Serological and molecular investigation of porcine sapovirus infection in piglets in Xinjiang, China.

Porcine sapovirus (PoSaV) is one of the important pathogens that cause acute gastroenteritis in piglets. A survey on the infection and epidemic status of PoSaV in Xinjiang Province, Northwest China, was conducted in this study. We applied indirect viral protein 1 (VP1)-ELISA method to detect specific antibodies in 1218 serum samples of 3-month-old piglets collected from eight regions in Xinjiang during 2013-2014 and also detected PoSaV in 146 diarrhea stools of piglets in these eight regions using RT-PCR technology. The results showed that the PoSaV-serological positive rates in piglets in eight different regions in Xinjiang were between 32.82 and 47.06% with a mean rate of 37.68%. The average positive rate of PCR in stools of piglets was 3.42%. Sequencing and comparative analysis of five PCR-amplified DNA fragments revealed that four epidemic strains of PoSaV (swine/XJ-KO1, swine/XJ-AK2, swine/XJ-KS1, and swine/XJ-SHZ1) shared high nucleotide and amino acid identities with Cowden strain, while strain swine/XJ-AK1 shared higher high identities with Po/OH-JJ681/2000/US isolate. Phylogenetic clustering further verified that the epidemic strains of PoSaVs, i.e., swine/XJ-KO1, swine/XJ-AK2, swine/XJ-KS1, and swine/XJ-SHZ1, belong to genogroup (GIII) while swine/XJ-AK1 belongs to GVI. This survey confirmed for the first time that PoSaV infection was common in piglets in Xinjiang, China, and that the epidemic strains exist at least in both GIII and GVI clusters. This study provided the useful epidemiological data for scientific control and prevention of this disease.

Serological and molecular survey of sheep infected with Mycoplasma ovipneumoniae in Xinjiang, China.

Mycoplasma pneumonia is one of the most important infectious diseases that threaten sheep production. In order to investigate the epidemic status of Mycoplasma ovipneumoniae infection in sheep, indirect hemagglutination assay was used to analyze 1679 serum samples collected from four different breeds of sheep (Kazak sheep, Hu sheep, Merino sheep, and Duolang sheep) in six regions in Xinjiang between 2012 and 2014. One thousand one hundred sixty-nine sheep nasal swabs and 180 lungs were PCR analyzed. The results showed that the average positive rates of the serum samples were 17.75 %. The positive rates were between 9.76 and 30.61 % in the four breeds. Among them, the Hu sheep had a significantly higher rate than other breeds (P < 0.05). The average positive rates of nasal swabs and lungs were 10.18 and 28.89 %, respectively. Based on the phylogenetic trees of 16S RNA gene, the isolates were closest to those strains isolated from inland areas of China, indicating that these epidemic isolates came from the trans-province introductions. Our survey suggests that quarantine is necessary for sheep imported from inland, and effective immunization should be implemented in sheep susceptible to M. ovipneumoniae in Xinjiang, China.

Prevalence of hydatid cysts in livestock animals in Xinjiang, China.

Hydatid worms, hosted by humans and animals, impose serious human health risk and cause significant livestock production loss. To better understand the disease infection status in Xinjiang, China, we investigated the disease epidemics in 4 livestock animals, i.e., cattle, sheep (both sheep and goat), camels, and horses, slaughtered at the abattoirs in Urumqi, Yining, Tacheng, and Altay areas. The results showed that the animals were infected at different rates, in the order of sheep (9.8%), cattle (8.4%), camels (6.8%), and horses (4.3%). The infection rates were found to be different between the abattoirs in various regions even for the same animals. For sheep, the rates increased significantly as the animals grew older. It was 1.9% before 1 year of age and increased to 8.2% in the age of 1-2 years, and further increased to 12.3% when the animals were 3-4 years old, and reached 17.2% when they were 5-6 year old. Sheep older than 6 years had an infection rate of 19.5%. This study demonstrates that the 4 livestock animals in the pastoral areas in Xinjiang were infected by the parasites to various extend. This study is the first systematic investigation of the hydatid worms in various livestock animals in Xinjiang, China, which provides epidemiological information about the infection of hydatid worms in livestock, and is valuable in developing strategies for prevention and control of the hydatid disease.

A serological survey of Akabane virus infection in cattle and sheep in northwest China.

