Linear Epitopes of PRRSV-1 Envelope Proteins Ectodomains Are Not Correlated with Broad Neutralization

Overview

Journal Porcine Health Manag

Publisher Biomed Central

Date 2024 Oct 21

PMID 39434120

Authors

Jaime Castillo-Perez

Francisco Javier Martinez-Lobo

Raquel Frometa

Jose Maria Castro

Isabel Simarro

Cinta Prieto

Affiliations

Soon will be listed here.

Abstract

Background: Neutralizing antibodies against PRRSV are capable of conferring protection against viral reinfection, but they tend to be strain specific and usually have poor cross-reactivity. Nonetheless, it has been described that there are individuals capable of efficiently neutralizing viruses of different origin, so it is expected that there are conserved neutralizing epitopes relevant for broad neutralization. However, although immunodominant regions and neutralizing epitopes have been described in different envelope proteins, their role in broad neutralization is unknown. The main objective of this study was to determine whether the linear epitopes existing in the ectodomains of PRRSV envelope proteins play a role in cross-neutralization.

Results: A pepscan analysis was carried out using synthetic peptides against the ectodomains of PRRSV envelope proteins and PRRSV-hyperimmune sera of different cross-reactivity. The results obtained confirm the existence of antigenic regions in the ectodomains of the GP2, GP3, GP4 and GP5 that tend to be relatively conserved among different PRRSV isolates. Nonetheless, these antigenic regions have poor immunogenicity since they are only recognized by a limited number of sera. Furthermore, no differences were found between the reactivity of sera with broad cross-neutralization capacity and sera with poor heterologous neutralization activity, which indicate that linear epitopes existing in the ectodomains of PRRSV envelope proteins are not relevant for the development of broadly reactive neutralizing antibodies. Subsequently, some selected peptides were used in competition assays with the virus for binding to the cell receptors and in seroneutralization inhibition assays by incubation with hyperimmune sera. Firstly, some peptides that interfere with virus infectivity were identified in competition assays, but only in the case of one viral isolate, which points to the possible existence of a strain-dependent inhibition. However, the results of the seroneutralization inhibition assay indicate that, under the conditions of our study, none of the peptides used was capable of inhibiting virus neutralization by the hyperimmune sera.

Conclusions: The results obtained indicate that the linear peptides analyzed in this study do not play a major role in the induction of broadly reactive neutralizing antibodies, which could probably depend on conformational neutralizing.

References

Havenar-Daughton C, Abbott R, Schief W, Crotty S . When designing vaccines, consider the starting material: the human B cell repertoire. Curr Opin Immunol. 2018; 53:209-216. PMC: 6148213. DOI: 10.1016/j.coi.2018.08.002. View

Brown E, Lawson S, Welbon C, Gnanandarajah J, Li J, Murtaugh M . Antibody response to porcine reproductive and respiratory syndrome virus (PRRSV) nonstructural proteins and implications for diagnostic detection and differentiation of PRRSV types I and II. Clin Vaccine Immunol. 2009; 16(5):628-35. PMC: 2681581. DOI: 10.1128/CVI.00483-08. View

Scheid J, Mouquet H, Feldhahn N, Seaman M, Velinzon K, Pietzsch J . Broad diversity of neutralizing antibodies isolated from memory B cells in HIV-infected individuals. Nature. 2009; 458(7238):636-40. DOI: 10.1038/nature07930. View

Balka G, Podgorska K, Brar M, Balint A, Cadar D, Celer V . Genetic diversity of PRRSV 1 in Central Eastern Europe in 1994-2014: origin and evolution of the virus in the region. Sci Rep. 2018; 8(1):7811. PMC: 5958080. DOI: 10.1038/s41598-018-26036-w. View

Ostrowski M, Galeota J, Jar A, Platt K, Osorio F, Lopez O . Identification of neutralizing and nonneutralizing epitopes in the porcine reproductive and respiratory syndrome virus GP5 ectodomain. J Virol. 2002; 76(9):4241-50. PMC: 155073. DOI: 10.1128/jvi.76.9.4241-4250.2002. View

Mardassi H, Mounir S, Dea S . Molecular analysis of the ORFs 3 to 7 of porcine reproductive and respiratory syndrome virus, Québec reference strain. Arch Virol. 1995; 140(8):1405-18. PMC: 7087035. DOI: 10.1007/BF01322667. View

