The purpose of this study is to investigate the effect of TPCK trypsin on the proliferation pattern of porcine epidemic diarrhea virus in Vero cells.The TPCK trypsin and conventional tryp-sin were added for virus proliferation,and RT-qPCR technology was used to analyze the changes in virus adsorption and invasion in Vero cells.The replication ability of porcine epidemic diarrhea vi-rus in Vero cells was explored through growth curve drawing,IFA identification,and cell activity detection.The results showed that the optimal concentrations of TPCK trypsin and conventional trypsin were 1 mg/L and 6 mg/L,respectively.The virus showed a decreasing trend with the pro-longation of TPCK trypsin and conventional trypsin pretreatment time.Adding different pancreatic enzymes during the virus proliferation process did not promote the virus invasion in Vero cells.Af-ter 4 h of invasion,the virus particles of each group gradually increased.By plotting the growth curve,it was found that the virus content of the TPCK trypsin group reached its highest level at 24 h(lgTCID50=(6.30±0.14)/0.1 mL),followed by a decreasing trend at 36 h,and the fluorescence intensity produced at 24 h was higher than that of conventional trypsin.In summary,TPCK trypsin has a better promoting effect on the proliferation of porcine epidemic diarrhea virus in Vero cells.It provided theoretical basis for further research on the mechanism of TPCK trypsin affecting porcine epidemic diarrhea virus proliferation,and also provided data support for the isola-tion and purification of porcine epidemic diarrhea virus epidemic strains.

Cholera toxin B subunit(CTB)can enhance antigen presentation and promote T cell pro-liferation,B cell differentiation and B cell isotype conversion.Moreover,woodchuck hepatitis virus post transcriptional regulatory element(WPRE)can enhance gene expression efficiency by optimi-zing RNA polyadenylation,denuclearization and/or translation.In order to construct porcine epi-demic diarrhea virus like particles(VLPs)chimerized with CTB and WPRE and evaluate their im-munogenicity,the G Ⅱ type PEDV S gene,combined with the elements promoting the protein ex-pression and enhancing immune effects,was synthesized by the company and cloned into pET32a(+).Af-ter double enzyme digestion and gel recovery,the gene named as TSCW was cloned into pFastBacl to construct the recombinant plasmid pFastBac-TSCW.pFastBac-TSCW was further transformed into DH10Bac competent cells to obtain recombinant bacmid Bacmid-TSCW.Subsequently,the Bacmid-TSCW was transfected into sf9 cells to obtain recombinant baculovirus BV-TSCW.After co-infection of BV-TSCW and BV-M into sf9 cells,viral like particles VLP-TSCW was obtained and used to immunize mice to evaluate its immunogenicity.The results showed that the recombi-nant plasmid pFastBac-TSCW and bacmid Bacmid-TSCW were successfully constructed.After transfection of sf9 cells with recombinant baculovirus,significant cytopathic effects were observed.PCR and Western blot results showed that the recombinant baculoviruses existed stably in sf9 cells and the target proteins was also expressed stably.In addition,the electron microscopy results showed that BV-TSCW and BV-M successfully assembled into viral like particles VLP-TSCW.Furthermore,ELISA results indicated that VLP-TSCW induced high level specific antibodies.The above results laid the foundation for further optimization,design and development of PEDV VLPs subunit vaccines.

Objective:To induce an experimental autoimmune encephalomyelitis(EAE)model by MOG-specific TCR trans-genic mice(2D2TCR transgenic mice),and to investigate effect of exogenous ERMAP on T cells in spleen of MOG35-55-induced 2D2TCR transgenic mice.Methods:EAE models were established in two groups of 2D2TCR transgenic mice(Control-Ig treatment for control group and ERMAP-Ig fusion protein treatment for experimental group),with 9 mice per group.Severity of spinal cord injury of MOG35-55-induced EAE in mice was assessed based on daily clinical scores(DAI),HE and LFB staining results;autoreactive T cells(CD4+Vα3.2+Vβ11+),T cell proliferation activation indicators CD69(CD4+Vα3.2+Vβ11+CD69+)and Ki67(CD4+Vα3.2+Vβ11+Ki67+),Treg(CD4+Vα3.2+Vβ11+CD25+Foxp3+)and Th17 cells(CD4+Vα3.2+Vβ11+IL-17A+)in spleen were detected by flow cytome-try;IL-17A,IL-6,IFN-γ and TGF-β expressions in spinal cord tissues were detected by qRT-PCR.Results:In MOG35-55-induced 2D2TCR transgenic mouse EAE model,ERMAP-Ig fusion protein treatment group showed milder inflammatory infiltration and demye-lination in spinal cord,decreased proportion of autoreactive T cells,decreased proportion of activated and proliferating T cells,increased proportion of Treg,inhibition of Th17 cell differentiation,less inflammatory cell aggregation and cytokine production,and increased expression of anti-inflammatory factors in spinal cord.Conclusion:ERMAP may be involved in development of EAE in 2D2TCR transgenic mice by inhibiting T cell proliferative activation and promoting Treg cell production.

