Objective To explore the effect and preliminary mechanism of the plant-derived immunostimulatory molecule,ophiopogonin,on enhancing the immune response of a subunit vaccine with the receptor-binding domain(RBD)of coronavirus spike protein as the antigen.Methods CCK-8 assay was used to determine the cytotoxicity of ophiopogonin D'(OPD')on bone marrow-derived dendritic cells(BMDCs).Female Balb/c mice were randomly divided into RBD,RBD/OPD',RBD/Alum,and control groups.The immunization dose was 5 μg of antigen per mouse and 100 μg of adjuvant per mouse,and immunization was carried out according to the intramuscular injection immunization procedure on days 0,21,and 42.The titers of specific IgG and its subtype antibodies were detected by ELISA.The cytokine levels in the supernatant of splenocytes were detected using ELISA.The number of splenocytes secreting IFN-γ was detected by ELISpot.Laser confocal microscopy was employed to observe the uptake of antigen by BMDCs.The phagocytic ability of BMDCs for antigen was quantitatively analyzed by flow cytometry.The mechanism of its enhanced immune effect was preliminarily explored using transcriptomics technology combined with bioinformatics research.Results When the concentration of OPD'was less than 5 μg/mL,the survival rate of BMDCs was 100%.After a single intramuscular injection in mice,except for a slight decrease in body weight,the other biochemical indicators were within corresponding normal ranges.After intramuscular injection immunization of the vaccine,the titers of serum-specific IgG,IgG1,and IgG2a in the RBD/OPD'group were significantly higher than those in the RBD group(P<0.05).Compared with the RBD group,the RBD/OPD'group induced a high-level Th1 cell immune response of IL-1β,TNF-α,and IFN-γ(P<0.01)and had more lymphocytes secreting IFN-γ(P<0.001).Laser confocal microscopy displayed that BMDCs took up more antigens after OPD'treatment,which was further confirmed with flow cytometry in quantitative analysis on antigen uptake rate(P<0.01).Transcriptomics results indicated that there was more significant enrichment of the PPAR signaling pathway in the RBD/OPD'group than the RBD group,suggesting that OPD'may activate the PPAR signaling pathway to exert its adjuvant effect.Conclusion OPD'effectively enhances the immune response of the RBD subunit vaccine,and its action mechanism may be related to the activation of the PPAR signaling pathway.

Objective To construct an in vitro co-culture model of gastric cancer organoids and cancer-associated fibroblasts(CAFs),and investigate the role of cancer-associated fibroblasts in the proliferation and chemotherapy resistance of gastric cancer organoids.Methods Tumor tissues from 12 gastric cancer patients undergoing surgical treatment in Department of General Surgery of Second Affiliated Hospital of Army Medical University from February 2023 to March 2024 were collected to construct gastric cancer organoids using 3D culture.HE staining was used to observe the morphology,and immunohistochemical assay was employed to determine the expression of cytokeratin CK7,carcinoembryonic antigen(CEA),and proliferation marker Ki-67.After CAFs derived from the same patient were cultured,observed for their morphology under a light microscope,and detected for the phenotype by flow cytometry,the cells were co-cultured with gastric cancer organoids in a 1:1 ratio.Phase-contrast microscopy was applied to observe the growth of the organoids and analyze the number,average diameter,and total area.Then,organoids cultured alone served as the control group.After the control and co-culture groups were treated with chemotherapy drugs,5-fluorouracil and oxaliplatin,for 48 h,the viability and apoptosis of organoids were assessed with CellTiter-Glo??3D assay and CellEvent? Caspase 3/7 activity,respectively.Results Gastric cancer organoids and CAFs were successfully established from 10 gastric cancer patient-derived samples.The gastric cancer organoids exhibited morphological characteristics consistent with the corresponding primary tumors,and showed positive expression of CK7,CEA,and Ki-67.CAFs displayed typical spindle-shaped morphology and exhibited the phenotypic markers CD326-,CD45-,CD31-,α-SMA+,CD73+,CD90+,and CD105+.Compared to the organoids cultured alone,the organoids co-cultured with CAFs showed more formation of organoids,in larger average diameter,and taking larger total area(P<0.05).After the treatment of 5-fluorouracil and oxaliplatin,the half-maximal inhibitory concentration(IC50)was 10.66 and 3.26 μmol/L,respectively in the control group,while was 46.23 and 91.11 μmol/L in the co-culture group.Additionally,the number of CellEvent? Caspase 3/7 positive apoptotic cells was significantly less in the co-culture group than the control group.Conclusion Compared with individually cultured gastric cancer organoids,the co-culture model of gastric cancer organoids and CAFs better simulates the pro-tumor proliferation and drug resistance effects of in vivo tumor microenvironment.

