Background Post-weaned piglets suffer from F18+Escherichia coli(E.coli)infections resulting in post-weaning diar-rhoea or oedema disease.Frequently used management strategies,including colistin and zinc oxide,have con...Background Post-weaned piglets suffer from F18+Escherichia coli(E.coli)infections resulting in post-weaning diar-rhoea or oedema disease.Frequently used management strategies,including colistin and zinc oxide,have contrib-uted to the emergence and spread of antimicrobial resistance.Novel antimicrobials capable of directly interacting with pathogens and modulating the host immune responses are being investigated.Lactoferrin has shown promising results against porcine enterotoxigenic E.coli strains,both in vitro and in vivo.Results We investigated the influence of bovine lactoferrin(bLF)on the microbiome of healthy and infected weaned piglets.Additionally,we assessed whether bLF influenced the immune responses upon Shiga toxin-producing E.coli(STEC)infection.Therefore,2 in vivo trials were conducted:a microbiome trial and a challenge infection trial,using an F18+STEC strain.BLF did not affect theα-andβ-diversity.However,bLF groups showed a higher relative abundance(RA)for the Actinobacteria phylum and the Bifidobacterium genus in the ileal mucosa.When analysing the immune response upon infection,the STEC group exhibited a significant increase in F18-specific IgG serum levels,whereas this response was absent in the bLF group.Conclusion Taken together,the oral administration of bLF did not have a notable impact on theα-andβ-diversity of the gut microbiome in weaned piglets.Nevertheless,it did increase the RA of the Actinobacteria phylum and Bifi-dobacterium genus,which have previously been shown to play an important role in maintaining gut homeostasis.Furthermore,bLF administration during STEC infection resulted in the absence of F18-specific serum IgG responses.展开更多
Background Our previous study has reported that supplementation of oligosaccharide-based polymer enhances gut health and disease resistance of pigs infected with enterotoxigenic E.coli(ETEC)F18 in a manner similar to ...Background Our previous study has reported that supplementation of oligosaccharide-based polymer enhances gut health and disease resistance of pigs infected with enterotoxigenic E.coli(ETEC)F18 in a manner similar to carbadox.The objective of this study was to investigate the impacts of oligosaccharide-based polymer or antibiotic on the host metabolic profiles and colon microbiota of weaned pigs experimentally infected with ETEC F18.Results Multivariate analysis highlighted the differences in the metabolic profiles of serum and colon digesta which were predominantly found between pigs supplemented with oligosaccharide-based polymer and antibiotic.The relative abundance of metabolic markers of immune responses and nutrient metabolisms,such as amino acids and carbohydrates,were significantly differentiated between the oligosaccharide-based polymer and antibiotic groups(q<0.2 and fold change>2.0).In addition,pigs in antibiotic had a reduced(P<0.05)relative abundance of Lachnospiraceae and Lactobacillaceae,whereas had greater(P<0.05)Clostridiaceae and Streptococcaceae in the colon digesta on d 11 post-inoculation(PI)compared with d 5 PI.Conclusions The impact of oligosaccharide-based polymer on the metabolic and microbial profiles of pigs is not fully understood,and further exploration is needed.However,current research suggest that various mechanisms are involved in the enhanced disease resistance and performance in ETEC-challenged pigs by supplementing this polymer.展开更多
This study was designed to find the susceptibility of Nitrofurantoin and Fosfomycin among urinary isolates of Escherichia.coli.Four hundred(400)urine samples were collected for susceptibility of nitrofurantoin and fos...This study was designed to find the susceptibility of Nitrofurantoin and Fosfomycin among urinary isolates of Escherichia.coli.Four hundred(400)urine samples were collected for susceptibility of nitrofurantoin and fosfomycin among urinary isolates of E.coli.All indoor and outdoor patients'urinary samples yielded growth of E.coli.Mid-stream urine specimens were inoculated on blood agar and CLED agar and incubated at 35±2°C.Growth was observed,and Escherichia coli was identified by Gram staining,Catalase,Motility test and API 20E(Bio murex)as per standard procedure.Antimicrobial susceptibility testing of isolates for nitrofurantoin and fosfomycin was carried out by the modified Kirby-Bauer disc diffusion method according to CLSI guidelines