Phage-display Based Cloning and Characterization of Recombinant Antibody Fragments

Functional cloning of antibody genes became possible with the availability of a simple system for expressing antibody fragments such as scFv, Fab etc. in soluble form in E.coli. PCR amplified sequences can be assembled as scFv or Fab and cloned into expression vectors to isolate functional clones. Efficient screening method for display of antibody fragments on surface of bacteriophages, which also exploits the correct periplasmic folding of antibodies during phage biosynthesis helps isolate specific antibody fragments. The systematic use of phage display and whole domain randomization to obtain better folding scFv fragments can be used further for obtaining purified antibody fragments in large amounts using multi-step chromatographic purification procedure.Antibodies came to be used in almost all branches of biology, in laboratories, in biotechnology (e.g. biosensors and affinity chromatography), in chemical catalysis, tumor medicine, tissue targeting etc. However, for many applications, only the antigen-binding domains of antibody were required and the rest of the protein was unnecessary or even deleterious.