* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Document
Survey
Document related concepts
Lymphopoiesis wikipedia , lookup
Complement system wikipedia , lookup
Duffy antigen system wikipedia , lookup
Gluten immunochemistry wikipedia , lookup
Sjögren syndrome wikipedia , lookup
DNA vaccination wikipedia , lookup
Psychoneuroimmunology wikipedia , lookup
Immune system wikipedia , lookup
Autoimmune encephalitis wikipedia , lookup
Innate immune system wikipedia , lookup
Adoptive cell transfer wikipedia , lookup
Molecular mimicry wikipedia , lookup
Adaptive immune system wikipedia , lookup
Immunocontraception wikipedia , lookup
Anti-nuclear antibody wikipedia , lookup
Cancer immunotherapy wikipedia , lookup
Polyclonal B cell response wikipedia , lookup
Transcript
BCH-751 Advances in Biotechnology 3(3-0) Theory Address advanced topics in microbial, animal and plant biotechnology such as biosensors, gene chip, gene silencing, immobilized biocatalysts. Gene therapy. Plants as bioreactor, tissue culture and transgenic plants. Bioremediations and biomass utilizations. Computer based modeling and drug designing. Books/Literature Recommended • Glick, B. R. and Pasternak, J. J. (1998, 2003, 2010). Molecular Biotechnology: 2nd, 3rd and 4th Eds. ASM Press, Washington, D. C. • Recent papers/review papers. http://www.uaar.edu.pk/user-categories.php Advance in Biotechnology (BCH 751), Biotechnology (BCH 713), Cellular Signaling (BCH 509), Cell Signaling Mechanisms (BCH 707), Fundamentals of Biotechnology (BCH 724), Genetic Engineering (BCH 712), Immunology (BIOL 723) and Principles of Biotechnology (BIOL 712) Categories and then Chapter wise Engineered Monoclonal Antibodies: Monoclonal antibodies have demonstrated enormous potential as new classes of drugs that confer great benefits to patients, and more than 40 therapeutic antibodies have already been approved for clinical use In particular, the past 5 years might be recognized as the period guiding the new era for “engineered antibodies,” with the successful approval of numerous antibody-drug conjugates, bispecific antibodies, and glycoengineered antibodies for clinical applications These therapeutic antibodies seem to be more promising with improved properties when compared to their ancestors There are several molecules in phase II/III clinical trails and few waiting for approvals Table – Phases of trail One drug, mogamulizumab (KW-0761 / POTELIGEO/ AMG761) has already received approval for marketing by Japanese Ministry of Health • It is defucosylated humanized mab derived from Kyowas Kirin’s “POTELLIGENT” technology which produces antibodies with enhanced antibody-dependent cell-mediated cytotoxicity (ADDC) activity • To be used for patients with relapsed or refractory CC kemokine receptor 4 (CCR4) positive adult T cell leukemia-lymphoma (ATL) Clinical Trials: Years Discovery/Preclinical Testing Phase 1 Phase 2 Phase 3 FDA 6.5 1.5 2 3.5 1.5 20 to 100 healthy volunteers 1,000 to 5,000 100 to 500 patient patient volunteers volunteers Test Population Laboratory and animal studies File IND at FDA Purpose Assess safety, biological activity, and formulations Determine safety and dosage Success Rate 5,000 compounds evaluated 5 enter trials Investigational New Drug (IND) New Drug Application (NDA) US Food and Drug Administration (FDA) Evaluate effectiveness, look for side effects Confirm effectiveness, monitor adverse reactions from long-term use File NDA Review process/ at FDA approval 1 approved Phase 4 Additional postmarketing testing required by FDA In addition, a large number of molecules are also in pre-clinical trials and are expected to progress through various stages of drug development over the next ten years By 2023, the over all market is estimated to be in the range of US $ 4.3 to 6.6 billion We will first discuss followings: i. Immune System ii. Antibody structure, function, production and uses (polyclonal and monoclonal) iii. Glycosylation i. Immune System: The human body provides two levels of protection from infectious diseases; • Non-specific resistance or innate immunity and • Specific resistance or adaptive immunity The principal components of innate immunity are; o Mechanical and chemical barriers o o o o • Phagocytosis Fever Inflammation and Acute phase proteins Mechanical barriers are the skin and the mucous membrane while chemical barriers are - Acidic gastric secretions Low pH of the skin Lysozyme Gastric and duodenal enzymes - Antibodies and inhibitors = Antibodies (IgA) are also found in tears and saliva - = Secretary IgA protects the body surface against invading pathogenic microbes Interferons - Complement proteins - Antimicrobial peptides In contrast to innate immunity, adaptive immunity is a more evolved and specific defense mechanism The characteristics of adaptive immunity are o Exquisite antigenic specificity and o The ability to “remember” different types of antigens Adaptive immunity is activated only against o Invading foreign material and o Never against its own molecules except in autoimmune diseases Therefore, it has the ability to distinguish between self and nonself Activation of the Immune Response: • There are two arms of the immune response: Humoral response mediated by B cells and antibodies and Cell-mediated response effected by T cells Fig from Science Fig 1.1 Roitt 7th Ed Fig 2.7 Khan 2009 Fig 1.7 Khan 2009 ii. Antibody’s Structure and Function: An antibody or immunoglobulin is a glycoprotein have a characteristic Yshaped structure produced by the body's immune system • When it detects harmful substances called antigens • Examples of antigens include microorganisms (such as bacteria, fungi, parasites, and viruses) and chemicals Antibodies may be produced when the immune system mistakenly considers healthy tissue a harmful substance. This is called an autoimmune disorder Figs down loaded from web site https://www.google.com.pk/search?q=antibodies&source=lnms&tbm=isc h&sa=X&ei=UhekUpHDIoKShgeBYG4Cg&ved=0CAcQ_AUoAQ&biw=1024&bih=629#imgdii=_ Each type