Cholera toxin B subunit(CTB)can enhance antigen presentation and promote T cell pro-liferation,B cell differentiation and B cell isotype conversion.Moreover,woodchuck hepatitis virus post transcriptional regulatory element(WPRE)can enhance gene expression efficiency by optimi-zing RNA polyadenylation,denuclearization and/or translation.In order to construct porcine epi-demic diarrhea virus like particles(VLPs)chimerized with CTB and WPRE and evaluate their im-munogenicity,the G Ⅱ type PEDV S gene,combined with the elements promoting the protein ex-pression and enhancing immune effects,was synthesized by the company and cloned into pET32a(+).Af-ter double enzyme digestion and gel recovery,the gene named as TSCW was cloned into pFastBacl to construct the recombinant plasmid pFastBac-TSCW.pFastBac-TSCW was further transformed into DH10Bac competent cells to obtain recombinant bacmid Bacmid-TSCW.Subsequently,the Bacmid-TSCW was transfected into sf9 cells to obtain recombinant baculovirus BV-TSCW.After co-infection of BV-TSCW and BV-M into sf9 cells,viral like particles VLP-TSCW was obtained and used to immunize mice to evaluate its immunogenicity.The results showed that the recombi-nant plasmid pFastBac-TSCW and bacmid Bacmid-TSCW were successfully constructed.After transfection of sf9 cells with recombinant baculovirus,significant cytopathic effects were observed.PCR and Western blot results showed that the recombinant baculoviruses existed stably in sf9 cells and the target proteins was also expressed stably.In addition,the electron microscopy results showed that BV-TSCW and BV-M successfully assembled into viral like particles VLP-TSCW.Furthermore,ELISA results indicated that VLP-TSCW induced high level specific antibodies.The above results laid the foundation for further optimization,design and development of PEDV VLPs subunit vaccines.

Objective:To induce an experimental autoimmune encephalomyelitis(EAE)model by MOG-specific TCR trans-genic mice(2D2TCR transgenic mice),and to investigate effect of exogenous ERMAP on T cells in spleen of MOG35-55-induced 2D2TCR transgenic mice.Methods:EAE models were established in two groups of 2D2TCR transgenic mice(Control-Ig treatment for control group and ERMAP-Ig fusion protein treatment for experimental group),with 9 mice per group.Severity of spinal cord injury of MOG35-55-induced EAE in mice was assessed based on daily clinical scores(DAI),HE and LFB staining results;autoreactive T cells(CD4+Vα3.2+Vβ11+),T cell proliferation activation indicators CD69(CD4+Vα3.2+Vβ11+CD69+)and Ki67(CD4+Vα3.2+Vβ11+Ki67+),Treg(CD4+Vα3.2+Vβ11+CD25+Foxp3+)and Th17 cells(CD4+Vα3.2+Vβ11+IL-17A+)in spleen were detected by flow cytome-try;IL-17A,IL-6,IFN-γ and TGF-β expressions in spinal cord tissues were detected by qRT-PCR.Results:In MOG35-55-induced 2D2TCR transgenic mouse EAE model,ERMAP-Ig fusion protein treatment group showed milder inflammatory infiltration and demye-lination in spinal cord,decreased proportion of autoreactive T cells,decreased proportion of activated and proliferating T cells,increased proportion of Treg,inhibition of Th17 cell differentiation,less inflammatory cell aggregation and cytokine production,and increased expression of anti-inflammatory factors in spinal cord.Conclusion:ERMAP may be involved in development of EAE in 2D2TCR transgenic mice by inhibiting T cell proliferative activation and promoting Treg cell production.

