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MONOCLONAL ANTIBODIES. SEMINAR PRESENTATION Performed by PASCHALIS KOURELIAS MSc BIOMEDICAL IMMUNOLOGY EAST LONDON UNIVERSITY STRATFORD 09 /12/2003. WELCOME ABOARD. WELCOME TO THE MOST EXCITING DISCOVERY OF MODERN MOLECULAR IMMUNOLOGY.
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MONOCLONAL ANTIBODIES SEMINAR PRESENTATION Performed by PASCHALIS KOURELIAS MSc BIOMEDICAL IMMUNOLOGY EAST LONDON UNIVERSITY STRATFORD 09 /12/2003
WELCOME ABOARD • WELCOME TO THE MOST EXCITING DISCOVERY OF MODERN MOLECULAR IMMUNOLOGY. • THE JOURNEY TO THE WORLD OF MONOCLONAL ANTIBODIES STARTS JUST……… NOW !!!!!!!
WHAT IS AN ANTIBODY ? • ANTIBODIES or IMMUNOGLOBULINS ARE THE SECRETED FORM OF THE B-CELL ANTIGEN RECEPTOR (BCR) • THEY’RE MAIN ROLE IS TO BIND TO A FOREIGN ANTIGEN, AND THEN MEDIATE SECONDARY EFFECTS(ACTIVATION OF COMPLIMENT SYSTEM,RECRUITMENT OF PHAGOCYTES, OPSONIZATION). • THEY ARE REMARKABLY DIVERSE AND PROVIDE DIFFERENT COMBINE SITES TO RECOGNIZE THE MILLIONS OF ANTIGENIC SHAPES IN THE ENVIRONMENT.
WHAT IS MONOCLONAL ANTIBODY? PART 1 • MONOCLONAL ANTIBODIES (m-Abs), ARE Abs WHICH ARE GENERATED BY EXPANDING AND IMMORTALIZING SINGLE CLONES OF B-CELLS,EACH OF WHICH HAS A DEFINED SPECIFICITY.
WHAT IS MONOCLONAL ANTIBODY ? PART 2 • BECAUSE OF THE DEFINED SPECIFICITY THE mAbs RECOGNIZE JUST ONE ONLY EPITOPE ON THE ANTIGEN. • THE MONOCLONAL Abs WHICH DERIVED FROM ONE CLONE ARE ALMOST OF A SINGLE ISOTYPE
HOW WE CAN MAKE THEM I • THEY PRODUCED BY CELL LINES OR CLONES OBTAINED FROM ANIMALS (mainly mice) THAT HAVE BEEN IMMUNIZED WITH THE SUBSTANCE THAT IS SUBJECT OF STUDY. • AN ALTERNATIVE WAY IS TO TRASFORM B-CELLS (HUMAN B-CELS)BY INFECTED THEM WITH EPSTEIN-BARR VIRUS.
HOW WE CAN MAKE THEM II • TO PRODUCED THE DESIRED mAb, THE CELLS MUST BE GROWN IN EITHER OF TWO WAYS: • BY INJECTION INTO THE ABNOMINAL CAVITY OF A SUITABLY PREPARED MOUSE. • BY TISSUE CULTURING CELLS IN PLASTIC FLASKS.
SIGNIFICANCE-USE OF mAbs • mAbs ARE USED EXTENSIVELY IN BIOMEDICAL RESEARCH. • IN DIAGNOSIS OF A DISEASE, INFECTION. • IN TREATMENT OF A DISEASE • IN TREATMENT OF CANCER • IN SEROLOGICAL ASSAYS • AS MARKERS IN IDENTIFICATION OF PROTEINS,CARBOHYDRATES,NUCLEIC ACIDS.
USE OF MONOCLONAL Abs • MONOCLONAL Abs WERE ENVISAGED AS FORMING A VERY SPECIFIC HIGH AFFINITY DELIVERY SYSTEM FOR A TOXIN OR RADIOISOTOPE. • TO DELIVER A DAMAGING STIMULUS TO THE TUMOUR CELL OR VIRALLY INFECTED CELL WITHOUT HAVING ANY DETRIMENTAL EFFECT ON NORMAL NEIGHBOURING CELLS.
EFFECTS OF THE USE OF mAb • BECAUSE OF MICE (FOREIGN ORIGEN) THEY COULD INITIATE A XENOGENEIC EFFECT. • The production of human anti-mouse Abs • HAMA • LIMITED USEFULNESS AND APLLICATION AS THERAPEUTIC AGENTS. • The monoclonal Abs rapidly cleared from recipient’s system, by immune response.
HUMAN MONOCLONAL Abs • THE PROCESS IS MUCH MORE COMPLEX IN THE IMMUNISATION STAGES AND IN FUSION STEP. • MORE DIFFICULT TO PRODUCE IMMORTALISATION OF HUMAN ANTIDODY SECRETING CELLS. • ALTERNATIVE OPTIONS BECOME NECESSARY, AND BECOME AVAILABLE THANKS TO THE MAJOR ADVANCES OF GENETIC ENGINEERING AND RECOMBINANT DNA TECHNOLOGY.
CHIMERIC ANTIBODIES • GENETIC ENGINEERING AND GENE MANIPULATION HUMANISED THE MOUSE MONOCLONAL Abs. • POSSIBLE TO CLONE A V- region FROM A MOUSE ANTIBODY AND EXPRESS THIS GENE ALONG WITH A C- region OF THE REQUIRED TYPE. • XENOGENEIC EFFECT IS LIMITED • VAST REPERTOIRE OF V-regions OF m-Abs CAN BE UTILISED.
MOSAIC V-REGIONS • TO FURTHER HUMANISE THE MICE MOBOCLONAL Abs, MOSAIC V-region Abs, HAVE BEEN PRODUCED. • ONLY PORTIONS OF MOUSE ORIGIN ARE THE CDR’s. • HUMAN FWR AND C-regions. • LESS OF THE MOLECULE IS XENOGENEIC. • CHOICE OF C-regions ALLOWS THE TAILORINGOF THE MOLECULE TO A PARTICULAR PURPOSE
SUMMARY • MONOCLONAL Abs DERIVED FROM JUST ONLY A SIGLE CLONE. ALWAYS FROM THE SAME ISOTYPE. • GENERATE FROM MICE BY FUSING SPLEEN CELLS WITH A CANCER CELL (MYELOMA) or • BY USING IN VITRO TECHNIQUES. • HUMAN m-Abs ARE VERY LIMITED IN PRODUCTION DUE TO SEVERAL DIFFICULTIES. • THEY HAVE A GREAT USE IN MOLECULE MEDICINE. IN DIAGNOSIS-TREATMENT OF DISEASES INCLUDING CANCER. • SEVERAL METHODS HAVE BEEN DEVELOPED FOR HUMANISED THE MICE MONOCLONAL Abs. • CHIMERIC ANTIBODIES, MOSAIC V-regions,
ANY QUESTIONS ? ANY QUESTIONS ????
REFERENCES 1.Day,NE. Varghese C. (2001).25 years of monoclonal Antibodies. Immunology Today. Volume 32, No 8. 2.Avidan B, Sonneberg A.(2002). Role of monoclonal antibodies in molecular medicine. Journal of Immunology. Vol 97:1130-1135. 3. Blot W.J, Gefferson B. (2001). Humanised mice antibodies. Current opinion in Immunology35:403-409. 4. Gammon. MD.(2000).Monoclonal antibody. New England Journal Med. 405:362-365.