Objective To establish a mouse model of infection with the minimum lethal dose of Vibrio vulnificus(V.vulnificus)and to evaluate the protective efficacy of inactivated whole-cell(IWC)vaccine using this model.Methods A mouse model of lethal-dose infection was established by intraperitoneal injection of different doses of V.vulnificus.Bacterial colonization in the organs was detected with tissue homogenate plating,and pathological changes in the organs were observed after tissue section staining.Flow cytometry was used to detect immune cell responses after liver tissues were digested into single-cell suspension.IWC vaccine of V.vulnificus was prepared,and the mice were immunized through different routes to observe the protective efficacy of the vaccine.Results A mouse model of infection with the minimum lethal dose at 1×106 CFU of V.vulnificus was successfully established.After infection,the bacteria were mainly colonized in the liver of mice and caused severe pathological damages.Compared with the uninfected mice,the proportion of neutrophils in the liver was significantly increased in the infected mice,whereas the proportions of B cells and T cells were correspondingly decreased(P<0.05).A single intramuscular or intraperitoneal injection of the IWC vaccine could protect the mice effectively against lethal infection of V.vulnificus in 7 d later(P<0.01),although the level of serum IgG having no significant increase.Conclusion A mouse model of lethal-dose infection with V.vulnificus is successfully established,with histopathological characteristics.The IWC vaccine of V.vulnificus rapidly mediates immune protection in this model probably independent of IgG.

Objective To investigate the risk factors of in-hospital mortality and establish a risk prediction model for patients receiving venoarterial extracorporeal membrane oxygenation(VA-ECMO).Methods We retrospectively collected the data of 302 patients receiving VA-ECMO in ICU of 3 hospitals in Guangdong Province between January,2015 and January,2022 using a convenience sampling method.The patients were divided into a derivation cohort(201 cases)and a validation cohort(101 cases).Univariate and multivariate logistic regression analyses were used to analyze the risk factors for in-hospital death of these patients,based on which a risk prediction model was established in the form of a nomogram.The receiver operator characteristic(ROC)curve,calibration curve and clinical decision curve were used to evaluate the discrimination ability,calibration and clinical validity of this model.Results The in-hospital mortality risk prediction model was established based the risk factors including hypertension(OR=3.694,95%CI:1.582-8.621),continuous renal replacement therapy(OR=9.661,95%CI:4.103-22.745),elevated Na2+ level(OR=1.048,95%CI:1.003-1.095)and increased hemoglobin level(OR=0.987,95%CI:0.977-0.998).In the derivation cohort,the area under the ROC curve(AUC)of this model was 0.829(95%CI:0.770-0.889),greater than those of the 4 single factors(all AUC<0.800),APACHE Ⅱ Score(AUC=0.777,95%CI:0.714-0.840)and the SOFA Score(AUC=0.721,95%CI:0.647-0.796).The results of internal validation showed that the AUC of the model was 0.774(95%CI:0.679-0.869),and the goodness of fit test showed a good fitting of this model(χ2=4.629,P>0.05).Conclusion The risk prediction model for in-hospital mortality of patients on VA-ECMO has good differentiation,calibration and clinical effectiveness and outperforms the commonly used disease severity scoring system,and thus can be used for assessing disease severity and prognostic risk level in critically ill patients.