PURPOSE: Akabane disease characterized mainly by fetal damage is a ruminant disease caused by insect-transmitted Akabane virus infection. METHODS: We investigated Akabane disease using serum neutralization tests in 446 blood samples collected from 187 cattle and 259 sheep of Xinjiang province, northwest China. RESULTS: (1) The overall prevalence rate of neutralizing antibody was 19.06 % (85/446), (2) the prevalence rates of Akabane disease in cattle and sheep were 20.32 % (38/187) and 18.15 % (47/259), respectively, (3) the disease prevalence rates were not significantly different between cattle and sheep, but significantly different among samples collected from different sampling months, (4) the disease was most prevalent in July when mosquitoes and culicoides were most active, and (5) the disease prevalence rates were significantly different between individuals with abortion experience and without abortion experience (P < 0.05), suggesting that Akabane virus infection may significantly increase abortion risk in cattle and sheep. CONCLUSIONS: To our knowledge, this is the first report confirming that Akabane virus infection is common in cattle and sheep of Xinjiang province, northwest China and providing useful epidemiological information for cattle and sheep abortion prevention and control.

Inhibition of foot-and-mouth disease virus replication in vitro and in vivo by small interfering RNA.

By using bioinformatics computer programs, all foot-and-mouth disease virus (FMDV) genome sequences in public-domain databases were analyzed. Based on the results of homology analysis, 2 specific small interfering RNA (siRNA) targeting homogenous 3D and 2B1 regions of 7 serotypes of FMDV were prepared and 2 siRNA-expression vectors, pSi-FMD2 and pSi-FMD3, were constructed. The siRNA-expressing vectors were used to test the ability of siRNAs to inhibit virus replication in baby hamster kidney (BHK-21) cells and suckling mice, a commonly used small animal model. The results demonstrated that transfection of BHK-21 cells with siRNA-expressing plasmids significantly weakened the cytopathic effect (CPE). Moreover, BHK-21 cells transiently transfected with short hairpin RNA (shRNA)-expressing plasmids were specifically resistant to the infection of the FMDV serotypes A, O, and Asia I and this the antiviral effects persisted for almost 48 hours. We measured the viral titers, the 50% tissue culture infective dose (TCID50) in cells transfected with anti-FMDV siRNAs was found to be lower than that of the control cells. Furthermore, subcutaneous injection of siRNA-expressing plasmids in the neck of the suckling mice made them less susceptible to infection with O, and Asia I serotypes of FMDV.

Preparation and immunogenicity evaluation of mRNA vaccine against porcine epidemic diarrhea / 生物工程学报

Porcine epidemic diarrhea (PED) is a highly contagious disease that causes high mortality in suckling piglets. Although several licensed inactivated and live attenuated vaccines were widely used, the infection rate remains high due to unsatisfactory protective efficacy. In this study, mRNA vaccine candidates against PED were prepared, and their immunogenicity was evaluated in mice and pregnant sows. The mRNA PED vaccine based on heterodimer of viral receptor binding region (RBD) showed good immunogenicity. It elicited robust humoral and cellular immune responses in mice, and the neutralizing antibody titer reached 1:300 after a single vaccination. Furthermore, it induced neutralizing antibody level similar to that of the inactivated vaccine in pregnant sows. This study developed a new design of PED vaccine based on the mRNA-RBD strategy and demonstrated the potential for clinical application.

Expression and clinical significance of GBP1 in pulmonary tuberculosis / 安徽医科大学学报

Objective@#To investigate the expression pattern，underlying function and clinical significance of Guanylate-binding protein 1 ( GBP1) in pulmonary tuberculosis ( pTB) ．@*Methods@#Immunohistochemical staining was applied to detect the expression of GBP1 in pTB specimensand control samples． Combined with Gene Expression Omnibus ( GEO) datasets ，including GSE83456 and GSE34608，receiver operating characteristic ( ROC) curve was depicted to assess the diagnostic value of GBP1 in pTB．Then，the correlation between GBP1 and related regulatory factors was analyzed by protein-protein interaction network ( PPI) ; Finally，the potential molecular mechanism of GBP1 in pTB was probed by Gene Set Enrichment Analysis( GSEA) . @*Results@# Compared with the control group，GBP1 was significantly overexpressed in human pTB samples，including lung tissue and blood．The positive rate of GBP1 protein in pTB was 73. 9% . ROC curve analysis revealed that GBP1 might have important value in early diagnosis of pTB．GSEA analysis suggested that the hyper-expression of GBP1 was closely related to the host inflammatory response，IFN-γ/ α signaling pathway and TNF-α/ IL-6 signal transduction．@*Conclusion@# GBP1 is highly expressed in pTB tissues and is involved in the process of inflammatory response and host anti-tuberculosis infection ; GBP1 may be used as an early diagnostic marker or therapeutic target for pTB.

