THE CONSTRUCTION AND EXPRESSION OF THE MURINE SCFV GENE IN E. COLI AGAINST HUMAN CERVICAL CANCER / 药物分析学报

Objective To obtain the gene of murine Single chain Fv fragment (ScFv) against human cervical cancer and to express it in E. coli. Methods The variable region gene fragments of the heavy and light chains, which were amplified respectively using recombinant DNA techniques from CsA125 hybridoma cells, were spliced together through a flexible linker to ScFv against human cervical cancer. The ScFv genes were then cloned into expression vector pCANTAB 5E and expressed in E. coli HB2151 and TG1 respectively. The soluble ScFv were characterized by SDS PAGE and Western blot. The antigen-binding activities of the soluble and phage displayed ScFv were assayed by ELISA and cell immunohistochemical analysis. Results The expressed ScFv antibodies were soluble and phage displayed. The soluble ScFv secreted and expressed in E. coli HB2151 induced by IPTG were confirmed with SDS-PAGE, Western blot and ELISA. The specific binding capacity of the soluble and phage displayed ScFv to the surface associated antigen of human cervical cancer cell line was further confirmed with immunohistochemical studies. Conclusion The soluble and phage displayed ScFv expressed in E. coli against human cervical cancer showed high, specific affinity for the cervical cancer cell line surface associated antigen.

Construction and identification of non-immunized human phage display library / 中国免疫学杂志

Objective:To develop non-immunized human phage display library.Methods:The total RNA of lymphocyte cells from peripheral blood of healthy voluntee was isolated and cDNA was synthesized,and the genes of heavy variable chain (VH) and light variable chain (V? and V?) were amplified by direct PCR and half-nested PCR.By overlapping extension PCR,the genes of VH and VL (V? and V?) were linked.The linked genes of single chain Fv fragment (scFv) were ligated with the vector pCANTAB-5E and then cloned into TG1 for the scFv library construction.Results:By direct PCR and half-nested PCR,42 VH fragments,16 V? and 18 V? fragments were obtained.The size of linked scFv library genes was 750 bp and the volume of constructed scFv library was 1.35?108.The results of BstN Ⅰ analysis of scFv genes from the phage library showed that fingerprint map of the selected scFvs was different.Conclusion:The developed phage library is diversity and can be used for selecting humanized scFv.