Topic 11.1: Antibody Production and Vaccination
Specific Immunity Innate Immunity: Immunity present at birth Adaptive Immunity: immunity developed during life Specific immunity comes in to play when a pathogen has breached the first and second line of defense 1st line (skin, mucous membranes, acid) 2nd line (phagocytes, inflammatory response, interferons, complement system)
Identification MHC Body cells recognized as self Invading pathogens are recognized as non self MHC: major histocompatibility complex Group of cell surface molecular protein markers Found on surface of all nucleated cells (except RBC’s) Unique to each individual (except identical twins) 2 types Located on immune cells Located on nucleated body cells
Lymphocyte Review B-cells T-cells Originate and fully mature in bone marrow Destroy any free pathogen (not inside a cell) T-cells Originate in bone marrow but mature in the thymus Destroy any body cells infected with pathogens and cancerous cells
Cell-Mediated and Humoral Immunity Feature Humoral immunity Cell-mediate immunity Lymphocytes involved B-cells T-Cells Effector cells Plasma cells Cytotoxic T-Cells Target/function Destroys all free antigens (not inside of cells) Destroys all infected cells, multicellular pathogens and cancerous cells Mode of action Plasma cells produce antibodies that surround and neutralize the pathogen Cytotoxic T-cells release chemicals that trigger apoptosis of the infected cell
Clonal Selection Activated B cells multiply to form a clone of plasma cells and memory cells Large number of plasma cells that produce one specific antibody
Cell-mediated response initiated at same time as humoral response Activation of humoral response triggers existing B-cells to give rise to effector cells (plasma cells) and memory cells Plasma cells develop from activated B-cells and produce antibodies Cell-mediated response initiated at same time as humoral response Activates cytotoxic T-cells and memory cells
Humoral & Cell mediated immunity
The Role of Antibodies Opsonization: make pathogens more recognizable to phagocytes Neutralization of viruses and bacteria Neutralization of toxins Activation of complement (causes cell to lyse) Agglutination (sticking together)
Review of Immune response Challenge: body is invaded by pathogens Response: Helper T-cells are alerted to the presence of a pathogen. Clonal selection: Only those B-cells and T-cells that are specific to the antigen are activated Memory cells: produced to be ready to destroy any subsequent invasion by the same pathogen
Active & Passive Immunity Type Response Active natural immunity Naturally obtaining the antigen from the environment (saliva) Active artificial immunity Organism artificially obtaining the antigen from the environment(vaccination) Passive natural immunity Results from receiving antibodies du to natural processes (breastfeeding) Passive artificial immunity Receiving antibodies due to artificial antibodies (injections of antibodies)
Antibodies Antibodies (immunoglobins) Are Y shaped Globular proteins Produced by plasma cells Destroy antigens by surrounding them
Monoclonal antibody production Uses biotechnology Mass production of an antibody specific to any desired antigen Steps Antibody injected into a rodent with selected antigen Spleen removed B-cells removed from spleen B-cells fused with cancer cells to produce hybridomas Hybridomas divide indefinitely and produce antibodies Hybridomas can be used for diagnosis and treatment
Monoclonal Diagnostic use Treatment use Detection of HIV antibodies Detection of cardiac enzymes (signal heart attack) HCG pregnancy Treatment use Targeting cancer cells with chemo Emergency treatments of rabies Tissue typing for transplant compatibility
The Principle of Vaccination The goal of a vaccine is to trigger a primary immune response that results in the production of memory cells Weakened form of the pathogen is injected or inhaled Allows immune system to recognize and destroy antigen Normal response 5-10 days Vaccine response 3-5 days
Primary and secondary antibody production
Benefits & Dangers of Vaccines Eliminate disease (smallpox) Prevent serious side effects Less medical costs Prevent pandemics and epidemics Dangers Allergic reactions Injection site could become infected Rare cases of neurological issues
Allergies When immune system response with an exaggerated immune response to harmless antigens Food pollen Release of histamines (trigger) Constriction of smooth muscle (breathing problems) Increasing permeability of capillaries (swelling)