Monoclonal Antibodies in Cancer Treatment

Research advances and promising clinical outcomes with immunotherapeutics has led to a resurgence of incorporating monoclonal antibodies in cancer treatment. Unconjugated, conjugated and multi-target constructs are emerging as a conventional form of therapy along with the classical trio of surgery, radiation and chemotherapy. The recent major accomplishments in monoclonals include: first, the development of human and chimeric structures negating the induction of humoral responses to murine counterparts which limited use; second, protein engineering has improved the affinity and specificity of the antibody to its target; third, technics have been designed to select monoclonal antibodies imparting a biological consequence (function) following binding; and, lastly, recombinant proteins are being created with multiple epitopic specificities and/or fusion with other biologically active proteins such as toxins and cytokines/growth factors. Clinical efficacy in the treatment of haematological malignancies has secured a role for monoclonals in routine treatment. Evidence of clinical responses in patients with metastatic solid tumours is leading to the next generation of trials in the adjuvant setting. This paper presents an overview of the clinical experience with monoclonal antibodies in cancer treatment over the past 5 years. Our aim is to highlight the successes and advances, as well as noting limitations of antibody therapeutics. The advances seen support a continued effort to optimise the creation, selection and use of immunotherapeutics in the battle against cancer.     

Monoclonal Antibodies Specific for Sendai Virus I. Production and Characterization of Monoclonal Antibodies

Twelve monoclonal antibodies specific for Sendai virus were prepared by fusing immune LOU rat spleen cells with Y3 or FO myeloma cells. Six antibodies bound the viral glycoprotein HN, and six the viral protein F. Among the six HN-specific monoclonal antibodies, five reacted with the very same epitope and inhibited viral haemagglutination. Two antibodies against the F protein recognized the same epitope, but all the others reacted with different epitopes. All monoclonals were characterized with regard to specificity, biological function, epitope recognition, isotypes, and pI.     

Monoclonal Antibodies against Human Monocytes

Three monoclonal antibodies (63D3, 63D2, and 61D3) with reactivity against human monocytes have been studied. They reacted with most adherent mononuclear cells but not with pure populations of peripheral blood B and T lymphocytes. Two of these antibodies, 63D3 and 63D2, competed in fluorescence inhibition experiments, recognized a monocyte surface antigem of about 200,000 daltons, and werre idiotypically related. The third antibody, 61D3, did not compete with the others in fluorescence inhibition experiments, recognized a different surface molecule, and was idiotypically distinct from 63D3 and 63D2. Whereas 63D3 and 63D2 reacted very weakly with some granulucytes, 61D3 did not, suggesting that it is specific for monocytes alone.