IIFP   25103
INSTITUTO DE ESTUDIOS INMUNOLOGICOS Y FISIOPATOLOGICOS
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Pathogenic and immunologycal study of equine herpesvirus 1 infection (EHV-1). New insights in prophylactics strategies.
Autor/es:
SCROCHI MR, BRAVI ME,FUENTEALBA NA, SGUAZZA GH, NISHIDA F, CID DE LA PAZ V, GIMENO EJ, PORTIANSKY EL, BARBEITO CG, MUGLIA CI, ZANUZZI, CN, GALOSI CG
Lugar:
Florianopolis
Reunión:
Congreso; XXV Congresso Brasileiro de Virologia, X Encontro de Virologia do Mercosul, Florianopolis Brasil, 11-14 de octubre de 2015.; 2015
Institución organizadora:
Sociedad Brasilera de Virologia
Resumen:
EHV-1 causes respiratory and nervous signs, abortionand neonatal disease. In this study we performed in vitroand in vivo (BALB/c mice) assays in order to understandthe pathogenic mechanism of the abortion, and toevaluate an immunogen capable of inducing an immuneresponse to prevent infection. In all the experiments theArgentinean AR8 strain was used. Experiment 1). Wedetermined whether EHV-1 exerts a modulatory effectof the apoptosis during its replication cycle over: a)infected, b) non-infected and c) induced to apoptosis withsorbitol heterologous (MDBK) and homologous (ED) celllines. Apoptosis was studied at different post-infection(pi) times using ethidium bromide and acridine orangestaining (fluorescent microscopy), Annexin V FITC/propidium iodide (flow cytometry-FC-) and transmissionelectron microscopy (TEM). In both infected cell lines theapoptosis was significantly lower than (c), but similarto (b); viral infection and apoptotic ultrastructuralchanges were confirmed by TEM. We conclude that EHV-1 interferes with the apoptosis of the infected cell lines,a strategy that may ensure virus replication. Experiment2). We analyzed the local immune response in the uteriand placentas of intranasally infected females by day 13of pregnancy (n=3) and the corresponding control mice(n=3). The viral isolation (VI) was carried out in lungs,uteri, placentas and fetuses taken at day 3 pi. In uteri andplacentas mRNA of TNF, IFNγ and IL10 were quantifiedby real-time RT-PCR, and the expression of their proteinswas measured by ELISA (IFNγ and IL13) or FC (TNF).The infected mice showed positive VI in their lungs, and their placentas and uteri showed a significant increaseof TNF and IFNγ mRNA and protein expression, thusindicating a strong Th1 profile. In addition, a moderateincrease of IL13 and IL10 was also found, possiblyas a homeostatic immune response to the infection.Experiment 3). We evaluated the protective effect of apurified recombinant glycoprotein (gD) combined withthe B subunit of cholera toxin (CBT) in intranasallyimmunized and challenged mice. Secretory IgAproduction was measured in upper airways lavages andplasma, and by immunohistochemistry in lungs. IgA wasdetected in the lungs of immunized mice. The use of gDand CBT prevented the arrival of the virus to the lungs.These results provide new data to better understand theabortion pathogeny of EHV-1 infection, and to validatethe new immunization strategy proposed.