Objective： This study aimed to express a fusion protein of diphtheria toxin and human B cell-activating factor （DT388sBAFF） in Escherichia coli （E. coli） and investigate its activity in human B-lineage acute lymp...Objective： This study aimed to express a fusion protein of diphtheria toxin and human B cell-activating factor （DT388sBAFF） in Escherichia coli （E. coli） and investigate its activity in human B-lineage acute lymphoblastic leukemia 1 cells （BALL-1）. Methods： A fragment of DT388sBAFF fusion gene was separated from plasmid pUC57-DT388sBAFF digested with Nde I and Xho I, and inserted into the expression vector pcold II digested with the same enzymes. Recombinants were screened by the colony polymerase chain reaction （PCR） and restriction map. The recombinant expression vector was transformed into BL21 and its expression was induced by isopropyl β-D-1-thiogalactopyranoside （IPTG）. The recombinant protein was identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis （SDS-PAGE） and Western blot, and then purified by Ni2＋-NTA affinity chromatography. The expression level of B cell-activating factor receptor （BAFF-R） on BALL-1 cells was assessed by real-time PCR. The receptor binding capacity of recombinant protein was determined by cell fluorescent assay. The specific cytotoxicity of recombinant protein on BALL-1 cells was detected by 3-（4,5-dimethylthiazolyl-2）-2,5-diphenyltetrazolium bromide （MTT） assay. Results： The expression level of recombinant protein was 50% of total bacterial proteins in E. coli, and the recombinant protein could bind to BAFF-R-positive BALL-1 cells and thereby produce a cytotoxic effect on the cells. Conclusion： The fusion protein expression vector DT388sBAFF was successfully constructed and the recombinant protein with selective cytotoxicity against BALL-1 cells was obtained, providing foundation for further study of the therapy of human B-lineage acute lymphoblastic leukemia.展开更多
Objective To study the effect of baicalin on the expression of receptor activator of nuclear factor-κB ligand(RANKL)and osteoprotegerin(OPG)in cultured human periodontal ligament(HPDL)cells.Methods Small interfering ...Objective To study the effect of baicalin on the expression of receptor activator of nuclear factor-κB ligand(RANKL)and osteoprotegerin(OPG)in cultured human periodontal ligament(HPDL)cells.Methods Small interfering RNA(siRNA)eukaryotic expression vector targeted transforming growth factor βⅡ receptor(TGF-β RⅡ)was constructed and transfected into T cells.HPDL cells with T cells transfected with siRNA or not were placed in the culture medium that had been added with lipopolysaccharide(LPS)and baicalin.The obtained solution was divided into six groups according to the components(group Ⅰ:HPDL cells+LPS+T cells transfected with siRNA1+baicalin;group Ⅱ:HPDL cells+LPS+T cells transfected with siRNA1;group Ⅲ:HPDL cells+LPS+T cells+baicalin;group Ⅳ:HPDL cells+LPS+T cells;group Ⅴ:HPDL cells+baicalin;group Ⅵ:HPDL cells)and was cultured for 48 hours.RT-PCR was used to observe the effect of baicalin on the expression of OPG-RANKL in HPDL cells.Results The ratio of RANKL/OPG in group Ⅰ was lower than that in group Ⅱ(P<0.01)and higher than that in group Ⅲ(P<0.01);The ratio of RANKL/OPG in group Ⅲ was lower than that in group Ⅳ(P<0.01);the ratio of RANKL/OPG in group Ⅳ was higher than that in group Ⅵ(P<0.01);the ratio of RANKL/OPG in group Ⅴ was lower than that in group Ⅵ(P<0.05).Conclusion ① Baicalin could decrease the ratio of RANKL/OPG in HPDL cells.② The TGF-β signaling transduction plays an important role in the effect of baicalin on the RANKL/OPG ratio in HPDL cells.③ Baicalin acts not only through TGF-β to regulate RANKL/OPG in HPDL cells,but also through other pathways.展开更多
OBJECTIVE To investigate the contribution of B cell activating factor of TNF family(BAFF)in the proliferation and activation of B cell in rheumatoid arthritis(RA),and to clarify whether high levels of BAFF is associat...OBJECTIVE To investigate the contribution of B cell activating factor of TNF family(BAFF)in the proliferation and activation of B cell in rheumatoid arthritis(RA),and to clarify whether high levels of BAFF is associated with clinical variables and lab parameters.METHODS Blood samples and peripheral blood mononuclear cells from RA patients and healthy controls(HCs)were collected and isolated respectively.Clinical variables and lab parameters,BAFF level,cytokines and immunoglobulins in serum were evaluated at entry.B cell subpopulations,BAFF receptors(BAFFR,BCMA,TACI),and alternative and canonical NF-κB pathway in B cell were analyzed in vivo and in vitro.RESULTS In RA patients,BAFF level and activated B cell subsets increased significantly.BAFF level was associated with CRP,RF,DAS28,swollen joint counts and tender joint counts.BAFFR,BCMA,TACI on B cells in RA over expressed.The expressions of MKK3,MKK6,p-p38,p-NF-κB65,TRAF2,NF-κB52 were higher than that in HCs.In vitro,BAFF up regulated activated B cell subset and the expressions of BAFFR,BCMA and TACI.BAFF also enhanced the expressions of MKK3,MKK6,p-p38,p-NF-κB65,TRAF2,NF-κB52.CONCLUSION Increased BAFF in serum is associated with the disease activity of RA,BAFF involves in the proliferation and activation of B cell in RA through alternative and canonical NF-κB pathway,indicating that BAFF might be a novel biomarker of diagnosis and therapy.展开更多
