Inflammatory bowel disease (IBD) is an autoimmune disorder involving complex immune regulation, where balancing localized and systemic immunosuppression is a key challenge. This study aimed to enhance the therapeutic efficacy by engineering the probiotic Escherichia coli Nissle 1917 (EcN). We removed endogenous plasmids pMUT1 and pMUT2 from wild-type EcN and expressed the mPD-L1 (19‒238 aa)-mFc fusion protein on the bacterial surface using a cytolysin A (ClyA) fragment. This modification stabilized mPD-L1 (19‒238 aa) protein expression and promoted its recruitment to outer membrane vesicles (OMVs). The engineered strain, EcNΔ_pMUT1/2-ClyA-mPD-L1-mFc (EcN-ePD-L1-mFc), features conditional ePD-L1-mFc expression under the araBAD promoter, enhancing gut-targeted release and reducing systemic side effects. This strain improved treatment targeting and efficiency by enabling direct ePD-L1-mFc interaction with immune cells at inflammation sites. OMVs from this strain induced Treg proliferation, inhibited effector T cell proliferation in vitro, and significantly improved intestinal inflammation and colonic epithelial barrier repair in vivo. Additionally, the bacterium restored intestinal microbiota balance, increasing Lactobacillaceae and reducing Bacteroides. This study highlights the engineered bacterium's potential for targeted intestinal immune modulation and offers a novel local IBD treatment approach with promising clinical prospects.

Objective: To establish a new scoring system based on the clinicopathological features of hepatocellular carcinoma (HCC) to predict prognosis of patients who received hepatectomy. Methods: A total of 845 HCC patients who underwent hepatectomy from 1999 to 2010 at Cancer Hospital, Chinese Academy of Medical Sciences were retrospectively analyzed. 21 common clinical factors were selected in this analysis. Among these factors, the cut-off values of alpha-fetoprotein (AFP), alkaline phosphatase (ALP) and intraoperative blood loss were evaluated by using a receiver operating characteristic (ROC) curve analysis.The Kaplan-Meier method and Cox regression model were used to evaluate the independent risk factors associated with the prognosis of HCC patients after hepatectomy. HCC postoperatively prognostic scoring system was established according to the minimum weighted method of these independent risk factors, and divided the patients into 3 risk groups, including low-risk, intermediate-risk and high-risk group. The relapse-free survival (RFS) and overall survival (OS) were compared among these groups. Results: The univariate analysis showed that clinical symptoms, preoperative α-fetoprotein (AFP) level, serum alkaline phosphatase (ALP) level, tumor size, tumor number, abdominal lymph node metastasis, macrovascular invasion or tumor thrombus, extrahepatic invasion or serosa perforation, the severity of hepatic cirrhosis, intraoperative blood loss, the liver operative method, pathological tumor thrombus, intraoperative blood transfusion, perioperative blood transfusion were significantly associated with median RFS of these HCC patients (P<0.05). Alternatively, clinical symptoms, preoperative AFP level, serum ALP level, tumor size, tumor number, abdominal lymph node metastasis, macrovascular invasion or tumor thrombus, extrahepatic invasion or serosa perforation, the severity of hepatic cirrhosis, intraoperative blood loss, the liver operative method, pathological lymphocyte invasion, pathological tumor thrombus, intraoperative blood transfusion, perioperative blood transfusion were significantly associated with the median OS of these HCC patients (P<0.05). The multivariate analysis showed that AFP ≥20 ng/ml, clinical symptoms, tumor diameter ≥5 cm, multiple tumors, macrovascular invasion or tumor thrombus, extrahepatic invasion or serosa perforation, moderate and severe liver cirrhosis, non- anatomic resection were the independent risk factors of RFS and OS (P<0.05). The independent risk factor of RFS was intraoperative bleeding loss ≥325 ml (P<0.05); The independent risk factors of OS were abdominal lymph node metastasis and pathological tumors thrombus (P<0.05). The respective weight of 11 independent factors was used to establish the scoring system (scores range from 0 to 26). In the score system, 0 to 5 points were defined as the low-risk group (286 cases), 6 to 12 points were determined as the intermediate-risk group (503 cases), more than 13 points were classified as the high-risk group (56 cases). The median RFS of the low-risk, intermediate-risk and high-risk group were 80, 27 and 6 months, respectively. The differences were statistically significant (P<0.001). The median OS of the three groups were 134, 51 and 15 months, respectively, and the differences were statistically significant (P<0.001). Conclusion This new score system provides effective prediction of postoperative prognosis for HCC patients.

