African swine fever virus MGF505-6R attenuates type I interferon production by targeting STING for degradation.

African swine fever (ASF) is an acute hemorrhagic and devastating infectious disease affecting domestic pigs and wild boars. It is caused by the African swine fever virus (ASFV), which is characterized by genetic diversity and sophisticated immune evasion strategies. To facilitate infection, ASFV encodes multiple proteins to antagonize host innate immune responses, thereby contributing to viral virulence and pathogenicity. The molecular mechanisms employed by ASFV-encoded proteins to modulate host antiviral responses have not been comprehensively elucidated. In this study, it was observed that the ASFV MGF505-6R protein, a member of the multigene family 505 (MGF505), effectively suppressed the activation of the interferon-beta (IFN-ß) promoter, leading to reduced mRNA levels of antiviral genes. Additional evidence has revealed that MGF505-6R antagonizes the cGAS-STING signaling pathway by interacting with the stimulator of interferon genes (STING) for degradation in the autophagy-lysosomal pathway. The domain mapping revealed that the N-terminal region (1-260aa) of MGF505-6R is the primary domain responsible for interacting with STING, while the CTT domain of STING is crucial for its interaction with MGF505-6R. Furthermore, MGF505-6R also inhibits the activation of STING by reducing the K63-linked polyubiquitination of STING, leading to the disruption of STING oligomerization and TANK binding kinase 1 (TBK1) recruitment, thereby impairing the phosphorylation and nuclear translocation of interferon regulatory factor 3 (IRF3). Collectively, our study elucidates a novel strategy developed by ASFV MGF505-6R to counteract host innate immune responses. This discovery may offer valuable insights for further exploration of ASFV immune evasion mechanisms and antiviral strategies.

A self-assembled nanoparticle vaccine based on pseudorabies virus glycoprotein D induces potent protective immunity against pseudorabies virus infection.

Pseudorabies virus (PRV) mainly causes pseudorabies (PR) or Aujeszky's disease in pigs and can infect humans, raising public health concerns about zoonotic and interspecies transmission of PR. With the emergence of PRV variants in 2011, the classic attenuated PRV vaccine strains have failed to protect many swine herds against PR. Herein, we developed a self-assembled nanoparticle vaccine that induces potent protective immunity against PRV infection. PRV glycoprotein D (gD) was expressed using the baculovirus expression system and further presented on the lumazine synthase (LS) 60-meric protein scaffolds via the SpyTag003/SpyCatcher003 covalent coupling system. In mouse and piglet models, LSgD nanoparticles emulsified with the ISA 201VG adjuvant elicited robust humoral and cellular immune responses. Furthermore, LSgD nanoparticles provided effective protection against PRV infection and eliminated pathological symptoms in the brain and lungs. Collectively, the gD-based nanoparticle vaccine design appears to be a promising candidate for potent protection against PRV infection.

Efficient mucosal vaccination of a novel classical swine fever virus E2-Fc fusion protein mediated by neonatal Fc receptor.

Classical swine fever (CSF) remains one of the most important highly contagious and fatal viral disease of swine with high morbidity and mortality. CSF is caused by classical swine fever virus (CSFV), a small, enveloped RNA virus of the genus Pestivirus. The aim of this study was to construct the a novel CSFV Fc-fusion recombinant protein and evaluate the efficacy as a vaccine against CSFV. Here, we obtained a novel subunit vaccine expressing CSFV E2 recombinant fusion protein in CHO-S cells. Functional analysis revealed that CSFV Fc-fusion recombinant protein (CSFV-E2-Fc) could bind to FcγRI on antigen-presenting cells (APCs) and significantly increase IgA levels in serum and feces, inducing stronger mucosal immune response in swine. Additionally, CSFV-E2-Fc immunization enhanced CSFV-specific T cell immune response with a Th1-like pattern of cytokine secretion, remarkably stimulated the Th1-biased cellular immune response and humoral immune response. Further, the protective effects of CSFV-E2-Fc subunit vaccines were confirmed. The data suggest that CSFV E2-Fc recombinant fusion protein may be a promising candidate subunit vaccine to elicit immune response and protect against CSFV.

