title: Suppressor of cytokine signaling 3 plays an important role in porcine circovirus type 2 subclinical infection by downregulating proinflammatory responses.
abstract: Porcine circovirus type 2 (PCV2) causes porcine circovirus-associated diseases and usually evokes a subclinical infection, without any obvious symptoms, in pigs. It remains unclear how PCV2 leads to a subclinical infection. In this study, we found that peripheral blood mononuclear cells (PBMCs) from PCV2-challenged piglets with no significant clinical symptoms exhibited increased expression of suppressor of cytokine signaling (SOCS) 3, but no significant changes in the expression of the proinflammatory cytokines interleukin (IL)-6 and tumor necrosis factor (TNF)-α; this differed from piglets that displayed significant clinical symptoms. IL-6- and TNF-α-mediated signalings were inhibited in PBMCs from subclinical piglets. Elevated SOCS3 levels inhibited IL-6- and TNF-α-mediated NF-kappa-B inhibitor alpha degradation in PBMCs and PK-15 cells. SOCS3 production was also increased in PCV2-infected PK-15 porcine kidney cells, and IL-6 and TNF-α production that was induced by PCV2 in PK-15 cells was significantly increased when SOCS3 was silenced by a small interfering RNA. SOCS3 interacted with signal transducer and activator of transcription 3 and TNF-associated receptor-associated factor 2, suggesting mechanisms by which SOCS3 inhibits IL-6 and TNF-α signaling. We conclude that SOCS3 plays an important role in PCV2 subclinical infection by suppressing inflammatory responses in primary immune cells.
authors: Key Laboratory of Animal Diseases Diagnostic and Immunology, Ministry of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China.
authors: Xuejiao
authors: X
authors: Zhu
authors: Key Laboratory of Animal Diseases Diagnostic and Immunology, Ministry of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China.
authors: Juan
authors: J
authors: Bai
authors: Key Laboratory of Animal Diseases Diagnostic and Immunology, Ministry of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China.
authors: Panrao
authors: P
authors: Liu
authors: Key Laboratory of Animal Diseases Diagnostic and Immunology, Ministry of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China.
authors: Xianwei
authors: X
authors: Wang
authors: Key Laboratory of Animal Diseases Diagnostic and Immunology, Ministry of Agriculture, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China.|Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, China.
authors: Ping
authors: P
authors: Jiang
mesh_terms: D000818:Animals; D058345:Asymptomatic Infections; D002460:Cell Line; D018173:Circoviridae Infections / Q000235:genetics* / Q000276:immunology / Q000821:virology; D017925:Circovirus / Q000276:immunology* / Q000472:pathogenicity; D004847:Epithelial Cells / Q000276:immunology / Q000821:virology; D005786:Gene Expression Regulation; D054884:Host-Pathogen Interactions / Q000276:immunology; D015850:Interleukin-6 / Q000235:genetics* / Q000276:immunology; D007963:Leukocytes, Mononuclear / Q000276:immunology / Q000821:virology; D000072000:NF-KappaB Inhibitor alpha / Q000235:genetics / Q000276:immunology; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D050796:STAT3 Transcription Factor / Q000235:genetics* / Q000276:immunology; D012720:Severity of Illness Index; D015398:Signal Transduction; D000071223:Suppressor of Cytokine Signaling 3 Protein / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000276:immunology; D013552:Swine; D013553:Swine Diseases; D047992:TNF Receptor-Associated Factor 2 / Q000235:genetics / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics* / Q000276:immunology
chemical_list: D015850:Interleukin-6; D034741:RNA, Small Interfering; D050796:STAT3 Transcription Factor; D000071223:Suppressor of Cytokine Signaling 3 Protein; D047992:TNF Receptor-Associated Factor 2; D014409:Tumor Necrosis Factor-alpha; D000072000:NF-KappaB Inhibitor alpha