Objective To prepare human vascular endothelial growth factor receptor 2 (VEGFR2)-targeted liquid perfluorocarbons-filled nanocapsules ultrasound contrast agent,and to investigate its ability of targeting human umbilical endothelial vein cells(HUEVC) and the peculiarity of the enhancing ultrasound imaging in vitro.Methods Rotary evaporation/emulsion technique was used to prepare biotinylated liquid perfluorocarbons-filled nanocapsules (LNCs).VEGFR2-tageted LNCs (V2-LNCs) was further made through conjugating the ligand (biotinylated anti-VEGFR2 antibody) to the surface of LNCs by biotin-avidin system and its appearance,distribution,size and zeta-potential properties were assessed.Immunofluorescent staining assay was used to identify the combination of ligand with the nanocapsules.The ability of V2-LNCs targeting with HUEVC in vitro was evaluated under the fluorescence microscope.Quantitative and statistical analysis were performed to evaluate the ultrasound contrast enhancement of the nanocapsules in vitro.Results The V2-LNCs are uniform and stabilized with size about (98.45 ± 0.07)nm.The ligation of antiVEGFR2 antibody and nanocapsules was positive in immunofluorescent straining assay.In vitro,targeting ability research showed the V2-LNCs could actively adhere to HUEVC,while the control was negative.At the same time,using anti-VEGFR2 antibody to pre-incubation with HUVEC could effectively block the interaction between V2-LNCs and HUEVC.The ultrasound images proved both V2-LNCs and LNCs can significantly enhanced ultrasound imaging contrast agent effect at a concentration of 5 mg/ml in vitro.Conclusions A stable VEGFR2-targeted liquid perfluorocarbons-filled nanocapsules was prepared successfully with biotin-avidin method and effectively bound to HUVEC specially in vitro.Also the liquid perfluorocarbons-filled nanocapsules can strongly enhance the ultrasound contrast in vitro,which might be taken as a kind of vascular ultrasound contrast agent and to get the basic experimental data for the later research.

ObjectiveTo assess the effect of transarterial radioembolization (TARE) using Yttrium-90 microsphere for unresectable primary liver cancer (PLC).MethodsLiterature from January 2009 to December 2013 were searched in the Medline, Web of Science, Cochrane Controlled Trial Register (CENTRAL) and EMBASE databases with the search terms mainly including: radioembolization, transarterial radioembolization, TARE, selective internal radiation therapy, SIRT, Yttrium-90, 90Y, chemoembolization, transarterial chemoembolization (TACE), hepatocellular carcinoma, HCC, liver cancer, liver tumor, liver neoplasm and with the assistance of manual searching. Data of the included literature were merged and the patients were divided into TARE group and TACE group according to the different treatments. The data of tumor therapeutic response and 1-, 2-, 3-year survival rates were collected. Literature heterogeneity inspection was conducted byQ test. Publication bias was tested by drawing funnel plot and linear regression model.ResultsFive articles were included after screening with the quality of medium to high. There were totally 591 cases with 292 in TARE group and 299 in TACE group. Meta-analysis was conducted using fixed effect model. Tumor therapeutic response was observed better in TARE group, compared with that in TACE group (RR=1.50,P<0.05). The 2-, 3-year survival rates in TARE group were signiifcantly higher than those in TACE group (RR=1.56, 2.04;P<0.05).ConclusionsCompared with TACE, TARE can obviously improve the tumor therapeutic response rate and long-term survival rate of patients with unresectable PLC.