RESUMO
The innate and acquired immune response induced by a commercial inactivated vaccine against Bovine Herpesvirus-1 (BoHV-1) and protection conferred against the virus were analyzed in cattle. Vaccination induced high levels of BoHV-1 antibodies at 30, 60, and 90 days post-vaccination (dpv). IgG1 and IgG2 isotypes were detected at 90 dpv, as well as virus-neutralizing antibodies. An increase of anti-BoHV-1 IgG1 in nasal swabs was detected 6 days post-challenge in vaccinated animals. After viral challenge, lower virus excretion and lower clinical score were observed in vaccinated as compared to unvaccinated animals, as well as BoHV-1-specific proliferation of lymphocytes and production of IFNγ, TNFα, and IL-4. Downregulation of the expression of endosome Toll-like receptors 8-9 was detected after booster vaccination. This is the first thorough study of the immunity generated by a commercial vaccine against BoHV-1 in cattle.
Assuntos
Anticorpos Neutralizantes/biossíntese , Herpesvirus Bovino 1/imunologia , Vacinas contra Herpesvirus/administração & dosagem , Imunoglobulina G/biossíntese , Rinotraqueíte Infecciosa Bovina/prevenção & controle , Receptor 8 Toll-Like/imunologia , Receptor Toll-Like 9/imunologia , Imunidade Adaptativa/efeitos dos fármacos , Animais , Anticorpos Antivirais , Bovinos , Proliferação de Células , Endossomos/imunologia , Endossomos/metabolismo , Expressão Gênica , Herpesvirus Bovino 1/patogenicidade , Imunidade Inata/efeitos dos fármacos , Imunização Secundária/métodos , Rinotraqueíte Infecciosa Bovina/genética , Rinotraqueíte Infecciosa Bovina/imunologia , Rinotraqueíte Infecciosa Bovina/virologia , Interferon gama/genética , Interferon gama/imunologia , Interleucina-4/genética , Interleucina-4/imunologia , Linfócitos/imunologia , Linfócitos/virologia , Masculino , Cavidade Nasal/imunologia , Cavidade Nasal/virologia , Receptor 8 Toll-Like/agonistas , Receptor 8 Toll-Like/genética , Receptor Toll-Like 9/agonistas , Receptor Toll-Like 9/genética , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Vacinação/métodos , Vacinas de Produtos InativadosRESUMO
DNA vaccines are capable of inducing humoral and cellular immunity, and are important to control bovine herpesvirus 1 (BoHV-1), an agent of the bovine respiratory disease complex. In previous work, a DNA plasmid that encodes a secreted form of BoHV-1 glycoprotein D (pCIgD) together with commercial adjuvants provided partial protection against viral challenge of bovines. In this work, we evaluate new molecules that could potentiate the DNA vaccine. We show that a plasmid encoding a soluble CD40 ligand (CD40L) and the adjuvant Montanide™ GEL01 (GEL01) activate in vitro bovine afferent lymph dendritic cells (ALDCs). CD40L is a co-stimulating molecule, expressed transiently on activated CD4+ T cells and, to a lesser extent, on activated B cells and platelets. The interaction with its receptor, CD40, exerts effects on the presenting cells, triggering responses in the immune system. GEL01 was designed to improve transfection of DNA vaccines. We vaccinated cattle with: pCIgD; pCIgD-GEL01; pCIgD with GEL01 and CD40L plasmid (named pCIgD-CD40L-GEL01) or with pCIneo vaccines. The results show that CD40L plasmid with GEL01 improved the pCIgD DNA vaccine, increasing anti-BoHV-1 total IgGs, IgG1, IgG2 subclasses, and neutralizing antibodies in serum. After viral challenge, bovines vaccinated with pCIgD-GEL01-CD40L showed a significant decrease in viral excretion and clinical score. On the other hand, 80% of animals in group pCIgD-GEL01-CD40L presented specific anti-BoHV-1 IgG1 antibodies in nasal swabs. In addition, PBMCs from pCIgD-CD40L-GEL01 had the highest percentage of animals with a positive lymphoproliferative response against the virus and significant differences in the secretion of IFNγ and IL-4 by mononuclear cells, indicating the stimulation of the cellular immune response. Overall, the results demonstrate that a plasmid expressing CD40L associated with the adjuvant GEL01 improves the efficacy of a DNA vaccine against BoHV-1.
