Screening of anti-idiotypic antibody to monoclonal antibody MC3 directed against colorectal carcinoma by phage antibody library technology / 中国免疫学杂志

ABSTRACT

Objective:To generate phage displayed anti idiotypic antibody single chain variable fragments(anti Id ScFv)to monoclonal antibody MC3 directed against colorectal carcinoma.Methods:Balb/c mice were immunized i.p. with MC3(McAb against colorectal Carcinoma) conjugated with KLH,and mRNA was isolated from the spleens of the immunized mice.VH and VL DNAs of the antibody were amplified separately and assembled into ScFv DNAs with a linker DNA by PCR.The ScFv DNAs were ligated into the phagemid vector pCANTAB5E and the ligated sample was transformed into competent E.coli TG1.The transformed cells were infected with M13KO7 helper phage to yield phage antibody ScFv library.After four rounds of panning to the library with MC3,the MC3 positive clones were selected by ELISA from the preselected phages.Results:The VH,VL and ScFv DNAs were about 340,320 and 750 bp respectively.After four rounds of panning to the antibody library,15 MC3 positive phage clones displayed anti Id ScFv were selected from 50 enriched phage clones.Conclusion:The phage displayed anti Id ScFv to MC3 were successfully selected by phage antibody library technology,which might provide new putative candidate molecules for developing recombinant anti Id vaccine of colorectal carcinoma.