Antibody production Immunity and vaccination Monoclonal antibodies Blood clotting

1. Antibody productionImmunity and vaccinationMonoclonal antibodiesBlood clotting IB2 Biology Jin Young

2. Stages in Antibody Production • Antigen presentation • Activation of helper T-cells • Activation of B-cells • Production of plasma cells • Production of memory cells

3. Stage 1: Antigen presentation • Macrophages take in antigens • Attach to MHC proteins • Move to the plasma membrane • Antigens displayed on the surface

4. Stage 2: Activation of helper T-cells • Receptors with same antigen-binding domain • Helper T-cell binds to macrophage • Macrophage activates T-cell

5. Stage 3: Activation of B-cells • Inactive B-cells with antibodies in plasma membrane • When they match an antigen, they bind • Activated helper T-cell bind to B-cell • B-cell is activated

6. Stage 4: Production of plasma cells • Activated B-cells go through mitosis • Cloning • Become active • Develop plasma cells (cytoplasm) • Synthesis of large amounts of antibody

7. Stage 5: Production of memory cells • T-cells and B-cells • Remain and rapidly respond • Give long-term immunity • Animation http://highered.mcgraw-hill.com/sites/0072943696/student_view0/chapter14/animation__t-cell_dependent_antigens__quiz_1_.html

8. Active and passive immunity • Active immunity: antibodies by the organism itself • Passive immunity: antibodies received from another organism • During pregnancy antibodies passed to the fetus

9. Vaccination • Vaccine • Weakened forms • Killed forms • Chemicals produced by the microorganism • Booster shot • Stimulate production of enough antibodies

10. Benefits Epidemics and pandemics prevented Deaths prevented Disability prevented Reduce health care costs Dangers Adverse reactions Severe allergic reactions (anaphylaxis) Fever Pain Swelling redness Vaccination (contd.)

11. Principles of antibody production • Clonal selection • > 1015 antibodies • B-cells clone themselves • Challenge and response • Immunity developed only when disease challenges the immune system

12. Production of monoclonal antibodies • Antigens injected to an animal • B-cells extracted from the animal • Tumour cells obtained • B-cells fused with tumourcells • Hybridoma cells- produceantibody • Antibodies are extracted and purified http://highered.mcgraw-hill.com/olc/dl/120110/micro43.swf

13. Blood clotting • Blood clot: semi-solid from blood • Seal up the wound • Prevent pathogens entering • Platelets: small cell fragments that circulate in blood plasma

14. Clotting • Release of clotting factors • Damaged tissues • Plasma • Set off a series of reactions • In the last reaction, soluble plasma is altered • Long proten fibres, fibrin • Fibrin forms a mesh of fibres, incld. blood cells • Form semi-solid clot • Dries when exposed to air

15. Antigens: foreign proteins that trigger an immune response Antibodies: protein molecules that we produce in response to a specific type of pathogen Macrophage: a type of leucocyte that gets involved very early in the process of fighting off a pathogen Fibrin: fibrous protein which forms a mesh-like network that helps to stabilize the platelet plug Active immunity: the organism produces antibodies on its own; always leads to the production of memory cells and thus provides a long-term immunity to a pathogen Passive immunity: when one organism acquires antibodies which were produced in another organism Vocab