ATCC 25922.E.coli was used as a quality control strain.A total of 400 samples were tested susceptibility of nitrofurantoin and fosfomycin among urinary isolates of E.coli during this period.A total of 400 samples yielded the growth of E.coli,out of which 178(44.5%)were male and 222(55.5%)were female samples.Among males,18(10%)were tolerant to nitrofurantoin,and 2(1.1%)were tolerant to fosfomycin.Among females,9(4.09%)were susceptible to nitrofurantoin while 6(2.72%)were susceptible to fosfomycin.Among age groups below 45 years old,6(4.76%)were tolerant to nitrofurantoin,and 2(1.58%)were sensitive to fosfomycin.Between 46-66 years old,4(2.81%)were sensitive to nitrofurantoin,and 3(2.11%)were sensitive to fosfomycin.Between 67-90 years old,17(12.87%)were sensitive to nitrofurantoin,and 4(3.03%)were tolerant to fosfomycin.Fosfomycin and nitrofurantoin showed good susceptibility in urinary isolates of E.coli and can be used empirically in our setup.展开更多
Calmodulin (CaM), widely distributed in almost all eukaryotic cells, is a major intracellular calcium receptor responsible for mediating the Ca2 + signal to a multitude of different enzyme systems and is thought to pl...Calmodulin (CaM), widely distributed in almost all eukaryotic cells, is a major intracellular calcium receptor responsible for mediating the Ca2 + signal to a multitude of different enzyme systems and is thought to play a vital role in the regulation of cell proliferative cycle[1,2]. Recently, many studies showed that CaM is also present in extracellular fluid such as cell culture media and normal body fluid and has been reported to stimulate proliferation in a range of normal and neoplastic cells, apparently acting as an autocrine growth factor[3-11]. In 1988, Crocker et al reported for the first time that addition of extracellular pure pig brain CaM could promote DNA synthesis and cell [7]proliferation in K562 human leukaemic lymphocytes[7].After that, more and more research was done on extracellular CaM and evidences demonstrated that extracellular CaM could also stimulate cell proliferation in normal human umbilical vein endothelial cells[5], keratinocytes[4], suspension-cultured cells of Angelica Dahurica, etc[6]. CaM is a monomeric protein of 148 amino acids that contains four homologous Ca2 + -binding domains. CaM has been highly conserved throughout the evolution. Only 1 out of 148 amino acids of human CaM is different from that of fish CaM. Complementary DNAs encoding rat, eel, chicken, human, and trypanosome CaM have been cloned.展开更多
Objective To report a protocol using biotin-labelled PrP protein in cell free conversion assay instead of isotope. Methods A hamster PrP protein (HaPrP) was expressed in E. coli and purified with HIS-tag affinity ch...Objective To report a protocol using biotin-labelled PrP protein in cell free conversion assay instead of isotope. Methods A hamster PrP protein (HaPrP) was expressed in E. coli and purified with HIS-tag affinity chromatograph. After being labelled with biotin, HaPrP was mixed with PrP^sen preparation from scrapie strain 263K. Results Protease-resistant bands were detected after four-day incubation. Conclusion The new conversion model provides a reliable, easily handling, and environment-friendly method for studies of prion and transmissible spongiform encephalopathies.展开更多
Objective: To construct recombinant E.coli LLO/OVA and investigate its tumor metastatic inhibition effect in B16 OVA melanoma challenged mice. Methods: Recombinant E.coli LLO/OVA was constructed and the expression ...Objective: To construct recombinant E.coli LLO/OVA and investigate its tumor metastatic inhibition effect in B16 OVA melanoma challenged mice. Methods: Recombinant E.coli LLO/OVA was constructed and the expression of listeriolysin O (LLO) and ovalbumin (OVA) of the vaccine was determined by coomassie brilliant blue staining and western blotting, After 3 subcutaneous injections of E.coli LLO/OVA, the percentages of CD3^+CD4^+T, CD4^+CD25^+T, CD3^CD8^+T and OVA257-264 SIINFEKL specific CD8^+T cells were determined by flow cytomytry, and the tumor metastatic inhibition effect in B16 OVA melanoma challenged mice was observed. Results: Recombinant E.coli LLO/OVA was successfully constructed, and the expression of LLO and OVA of the vaccine was confirmed. After 3 subcutaneous injections of E.coli LLO/OVA and E.coli OVA in mice, the percentages of CD3^+CD4^+T, CD4^+CD25^+T and CD3^+CD8^+T cells were equivalent in the two groups of mice. However, there were significantly more OVA257-264 SIINFEKL specific CD8^+T cells in E.coli LLO/OVA vaccinated mice than that in E.coli OVA vaccinated mice. The prophylactic E.coli LLO/OVA vaccination effectively prevented the tumor metastasis to lungs in B16 OVA melanoma challenged mice. Depletion of CD8^+T cells significantly impaired the tumor inhibition effect of the vaccine in B16 OVA challenged mice. The therapeutic vaccination of E.coli LLO/OVA significantly prevented melanoma metastasis to lungs in B I6 OVA challenged mice too. Conclusion: Recombinant E.coli LLO/OVA vaccination is highly effective in inhibiting murine malignant melanoma metastasis by promoting CD8^+T cell immunity.展开更多