of antibody is unique and defends the body against one specific type of antigen Fig 9.2 Glick 2nd Ed / Glick 3rd Ed (Two Fab and one Fc) composes ~75 % of the immunoglobulins in human serum An Fc receptor is a protein found on the surface of certain cells including • B lymphocytes • Follicular dendritic cells • Natural killer cells • Macrophages • Neutrophils and • Mast cells • that contribute to the protective functions of the immune system • Its name is derived from its binding specificity for a part of an antibody known as the Fc (Fragment, crystallizable region) • Fc receptors bind to antibodies that are attached to infected cells or invading pathogens • Their activity stimulates phagocytic or cytotoxic cells to destroy microbes or infected cells by antibody-mediated phagocytosis or antibody-dependent cell mediated cytotoxicity Figs down loaded from website The main feature of ADCC enhanced antibody technology POTELLIGENT®, originally developed by Kyowa Hakko Kirin, is its ability to remarkably increase the ADCC activity by reducing the amount of the fucose in the carbohydrate structure of antibodies, thus causing the extremely effective elimination of target cells, such as cancer cells Good Manufacturing Practice Antibody Production and Functions: • Antigens stimulate an immune response via the production of antibodies • When a pathogen invades the body, it is engulfed by wandering macrophages which present the antigenic fragments on its surface • This macrophage becomes an antigen-presenting cell, and presents the antigen to helper T cells (TH cells) • The TH cells bind to the antigen and become activated, and in turn activate the B cell with the specific antibody for the antigen • This B cell clones and differentiates into plasma cells and memory cells • The plasma cells produce high quantities of specific antibody to the antigen, whereas memory cells survive in the bloodstream for years • Upon re-exposure to the antigen, memory cells initiate a faster and stronger response and thus confer long-term immunity Fig down loaded from Google/Antibodies/Images Antibody Production in vivo: MHC - major histocompatibility complex Antibodies Functions: Polyclonal Antibodies Production: (Hybridoma Technology) (HGPRT+) (HGPRT- ) The accumulation of fluid in the peritoneal cavity, causing abdominal swelling Antibodies (Polyclonal/Monoclonal) Uses in Basic and Applied Sciences: • Antibodies have a wide variety of uses. For example: To immuno-localize a particular antigen in a tissue immunohistochemistry o Tissue can be fixed and incubated with the antibodies of interest o These antibodies can then be localized using a 'secondary' antibody coupled to a gold particle or another enzyme or radioactive label o That gives a chemical reaction like horse radish peroxidase or beta galactosidase o A secondary antibody is frequently made by generating an immune response to the Fc region of the primary antibody in another species o Thus, if the primary antibody is a mouse IgG o then the secondary could be a rabbit anti-mouse antibody which has been linked to β-galactosidase o Alternatively the antibody can be purified and then conjugated to another molecule to produce a fluorescent antibody to quantitate the presence of an antigen using either a radioimmunoassay (RIA) or an enzyme linked immuno-absorbent assay (ELISA) to detect a protein after fractionation by SDS-PAGE – a technique called Western blotting to selectively bind to and precipitate an antigen – a technique called immuno-precipitation to purify - a technique called affinity chromatography To diagnose and to treat various diseased conditions like cancer Figs down loaded from Google/Antibodies/Images iii. Glycosylation: It is a process by which sugars/glycans are chemically attached to proteins to form glycoproteins It is a form of co-translational and post translational modification Five classes of glycans are produced: • N-linked glycans attached to a nitrogen of asparagine or arginine sidechains Secondary antibody linked with enzyme (conjugated secondary antibodies) Primary antibody linked with enzyme Primary antibody Secondary antibodies amplify the signal out put Western Blotting Human Epidermal Growth Factor Receptor 2 (HER2/neu) CD - cluster of differentiation CDC - Complement-dependent cytotoxicity ADCC - Antibody-dependent cellular cytotoxicity Figure 1. Elimination of tumor cells decorated with an ab-derived therapeutic protein via the recruitment of effector cells. Depending on the type of effector cell and the chosen trigger molecule, the mode of action can be either antibody dependent cellular cytotoxicity (ADCC), antibody dependent cellular phagocytosis (ADCP), or a cytotoxic T-cell reaction. The depicted cytotoxic agents are a monoclonal ab, a bispecific chemically coupled F(ab)2, a recombinant bispecific tandem single-chain Fv-fragment (bsscFv), and a trispecific tandem single chain triplebody (sctb). Antibodies 2012, 1(1), 88-123; doi:10.3390/antib1010088 Antibody-drug conjugates or ADCs are a new class of highly potent biopharmaceutical drugs designed as a targeted therapy for the treatment of people with cancer Structure of divalent (top) and trivalent (bottom) scFvs, tandem (left) and di/trimerisation format (right). Divalent (or bivalent) single-chain variable fragments (di-scFvs, bi-scFvs) can be engineered by linking two scFvs. Figure 3. Schematic structure of NK-cell recruiting agents. (A) tandem bispecific single chain Fragment variable (bsscFv); (B) single chain triplebody (sctb); (C) two-chain diabody; (D) tandem diabody (TandAb); (E) bispecific Tribody (bsTb); (F) bispecific Bibody (bsBb); (G) dual-affinity re-targeting molecule (DART); (H) mini-ab; (I) immunoligand; Antibodies 2012, 1(1), 88-123; doi:10.3390/antib1010088 • O-linked glycans attached to the hydroxy oxygen of serine, threonine, tyrosine, hydroxylysine or hydroxyproline side-chains Fig down loaded from Google/glycolsylation/Images Asparagine / Glutamine Serine / threonine Antibodies User Survey R and D