Gene Cloning,Expression and Immunoreactivity of a Single Chain-Fv-Fragment Antibody PS-9

The gene encoding the heavy-and light-chain Fv regions of monoclonal antibody PS-9,which recognizes a cancer-associated antigen S-Tn on the most adenocarcinoma,was clonedby PCR techniques.The light and heavy chains were connected by a flexible linker to form asingle chain variable fragment(ScFv)gene with 720bp,which was in turn fused topCANTAB 5 phage.The single chain Fv was expressed as fusion protein displayed on thephage surface.The phagemid is used to transform compepent E.Coli TG1 cells,then infect-ed with M13K07 helper phage to rescue the phagemid and antibody ScFv gene.All rand-mized 12 clones were shown reacting with colon cancer cell line Ls174t,which expresses S-Tnantigen.The recombinant phage has been infected E.Coli HB2151 cells to produe soluble an-tibody,which can be used for immunodetection and immunotherapy for cancer.

The gene encoding the heavy- and light-chain Fv regions of monoclonal antibody PS-9, which recognizes a cancer-associated antigen S-Tn on the most adenocarcinoma, was cloned by PCR techniques. The light and heavy chains were connected by a flexible linker to form a single chain variable fragment (ScFv) gene with 720 bp, which was in turn fused to pCANTAB 5 phage. The single chain Fv was expressed as fusion protein displayed on the phage surface. The phagemid is used to transform competent E. Coli TG1 cells, then infected with M13K07 helper phage to rescue the phagemid and antibody ScFv gene. All randomized 12 clones were shown reacting with colon cancer cell line Ls174t, which expresses S-Tn antigen. The recombinant phage has been infected E. Coli HB2151 cells to produce soluble antibody, which can be used for immunodetection and immunotherapy for cancer.