Objective To explore the immune stimulation effect of recombinant E.coli LLO/OVA on mice bone marrow-derived dendritic cells (BMDCs) and T lymphocytes in vitro.Methods After BMDCs stimulated by E.coli LLO/OVA,their ...Objective To explore the immune stimulation effect of recombinant E.coli LLO/OVA on mice bone marrow-derived dendritic cells (BMDCs) and T lymphocytes in vitro.Methods After BMDCs stimulated by E.coli LLO/OVA,their Toll-like receptor (TLR) and nucleotide-binding oligomerization domain (NOD) receptor signalling pathway were examined by superarray hybridization;and the priming effect of the vaccine activated BMDCs on CD4+T and CD8+T was determined by [3H]thymidine uptake and ELISA,the tumor cytotoxic effect of activated CD8+T cells was determined by cytotoxic assay.Results After BMDCs were activated by E.coli LLO/OVA via TLR4,NOD1 receptor and NF-κB signalling pathway,the expression of their surface molecules including MHC class Ⅰ,MHC class Ⅱ,CD40,CD80 and CD86 significantly up-regulated;the secretion of IL-12 and IFN-? increased also.The mature BMDCs stimulated the allergic CD4+T and CD8+T cells proliferation and their IL-2 and IFN-γ secretion,and the activated CD8+T cells effectively killed B16-OVA melanoma cells and RMA-S/OVA lymphoma cells in vitro.Conclusion E.coli LLO/OVA is effective in inducing BMDCs maturation via activating TLR4 and NOD1 receptor signalling pathway and promoting specific anti-tumor T cell immunity in vitro.展开更多
Objective To explore the role of extracellular vesicles(EVs)in the pathogenesis of glaucoma caused by E50K mutation.Methods A photoreceptor cell line,RGC-5,was transfected with empty plasmids and plasmids expressing w...Objective To explore the role of extracellular vesicles(EVs)in the pathogenesis of glaucoma caused by E50K mutation.Methods A photoreceptor cell line,RGC-5,was transfected with empty plasmids and plasmids expressing wild-type(WT)optineurin(OPTN)or E50K OPTN to investigate the effects of OPTN glaucoma as well as to identify the role of EVs in glaucoma pathology.The RGC-5 cells were also stimulated with glutamate,and their viability was evaluated using flow cytometry or CCK-8 assay.EVs were extracted,labeled with PKH-26,and added into the medium for normal RGC-5 culture,and the status of the cells was observed thereafter.Results WT OPTN overexpression,E50K OPTN,and glutamate stimulation induced apoptosis of RGC-5 cells.However,when glutamate stimulation was used as an add-on treatment,the degree of apoptosis in WT OPTN-overexpressing RGC-5 cells was significantly lower than that in E50K OPTN-expressing and normal RGC-5 cells.The viability of normal RGC-5 cells was reduced when co-cultured with WT OPTN-overexpressing RGC-5 or E50K OPTN-overexpressing RGC-5.EVs released by the latter two transfected lines similarly reduced normal RGC-5 survival.Conclusion Our results indicate that WT OPTN overexpression may lead to photoreceptor apoptosis.However,overexpression also confers a degree of protection against high concentrations of extracellular glutamate.Additionally,EVs released by transfected RGC-5 cells may regulate the cell state.These findings may improve our understanding of the mechanisms of cell-cell interactions in pathological conditions,providing a basis for the use of EVs as novel targets for early diagnosis and treatment of glaucoma.展开更多
The photocatalytic degradation of E.coli membrane cell by ZnO nanowires was studied using field-emission scanning electron microscope(FE-SEM),fluorescence microscopy,and Attenuated total reflection fourier transform...The photocatalytic degradation of E.coli membrane cell by ZnO nanowires was studied using field-emission scanning electron microscope(FE-SEM),fluorescence microscopy,and Attenuated total reflection fourier transform infrared(ATR-FTIR).The outer membrane of E.coli was removed completely in the presence of ZnO nanowires under UV irradiation,and the cells became twisted shapes without a mechanically strong network.After ZnO nanowires photocatalysis,the permeability of the treated cells increased to some degree that could be confirmed by quantum dots labeling technique.Structural changes in the cell wall membrane were revealed by the decay of the characteristic groups bands in ATR-FTIR spectra.展开更多