Comparison of gE/gI- and TK/gE/gI-Gene-Deleted Pseudorabies Virus Vaccines Mediated by CRISPR/Cas9 and Cre/Lox Systems.

Pseudorabies (PR), caused by pseudorabies virus (PRV), is an acute and febrile infectious disease in swine. To eradicate PR, a more efficacious vaccine needs to be developed. Here, the gE/gI- and TK/gE/gI-gene-deleted recombinant PRV (rGXΔgE/gI and rGXΔTK/gE/gI) are constructed through CRISPR/Cas9 and Cre/Lox systems. We found that the rGXΔTK/gE/gI was safer than rGXΔgE/gI in mice. Additionally, the effects of rGXΔgE/gI and rGXΔTK/gE/gI were further evaluated in swine. The rGXΔgE/gI and rGXΔTK/gE/gI significantly increased numbers of IFN-γ-producing CD4+ and CD8+ T-cells in swine, whereas there was no difference between rGXΔgE/gI and rGXΔTK/gE/gI. Moreover, rGXΔgE/gI and rGXΔTK/gE/gI promoted a PRV-specific humoral immune response. The PRV-specific humoral immune response induced by rGXΔgE/gI was consistent with that caused by rGXΔTK/gE/gI. After the challenge, swine vaccinated with rGXΔgE/gI and rGXΔTK/gE/gI showed no clinical signs and viral shedding. However, histopathological detection revealed that rGXΔgE/gI, not rGXΔTK/gE/gI, caused pathological lesions in brain and lung tissues. In summary, these results demonstrate that the TK/gE/gI-gene-deleted recombinant PRV was safer compared with rGXΔgE/gI in swine. The data imply that the TK/gE/gI-gene-deleted recombinant PRV may be a more efficacious vaccine candidate for the prevention of PR.

Development of a Novel Six-miRNA-Based Model to Predict Overall Survival Among Colon Adenocarcinoma Patients.

Introduction: Colon carcinoma is a common malignant tumor worldwide. Accurately predicting prognosis of colon adenocarcinoma (CA) patients may facilitate clinical individual decision-making. Many studies have reported that microRNAs (miRNAs) were associated with prognosis for patients with colon carcinoma. This study aimed to identify the prognosis-related miRNAs for predicting the overall survival (OS) of CA patients. Methods: Firstly, we analyzed the CA datasets from the Cancer Genome Atlas (TCGA), and looked for the prognosis-related miRNAs. Then, we developed a novel prediction model based on these miRNAs and the clinical characteristics. Time-dependent receiver operating characteristics (ROC) curves and calibration plots were used to evaluate the discrimination and accuracy of the signature and model. Finally, cell function assays and bioinformatics analyses were performed to evaluate the role of these selected miRNAs in modulating biological process in CA. Results: Six prognosis-related miRNAs were included in the miRNA-based signature, and it could effectively distinguish low-risk patients and high-risk patients. Furthermore, we established a prognostic model incorporating the six-miRNA-based signature and clinical characteristics. Areas under curves (AUCs) indicated that the six-miRNA-based model has a better predictive ability than TNM stage (AUC: 0.805 vs. 0.694). The calibration plots suggested close agreement between model predictions and actual observations. GO analysis showed that the target genes of these miRNAs are mainly involved in enrichment in protein binding and regulation of transcript and cytosol. KEGG pathway enrichment analysis indicated that these genes were mainly enriched in PI3K-Akt signaling pathway. Finally, we found that the five miRNAs except miR-152 were upregulated in tumor tissues and CA cells. The functional experiments revealed that miR-1245a, miR-3682, miR-33b, and miR-5683 promoted the migratory abilities and proliferation of CA cell, whereas miR-152 showed opposite effects. However, miR-4444-2 did not influence the migratory ability and proliferation of CA cell. Conclusions: In conclusion, we developed a novel six-miRNA-based model to predict 5-year survival probabilities for CA patients. This model has the potential to facilitate individualized treatment decisions.

