Infectious agents causing aborted fetus problems in domestic pigs were investigated in this study. More than 10 different infectious agents were known to cause abortion in swine and the major eight viruses among them ...Infectious agents causing aborted fetus problems in domestic pigs were investigated in this study. More than 10 different infectious agents were known to cause abortion in swine and the major eight viruses among them were inspected. One hundred twelve samples of aborted fetuses from nine provinces in South Korea were collected during April to November, 2013 in this study for the diagnosis of infectious agents causing abortions in pigs. Eight major infection viruses were examined in this study mainly using various diagnostic kits and reverse transcriptase polymerase chain reaction （RT-PCR）. Positive rate of the detection differed from each viruses. In this study, the main focus was the porcine reproductive and respiratory syndrome virus （PRRSV）, which took the second large portion in the positive rate of detection, and then its ORF5 gene was compared with modified live virus （MLV） vaccine strain to figure out the influence of vaccine on disease. Between four positive samples＇ sequence, two of them were 99.9%-100% similar to MLV vaccine strain and two other samples were 88.6%-92.7% similar. Similarity rate of the sequences between the vaccine and virus from aborted fetuses are very crucial, because it implies that abortion in swine can be made due to the usage of vaccine not only by the infection of field virus, and if MLV vaccine actually do have an impact on the infection, usage of the vaccine should be reconsidered.展开更多
Brucella abortus is a zoonotic Gram-negative pathogen that causes brucelosis in ruminants and humans. Toll-like receptors （TLRs） recognize Brucella abortus and initiate antigen-presenting cell activities that affect...Brucella abortus is a zoonotic Gram-negative pathogen that causes brucelosis in ruminants and humans. Toll-like receptors （TLRs） recognize Brucella abortus and initiate antigen-presenting cell activities that affect both innate and adaptive immunity. In this study, we focused on recombinant Brucella cell-surface protein 31 （rBCSP31） to determine its effects on mouse macrophages. Our results demonstrated that rBCSP31 induced TNF-α, IL-6 and IL-12p40 production, which depended on the activation of mitogen-activated protein kinases （MAPKs） by stimulating the rapid phosphorylation of p38 and JNK and the activation of transcription factor NF-KB in macrophages. In addition, continuous exposure （〉24 h） of RAW264.7 cells to rBCSP31 significantly enhanced I FN-y-induced expression of MHC-II and the ability to present rBCSP31 peptide to CD4＋ T cells. Furthermore, we found that rBCSP31 could interact with both TLR2 and TLR4. The rBCSP31-induced cytokine production by macrophages from TLR2-/- and TLR4-/- mice was lower than that from C57BL/6 macrophages, and the activation of NF-KB and MAPKs was attenuated in macrophages from TLR2-/- and TLR4-/- mice. In addition, CD4＋ T cells from C57BL/6 mice immunized with rBCSP31 produced higher levels of IFN-y and IL-2 compared with CD4＋ T cells from TLR2-/- and TLR4-/- mice. Macrophages from immunized C57BL/6 mice produced higher levels of IL-12p40 than those from TLR2-/- and TLR4-/- mice. Furthermore, immunization with rBCSP31 provided better protection in C57BL/6 mice than in TLR2-/- and TLR4-/- mice after B. abortus 2308 challenge. These results indicate that rBCSP31 is a TLR2 and TLR4 agonist that induces cytokine production, upregulates macrophage function and induces the Thl immune response.展开更多
文摘Infectious agents causing aborted fetus problems in domestic pigs were investigated in this study. More than 10 different infectious agents were known to cause abortion in swine and the major eight viruses among them were inspected. One hundred twelve samples of aborted fetuses from nine provinces in South Korea were collected during April to November, 2013 in this study for the diagnosis of infectious agents causing abortions in pigs. Eight major infection viruses were examined in this study mainly using various diagnostic kits and reverse transcriptase polymerase chain reaction （RT-PCR）. Positive rate of the detection differed from each viruses. In this study, the main focus was the porcine reproductive and respiratory syndrome virus （PRRSV）, which took the second large portion in the positive rate of detection, and then its ORF5 gene was compared with modified live virus （MLV） vaccine strain to figure out the influence of vaccine on disease. Between four positive samples＇ sequence, two of them were 99.9%-100% similar to MLV vaccine strain and two other samples were 88.6%-92.7% similar. Similarity rate of the sequences between the vaccine and virus from aborted fetuses are very crucial, because it implies that abortion in swine can be made due to the usage of vaccine not only by the infection of field virus, and if MLV vaccine actually do have an impact on the infection, usage of the vaccine should be reconsidered.
文摘Brucella abortus is a zoonotic Gram-negative pathogen that causes brucelosis in ruminants and humans. Toll-like receptors （TLRs） recognize Brucella abortus and initiate antigen-presenting cell activities that affect both innate and adaptive immunity. In this study, we focused on recombinant Brucella cell-surface protein 31 （rBCSP31） to determine its effects on mouse macrophages. Our results demonstrated that rBCSP31 induced TNF-α, IL-6 and IL-12p40 production, which depended on the activation of mitogen-activated protein kinases （MAPKs） by stimulating the rapid phosphorylation of p38 and JNK and the activation of transcription factor NF-KB in macrophages. In addition, continuous exposure （〉24 h） of RAW264.7 cells to rBCSP31 significantly enhanced I FN-y-induced expression of MHC-II and the ability to present rBCSP31 peptide to CD4＋ T cells. Furthermore, we found that rBCSP31 could interact with both TLR2 and TLR4. The rBCSP31-induced cytokine production by macrophages from TLR2-/- and TLR4-/- mice was lower than that from C57BL/6 macrophages, and the activation of NF-KB and MAPKs was attenuated in macrophages from TLR2-/- and TLR4-/- mice. In addition, CD4＋ T cells from C57BL/6 mice immunized with rBCSP31 produced higher levels of IFN-y and IL-2 compared with CD4＋ T cells from TLR2-/- and TLR4-/- mice. Macrophages from immunized C57BL/6 mice produced higher levels of IL-12p40 than those from TLR2-/- and TLR4-/- mice. Furthermore, immunization with rBCSP31 provided better protection in C57BL/6 mice than in TLR2-/- and TLR4-/- mice after B. abortus 2308 challenge. These results indicate that rBCSP31 is a TLR2 and TLR4 agonist that induces cytokine production, upregulates macrophage function and induces the Thl immune response.
