Antibody production Immunity and vaccination Monoclonal antibodies Blood clotting IB2 Biology Jin Young

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

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

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

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

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

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

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

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

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

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

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

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

Clotting Release of clotting factors Set off a series of reactions 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

Vocab 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