To explore the role of bcl-2 and bax genes in the apoptosis of human U937 cells induced by E.coli, flow cytometry assay with annexinⅤ-FITC/PI double staining was used to determine the condition of apoptosis, and the ...To explore the role of bcl-2 and bax genes in the apoptosis of human U937 cells induced by E.coli, flow cytometry assay with annexinⅤ-FITC/PI double staining was used to determine the condition of apoptosis, and the expressions of mRNA of bcl-2 and bax genes were assayed with RT-PCR. It was found that the apoptosis of human U937 cells could be induced by E.coli at various concentration ratios between cells and bacteria for 30 min in a dose-dependent manner. The apoptotic rates at cell/bacteria ratios of 0, 1∶5, 1∶10, 1∶20, 1∶50 and 1∶100 were 3.16%±0.90%, 9.46%±0.84%, 17.90%±1.41%, 35.59%±3.76%, 38.35%±7.12% and 55.07%±5.82% respectively. Also, there was a tendency of alterations in the expression levels of bcl-2 and bax genes with an increased expression level of bax gene and a reduced expression level of bcl-2 gene. It is concluded that E.coli can induce apoptosis in human U937 cells with a down-regulated expression of Bcl-2 and an up-regulated expression of Bax, and this might be related to the induction of apoptosis of the infected cell.展开更多
Objective Pseudogenes are initially regarded as nonfunctional genomic sequences,but some pseudogenes regulate tumor initiation and progression by interacting with other genes to modulate their transcriptional activiti...Objective Pseudogenes are initially regarded as nonfunctional genomic sequences,but some pseudogenes regulate tumor initiation and progression by interacting with other genes to modulate their transcriptional activities.Olfactory receptor family 7 subfamily E member 47 pseudogene(OR7E47P)is expressed broadly in lung tissues and has been identified as a positive regulator in the tumor microenvironment(TME)of lung adenocarcinoma(LUAD).This study aimed to elucidate the correlation between OR7E47P and tumor immunity in lung squamous cell carcinoma(LUSC).Methods Clinical and molecular information from The Cancer Genome Atlas(TCGA)LUSC cohort was used to identify OR7E47P-related immune genes(ORIGs)by weighted gene correlation network analysis(WGCNA).Based on the ORIGs,2 OR7E47P clusters were identified using non-negative matrix factorization(NMF)clustering,and the stability of the clustering was tested by an extreme gradient boosting classifier(XGBoost).LASSO-Cox and stepwise regressions were applied to further select prognostic ORIGs and to construct a predictive model(ORPScore)for immunotherapy.The Botling cohorts and 8 immunotherapy cohorts(the Samstein,Braun,Jung,Gide,IMvigor210,Lauss,Van Allen,and Cho cohorts)were included as independent validation cohorts.Results OR7E47P expression was positively correlated with immune cell infiltration and enrichment of immune-related pathways in LUSC.A total of 57 ORIGs were identified to classify the patients into 2 OR7E47P clusters(Cluster 1 and Cluster 2)with distinct immune,mutation,and stromal programs.Compared to Cluster 1,Cluster 2 had more infiltration by immune and stromal cells,lower mutation rates of driver genes,and higher expression of immune-related proteins.The clustering performed well in the internal and 5 external validation cohorts.Based on the 7 ORIGs(HOPX,STX2,WFS,DUSP22,SLFN13,GGCT,and CCSER2),the ORPScore was constructed to predict the prognosis and the treatment response.In addition,the ORPScore was a better prognostic factor and correlated positively with the immunotherapeutic response in cancer patients.The area under the curve values ranged from 0.584 to 0.805 in the 6 independent immunotherapy cohorts.Conclusion Our study suggests a significant correlation between OR7E47P and TME modulation in LUSC.ORIGs can be applied to molecularly stratify patients,and the ORPScore may serve as a biomarker for clinical decision-making regarding individualized prognostication and immunotherapy.展开更多
基金The research that yielded these results,was funded by the Belgian Federal Public Service of Health,Food Chain Safety and Environment through the contract RF 17/6314 LactoPigHealthMatthias Dierick is supported by the Flemish fund for scientific research(FWO3S036319).
