Lecture 2: Biotechnology PDF

Lecture 2 By: Dr. Amal Uzrail  © 2013 Pearson Education, Inc. FLOWCYTOMETRY  © 2013 Pearson Education, Inc. Select this paragraph to edit  © 2013 Pearson Education, Inc. Select this paragraph to edit ...

Lecture 2 By: Dr. Amal Uzrail  © 2013 Pearson Education, Inc. FLOWCYTOMETRY  © 2013 Pearson Education, Inc. Select this paragraph to edit  © 2013 Pearson Education, Inc. Select this paragraph to edit  © 2013 Pearson Education, Inc. Select this paragraph to edit  © 2013 Pearson Education, Inc. Select this paragraph to edit  © 2013 Pearson Education, Inc. Select this paragraph to edit  © 2013 Pearson Education, Inc. Select this paragraph to edit  © 2013 Pearson Education, Inc. Select this paragraph to edit  © 2013 Pearson Education, Inc. Select this paragraph to edit ANTIBODIES USE IN IMMUNO- DETECTION METHODS  Immuno blot (western blot)  Immunofluorescence  Screening of DNA libraries © 2013 Pearson Education, Inc. Western blot The western blot (sometimes called the protein immunoblot) is a widely accepted analytical technique in molecular biology used to detect specific proteins in the given sample. Used for the detection of HIV Western blot Western blot © 2013 Pearson Education, Inc. Western blot IMMUNOFLOURESCENCE Select this paragraph to edit © 2013 Pearson Education, Inc.  © 2013 Pearson Education, Inc. Select this paragraph to edit  © 2013 Pearson Education, Inc. SCREENING DNA LIBRARIES © 2013 Pearson Education, Inc. Haptens Why Haptens are not Immunogenic?  Haptens can induce immune response when covalently bound to a large protein called a ‘carrier protein’ forming Immunogenic Hapten-Carrier Conjugate. Carrier protein molecule are antigenic as well as immunogenic. A peptide of the carrier protein is presented in association with class II MHC protein to the helper T cells. The activated helper T cells then produce interleukins, which stimulates the B cells  Do not activate B-cells Carrier Protein Activate B- cells  By itself, a hapten cannot function as an immunogenic epitope. But when multiple molecules of a single hapten are coupled to a carrier protein (or nonimmunogenic homopolymer), the hapten becomes accessible to the immune system and can function as an immunogen.  © 2013 Pearson Education, Inc. Select this paragraph to edit  injected Anti-serum Hapten molecule injected Anti-serum Carrier Molecule injected Anti-serum Hapten-Carrier Conjugate  © 2013 Pearson Education, Inc. Select this paragraph to edit  The formation of drug-protein conjugates in the body can produce drug allergies that may be life-threatening. Immunologist’s favorite, as it can be used as-  DIAGNOSTIC TOOL:  To evaluate the properties of specific epitopes and antibodies.  They are important in the purification and production of monoclonal antibodies.  Enzyme-multiplies Immunoassay Technique (EMIT): They are also vital in the development of sensitive quantitative and qualitative immunoassays  ALLERGY TO DRUGS Other drugs which may elicit allergy streptomycin, aspirin, the so- called “sulfa-drugs” such as the sulfonamides, some anaesthetics (e.g., succinyl choline), and some opiates. Application of Haptens in Pregnancy test INTRODUCTION  A vaccine is a biological preparation that establishes or improves immunity to a particular disease.  The term vaccine derives from Edward Jenner's 1796 use of the term cow pox, which, when administered to humans, provided them protection against smallpox. VACCINE DESIGN AND PRODUCTION  The vaccines that prevent small pox and other diseases are based on the use of either killed or live micro- organisms.  When vaccinated with such a non-virulent microbe, your body produces antibodies to that organism, but you don’t get the disease. VACCINE DESIGN AND PRODUCTION  If you are exposed to that microbe again, your body has a ready supply of antibodies to defend itself. PROBLEMS WITH VACCINES 1) Generally vaccines cause no serious problems, but they do have side effects, like :  Allergic reactions  Aches or pains  Fever PROBLEMS WITH VACCINES  2) A second problem with this method of vaccination is consistent production of virus based vaccines.  3) Developing vaccinations for some deadly infectious diseases, such as HIV/AIDS and malaria is risky VACCINE PRODUCTION  Usually, only one or a few proteins on the surface of pathogen trigger the production of antibodies.  By isolating the gene and inserting into E. coli, large quantity of proteins can be produced to serve as vaccine. VACCINE PRODUCTION  When protein is injected the body produces antibodies that can recognize the pathogen.  Using these new techniques of biotechnology, scientists have developed vaccines against diseases such as Hepatitis B and Meningitis. DNA VACCINES  Injecting naked DNA into muscles or skin cells also elicits immune response.  Researchers had assumed that DNA alone would not trigger an immune response of sufficient strength to impart protection against infectious diseases. VACCINE DELIVERY SYSTEMS  Vaccine being developed is a Live Virus, a coat protein or a piece of its DNA, the production of vaccines require costly facilities and procedures.