A combined application of molecular docking technology and indirect ELISA for the serodiagnosis of bovine tuberculosis

Background@#There is an urgent need to find reliable and rapid bovine tuberculosis (bTB) diagnostics in response to the rising prevalence of bTB worldwide. Toll-like receptor 2 (TLR2) recognizes components of bTB and initiates antigen-presenting cells to mediate humoral immunity. Evaluating the affinity of antigens with TLR2 can form the basis of a new method for the diagnosis of bTB based on humoral immunity. @*Objectives@#To develop a reliable and rapid strategy to improve diagnostic tools for bTB. @*Methods@#In this study, we expressed and purified the sixteen bTB-specific recombinant proteins in Escherichia coli. The two antigenic proteins, MPT70 and MPT83, which were most valuable for serological diagnosis of bTB were screened. Molecular docking technology was used to analyze the affinity of MPT70, MPT83, dominant epitope peptide of MPT70 (M1), and dominant epitope peptide MPT83 (M2) with TLR2, combined with the detection results of enzyme-linked immunosorbent assay to evaluate the molecular docking effect. @*Results@#The results showed that interaction surface Cα-atom root mean square deviation of proteins (M1, M2, MPT70, MPT83)-TLR2 protein are less than 2.5 A, showing a high affinity.It is verified by clinical serum samples that MPT70, MPT83, MPT70-MPT83 showed good diagnostic potential for the detection of anti-bTB IgG and M1, M2 can replace the whole protein as the detection antigen. @*Conclusions@#Molecular docking to evaluate the affinity of bTB protein and TLR2 combined with ELISA provides new insights for the diagnosis of bTB.

Nucleomodulin BspJ as an effector promotes the colonization of Brucella abortus in the host

Background@#Brucella infection induces brucellosis, a zoonotic disease. The intracellular circulation process and virulence of Brucella mainly depend on its type IV secretion system (T4SS) expressing secretory effectors. Secreted protein BspJ is a nucleomodulin of Brucella that invades the host cell nucleus. BspJ mediates host energy synthesis and apoptosis through interaction with proteins. However, the mechanism of BspJ as it affects the intracellular survival of Brucella remains to be clarified. @*Objectives@#To verify the functions of nucleomodulin BspJ in Brucella's intracellular infection cycles. @*Methods@#Constructed Brucella abortus BspJ gene deletion strain (B. abortus ΔBspJ) and complement strain (B. abortus pBspJ) and studied their roles in the proliferation of Brucella both in vivo and in vitro. @*Results@#BspJ gene deletion reduced the survival and intracellular proliferation of Brucellaat the replicating Brucella-containing vacuoles (rBCV) stage. Compared with the parent strain, the colonization ability of the bacteria in mice was significantly reduced, causing less inflammatory infiltration and pathological damage. We also found that the knockout of BspJ altered the secretion of cytokines (interleukin [IL]-6, IL-1β, IL-10, tumor necrosis factor-α, interferon-γ) in host cells and in mice to affect the intracellular survival of Brucella. @*Conclusions@#BspJ is extremely important for the circulatory proliferation of Brucella in the host, and it may be involved in a previously unknown mechanism of Brucella's intracellular survival.

miR-200c-141 Enhances Sheep Kidney Cell Reprogramming into Pluripotent Cells by Targeting ZEB1

Background and Objectives@#Sheep-induced pluripotent stem cells (siPSCs) have low reprogramming efficiency, thereby hampering their use in biotechnology and agriculture. Several studies have shown that some microRNAs play an important role in promoting somatic reprogramming in mouse and human. In this study, we investigated the effect of miR-200c-141 on somatic reprogramming in sheep and explored the mechanism of promoting the reprogramming. @*Methods@#and Results: The lentivirus system driven by tetracycline (TET)-on carrying Oct4, Sox2, c-Myc, Klf4, Nanog, Lin28, hTERT, and SV40LT (OSKMNLST) could reprogram sheep kidney cells into pluripotent cells. Overexpression of miR-200c-141 in combination with OSKMNLST could significantly improve the efficiency of sheep iPSC generation (p＜0.01). Sheep iPSCs derived from miR-200c-141 showed embryonic stem cell (ESC)-like pluripotent properties, were positive for alkaline phosphatase and some pluripotent markers by quantitative real-time PCR (qRT-PCR) and immunofluorescence, and were able to differentiate into three germ layers in vitro. Oar-miR-200c was transfected into HEK293FT cells and was able to target the zinc finger E-box-binding homeobox 1 (ZEB1) 3’UTR using dual luciferase reporting analysis. Overexpression of oar-miR-200c in SKCs significantly reduced the expression of ZEB1, but increased the expression of E-cadherin by qRT-PCR and western blotting analysis. @*Conclusions@#These results suggest that miR-200c-141 can promote the reprogramming of sheep somatic cells to iPSCs, and oar-miR-200c targeted ZEB1 3’UTR, significantly decreased expression of ZEB1, and increased expression of E-cadherin. Oar-miR-200c may improve the MET process by affecting the TGF-β signaling pathway, thus improving the efficiency of somatic cell reprogramming in sheep.