ANTIBODIES POLYCLONAL MONOCLONAL Derived from different B Derived from a single B cell Lymphocytes cell lines. clone. Batch to Batch variation No Batch to Batch affecting Ab reactivity & variations. Effectiveness of treatment. Ab is much more predictable. NOT Powerful tools for Enable the development of clinical diagnostic tests. secure immunoassay systems.
1) Homogeneity: Monoclonal antibody represents a single antibody molecule that binds to antigens with the same affinity and promote the same effectors functions.2) Specificity:The product of a single hybridoma reacts with the same epitope on antigens.3) Immunizing Antigen:Need not be pure or characterized and is ultimately not needed to produce large quantities of antibody.4) Selection:It is possible to select for specific epitope specificities and generate antibodies against a wider range of antigenic determinants.5) Antibody Production:Unlimited quantities of a single well-defined monospecific reagent.
1) Affinity: Average affinity of monoclonal antibodies are generally lower than polyclonal antibodies.2) Effector Functions: Because antibody is monoclonal, it may not produce the desired biologic response.3) Specificity: Monoclonals against conformational epitopes on native proteins may lose reactivity with antigens.4) Cross reactions: Antibodies sometimes display unexpected crossreactions with unrelated antigens.5) Time and effort commitment: VERY LARGE.
1) FILTRATION METHOD:Cells, celldebris, lipids, andclotted material arefirstremoved, typically byfiltration with a 0.45um filter.
a) Most of the charged impurities are usually anions such as nucleic acids and endotoxins. These are often separated by ion exchange chromatography.b) column chromatography can also use which is much quicker method.
2) ANTIBODY HETEROGENEITY: Product heterogeneity is common to monoclonal antibody and other recombinant biological production and is typically introduced either upstream during expression or downstream during manufacturing. These variants are typically aggregates, deamidation products, glycosylation variants, oxidized amino acid side chains, as well as amino and carboxyl terminal amino acid additions. These seemingly minute changes in a monoclonal antibody’s structure can have a profound effect on preclinical stability and process optimization as well as therapeutic product potency, bioavailability, and immunogenicity. The generally accepted method of purification of process streams for monoclonal antibodies includes capture of the product target with Protein A, elution, acidification to inactivate potential Mammalian viruses, followed by cation exchange chromatography, and finally anion exchange chromatography.
Recombinant antibody engineering involves the useof viruses or yeast to create antibodies, rather thanmice. These techniques rely on rapid cloning ofimmunoglobulin gene segments to create libraries ofantibodies with slightly different aminoacid sequences from which antibodies with desiredspecificities can be selected. These techniques canbe used to enhance the specificity with whichantibodies recognize antigens, their stability invarious environmental conditions, their therapeuticefficacy, and their detect ability in diagnosticapplications. Fermentation chambers have beenused to produce these antibodies on a large scale.
In one approach, mouse DNA encoding thebinding portion of a monoclonal antibody wasmerged with human antibody-producing DNA inliving cells, and the expression ofthis chimeric DNA through cell culture yieldedpartially mouse, partially human monoclonalantibody. For this product, the descriptive terms"chimeric" and "humanised" monoclonalantibody have been used to reflect thecombination of mouse and human DNA sourcesused in the recombinant process.
A method to generate fully human monoclonal antibodiesusing blood from normal donors without previous exposureto the antigen. The technology uses to generate an antigenpresentation system, which emulates the naturalpresentation of antigens by the immune system.
Radio immunotherapy (RIT)Antibody-directed enzyme prodrugtherapy (ADEPT) Immunoliposomes
Monoclonal antibodies used for autoimmunediseases include infliximab and adalimumab, which are effective in rheumatoid arthritis, Crohnsdisease and ulcerative Colitis.Basiliximab and daclizumab activated T cells andthereby help preventing acute rejection of kidneytransplants.Omalizumab inhibits human immunoglobulin E(IgE) and is useful in moderate-to-severeallergic asthma.
Antibodies are used in several diagnostic tests todetect small amounts of drugs, toxins orhormones.e.g. monoclonal antibodies to human chorionicgonadotropin (HCG) are used in pregnancy testkits.Another diagnostic uses of antibodies is thediagnosis of AIDS by the ELISA test.
Antibody Brand name Type IndicationAbciximab ReoPro chimeric Cardiovascular diseaseAdalimumab Humira human Several auto-immune disordersAlemtuzumab Campath humanized Chronic lymphocytic leukemiaBasiliximab Simulect chimeric Transplant rejectionBelimumab Benlysta human Systemic lupus erythematosus Colorectal cancer, AgeBevacizumab Avastin humanized related macular degenerationBrentuximab Adcetris Chimeric Hodgkin lymphomaVedotin
Antibody Brand name Type IndicationCanakinumab Ilaris HumanCetuximab Erbitux chimeric Colorectal cancer, Head and neck cancerCertolizumab Cimzia humanized Crohns diseasepegolDaclizumab Zenapax humanized Transplant rejectionDenosumab Prolia , Xgeva Human Postmenopausal osteoporosisEculizumab Soliris humanized Paroxysmal nocturnal hemoglobinuriaEfalizumab Raptiva humanized Psoriasis
Antibody Brand name Type IndicationPalivizumab Synagis humanized Respiratory Syncytial VirusPanitumumab Vectibix human Colorectal cancerRanibizumab Lucentis humanized Macular degenerationRituximab Rituxan, chimeric Non-Hodgkin Mabthera lymphomaTocilizumab Actemra Humanised Rheumatoid arthritisTositumomab Bexxar murine Non-Hodgkin lymphomaTrastuzumab Herceptin humanized Breast cancer