Construction,expression and in vitro specific killing activity of a recombinant fusion protein:anti-CD20Fab-LDM / 中国药理学通报

ABSTRACT

Aim To construct and express anti-CD20Fab-LDP,generate anti-CD20Fab-LDM and identify its biological activity.Methods PCR and overlapping PCR were used to construct anti-CD20Fab-LDP.DNA sequence was analyzed by the Terminus of Dideoxy Nucleotide.The product was purified by affinity chromatography and analyzed by Western blot and its antigen-binding activity was examined by FACS.Specific killing activity in vitro of anti-CD20Fab-LDM was analyzed by MTT.Results The data of DNA sequence showed that anti-CD20Fab-LDP was correct.The fusion protein was recovered in high yield(up to 4 mg·L~(-1))after proteinG purification.The fusion protein could bind to Raji cells(CD20+),and similar affinity data were obtained with anti-CD20Fab.Anti-CD20Fab-LDP showed potent cytotoxicity to Raji cells with IC_(50) values of 0.9×10~(-10) mol·L~(-1).Conclusions Anti-CD20Fab-LDP with high level expression was successfully obtained and could bind to Raji cells cells.Anti-CD20Fab-LDM showed specific killing activity to Raji cells in vitro.