文摘Background Post-weaned piglets suffer from F18+Escherichia coli(E.coli)infections resulting in post-weaning diar-rhoea or oedema disease.Frequently used management strategies,including colistin and zinc oxide,have contrib-uted to the emergence and spread of antimicrobial resistance.Novel antimicrobials capable of directly interacting with pathogens and modulating the host immune responses are being investigated.Lactoferrin has shown promising results against porcine enterotoxigenic E.coli strains,both in vitro and in vivo.Results We investigated the influence of bovine lactoferrin(bLF)on the microbiome of healthy and infected weaned piglets.Additionally,we assessed whether bLF influenced the immune responses upon Shiga toxin-producing E.coli(STEC)infection.Therefore,2 in vivo trials were conducted:a microbiome trial and a challenge infection trial,using an F18+STEC strain.BLF did not affect theα-andβ-diversity.However,bLF groups showed a higher relative abundance(RA)for the Actinobacteria phylum and the Bifidobacterium genus in the ileal mucosa.When analysing the immune response upon infection,the STEC group exhibited a significant increase in F18-specific IgG serum levels,whereas this response was absent in the bLF group.Conclusion Taken together,the oral administration of bLF did not have a notable impact on theα-andβ-diversity of the gut microbiome in weaned piglets.Nevertheless,it did increase the RA of the Actinobacteria phylum and Bifi-dobacterium genus,which have previously been shown to play an important role in maintaining gut homeostasis.Furthermore,bLF administration during STEC infection resulted in the absence of F18-specific serum IgG responses.
基金supported by Pancosma SA,Geneva,Switzerland,Jastro & Shields Graduate Research Awardthe United States Department of Agriculture (USDA) National Institute of Food and Agriculture (NIFA),multistate projects W4002 and NC1202
文摘Background Our previous study has reported that supplementation of oligosaccharide-based polymer enhances gut health and disease resistance of pigs infected with enterotoxigenic E.coli(ETEC)F18 in a manner similar to carbadox.The objective of this study was to investigate the impacts of oligosaccharide-based polymer or antibiotic on the host metabolic profiles and colon microbiota of weaned pigs experimentally infected with ETEC F18.Results Multivariate analysis highlighted the differences in the metabolic profiles of serum and colon digesta which were predominantly found between pigs supplemented with oligosaccharide-based polymer and antibiotic.The relative abundance of metabolic markers of immune responses and nutrient metabolisms,such as amino acids and carbohydrates,were significantly differentiated between the oligosaccharide-based polymer and antibiotic groups(q<0.2 and fold change>2.0).In addition,pigs in antibiotic had a reduced(P<0.05)relative abundance of Lachnospiraceae and Lactobacillaceae,whereas had greater(P<0.05)Clostridiaceae and Streptococcaceae in the colon digesta on d 11 post-inoculation(PI)compared with d 5 PI.Conclusions The impact of oligosaccharide-based polymer on the metabolic and microbial profiles of pigs is not fully understood,and further exploration is needed.However,current research suggest that various mechanisms are involved in the enhanced disease resistance and performance in ETEC-challenged pigs by supplementing this polymer.
