2026-04-19T22:32:11Zhttps://recercat.cat/oai/request

oai:recercat.cat:10459.1/720862024-12-05T22:04:46Zcom_2072_3622col_2072_479130

The Ability of Porcine Reproductive and Respiratory Syndrome Virus Isolates to Induce Broadly Reactive Neutralizing Antibodies Correlates With In Vivo Protection Martínez Lobo, Francisco Javier Díez-Fuertes, Francisco Simarro, Isabel Castro, José M. Porcine reproductive and respiratory syndrome virus Broad neutralization Neutralizing antibody Crossprotection Porcine reproductive and respiratory syndrome (PRRS) is considered one of the most relevant diseases of swine. The condition is caused by PRRS virus (PRRSV), an extremely variable virus of the Arteriviridae family. Its heterogeneity can be responsible, at least partially, of the poor cross-protection observed between PRRSV isolates. Neutralizing antibodies (NAs), known to play a role in protection, usually poorly recognize heterologous PRRSV isolates, indicating that most NAs are strain-specific. However, some pigs develop broadly reactive NAs able to recognize a wide range of heterologous isolates. The aim of this study was to determine whether PRRSV isolates that induce broadly reactive NAs as determined in vitro are able to confer a better protection in vivo. For this purpose two in vivo experiments were performed. Initially, 40 pigs were immunized with a PRRSV-1 isolate known to induce broadly reactive NAs and 24 additional pigs were used as controls. On day 70 after immunization, the pigs were divided into eight groups composed by five immunized and three control pigs and exposed to one of the eight different heterologous PRRSV isolates used for the challenge. In the second experiment, the same experimental design was followed but the pigs were immunized with a PRRSV-1 isolate, which is known to generate mostly strain-specific NAs. Virological parameters, specifically viremia and the presence of challenge virus in tonsils, were used to determine protection. In the first experiment, sterilizing immunity was obtained in three groups, prevention of viremia was observed in two additional groups, although the challenge virus was detected occasionally in the tonsils of immunized pigs, and partial protection, understood as a reduction in the frequency of viremia compared with controls, was recorded in the remaining three groups. On the contrary, only partial protection was observed in all groups in the second experiment. The results obtained in this study confirm that PRRSV-1 isolates differ in their ability to induce cross-reactive NAs and, although other components of the immune response might have contributed to protection, pigs with cross-reactive NAs at the time of challenge exhibited better protection, indicating that broadly reactive NAs might play a role in protection against heterologous reinfections. This study was supported by grants AGL2007-66695, AGL2008- 05708-C02 and CSD-2006-00007 from the Spanish Government and FEI 20/39 from the University Complutense of Madrid. FM-L and F-DF were funded by Project Consolider-Ingenio 2010 CDS2006-00007 2024-12-05T22:04:46Z 2024-12-05T22:04:46Z 2024-12-05T22:04:46Z 2021-10-18T10:09:59Z 2021-10-18T10:09:59Z 2021-07 info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion http://hdl.handle.net/10459.1/72086 info:eu-repo/grantAgreement/MEC//AGL2007-66695/ES/CARACTERIZACION DE LA VARAIBILIDAD ANTIGENICA DE CEPAS DEL VIRUS DEL SINDROME REPRODUCTOR Y RESPIRATORIO PORCINO: IMPLICACIONES EN LA PROTECCION/ info:eu-repo/grantAgreement/MICINN//AGL2008-05708-C02-01/ES/CARACTERIZACION ANTIGENICA DE CEPAS DEL VIRUS DEL SINDROME REPRODUCTOR Y RESPIRATORIO PORCINO DE DISTINTO ORIGEN Y SU RELEVANCIA PARA EL DESARROLLO VACUNAS EFICACES/ info:eu-repo/grantAgreement/MICINN//AGL2008-05708-C02-02/ES/CARACTERIZACION ANTIGENICA DE CEPAS DEL VIRUS DEL SINDROME REPRODUCTOR Y RESPIRATORIO PORCINO DE DISTINTO ORIGEN Y SU RELEVANCIA PARA EL DESARROLLO DE VACUNAS EFICACES/ Reproducció del document publicat a https://doi.org/10.3389/fimmu.2021.691145 Frontiers in Immunology, 2021, vol. 12, Article 691145 cc-by (c) Martínez Lobo et al., 2021 info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/4.0/ Frontiers Media