The Effect Of Prrsv-specific Peptides On The Secretion Of TGF-?1?IL-10 And IL-12 In Swine Tissue Lymphocyte After CSF And PRRS Vaccination

Porcine reproductive and respiratory syndrome(PRRS)is a fulminating infectious disease spreads quickly among the herd of swine,caused by porcine reproductive and respiratory syndrome virus(PRRSV),commonly known as “blue ear disease of porcine” and “Mystery disease(MSD)”.PRRS spreads around the world in a few years from the first appearance and becomes the major infectious diseases of prevention and control.PRRS often infects with other infectious diseases such as classical swine fever(CSF),causing complex clinical symptoms and pathological changes.The increased mortality of diseased pigs makes prevention and treatment of the disease more difficult.In the course of PRRSV infection,IL-12 mainly involves in early antiviral adaptive immunity and induces the cellular immunity.TGF-?1 and IL-10 affect the immune suppression process.The experimental animals inoculate the CSFV,PRRSV vaccine according to the specific immune procedure,establishing the experimental pig model with two vaccines.Four kinds of PRRSV specific peptides designed independently and commercially synthesized stimulate the lymphocytes isolated from bone marrow,thymus,hilar lymph node and spleen of each experimental pig.The contents of TGF-?1,IL-10 and IL-12 after 24 h and 48 h of peptides stimulation are detected by using the Porcine ELISA test kit respectively.The aim of the experiment is to discuss the secretion characteristics of three cytokines,reflecting the nature of the immune response of the animal body and providing experimental data for the prevention and control of PRRS.Results of the 24 h peptide stimulation group shows that T lymphocytes isolated from bone marrow are stimulated by PRRSV-specific G peptides and N peptides,and the secretion of TGF-?1 is lower than that of the blank control group,and the difference is significant(P<0.05),The secretion of IL-10 is lower than that of the blank control group,and the difference is significant(P<0.05),The secretion of IL-12 is decreased compared with the blank control group,especially in PRRSV-specific N peptides stimulation(P<0.05).T lymphocytes isolated from thymus are stimulated by PRRSV-specific G peptides and N peptides,and the secretion of TGF-?1 is lower than that of the blank control group,and the difference is significant(P<0.05),The secretion of IL-10 is lower than that of the blank control group,and the difference is significant(P<0.05),The secretion of IL-12 is lower than that of the blank control group,and the difference is not significant.The secretion of TGF-?1 is lower than that of the blank control group,and the difference is significant(P<0.05)after the T lymphocytes isolated from the pulmonary portal lymph node are stimulated by PRRSV-specific G peptides and N peptides,The secretion of IL-10 is lower than that of the blank control group,and the difference is not significant,The secretion of IL-12 is lower than that of the blank control group,and the difference is significant(P<0.05).T lymphocytes isolated from the spleen are stimulated by PRRSV-specific G peptides and N peptides,and the secretion of TGF-?1 is lower than that of the blank control group,and the difference is not significant,The secretion of IL-10 is decreased compared with the blank control group after the stimulation of PRRSV-specific G peptides(P<0.05),The secretion of IL-12 is increased after the stimulation of PRRSV-specific N peptides,and increased compared with the control group,especially in PRRSV-specific N2 peptide stimulation(P<0.05).Results of the 48 h peptide stimulation group shows that T lymphocytes isolated from bone marrow are stimulated by PRRSV-specific G peptides and N peptides,and the secretion of TGF-?1 is lower than that of the blank control group,and the difference is significant(P<0.05),The secretion of IL-10 is decreased compared with the blank control group,especially in PRRSV-specific N peptides stimulation(P<0.05),The secretion of IL-12 is decreased in PRRSV-specific G2,N1 and N2 peptides,and the difference is not significant compared with the blank control group.T lymphocytes isolated from thymus are stimulated by PRRSV-specific G peptides and N peptides,and the secretion of TGF-?1 is lower than that of the blank control group,and the difference is significant(P<0.05),The secretion of IL-10 is decreased compared with the blank control group,especially in PRRSV-specific N peptides stimulation(P<0.05),The secretion of IL-12 is decreased compared with the blank control group,and the difference is not significant.The secretion of TGF-?1 is lower than that of the blank control group,and the difference is significant(P<0.05)after the T lymphocytes isolated from the pulmonary portal lymph node are stimulated by PRRSV-specific G peptides and N peptides,The secretion of IL-10 is lower than that of the blank control group,and the difference is significant(P<0.05),The secretion of IL-12 is decreased compared with the blank control group,especially in PRRSV-specific N1 peptide stimulation(P<0.05).T lymphocytes isolated from the spleen are stimulated by PRRSV-specific G peptides,and the secretion of TGF-?1 is lower than that of the blank control group,and the difference is not significant,The secretion of IL-10 is decreased compared with the blank control group after the stimulation of PRRSV-specific G peptides,and the difference is not significant.The secretion of IL-12 is increased after the stimulation of PRRSV-specific G peptides and N peptides,compared with the blank control group,especially in PRRSV-specific N2 peptide stimulation(P<0.05).The results show that the immune system is in a relatively sensitive immune response state and is able to respond to the stimulation of four PRRSV-specific peptides,when the experimental pigs are successfully immunized with CSF and PRRS vaccines.The four PRRSV-specific peptides could inhibit the secretion of TGF-?1 and IL-10 in bone marrow,thymus and hilar lymph nodes,weaken the immunosuppressive effect on the body.There is a significant tendency promoting the secretion of IL-12 after the stimulation of G1 and G2 peptides.In addition,It can be seen from the data that the N1,and N2 peptides on the secretion of cytokines in the tissues and organs are more significant than the G1 and G2 peptides and have a stronger effect.The experiment combined with the previous results can provide theoretical and data support for the development of PRRSV synthetic peptide vaccines.