文摘This study was designed to find the susceptibility of Nitrofurantoin and Fosfomycin among urinary isolates of Escherichia.coli.Four hundred(400)urine samples were collected for susceptibility of nitrofurantoin and fosfomycin among urinary isolates of E.coli.All indoor and outdoor patients'urinary samples yielded growth of E.coli.Mid-stream urine specimens were inoculated on blood agar and CLED agar and incubated at 35±2°C.Growth was observed,and Escherichia coli was identified by Gram staining,Catalase,Motility test and API 20E(Bio murex)as per standard procedure.Antimicrobial susceptibility testing of isolates for nitrofurantoin and fosfomycin was carried out by the modified Kirby-Bauer disc diffusion method according to CLSI guidelines ATCC 25922.E.coli was used as a quality control strain.A total of 400 samples were tested susceptibility of nitrofurantoin and fosfomycin among urinary isolates of E.coli during this period.A total of 400 samples yielded the growth of E.coli,out of which 178(44.5%)were male and 222(55.5%)were female samples.Among males,18(10%)were tolerant to nitrofurantoin,and 2(1.1%)were tolerant to fosfomycin.Among females,9(4.09%)were susceptible to nitrofurantoin while 6(2.72%)were susceptible to fosfomycin.Among age groups below 45 years old,6(4.76%)were tolerant to nitrofurantoin,and 2(1.58%)were sensitive to fosfomycin.Between 46-66 years old,4(2.81%)were sensitive to nitrofurantoin,and 3(2.11%)were sensitive to fosfomycin.Between 67-90 years old,17(12.87%)were sensitive to nitrofurantoin,and 4(3.03%)were tolerant to fosfomycin.Fosfomycin and nitrofurantoin showed good susceptibility in urinary isolates of E.coli and can be used empirically in our setup.
基金the Natural Science Fundation of Jiangsu Province,№BK95141307
文摘Calmodulin (CaM), widely distributed in almost all eukaryotic cells, is a major intracellular calcium receptor responsible for mediating the Ca2 + signal to a multitude of different enzyme systems and is thought to play a vital role in the regulation of cell proliferative cycle[1,2]. Recently, many studies showed that CaM is also present in extracellular fluid such as cell culture media and normal body fluid and has been reported to stimulate proliferation in a range of normal and neoplastic cells, apparently acting as an autocrine growth factor[3-11]. In 1988, Crocker et al reported for the first time that addition of extracellular pure pig brain CaM could promote DNA synthesis and cell [7]proliferation in K562 human leukaemic lymphocytes[7].After that, more and more research was done on extracellular CaM and evidences demonstrated that extracellular CaM could also stimulate cell proliferation in normal human umbilical vein endothelial cells[5], keratinocytes[4], suspension-cultured cells of Angelica Dahurica, etc[6]. CaM is a monomeric protein of 148 amino acids that contains four homologous Ca2 + -binding domains. CaM has been highly conserved throughout the evolution. Only 1 out of 148 amino acids of human CaM is different from that of fish CaM. Complementary DNAs encoding rat, eel, chicken, human, and trypanosome CaM have been cloned.
基金This work was supported by National Natural Science Foundation of China 30070038 and 30130070, National High-Tech Research and Development Program of China (863 Project) 2001AA215391, and EU Project QLRT 2000 01441.
文摘Objective To report a protocol using biotin-labelled PrP protein in cell free conversion assay instead of isotope. Methods A hamster PrP protein (HaPrP) was expressed in E. coli and purified with HIS-tag affinity chromatograph. After being labelled with biotin, HaPrP was mixed with PrP^sen preparation from scrapie strain 263K. Results Protease-resistant bands were detected after four-day incubation. Conclusion The new conversion model provides a reliable, easily handling, and environment-friendly method for studies of prion and transmissible spongiform encephalopathies.
基金supported by the State Scholarship Fund from China Scholarship Council (No.2003850064)Chongqing Educational Committee Foundation (cq20070319).
文摘Objective: To construct recombinant E.coli LLO/OVA and investigate its tumor metastatic inhibition effect in B16 OVA melanoma challenged mice. Methods: Recombinant E.coli LLO/OVA was constructed and the expression of listeriolysin O (LLO) and ovalbumin (OVA) of the vaccine was determined by coomassie brilliant blue staining and western blotting, After 3 subcutaneous injections of E.coli LLO/OVA, the percentages of CD3^+CD4^+T, CD4^+CD25^+T, CD3^CD8^+T and OVA257-264 SIINFEKL specific CD8^+T cells were determined by flow cytomytry, and the tumor metastatic inhibition effect in B16 OVA melanoma challenged mice was observed. Results: Recombinant E.coli LLO/OVA was successfully constructed, and the expression of LLO and OVA of the vaccine was confirmed. After 3 subcutaneous injections of E.coli LLO/OVA and E.coli OVA in mice, the percentages of CD3^+CD4^+T, CD4^+CD25^+T and CD3^+CD8^+T cells were equivalent in the two groups of mice. However, there were significantly more OVA257-264 SIINFEKL specific CD8^+T cells in E.coli LLO/OVA vaccinated mice than that in E.coli OVA vaccinated mice. The prophylactic E.coli LLO/OVA vaccination effectively prevented the tumor metastasis to lungs in B16 OVA melanoma challenged mice. Depletion of CD8^+T cells significantly impaired the tumor inhibition effect of the vaccine in B16 OVA challenged mice. The therapeutic vaccination of E.coli LLO/OVA significantly prevented melanoma metastasis to lungs in B I6 OVA challenged mice too. Conclusion: Recombinant E.coli LLO/OVA vaccination is highly effective in inhibiting murine malignant melanoma metastasis by promoting CD8^+T cell immunity.