基金supported by grants from the National "973" Basic Research Program of China (No.2012CB944703)the National Key Technology Research and Development Program of China (No.2011BAI17B00)the Shandong Provincial Science and Technology Development Projects (No.2009GG10002008 and No.2011GSF12103)
文摘Objective： This study aimed to express a fusion protein of diphtheria toxin and human B cell-activating factor （DT388sBAFF） in Escherichia coli （E. coli） and investigate its activity in human B-lineage acute lymphoblastic leukemia 1 cells （BALL-1）. Methods： A fragment of DT388sBAFF fusion gene was separated from plasmid pUC57-DT388sBAFF digested with Nde I and Xho I, and inserted into the expression vector pcold II digested with the same enzymes. Recombinants were screened by the colony polymerase chain reaction （PCR） and restriction map. The recombinant expression vector was transformed into BL21 and its expression was induced by isopropyl β-D-1-thiogalactopyranoside （IPTG）. The recombinant protein was identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis （SDS-PAGE） and Western blot, and then purified by Ni2＋-NTA affinity chromatography. The expression level of B cell-activating factor receptor （BAFF-R） on BALL-1 cells was assessed by real-time PCR. The receptor binding capacity of recombinant protein was determined by cell fluorescent assay. The specific cytotoxicity of recombinant protein on BALL-1 cells was detected by 3-（4,5-dimethylthiazolyl-2）-2,5-diphenyltetrazolium bromide （MTT） assay. Results： The expression level of recombinant protein was 50% of total bacterial proteins in E. coli, and the recombinant protein could bind to BAFF-R-positive BALL-1 cells and thereby produce a cytotoxic effect on the cells. Conclusion： The fusion protein expression vector DT388sBAFF was successfully constructed and the recombinant protein with selective cytotoxicity against BALL-1 cells was obtained, providing foundation for further study of the therapy of human B-lineage acute lymphoblastic leukemia.
基金supported by the Foundation of Stomatology Hospital,Xi'an Jiaotong University
文摘Objective To study the effect of baicalin on the expression of receptor activator of nuclear factor-κB ligand(RANKL)and osteoprotegerin(OPG)in cultured human periodontal ligament(HPDL)cells.Methods Small interfering RNA(siRNA)eukaryotic expression vector targeted transforming growth factor βⅡ receptor(TGF-β RⅡ)was constructed and transfected into T cells.HPDL cells with T cells transfected with siRNA or not were placed in the culture medium that had been added with lipopolysaccharide(LPS)and baicalin.The obtained solution was divided into six groups according to the components(group Ⅰ:HPDL cells+LPS+T cells transfected with siRNA1+baicalin;group Ⅱ:HPDL cells+LPS+T cells transfected with siRNA1;group Ⅲ:HPDL cells+LPS+T cells+baicalin;group Ⅳ:HPDL cells+LPS+T cells;group Ⅴ:HPDL cells+baicalin;group Ⅵ:HPDL cells)and was cultured for 48 hours.RT-PCR was used to observe the effect of baicalin on the expression of OPG-RANKL in HPDL cells.Results The ratio of RANKL/OPG in group Ⅰ was lower than that in group Ⅱ(P<0.01)and higher than that in group Ⅲ(P<0.01);The ratio of RANKL/OPG in group Ⅲ was lower than that in group Ⅳ(P<0.01);the ratio of RANKL/OPG in group Ⅳ was higher than that in group Ⅵ(P<0.01);the ratio of RANKL/OPG in group Ⅴ was lower than that in group Ⅵ(P<0.05).Conclusion ① Baicalin could decrease the ratio of RANKL/OPG in HPDL cells.② The TGF-β signaling transduction plays an important role in the effect of baicalin on the RANKL/OPG ratio in HPDL cells.③ Baicalin acts not only through TGF-β to regulate RANKL/OPG in HPDL cells,but also through other pathways.
基金The project supported by National Natural Science Foundation of China(81473223,31100640,81302517 and 81330081)China Postdoctoral Science Foundation(2013M540509)
文摘OBJECTIVE To investigate the contribution of B cell activating factor of TNF family(BAFF)in the proliferation and activation of B cell in rheumatoid arthritis(RA),and to clarify whether high levels of BAFF is associated with clinical variables and lab parameters.METHODS Blood samples and peripheral blood mononuclear cells from RA patients and healthy controls(HCs)were collected and isolated respectively.Clinical variables and lab parameters,BAFF level,cytokines and immunoglobulins in serum were evaluated at entry.B cell subpopulations,BAFF receptors(BAFFR,BCMA,TACI),and alternative and canonical NF-κB pathway in B cell were analyzed in vivo and in vitro.RESULTS In RA patients,BAFF level and activated B cell subsets increased significantly.BAFF level was associated with CRP,RF,DAS28,swollen joint counts and tender joint counts.BAFFR,BCMA,TACI on B cells in RA over expressed.The expressions of MKK3,MKK6,p-p38,p-NF-κB65,TRAF2,NF-κB52 were higher than that in HCs.In vitro,BAFF up regulated activated B cell subset and the expressions of BAFFR,BCMA and TACI.BAFF also enhanced the expressions of MKK3,MKK6,p-p38,p-NF-κB65,TRAF2,NF-κB52.CONCLUSION Increased BAFF in serum is associated with the disease activity of RA,BAFF involves in the proliferation and activation of B cell in RA through alternative and canonical NF-κB pathway,indicating that BAFF might be a novel biomarker of diagnosis and therapy.
