In order to improve the functional affinity of the humanized VH single domain antibody against human lung cancer, the genes coding the homogenous dimers dihu3D3Vn and tetramers tehu3D3VH were constructed by fusing the...In order to improve the functional affinity of the humanized VH single domain antibody against human lung cancer, the genes coding the homogenous dimers dihu3D3Vn and tetramers tehu3D3VH were constructed by fusing the SV5-Cys short peptide and p53 tetramefization structural domain gene to hu3D3VH gene via recombinant PCR technique, respectively. Then, the dihu3D3VH and tehu3D3VH genes were cloned to the prokaryotic expression vector pET-22b( + ) and expressed in E. coli BL21 (DE3). The proteins expressed were purified through Ni^2+ -affinity chromatographic column. Meanwhile, the hu3D3VH, dihu3D3VH and tehu3D3VH proteins were labeled with FTTC, and their reactivity with antigen and specificity were analyzed by immunofluorescence assay. As to their functional affinities, it was analyzed and compared by flow cytometry. The results indicated that these two genes were expressed as monomers and mainly as inclusion bodies. After purification and renaturation, there were about 50% of dimers and 70% of tetramer remaining in the protein solution. In addition, the dihu3D3VH and tehu3D3VH proteins still remained the reactivity with antigen and specificity of hu3D3VH protein, and their functional affinities were increased about 60% or 100% respectively, compared with those of hu3D3VH protein. It is evident that the functional affinity of hu3D3VH protein can be greatly improved by increasing its binding valency.展开更多
A water-soluble adjuvant named QuickAntibody (QA) was introduced into the procedure of mouse immunization for the development of hapten-specific monoclonal antibodies (mAbs), using four kinds of pesticides as mode...A water-soluble adjuvant named QuickAntibody (QA) was introduced into the procedure of mouse immunization for the development of hapten-specific monoclonal antibodies (mAbs), using four kinds of pesticides as model compounds. Compared with conventional Freund's adjuvants, QA treatments offered relatively low but acceptable antiserum titers after three inoculations, gave little adverse effects to the experimental animals, and were preferable in harvesting splenocytes during the steps of cell fusion. Afterwards, hybridomas from the QA group were prepared and screened by both non-competitive and competitive indirect enzyme-linked immunosorbent assays (ELISAs). The efficiency of gaining immune-positive hybridomas was satisfactory, and the resultant mAbs showed sensitivities (half maximal inhibitory concentration (IC50)) of 0.91, 2.46, 3.72, and 6.22 ng/ml to triazophos, parathion, chlorpyrifos, and fenpropathrin, respectively. Additionally, the performance of QA adjuvant was further confirmed by acquiring a high-affinity mAb against okadaic acid (IC50 of 0.36 ng/ml) after three immunizations. These newly developed mAbs showed similar or even better sensitivities compared with previously reported mAbs specific to the corresponding analytes. This study suggested that the easy-to-use adjuvant could be applicable to the efficient gen- eration of highly sensitive mAbs against small compounds.展开更多
文摘In order to improve the functional affinity of the humanized VH single domain antibody against human lung cancer, the genes coding the homogenous dimers dihu3D3Vn and tetramers tehu3D3VH were constructed by fusing the SV5-Cys short peptide and p53 tetramefization structural domain gene to hu3D3VH gene via recombinant PCR technique, respectively. Then, the dihu3D3VH and tehu3D3VH genes were cloned to the prokaryotic expression vector pET-22b( + ) and expressed in E. coli BL21 (DE3). The proteins expressed were purified through Ni^2+ -affinity chromatographic column. Meanwhile, the hu3D3VH, dihu3D3VH and tehu3D3VH proteins were labeled with FTTC, and their reactivity with antigen and specificity were analyzed by immunofluorescence assay. As to their functional affinities, it was analyzed and compared by flow cytometry. The results indicated that these two genes were expressed as monomers and mainly as inclusion bodies. After purification and renaturation, there were about 50% of dimers and 70% of tetramer remaining in the protein solution. In addition, the dihu3D3VH and tehu3D3VH proteins still remained the reactivity with antigen and specificity of hu3D3VH protein, and their functional affinities were increased about 60% or 100% respectively, compared with those of hu3D3VH protein. It is evident that the functional affinity of hu3D3VH protein can be greatly improved by increasing its binding valency.
基金supported by the Special Fund for Agro-scientific Research in the Public Interest(No.201203094-3)the Scientific Research Fund of Zhejiang Provincial Education Department(No.Y201329970)+1 种基金the National Natural Science Foundation of China(No.31401768)the Experimental Technology Research Project of Zhejiang University(No.SZD201404),China
文摘A water-soluble adjuvant named QuickAntibody (QA) was introduced into the procedure of mouse immunization for the development of hapten-specific monoclonal antibodies (mAbs), using four kinds of pesticides as model compounds. Compared with conventional Freund's adjuvants, QA treatments offered relatively low but acceptable antiserum titers after three inoculations, gave little adverse effects to the experimental animals, and were preferable in harvesting splenocytes during the steps of cell fusion. Afterwards, hybridomas from the QA group were prepared and screened by both non-competitive and competitive indirect enzyme-linked immunosorbent assays (ELISAs). The efficiency of gaining immune-positive hybridomas was satisfactory, and the resultant mAbs showed sensitivities (half maximal inhibitory concentration (IC50)) of 0.91, 2.46, 3.72, and 6.22 ng/ml to triazophos, parathion, chlorpyrifos, and fenpropathrin, respectively. Additionally, the performance of QA adjuvant was further confirmed by acquiring a high-affinity mAb against okadaic acid (IC50 of 0.36 ng/ml) after three immunizations. These newly developed mAbs showed similar or even better sensitivities compared with previously reported mAbs specific to the corresponding analytes. This study suggested that the easy-to-use adjuvant could be applicable to the efficient gen- eration of highly sensitive mAbs against small compounds.