Monoclonal Antibodies in Diagnosis, Screening and Therapy - Monoclonal antibodies or specific antibodies, arc now an essential tool of much biomedical research and are of great commercial and medical value. For instance, ABO blood groups could be earlier identified with the help of human sera carrying antibodies of known specificity.

These human sera in U.K. have been replaced by monoclonal antibodies produced by hybridomas, for the identification of ABO blood groups. Thus the diagnostic and screening value of the monoclonal antibodies through serological tests has been demonstrated.

For instance, individual interferons could be purified using monoclonal antibodies and could be used for inactivating T lymphocytes responsible for rejection of organ transplants. Removal of tumour cells from bone marrow is another therapeutic use of monoclonal antibodies.

For therapeutic uses, monoclonal antibodies are so designed that they will neutralize the reaction or response by one defined antigen, but still preserve the reaction of all other antigens. Several antigens of T cell receptor complex, including CD3, CD4 and CD8 have been the targets of specific antibodies for therapy.

For many human diseases as above, murine (of mouse) antibodies are utilized. Their effectiveness is, however, limited due to their short survival time in humans and relatively low cytocidal effect.

For this reason, humanized antibodies are being produced by genetic manipulations and in future these will be increasingly utilized for therapy. Monoclonal antibodies cytotoxic agent conjugates called 'immunotoxins' have also been designed as carriers of cytotoxic substances to the target cells.