The purpose of this study is to investigate the effect of TPCK trypsin on the proliferation pattern of porcine epidemic diarrhea virus in Vero cells.The TPCK trypsin and conventional tryp-sin were added for virus proliferation,and RT-qPCR technology was used to analyze the changes in virus adsorption and invasion in Vero cells.The replication ability of porcine epidemic diarrhea vi-rus in Vero cells was explored through growth curve drawing,IFA identification,and cell activity detection.The results showed that the optimal concentrations of TPCK trypsin and conventional trypsin were 1 mg/L and 6 mg/L,respectively.The virus showed a decreasing trend with the pro-longation of TPCK trypsin and conventional trypsin pretreatment time.Adding different pancreatic enzymes during the virus proliferation process did not promote the virus invasion in Vero cells.Af-ter 4 h of invasion,the virus particles of each group gradually increased.By plotting the growth curve,it was found that the virus content of the TPCK trypsin group reached its highest level at 24 h(lgTCID50=(6.30±0.14)/0.1 mL),followed by a decreasing trend at 36 h,and the fluorescence intensity produced at 24 h was higher than that of conventional trypsin.In summary,TPCK trypsin has a better promoting effect on the proliferation of porcine epidemic diarrhea virus in Vero cells.It provided theoretical basis for further research on the mechanism of TPCK trypsin affecting porcine epidemic diarrhea virus proliferation,and also provided data support for the isola-tion and purification of porcine epidemic diarrhea virus epidemic strains.

BACKGROUND:Autoimmune regulator gene(Aire)and Wnt signaling pathway play an important role in the maintenance and differentiation of mouse embryonic stem cell pluripotency.However,whether the Wnt signal and Aire are involved in the differentiation of embryonic stem cells to thymic epithelial progenitor cells remains poorly understood. OBJECTIVE:To investigate the relationship of the Wnt signaling pathway and Aire with the differentiation of embryonic stem cells. METHODS:A two-step differentiation method was used to induce mouse embryonic stem cells to differentiate into endoderm and then into thymic epithelial progenitor cells.Mouse embryonic stem cells were infected with Aire shRNA lentivirus,and monoclonal stable strains were screened by puromycin.Mouse embryonic stem cells were collected on days 0,3 and 10 of the directed induction of differentiation after the induced differentiation by the two-step differentiation method.Cellular immunofluorescence,flow cytometry,western blot assay,and real-time qPCR were used to detect the expression changes of related genes and proteins. RESULTS AND CONCLUSION:(1)Immunofluorescence staining showed positive expression of SSEA1 and OCT4 on day 0 of targeted induction of differentiation.(2)Immunofluorescence staining showed double-positive expression of SOX17 and FOXA2 on day 3 of targeted induction of differentiation.(3)Flow cytometry results showed positive expression of EPCAM1,K5 and K8 on day 10 of targeted induction of differentiation.(4)Compared with undifferentiated mouse embryonic stem cells,the expressions of Wnt7a,β-catenin,and Gsk-3β proteins were elevated,and the expression level of Aire protein was decreased in induced differentiated thymic epithelial progenitor cells.(5)Compared with undifferentiated mouse embryonic stem cells,the expressions of Wnt7a,β-catenin,Gsk-3β and Aire mRNA were elevated in thymic epithelial progenitor cells.(6)Compared with normal cultured mouse embryonic stem cells and their ultimately differentiated thymic epithelial progenitor cells,the expression levels of Wnt7a,β-catenin and Gsk-3β proteins were reduced in mouse embryonic stem cells with knockdown of Aire genes and their final differentiated thymic epithelial progenitor cells.In conclusion,the Wnt signaling pathway and Aire are jointly involved in the process of targeted induction of differentiation of mouse embryonic stem cells into mouse thymic epithelial progenitor cells.

BACKGROUND:The occurrence and development of various ophthalmic diseases are closely related to excessive oxidative stress,and the inhibition of oxidative stress response may produce preventive and therapeutic effects. OBJECTIVE:To explore the role of Pax6 gene expression on hydrogen peroxide-induced aging of mouse bone marrow mesenchymal stem cells(BM-MSCs). METHODS:Resuscitated BM-MSCs,Pax6/BM-MSCs,and shPax6/BM-MSCs were treated with hydrogen peroxide for 24 hours,and then β-galactosidase staining was performed.The proliferation index Ki67 expression and apoptosis were detected by flow cytometry.The expression of senescence-associated molecules(Wnt7a,p21,and p53)was detected by RT-PCR. RESULTS AND CONCLUSION:(1)After hydrogen peroxide treatment,the cells of the three groups showed senescence phenotype and β-galactosidase staining was positive.Compared with BM-MSCs group,the expression of positive cells in Pax6/BM-MSCs group was less and that in the shPax6/BM-MSCs group was more,and the difference was statistically significant(P<0.05).(2)The results of flow cytometry showed that compared with BM-MSCs group,the positive expression of Ki67 in the Pax6/BM-MSCs group increased and the level of apoptosis decreased,while the positive expression of Ki67 decreased and the level of apoptosis increased in the shPax6/BM-MSCs group;the difference was significantly different(P<0.05).(3)RT-PCR showed that compared with the BM-MSCs group,the expression of Wnt7a,p53,and p21 decreased in the Pax6/BM-MSCs group,while the expression of Wnt7a,p53,and p21 increased in the shPax6/BM-MSCs group;the difference was significantly different(P<0.05).(4)These findings indicate that overexpression of Pax6 can antagonize the aging progression of BM-MSCs induced by hydrogen peroxide,which may be related to Wnt signaling pathway.

