Construction and evaluation of wild and mutant ofatumumab scFvs against the human CD20 antigen.

Several monoclonal antibodies targeting the CD20 have been produced and Ofatumumab is a case in point. Although whole antibodies target cancer cells effectively, their applications are restricted in some ways. Single-chain fragment variable antibodies, rather than employing the entire structure of antibodies, have proven a practical approach for creating completely functional antigen-binding fragments. In current research, the DNA coding sequence of V L and V H of the wild and mutant forms of ofatumumab were joined with a flexible linker ( GGGGS ) 3 separately. Using the E. coli BL21 (DE3) expression system, the V L -linker- V H genes were cloned into the pET-28 a (+), and the associated recombinant proteins were produced. Purified and refolded scFvs (scFv-C and scFv- V 3 ) represented a concentration of around 0.7 mg/ml from 1 L of initial E. coli culture with a molecular weight of about 27 kDa. Affinity measurement disclosed anti-CD20 scFv- V 3 possesses a higher affinity constant compared to anti-CD20 scFv- C . The recombinant scFvs exclusively attach to Raji cells but not to Jurkat cells, according to a cell-ELISA analysis. The MTT test signified anti-CD20 scFvs could affect cell viability in Raji cells but had no impact on Jurkat cells and also, Raji cells viability was affected more significantly by anti-CD20 scFv- V 3 .