Priming of multiple T cell subsets by modified-live and inactivated bovine respiratory syncytial virus vaccines.
T cell activity is a critical component of immunity to bovine respiratory syncytial virus (BRSV). We tested the effects of immunization by modified-live and inactivated BRSV vaccines on cell-mediated and humoral immunity in young calves. The two forms of vaccine stimulated similar serum neutralizing antibody production, although the early kinetics of those responses differed. CD4+, CD8+, and gammadelta T cells were analyzed before and after immunization for BRSV-specific in vitro recall responses, as evaluated by CD25 upregulation measured by flow cytometry. Modified-live virus (MLV) primed each of the three subsets for statistically significant in vitro responses to antigen. Inactivated vaccine also primed each T cell population for significant antigen-driven CD25 upregulation, including responses by CD4+ and gammadelta T cells that were stronger and longer-lasting than those primed by MLV. Monoclonal antibody was used in additional assays to block MHC class I during incubation of BRSV antigen with peripheral blood mononuclear cells from an animal in the inactivated vaccine group. The recall response by CD8+ T cells was more inhibited by this treatment than the other subsets, further suggesting that the inactivated vaccine had primed antigen-specific CD8+ T cells. In summary, the data indicate that balanced BRSV-specific T cell responses can be induced by inactivated, as well as modified-live, conventional vaccines, which may implicate an alternative pathway of MHC class I antigen presentation.
Sandbulte
Matthew R
MR
Department of Veterinary Microbiology and Preventive Medicine, College of Veterinary Medicine, 2156 Veterinary Medicine, Iowa State University, Ames, IA 50011, USA.
Roth
James A
JA
D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000276:immunology* / Q000821:virology; D005434:Flow Cytometry / Q000662:veterinary; D015395:Histocompatibility Antigens Class I / Q000276:immunology; D007114:Immunization / Q000662:veterinary; D008213:Lymphocyte Activation / Q000276:immunology; D008297:Male; D009500:Neutralization Tests / Q000662:veterinary; D018357:Respiratory Syncytial Virus Infections / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary* / Q000821:virology; D018112:Respiratory Syncytial Virus, Bovine / Q000276:immunology*; D016176:T-Lymphocyte Subsets / Q000276:immunology* / Q000821:virology; D014613:Vaccines, Attenuated / Q000276:immunology / Q000627:therapeutic use; D015164:Vaccines, Inactivated / Q000276:immunology / Q000627:therapeutic use; D014765:Viral Vaccines / Q000276:immunology* / Q000627:therapeutic use
D015395:Histocompatibility Antigens Class I; D014613:Vaccines, Attenuated; D015164:Vaccines, Inactivated; D014765:Viral Vaccines