BACKGROUND/OBJECTIVES: Soy isoflavone (SIF) and soy lecithin (SL) have beneficial effects on many chronic diseases, including neurodegenerative diseases. Regretfully, there is little evidence to show the combined effects of these soy extractives on the impairment of cognition and abnormal cerebral blood flow (CBF). This study examined the optimal combination dose of SIF + SL to provide evidence for improving CBF and protecting cerebrovascular endothelial cells.MATERIALS/METHODS: In vivo study, SIF50 + SL40, SIF50 + SL80 and SIF50 + SL160 groups were obtained. Morris water maze, laser speckle contrast imaging (LSCI), and hematoxylineosin staining were used to detect learning and memory impairment, CBF, and damage to the cerebrovascular tissue in rat. The 8-hydroxy-2′-deoxyguanosine (8-OHdG) and the oxidized glutathione (GSSG) were detected. The anti-oxidative damage index of superoxide dismutase (SOD) and glutathione (GSH) in the serum of an animal model was also tested. In vitro study, an immortalized mouse brain endothelial cell line (bEND.3 cells) was used to confirm the cerebrovascular endothelial cell protection of SIF + SL. In this study, 50 μM of Gen were used, while the 25, 50, or 100 μM of SL for different incubation times were selected first. The intracellular levels of 8-OHdG, SOD, GSH, and GSSG were also detected in the cells. RESULTS: In vivo study, SIF + SL could increase the target crossing times significantly and shorten the total swimming distance of rats. The CBF in the rats of the SIF50 + SL40 group and SIF50 + SL160 group was enhanced. Pathological changes, such as attenuation of the endothelium in cerebral vessels were much less in the SIF50 + SL40 group and SIF50 + SL160 group. The 8-OHdG was reduced in the SIF50 + SL40 group. The GSSG showed a significant decrease in all SIF + SL pretreatment groups, but the GSH showed an opposite result. SOD was upregulated by SIF + SL pretreatment. Different combinations of Genistein (Gen)+SL, the secondary proof of health benefits found in vivo study, showed they have effective antioxidation and less side reaction on protecting cerebrovascular endothelial cell. SIF50 + SL40 in rats experiment and Gen50 + SL25 in cell test were the optimum joint doses on alleviating cognitive impairment and regulating CBF through protecting cerebrovascular tissue by its antioxidant activity. CONCLUSIONS SIF+SL could significantly prevent cognitive defect induced by β-Amyloid through regulating CBF. This kind of effect might be attributed to its antioxidant activity on protecting cerebral vessels.

Objective:To investigate the impact of nutrition supplementation (whey protein, fish oil and vitamin D) and physical exercise (resistance and aerobic exercise) on muscle mass and body fat metrics among community elderly with sarcopenia.Method:102 eligible sarcopenic participants per inclusion and exclusion criteria were randomized into the control group (routine consultation, n=34) or the groups receiving nutrition supplementation (Nutr, n=34) or nutrition supplementation combined with exercise (Nutr+Ex, n=34) for 12 weeks. Muscle and body fat related indicators were compared across groups pre- and post-intervention. Results:Analysis of covariance showed that all indicators were significantly different between groups (all P<0.05). Further pairwise comparisons showed that compared with controls, patients in Nutr group showed increased appendicular muscle mass (ASM) by 0.837 kg ( P=0.003, 95% CI: 0.301 to 1.372) and decreased fat mass by 2.876 kg ( P<0.01, 95% CI: -3.941 to -1.812), while patients in Nutr+Ex group showed increased ASM by 0.745 kg ( P=0.010, 95% CI: 0.180 to 1.311) and decreased fat mass by 2.928kg ( P<0.01, 95% CI: -4.408 to -1.808). Other muscle-related indicators also increased while fat-related indicators decreased in both Nutr and Nutr+Ex groups. However, there is no significant difference between Nutr and Nutr+Ex groups. Conclusions:Nutrition supplementation and physical exercise contribute to muscle mass and body fat improvement among sarcopenic elderly. Lifestyle intervention based on nutrition intervention is important for the community elderly with sarcopenia.