[Application of domestically made endoscopic stapling instrument for laparoscopic assisted rectal cancer resection].

OBJECTIVE: To investigate the safety and feasibility of domestically made endoscopic stapling instrument in laparoscopic assisted rectal cancer resection (Dixon). METHODS: Sixty-four patients with rectal cancer were randomly divided into the research group (35 cases) to receive laparoscopic assisted rectal cancer resection using ENDO RLC general endoscopic linear cutter and single-use loading unit and circular staplers with staples (from REACH medical equipment co.LTD) and the control group (29 cases) to receive surgery with the corresponding products widely used (fom Johnson and Johnson Medical Euipment C.Ltd). The clinical data of the two groups were compared. RESULTS: Satisfactory therapeutic effects were obtained in all the cases. The two groups showed no significant differences in the operative time, intraoperative anastomosis success rate, or postoperative complications (anastomotic bleeding, leakage, or stricture) between the two groups (P>0.05), but the average cost of endoscopic stapling instrument was significantly lower in the research group (6604.31 ± 699.95 vs 7822.28 ± 576.98 RMB Yuan, P<0.05). CONCLUSION: The domestic endoscopic stapling instrument is safe, effective and less costly for laparoscopic assisted rectal cancer resection.

[Effect of different approaches to transplanting bone marrow stromal stem cells into the allogenic rat liver].

OBJECTIVE: To compare the effect of different approaches of bone marrow stromal stem cell (BMSCs) transplantation into the allogenic rat liver. METHODS: Thirty male SD rats were randomized equally into local liver group, portal vein group, and femoral vein group, and received injection of 1×106/ml BMSCs directly into the rat liver, through the portal vein and through the femoral vein, respectively. The rat livers were scanned by magnetic resonance imaging (MRI) at 12 h and 1, 3, 5, 7, 14 days after the cell transplantation. Prussian blue staining of the rat liver sections was also performed 14 days after the transplantation. RESULTS: MRI showed decreased signal intensity in all the rat livers of the local liver group; the ovoid area of the signal intensity gradually shrunk and the signal intensity increased with the passage of time. Lowered signal intensity was also seen in the rat livers of the portal vein group, appearing constantly branch-shaped, indistinct and increased gradually. Decreased signal intensity did not occur in the livers of femoral vein group. Prussian blue staining of all the rat livers at day 14 showed the presence of cells containing blue particles in all the groups, most numerous in the local liver group followed by the portal vein group and then the femoral vein group. CONCLUSION: Direct intrahepatic injection of the BMSCs results in better effect than cell transplantation via the portal vein or the femoral vein.

[Laparoscopic anterior resection of rectal carcinoma with preservation of the left colonic artery].

OBJECTIVE: To evaluate the feasibility and efficacy of laparoscopic anterior resection of rectal carcinoma with preservation of the left colonic artery. METHODS: From February 2006 to February 2009, 52 patients with rectal carcinoma formerly scheduled for Dixon operation (clinical stage I and II) received laparoscopic Dixon surgery. The inferior mesenteric artery, left colonic artery, sigmoid artery or superior rectal artery, and lymph nodes were dissected through the vasa vasorum approach. The left colonic artery was retained by transecting the inferior mesenteric artery inferior to the left colonic artery. The operative time, intraoperative hemorrhage volume, intraoperative complications, anastomotic tension, number and histopathological features of the dissected lymph nodes surrounding the inferior mesenteric artery, and the rates of local recurrence, lymph node metastasis and anastomotic leakage were analyzed. RESULTS: The operation was successfully completed in all the 52 cases. The operative time ranged from 115 to 320 min with a mean of 150 min. The mean intraoperative hemorrhage was 25 ml (range 15-75 ml). None of the patients had perforation of the rectum, injuries to blood vessel, ureter or adjacent organs, or anastomotic tension. The number of dissected lymph nodes surrounding the inferior mesenteric artery ranged from 4 to 8, with a mean of 6.2. The dissected lymph nodes in the base of the inferior mesenteric artery showed no cancer cell metastasis, while 4 patients had cancer cell metastasis in the lymph nodes surrounding superior rectal artery. None of patients had anastomotic leakage. Local recurrence was found in only 1 case at 7 months after the operation. CONCLUSION: Laparoscopic anterior resection of the rectal carcinoma with preservation of the left colonic artery can be completed in patients with rectal carcinoma planning to receive Dixon operation (clinical stage I or II). This surgical approach preserves more supplying vessels and prevents anastomotic leakage without increasing the anastomotic tension or affecting lymph node dissection surrounding the inferior mesenteric artery.