基金supported by a grant from the State Scholarship Fund under the China Scholarship Council (No.2003850064)the Chongqing Education Commission (KJ080319)
文摘Objective To explore the immune stimulation effect of recombinant E.coli LLO/OVA on mice bone marrow-derived dendritic cells (BMDCs) and T lymphocytes in vitro.Methods After BMDCs stimulated by E.coli LLO/OVA,their Toll-like receptor (TLR) and nucleotide-binding oligomerization domain (NOD) receptor signalling pathway were examined by superarray hybridization;and the priming effect of the vaccine activated BMDCs on CD4+T and CD8+T was determined by [3H]thymidine uptake and ELISA,the tumor cytotoxic effect of activated CD8+T cells was determined by cytotoxic assay.Results After BMDCs were activated by E.coli LLO/OVA via TLR4,NOD1 receptor and NF-κB signalling pathway,the expression of their surface molecules including MHC class Ⅰ,MHC class Ⅱ,CD40,CD80 and CD86 significantly up-regulated;the secretion of IL-12 and IFN-? increased also.The mature BMDCs stimulated the allergic CD4+T and CD8+T cells proliferation and their IL-2 and IFN-γ secretion,and the activated CD8+T cells effectively killed B16-OVA melanoma cells and RMA-S/OVA lymphoma cells in vitro.Conclusion E.coli LLO/OVA is effective in inducing BMDCs maturation via activating TLR4 and NOD1 receptor signalling pathway and promoting specific anti-tumor T cell immunity in vitro.
基金supported by grants from the Wuhan Science and Technology Bureau(No.02.07.17040008.05)the Fundamental Research Funds for the Central Universities(2042020kf0099)the Opening Foundation of Hubei Key Laboratory(No.2021KFY054).
文摘Objective To explore the role of extracellular vesicles(EVs)in the pathogenesis of glaucoma caused by E50K mutation.Methods A photoreceptor cell line,RGC-5,was transfected with empty plasmids and plasmids expressing wild-type(WT)optineurin(OPTN)or E50K OPTN to investigate the effects of OPTN glaucoma as well as to identify the role of EVs in glaucoma pathology.The RGC-5 cells were also stimulated with glutamate,and their viability was evaluated using flow cytometry or CCK-8 assay.EVs were extracted,labeled with PKH-26,and added into the medium for normal RGC-5 culture,and the status of the cells was observed thereafter.Results WT OPTN overexpression,E50K OPTN,and glutamate stimulation induced apoptosis of RGC-5 cells.However,when glutamate stimulation was used as an add-on treatment,the degree of apoptosis in WT OPTN-overexpressing RGC-5 cells was significantly lower than that in E50K OPTN-expressing and normal RGC-5 cells.The viability of normal RGC-5 cells was reduced when co-cultured with WT OPTN-overexpressing RGC-5 or E50K OPTN-overexpressing RGC-5.EVs released by the latter two transfected lines similarly reduced normal RGC-5 survival.Conclusion Our results indicate that WT OPTN overexpression may lead to photoreceptor apoptosis.However,overexpression also confers a degree of protection against high concentrations of extracellular glutamate.Additionally,EVs released by transfected RGC-5 cells may regulate the cell state.These findings may improve our understanding of the mechanisms of cell-cell interactions in pathological conditions,providing a basis for the use of EVs as novel targets for early diagnosis and treatment of glaucoma.
