Abstract

A fantastic technological breakthrough was achieved by Milstein and Kohler who devised a technique for the production of immortal hybridoma cell lines making monoclonal antibody specific for a single epitope on a complex antigen.The availability of monoclonal antibodies has revived interest in immunotherapy.The ability to influence on individual's immune state by administering immunoglobulin of the appropriate specificity may provide a powerful approach to disease control and prevention. Monoclonal antibodies have tremendous applications In the field of diagnostics, therapeutics, targeted drug delivery systems, not only for infectious disease caused by bacteria, viruses and protozoa but also for cancer, metabolic and hormonal disorders. Looking at the pros and cons of traditional hybridoma technology for the production of monoclonal antibody, recombinant DNA technology has been used to engineer the chimeric monoclonal antibody, complementarity determining regions (CDR) grafted monoclonal antibodies, heteroconjugate antibodies and total recombinant monoclonal antibodies. Genetically engineered human antibody fragments can be derived by expanding the variable heavy (VH) and variable light (VL) chain genes from non-immunized, or preferably immunized donors and expressing them as completely randomised combinatorial libraries on the surface of bacteriophage. Recombinant antibodies can be expressed on a large scale in plants also.