[Effects of specific small interfering RNA on Smoothened expression and LoVo cell proliferation and apoptosis].

OBJECTIVE: To study the effects of specific small interfering RNA (siRNA) on Smoothened (Smo) gene expression and the proliferation and apoptosis of colorectal cancer LoVo cells. METHODS: Three different siRNAs (siRNA-1, siRNA-2, and siRNA-3, respectively) were transfected into LoVo cells via cationic liposome, and the changes of Smo mRNA level were determined using semi-quantitative RT-PCR 48 h after transfection. Flow cytometry and MTT assay were performed to assess the effect of the siRNAs on the proliferation and apoptosis of LoVo cells. RESULTS: Forty-eight hours after Smo siRNA-1 transfection, Smo mRNA expression in LoVo cells decreased by about 63.56%, a reduction significantly greater than that in cells transfected with the other two siRNAs. The cell proliferation decreased significantly after Smo siRNA-1 transfection in comparison with the control cells, and 48 h after transfection, significantly higher apoptosis rate was observed in Smo siRNA-1-transfected cells than in the control cells. CONCLUSION: Specific siRNA can significantly decrease Smo mRNA expression and inhibit the proliferation while inducing apoptosis of LoVo cells.

[Histological observations of chemically induced acute hepatic injury repaired by allogeneic bone marrow stem cell transplantation].

OBJECTIVE: To explore the possibility of repairing chemically induced acute hepatic injuries with allogeneic bone marrow stem cell (BMSC) transplantation. METHODS: A SD rat model of CCl(4)-induced acute hepatic injury was established, which received transplantation of BMSCs (2.0 ml, 1x10(6)/ml) or normal saline injection into the local liver parenchyma, respectively. The rats were sacrificed at 6 h before and 6 h, 1, and 5 weeks after transplantation, and the livers were prepared for microscopic examination. RESULTS: Cellular necrosis, bridging necrosis, congestion in the hepatic sinusoid, and inflammatory cell infiltration were seen in the chemically injured livers 6 h after model establishment, and these changes were ameliorated in rats receiving BMSC transplantation. CONCLUSIONS: Allogeneic BMSC transplantation can repair chemically induced acute liver injuries.

[Expression of Smo protein and the downstream transcription factor Gli1 protein in Sonic hedgehog signal transduction pathway in gastric carcinoma].

OBJECTIVE: To study the expression of Smo protein and the downstream transcription factor Gli1 protein in Sonic hedgehog signal transduction pathway in gastric carcinoma. METHODS: A tissue microarray was constructed using 85 gastric carcinoma and 25 normal gastric mucosa specimens. The expression of Smo and Gli1 proteins were detected immunohistochemically and the correlation between their expression in gastric carcinoma was analyzed. RESULTS: Only weak expression, if any, of Smo and Gli1 proteins was detected in normal gastric mucosa, but in papillary adenocarcinoma, tubular adenocarcinoma and poorly differentiated adenocarcinoma, their expressions were significant increased as the differentiation degree was lowered. Smo protein expression in gastric carcinoma was significantly correlated with that of Gli1 protein with correlation coefficient of 0.989 (P<0.001). CONCLUSION: The abnormal activity of Sonic hedgehog signal transduction pathway may play an important role in the occurrence of papillary adenocarcinoma, tubular adenocarcinoma and poorly differentiated adenocarcinoma, and this abnormality is associated with Smo protein overexpression, which upregulates the expression of the downstream transcription factor Gli1 protein.