PMID- 32796065 OWN - NLM STAT- MEDLINE DCOM- 20201230 LR - 20210414 IS - 1098-5514 (Electronic) IS - 0022-538X (Print) IS - 0022-538X (Linking) VI - 94 IP - 21 DP - 2020 Oct 14 TI - Porcine Reproductive and Respiratory Syndrome Virus Promotes SLA-DR-Mediated Antigen Presentation of Nonstructural Proteins To Evoke a Nonneutralizing Antibody Response In Vivo. LID - 10.1128/JVI.01423-20 [doi] LID - e01423-20 AB - The humoral immune response against porcine reproductive and respiratory syndrome virus (PRRSV) infection is characterized by a rapid induction of nonneutralizing antibodies (non-NAbs) against nonstructural proteins (NSPs). Here, we systematically investigated the potential mechanism for the induction of PRRSV NSP-specific non-NAbs. Our data suggested that PRRSV NSP-specific antibodies appeared within 10 days after PRRSV infection in vivo In the in vitro model, functional upregulation of swine leukocyte antigen (SLA)-DR was observed in bone marrow-derived dendritic cells (BMDCs) and porcine alveolar macrophages (PAMs), whereas remarkable inhibition at the mRNA level was observed after infection by both PRRSV-1 and PRRSV-2 isolates. Notably, the inconsistency in SLA-DR expression between the mRNA and protein levels resulted from deubiquitination of SLA-DR via the ovarian tumor (OTU) domain of PRRSV NSP2, which inhibited ubiquitin-mediated degradation. Moreover, mass spectrometry-based immunopeptidome analysis identified immunopeptides originating from multiple PRRSV NSPs within SLA-DR of PRRSV-infected BMDCs. Meanwhile, these PRRSV NSP-derived immunopeptides could be specifically recognized by serum from PRRSV-infected piglets. Notably, certain NSP-derived immunopeptides characterized in vitro could be identified from PAMs or hilar lymph nodes from PRRSV-infected piglets. More importantly, an in vitro neutralizing assay indicated that serum antibodies against NSP immunopeptides were unable to neutralize PRRSV in vitro Conversely, certain structural protein (SP)-derived immunopeptides were identified and could be recognize by pig hyperimmune serum against PRRSV, which further indicates that the NSP-derived antibody response is nonprotective in vivo In conclusion, our data suggested that PRRSV infection interferes with major histocompatibility complex class II (MHC-II) molecule-mediated antigen presentation in antigen-presenting cells (APCs) via promoting SLA-DR expression to present immunopeptides from PRRSV NSPs, which contributes to the induction of non-NAbs in vivoIMPORTANCE PRRSV has haunted the swine industry for over 30 years since its emergence. Besides the limited efficacy of PRRSV modified live vaccines (MLVs) against heterogeneous PRRSV isolates, rapid induction of nonneutralizing antibodies (non-NAbs) against PRRSV NSPs after MLV immunization or wild-strain infection is one of the reasons why development of an effective vaccine has been hampered. By using in vitro-generated BMDCs as models to understand the antigen presentation process of PRRSV, we obtained data indicating that PRRSV infection of BMDCs promotes functional SLA-DR upregulation to present PRRSV NSP-derived immunopeptides for evoking a non-NAb response in vivo Our work not only uncovered a novel mechanism for interference in host antigen presentation by PRRSV but also revealed a novel insight for understanding the rapid production of nonneutralizing antibodies against PRRSV NSPs, which may have benefit for developing an effective vaccine against PRRSV in the future. CI - Copyright (c) 2020 American Society for Microbiology. FAU - Wu, Chunyan AU - Wu C AD - Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China. AD - Scientific Observing and Experimental Station of Veterinary Pharmacology and Veterinary Biotechnology, Ministry of Agriculture, Yangling, Shaanxi, China. FAU - Shi, Bingjun AU - Shi B AD - Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China. FAU - Yang, Di AU - Yang D AD - Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China. FAU - Zhang, Kun AU - Zhang K AD - Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China. FAU - Li, Jie AU - Li J AD - Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China. FAU - Wang, Jie AU - Wang J AD - Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China. FAU - Liu, Hongliang AU - Liu H AD - Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China. FAU - Zhao, Qin AU - Zhao Q AD - Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China. AD - Scientific Observing and Experimental Station of Veterinary Pharmacology and Veterinary Biotechnology, Ministry of Agriculture, Yangling, Shaanxi, China. FAU - Zhou, En-Min AU - Zhou EM AUID- ORCID: 0000-0001-8942-013X AD - Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China zhouem@nwsuaf.edu.cn nanyuchen2015@nwsuaf.edu.cn. AD - Scientific Observing and Experimental Station of Veterinary Pharmacology and Veterinary Biotechnology, Ministry of Agriculture, Yangling, Shaanxi, China. FAU - Nan, Yuchen AU - Nan Y AUID- ORCID: 0000-0002-4442-8004 AD - Department of Preventive Veterinary Medicine, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China zhouem@nwsuaf.edu.cn nanyuchen2015@nwsuaf.edu.cn. AD - Scientific Observing and Experimental Station of Veterinary Pharmacology and Veterinary Biotechnology, Ministry of Agriculture, Yangling, Shaanxi, China. LA - eng PT - Journal Article PT - Research Support, Non-U.S. Gov't DEP - 20201014 PL - United States TA - J Virol JT - Journal of virology JID - 0113724 RN - 0 (Antibodies, Viral) RN - 0 (Histocompatibility Antigens Class II) RN - 0 (Viral Nonstructural Proteins) SB - IM MH - Amino Acid Sequence MH - Animals MH - Antibodies, Viral/*biosynthesis MH - *Antigen Presentation MH - Bone Marrow Cells/immunology/virology MH - Dendritic Cells/immunology/virology MH - Gene Expression Regulation MH - Histocompatibility Antigens Class II/genetics/*immunology MH - Host-Pathogen Interactions/genetics/*immunology MH - Immunity, Humoral MH - Lymph Nodes/immunology/virology MH - Macrophages, Alveolar/immunology/virology MH - Porcine Reproductive and Respiratory Syndrome/genetics/*immunology/pathology/virology MH - Porcine respiratory and reproductive syndrome virus/growth & development/*immunology/pathogenicity MH - Proteolysis MH - Signal Transduction MH - Swine MH - Ubiquitination MH - Viral Nonstructural Proteins/genetics/*immunology PMC - PMC7565617 OTO - NOTNLM OT - MHC-II molecules OT - PRRSV OT - SLA-DR OT - antigen presentation OT - mass spectrometry OT - nonneutralizing antibodies EDAT- 2020/08/17 06:00 MHDA- 2020/12/31 06:00 PMCR- 2021/04/14 CRDT- 2020/08/16 06:00 PHST- 2020/07/13 00:00 [received] PHST- 2020/08/03 00:00 [accepted] PHST- 2020/08/17 06:00 [pubmed] PHST- 2020/12/31 06:00 [medline] PHST- 2020/08/16 06:00 [entrez] PHST- 2021/04/14 00:00 [pmc-release] AID - JVI.01423-20 [pii] AID - 01423-20 [pii] AID - 10.1128/JVI.01423-20 [doi] PST - epublish SO - J Virol. 2020 Oct 14;94(21):e01423-20. doi: 10.1128/JVI.01423-20. Print 2020 Oct 14.