Activation of the TLR/MyD88/NF-κB signal pathway contributes to changes in IL-4 and IL-12 production in piglet lymphocytes infected with porcine circovirus type 2 in vitro.
Porcine circovirus type 2 (PCV2) causes immunosuppression in pigs. One causative factor is an imbalance in cytokine levels in the blood and lymphoid tissues. Many studies have reported changes in cytokine production, but the regulatory mechanisms involved have not yet been elucidated. In this study, we investigated alteration and regulation of IL-4 and IL-12 production in lymphocytes following incubation with PCV2 in vitro. The levels of IL-4 decreased and levels of IL-12 increased in lymphocyte supernatants, and the DNA-binding activity of NF-κB and the expression of p65 in the nucleus and p-IκB in the cytoplasm of lymphocytes increased after incubation with PCV2. However, these effects were reversed when lymphocytes were coincubated with PCV2 and the NF-κB inhibitor BAY11-7082. In addition, the expression of MyD88 protein increased and the expression of mRNA for the toll-like receptors (TLRs) TLR2, TLR3, TLR4 and TLR9 was upregulated when lymphocytes were incubated with PCV2. However, no change was seen in TLR7 and TLR8 mRNA expression. In conclusion, this study showed that PCV2 induced a decrease in IL-4 and an increase in IL-12 production in lymphocytes, and these changes were regulated by the TLR-MyD88-NF-κB signal pathway.
College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.
Dianning
D
Duan
College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.
Shuxia
S
Zhang
College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.
Xiaolin
X
Li
College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.
Hua
H
Guo
College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.
Mengmeng
M
Chen
College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.
Yaqun
Y
Zhang
College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.
Junyuan
J
Han
College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.
Yingjun
Y
Lv
D000704:Analysis of Variance; D000818:Animals; D015153:Blotting, Western; D017931:DNA Primers / Q000235:genetics; D024202:Electrophoretic Mobility Shift Assay; D005434:Flow Cytometry; D019084:Fluorescent Antibody Technique, Indirect; D005786:Gene Expression Regulation / Q000276:immunology*; D007108:Immune Tolerance / Q000276:immunology*; D018664:Interleukin-12 / Q000096:biosynthesis / Q000276:immunology; D015847:Interleukin-4 / Q000096:biosynthesis / Q000276:immunology; D008214:Lymphocytes / Q000276:immunology* / Q000821:virology*; D053594:Myeloid Differentiation Factor 88 / Q000378:metabolism; D016328:NF-kappa B / Q000378:metabolism; D009570:Nitriles; D009841:Oligonucleotides / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D015398:Signal Transduction / Q000276:immunology*; D013450:Sulfones; D013552:Swine; D051193:Toll-Like Receptors / Q000378:metabolism
C434003:3-(4-methylphenylsulfonyl)-2-propenenitrile; D017931:DNA Primers; D053594:Myeloid Differentiation Factor 88; D016328:NF-kappa B; D009570:Nitriles; D009841:Oligonucleotides; D013450:Sulfones; D051193:Toll-Like Receptors; D018664:Interleukin-12; D015847:Interleukin-4