A human B cell line （3D5） that responds specifically to B cell growth factor （BCGF） hasbeen developed by a sequence of Staphylococcus aureus Cowen I activation,EB virus im-mortalization,and cloning.Proliferative r...A human B cell line （3D5） that responds specifically to B cell growth factor （BCGF） hasbeen developed by a sequence of Staphylococcus aureus Cowen I activation,EB virus im-mortalization,and cloning.Proliferative response to PHA-stimulated T cell supernatant（PHA-T-Sup） and nonresponsiveness to rIL-2 stimulation were factors used to screen positivecells.Phenotype analysis with a flow cytometer indicated that:1) 3D5 is a B cell line:100% of the cells were positive for B1 marker and 59% were positive for sIg,while T3and Mo 1 were negative:2) 3D5 is an activated B cell line:both Tac and 4F2 markersof activated （but not of resting） B cells were 100% positive:3) 3D5 expresses high molecularweight BCGF （HMW-BCGF） receptor-associated epitope BA5.3D5 cells proliferated inresponse to cpBCGF stimulation in a dose-dependent manner.HMW-BCGF also induced3D5 cells to proliferate.Interestingly.no proliferation could be detected in the presenceof rIL-2,rIL-4,or rIFN-r.The data show that 3D5 cells are specifically BCGF-responsiveB cells.Using 3D5 cells as target,BCGF activity was detected in crude BCGF preparationsedimented by 85% （NH<sub>4</sub>）<sub>2</sub>SO<sub>4</sub> and chromatographed in a DEAE-Sephadex A-25 column fromPHA-T-Sup.T24 cell supernatant with B cell differentiation factor （BCDF） activity couldnot induce 3D5 cells to differentiate into immunoglobulin-secreting cells.展开更多
In order to study the influence of rubidium(Rb)addition on the phase composition,microstructure,mechanical properties and cell response of bioactive glass-ceramics,CaO−SiO2−Na2O−B2O3−MgO−ZnO−P2O5 glass system was desi...In order to study the influence of rubidium(Rb)addition on the phase composition,microstructure,mechanical properties and cell response of bioactive glass-ceramics,CaO−SiO2−Na2O−B2O3−MgO−ZnO−P2O5 glass system was designed with and without addition of Rb.The results show that hydroxyapatite(HA)and Mg−whitelockite(Ca18Mg2H2(PO4)14)crystalline phases are formed in the glass matrix without Rb.After the addition of Rb,only HA phase is detected.The grain size of the crystals in the glass-ceramics is larger with the addition of Rb than that of samples without Rb.Rb addition can improve the bending strength of glass-ceramics.The cultivation of human bone marrow mesenchymal stem cells(hBMSCs)on Rb-containing glass-ceramics demonstrates enhanced cell adhesion,proliferation and ALP activity.In conclusion,Rb-modified glass-ceramics exhibit good mechanical property,excellent bioactivity and biocompatibility,which have potential for bone regeneration application.展开更多
文摘A human B cell line （3D5） that responds specifically to B cell growth factor （BCGF） hasbeen developed by a sequence of Staphylococcus aureus Cowen I activation,EB virus im-mortalization,and cloning.Proliferative response to PHA-stimulated T cell supernatant（PHA-T-Sup） and nonresponsiveness to rIL-2 stimulation were factors used to screen positivecells.Phenotype analysis with a flow cytometer indicated that:1) 3D5 is a B cell line:100% of the cells were positive for B1 marker and 59% were positive for sIg,while T3and Mo 1 were negative:2) 3D5 is an activated B cell line:both Tac and 4F2 markersof activated （but not of resting） B cells were 100% positive:3) 3D5 expresses high molecularweight BCGF （HMW-BCGF） receptor-associated epitope BA5.3D5 cells proliferated inresponse to cpBCGF stimulation in a dose-dependent manner.HMW-BCGF also induced3D5 cells to proliferate.Interestingly.no proliferation could be detected in the presenceof rIL-2,rIL-4,or rIFN-r.The data show that 3D5 cells are specifically BCGF-responsiveB cells.Using 3D5 cells as target,BCGF activity was detected in crude BCGF preparationsedimented by 85% （NH<sub>4</sub>）<sub>2</sub>SO<sub>4</sub> and chromatographed in a DEAE-Sephadex A-25 column fromPHA-T-Sup.T24 cell supernatant with B cell differentiation factor （BCDF） activity couldnot induce 3D5 cells to differentiate into immunoglobulin-secreting cells.
基金The authors are grateful for the financial supports from the Natural Science Foundation of Hunan Province,China(2019JJ50797)the Postdoctoral Science Foundation of China(2019T120711).
文摘In order to study the influence of rubidium(Rb)addition on the phase composition,microstructure,mechanical properties and cell response of bioactive glass-ceramics,CaO−SiO2−Na2O−B2O3−MgO−ZnO−P2O5 glass system was designed with and without addition of Rb.The results show that hydroxyapatite(HA)and Mg−whitelockite(Ca18Mg2H2(PO4)14)crystalline phases are formed in the glass matrix without Rb.After the addition of Rb,only HA phase is detected.The grain size of the crystals in the glass-ceramics is larger with the addition of Rb than that of samples without Rb.Rb addition can improve the bending strength of glass-ceramics.The cultivation of human bone marrow mesenchymal stem cells(hBMSCs)on Rb-containing glass-ceramics demonstrates enhanced cell adhesion,proliferation and ALP activity.In conclusion,Rb-modified glass-ceramics exhibit good mechanical property,excellent bioactivity and biocompatibility,which have potential for bone regeneration application.