基金Funded by the National Natural Science Foundation of China (No. 50702040)
文摘The photocatalytic degradation of E.coli membrane cell by ZnO nanowires was studied using field-emission scanning electron microscope(FE-SEM),fluorescence microscopy,and Attenuated total reflection fourier transform infrared(ATR-FTIR).The outer membrane of E.coli was removed completely in the presence of ZnO nanowires under UV irradiation,and the cells became twisted shapes without a mechanically strong network.After ZnO nanowires photocatalysis,the permeability of the treated cells increased to some degree that could be confirmed by quantum dots labeling technique.Structural changes in the cell wall membrane were revealed by the decay of the characteristic groups bands in ATR-FTIR spectra.
文摘To explore the role of bcl-2 and bax genes in the apoptosis of human U937 cells induced by E.coli, flow cytometry assay with annexinⅤ-FITC/PI double staining was used to determine the condition of apoptosis, and the expressions of mRNA of bcl-2 and bax genes were assayed with RT-PCR. It was found that the apoptosis of human U937 cells could be induced by E.coli at various concentration ratios between cells and bacteria for 30 min in a dose-dependent manner. The apoptotic rates at cell/bacteria ratios of 0, 1∶5, 1∶10, 1∶20, 1∶50 and 1∶100 were 3.16%±0.90%, 9.46%±0.84%, 17.90%±1.41%, 35.59%±3.76%, 38.35%±7.12% and 55.07%±5.82% respectively. Also, there was a tendency of alterations in the expression levels of bcl-2 and bax genes with an increased expression level of bax gene and a reduced expression level of bcl-2 gene. It is concluded that E.coli can induce apoptosis in human U937 cells with a down-regulated expression of Bcl-2 and an up-regulated expression of Bax, and this might be related to the induction of apoptosis of the infected cell.
基金the Wuhan University Medical Faculty Innovation Seed Fund Cultivation Project(No.TFZZ2018025)the Chen Xiao-ping Foundation for the Development of Science and Technology of Hubei Province(No.CXPJJH12000001-2020313)the National Natural Science Foundation of China(No.81670123 and No.81670144).
文摘Objective Pseudogenes are initially regarded as nonfunctional genomic sequences,but some pseudogenes regulate tumor initiation and progression by interacting with other genes to modulate their transcriptional activities.Olfactory receptor family 7 subfamily E member 47 pseudogene(OR7E47P)is expressed broadly in lung tissues and has been identified as a positive regulator in the tumor microenvironment(TME)of lung adenocarcinoma(LUAD).This study aimed to elucidate the correlation between OR7E47P and tumor immunity in lung squamous cell carcinoma(LUSC).Methods Clinical and molecular information from The Cancer Genome Atlas(TCGA)LUSC cohort was used to identify OR7E47P-related immune genes(ORIGs)by weighted gene correlation network analysis(WGCNA).Based on the ORIGs,2 OR7E47P clusters were identified using non-negative matrix factorization(NMF)clustering,and the stability of the clustering was tested by an extreme gradient boosting classifier(XGBoost).LASSO-Cox and stepwise regressions were applied to further select prognostic ORIGs and to construct a predictive model(ORPScore)for immunotherapy.The Botling cohorts and 8 immunotherapy cohorts(the Samstein,Braun,Jung,Gide,IMvigor210,Lauss,Van Allen,and Cho cohorts)were included as independent validation cohorts.Results OR7E47P expression was positively correlated with immune cell infiltration and enrichment of immune-related pathways in LUSC.A total of 57 ORIGs were identified to classify the patients into 2 OR7E47P clusters(Cluster 1 and Cluster 2)with distinct immune,mutation,and stromal programs.Compared to Cluster 1,Cluster 2 had more infiltration by immune and stromal cells,lower mutation rates of driver genes,and higher expression of immune-related proteins.The clustering performed well in the internal and 5 external validation cohorts.Based on the 7 ORIGs(HOPX,STX2,WFS,DUSP22,SLFN13,GGCT,and CCSER2),the ORPScore was constructed to predict the prognosis and the treatment response.In addition,the ORPScore was a better prognostic factor and correlated positively with the immunotherapeutic response in cancer patients.The area under the curve values ranged from 0.584 to 0.805 in the 6 independent immunotherapy cohorts.Conclusion Our study suggests a significant correlation between OR7E47P and TME modulation in LUSC.ORIGs can be applied to molecularly stratify patients,and the ORPScore may serve as a biomarker for clinical decision-making regarding individualized prognostication and immunotherapy.