Oleksiewicz M, Botner A, Toft P, Grubbe T, Nielsen J, Kamstrup S . Emergence of porcine reproductive and respiratory syndrome virus deletion mutants: correlation with the porcine antibody response to a hypervariable site in the ORF 3 structural glycoprotein. Virology. 2000; 267(2):135-40. DOI: 10.1006/viro.1999.0103. View

Khudyakov Y, Lopareva E, Jue D, Fang S, Spelbring J, Krawczynski K . Antigenic epitopes of the hepatitis A virus polyprotein. Virology. 1999; 260(2):260-72. DOI: 10.1006/viro.1999.9813. View

Chico V, Martinez-Lopez A, Ortega-Villaizan M, Falco A, Perez L, Coll J . Pepscan mapping of viral hemorrhagic septicemia virus glycoprotein G major lineal determinants implicated in triggering host cell antiviral responses mediated by type I interferon. J Virol. 2010; 84(14):7140-50. PMC: 2898232. DOI: 10.1128/JVI.00023-10. View

10.

Wang H, Liu R, Zhang W, Sun L, Ning Z, Ji F . Identification of epitopes on nonstructural protein 7 of porcine reproductive and respiratory syndrome virus recognized by monoclonal antibodies using phage-display technology. Virus Genes. 2017; 53(4):623-635. DOI: 10.1007/s11262-017-1472-9. View

11.

Plagemann P . The primary GP5 neutralization epitope of North American isolates of porcine reproductive and respiratory syndrome virus. Vet Immunol Immunopathol. 2004; 102(3):263-75. DOI: 10.1016/j.vetimm.2004.09.011. View

12.

Geysen H, Meloen R, Barteling S . Use of peptide synthesis to probe viral antigens for epitopes to a resolution of a single amino acid. Proc Natl Acad Sci U S A. 1984; 81(13):3998-4002. PMC: 345355. DOI: 10.1073/pnas.81.13.3998. View

13.

Shi M, Lam T, Hon C, Hui R, Faaberg K, Wennblom T . Molecular epidemiology of PRRSV: a phylogenetic perspective. Virus Res. 2010; 154(1-2):7-17. DOI: 10.1016/j.virusres.2010.08.014. View

14.

Calvert J, Slade D, Shields S, Jolie R, Mannan R, Ankenbauer R . CD163 expression confers susceptibility to porcine reproductive and respiratory syndrome viruses. J Virol. 2007; 81(14):7371-9. PMC: 1933360. DOI: 10.1128/JVI.00513-07. View

15.

Van Breedam W, Delputte P, Van Gorp H, Misinzo G, Vanderheijden N, Duan X . Porcine reproductive and respiratory syndrome virus entry into the porcine macrophage. J Gen Virol. 2010; 91(Pt 7):1659-67. DOI: 10.1099/vir.0.020503-0. View

16.

Vanhee M, Costers S, Van Breedam W, Geldhof M, Van Doorsselaere J, Nauwynck H . A variable region in GP4 of European-type porcine reproductive and respiratory syndrome virus induces neutralizing antibodies against homologous but not heterologous virus strains. Viral Immunol. 2010; 23(4):403-13. PMC: 2928701. DOI: 10.1089/vim.2010.0025. View

17.

Mercer J, Helenius A . Virus entry by macropinocytosis. Nat Cell Biol. 2009; 11(5):510-20. DOI: 10.1038/ncb0509-510. View

18.

Whitworth K, Rowland R, Ewen C, Trible B, Kerrigan M, Cino-Ozuna A . Gene-edited pigs are protected from porcine reproductive and respiratory syndrome virus. Nat Biotechnol. 2015; 34(1):20-2. DOI: 10.1038/nbt.3434. View

19.

Li J, Murtaugh M . Dissociation of porcine reproductive and respiratory syndrome virus neutralization from antibodies specific to major envelope protein surface epitopes. Virology. 2012; 433(2):367-76. DOI: 10.1016/j.virol.2012.08.026. View

20.

Simek M, Rida W, Priddy F, Pung P, Carrow E, Laufer D . Human immunodeficiency virus type 1 elite neutralizers: individuals with broad and potent neutralizing activity identified by using a high-throughput neutralization assay together with an analytical selection algorithm. J Virol. 2009; 83(14):7337-48. PMC: 2704778. DOI: 10.1128/JVI.00110-09. View