Heterotypic recognition of recombinant FMDV proteins by bovine T-cells:: the polymerase (P3Dpol) as an immunodominant T-cell immunogen

In this study we have examined the recognition of VP0, VP1, VP2, VP3 and P3D(pol) by PBMC and CD4(+) T-cells from infected, vaccinated-challenged, and multiply-vaccinated (O1, A24, C1 or ASIA1) cattle using recombinant proteins of an O1 serotype virus. The structural protein VPI was recognised in an homotypic context whereas VP2, VP3, VP4 and P3D(pol) were also recognised by T-cells from animals exposed to heterotypic viruses. Only the non-structural protein P3D(pol) was consistently recognised by T-cells from the majority of animals examined and heterotypic recognition correlated with the presence of serologically detectable P3D(pol) ii: purified virus. Thus, P3D(pol) is a major cross-reactive immunodeterminant of FMDV, eliciting heterotypic T-cell responses and, therefore, with possible potential for inclusion in a subunit vaccine. (C) 1998 Elsevier Science B.V. All rights reserved.