Objective To recover broad-neutralizing monoclonal antibodies(Bn Abs)from avian influenza A(H5N1)virus infection cases and investigate their genetic and functional features.Methods We screened the Abs repertoires of e...Objective To recover broad-neutralizing monoclonal antibodies(Bn Abs)from avian influenza A(H5N1)virus infection cases and investigate their genetic and functional features.Methods We screened the Abs repertoires of expanded B cells circulating in the peripheral blood of H5N1 patients.The genetic basis,biological functions,and epitopes of the obtained Bn Abs were assessed and modeled.Results Two Bn Abs,2-12 D5,and 3-37 G7.1,were respectively obtained from two human H5N1 cases on days 12 and 21 after disease onset.Both Abs demonstrated cross-neutralizing and Ab-dependent cellular cytotoxicity(ADCC)activity.Albeit derived from distinct Ab lineages,i.e.,V^H1-69-D2-15-JH^4(2-12D5)and V^H1-2-D3-9-JH^5(3-32 G7.1),the Bn Abs were directed toward CR6261-like epitopes in the HA stem,and HA2 I45 in the hydrophobic pocket was the critical residue for their binding.Signature motifs for binding with the HA stem,namely,IFY in VH1-69-encoded Abs and LXYFXW in D3-9-encoded Abs,were also observed in 2-12D5 and 3-32 G7.1,respectively.Conclusions Cross-reactive B cells of different germline origins could be activated and re-circulated by avian influenza virus.The HA stem epitopes targeted by the Bn Abs,and the two Ab-encoding genes usage implied the VH1-69 and D3-9 are the ideal candidates triggered by influenza virus for vaccine development.展开更多
目的:研究沉默大鼠肾组织中通用控制核苷酸合成5(general control nonderepressible 5,GCN5)基因、性别决定区Y框蛋白9(SRY related HMG box-9,SOX9)基因对Thy-1肾炎(Thy-1 nephritis,Thy-1N)大鼠肾组织内转化生长因子-β1(transforming...目的:研究沉默大鼠肾组织中通用控制核苷酸合成5(general control nonderepressible 5,GCN5)基因、性别决定区Y框蛋白9(SRY related HMG box-9,SOX9)基因对Thy-1肾炎(Thy-1 nephritis,Thy-1N)大鼠肾组织内转化生长因子-β1(transforming growth factor-β1,TGF-β1)生成的影响。方法:分别用慢病毒(lentivirus,LV)包装GCN5和SOX9发夹状小干扰RNA(shRNA),即制备LV-shGCN5和LV-shSOX9重组病毒。然后行大鼠肾动脉灌注术将LV-shGCN5和LV-shSOX9分别导入大鼠肾脏,再经尾静脉注射兔抗大鼠胸腺细胞抗血清(anti-thymocyte serum,ATS)复制Thy-1N模型。在注射ATS后3 h,取大鼠肾组织,用RTPCR和Western blot检查各组大鼠肾组织中GCN5和SOX9的mRNA及蛋白表达水平,以验证干扰效果及GCN5、SOX9对TGF-β1产生的影响。结果:利用肾动脉灌注术将LV-shGCN5或LV-shSOX9重组病毒导入大鼠肾组织后,不仅能有效沉默相应的靶基因,而且还能下调TGF-β1的表达。结论:沉默大鼠肾组织中GCN5或SOX9基因后能显著抑制Thy-1N大鼠肾内TGF-β1的生成。展开更多
基金supported by the General Program of the National Natural Science Foundation of China[No.31570162]the National Key Research Program[No.2016YFC1200200].
文摘Objective To recover broad-neutralizing monoclonal antibodies(Bn Abs)from avian influenza A(H5N1)virus infection cases and investigate their genetic and functional features.Methods We screened the Abs repertoires of expanded B cells circulating in the peripheral blood of H5N1 patients.The genetic basis,biological functions,and epitopes of the obtained Bn Abs were assessed and modeled.Results Two Bn Abs,2-12 D5,and 3-37 G7.1,were respectively obtained from two human H5N1 cases on days 12 and 21 after disease onset.Both Abs demonstrated cross-neutralizing and Ab-dependent cellular cytotoxicity(ADCC)activity.Albeit derived from distinct Ab lineages,i.e.,V^H1-69-D2-15-JH^4(2-12D5)and V^H1-2-D3-9-JH^5(3-32 G7.1),the Bn Abs were directed toward CR6261-like epitopes in the HA stem,and HA2 I45 in the hydrophobic pocket was the critical residue for their binding.Signature motifs for binding with the HA stem,namely,IFY in VH1-69-encoded Abs and LXYFXW in D3-9-encoded Abs,were also observed in 2-12D5 and 3-32 G7.1,respectively.Conclusions Cross-reactive B cells of different germline origins could be activated and re-circulated by avian influenza virus.The HA stem epitopes targeted by the Bn Abs,and the two Ab-encoding genes usage implied the VH1-69 and D3-9 are the ideal candidates triggered by influenza virus for vaccine development.
