberculosis (MAP) is the etiologic agent of
paratuberculosis disease affecting ruminants worldwide. The aim of this study was to identify potential candidate
antigens and
epitopes by bio and immuno-informatic tools which could be later evaluated as
vaccines and/or diagnosis. 110
protein sequences were selected from MAP K-10 genome database: 48 classified as putative
enzymes involved in surface
polysaccharide and
lipopolysaccharide synthesis, as membrane associated and secreted
proteins, 32 as conserved
membrane proteins, and 30 as absent from other mycobacterial genomes. These 110
proteins were preliminary screened for Major Histocompatibility Complex (MHC) class II affinity and promiscuity using ProPred program. In addition, subcellular localization and host
protein homology was analyzed. From these analyses, 23 MAP
proteins were selected for a more accurate inmunoinformatic analysis (i.e. T cell and
B cell epitopes analysis) and for homology with mycobacterial
proteins. Finally, eleven MAP
proteins were identified as potential candidates for further immunogenic evaluation: six
proteins (MAP0228c, MAP1239c, MAP2232, MAP3080, MAP3131 and MAP3890) were identified as presenting potential
T cell epitopes, while 5 selected
proteins (MAP0232c, MAP1240c, MAP1738, MAP2239 and MAP3641c) harbored a large numbers of
epitopes predicted to induce both cell- and antibody-mediated immune responses. Moreover, immunogenicity of selected
epitopes from MAP1239c were evaluated in IFN-γ release assay. In summary, eleven M. avium subsp.
paratuberculosis proteins were identified by in silico analysis and need to be further evaluated for their immunodiagnostic and
vaccine potential in field and mice model.