Objective To investigate the distribution of B cells in both tumor and non-tumor tissues of gastric cancer patients,analyze their phenotypic characteristics and explore the impact on T cell proliferation.Methods Immunohistochemical staining was utilized to detect the expression of B cell surface marker CD 19 in tumor and non-tumor tissues from 33 gastric cancer patients.The expression levels of chemokine receptors and immunoglobulin molecules on B cells in both tumor and non-tumor tissues were measured using flow cytometry.Chemotaxis experiments were conducted to examine the role of the CXCL12-CXCR4 axis in B cell chemotaxis.B cells isolated and purified from both tissue types were co-cultured with autologous peripheral T cells to assess their effect on T cell proliferation.Results There were significantly more B cells infiltrated in tumor tissues than those infitrated in the non-tumor tissues of gastric cancer patients(P＜0.01),and CXCR4 was highly expressed on tumor-infiltrating B cells compared with B cells derived from non-tumor tissues(P＜0.05).The Cancer Genome Atlas(TCGA)analysis indicated that the expression level of CXCL12 in tumor tissues was positively correlated with the expression level of CD19 in gastric cancer patients(r=0.15,P＜0.01).And the expression level of CXCL12 in tumor tissues of the gastric cancer patients was also positively correlated with the number of B cells infiltrated in tumor tissues.Chemotaxis experiments confirmed that the CXCL12-CXCR4 axis was involved in promoting B cell chemotaxis(P＜0.05).Although B cells in tumor and non-tumor tissues had similar levels of IgM,IgG,and IgA expression,tumor-infiltrating B cells significantly inhibited the proliferation of T cells when compared with B cells derived from non-tumor tissues(P＜0.01).Conclusion There are more B cells infiltrated in gastric cancer tissues,which may be recruited to tumor tissues through the CXCL12-CXCR4 axis,and then inhibit T cell proliferation to promote the progression of gastric cancer.

Objective To investigate the risk factors of in-hospital mortality and establish a risk prediction model for patients receiving venoarterial extracorporeal membrane oxygenation(VA-ECMO).Methods We retrospectively collected the data of 302 patients receiving VA-ECMO in ICU of 3 hospitals in Guangdong Province between January,2015 and January,2022 using a convenience sampling method.The patients were divided into a derivation cohort(201 cases)and a validation cohort(101 cases).Univariate and multivariate logistic regression analyses were used to analyze the risk factors for in-hospital death of these patients,based on which a risk prediction model was established in the form of a nomogram.The receiver operator characteristic(ROC)curve,calibration curve and clinical decision curve were used to evaluate the discrimination ability,calibration and clinical validity of this model.Results The in-hospital mortality risk prediction model was established based the risk factors including hypertension(OR=3.694,95%CI:1.582-8.621),continuous renal replacement therapy(OR=9.661,95%CI:4.103-22.745),elevated Na2+ level(OR=1.048,95%CI:1.003-1.095)and increased hemoglobin level(OR=0.987,95%CI:0.977-0.998).In the derivation cohort,the area under the ROC curve(AUC)of this model was 0.829(95%CI:0.770-0.889),greater than those of the 4 single factors(all AUC<0.800),APACHE Ⅱ Score(AUC=0.777,95%CI:0.714-0.840)and the SOFA Score(AUC=0.721,95%CI:0.647-0.796).The results of internal validation showed that the AUC of the model was 0.774(95%CI:0.679-0.869),and the goodness of fit test showed a good fitting of this model(χ2=4.629,P>0.05).Conclusion The risk prediction model for in-hospital mortality of patients on VA-ECMO has good differentiation,calibration and clinical effectiveness and outperforms the commonly used disease severity scoring system,and thus can be used for assessing disease severity and prognostic risk level in critically ill patients.

The design and practice of graduation project is not only an important part of teaching plan on pharmaceutical students,but also a good opportunity to train and improve their scientific research ability.In this paper,taking the practical training of graduation project on pharmaceutical students as an example,and combined with the actual teaching work,some experience from the graduation project selection,experiment design,data collection,writing papers and oral defense will be separately discussed about how to train the scientific research ability of pharmaceutical students.Through designing and practicing of the graduation project,the comprehensive quality and scientific research ability of pharmaceutical students have been effectively trained and promoted,which will lay a good foundation for continuing postgraduate research or taking drug research jobs.