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40 Cards in this Set
- Front
- Back
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What are the two components of the immune system?
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1. Humoral immune system
2. Cell-mediated immune system |
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What are B-cells and what do they do?
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White-blood cells. When they are stimulated by antigens, they undergo further development and become plasma cells. Those plasma cells produce antibodies & those antibodies play a role in attacking and destroying antigens.
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What are some examples of antigens?
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1. Viruses
2. Bacteria 3. Dust/pollen 4. Transplanted tissue |
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How many different types of T-cells are there?
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Four.
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What is an antigen?
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Anything foreign to the body that elicits an immune response.
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What is specific immunity?
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An immunity developed in response to a challenge.
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What is acquired immunity?
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Immunity that we didn't always have.
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What is naturally acquired active immunity?
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Immunity created from adapting to exposure to antigen.
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How does our body respond to antigens (2 ways)?
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1, Producing antibody molecules that are going to be tailored to attack that antigen.
2. Producing sensitized T-cells; they are T-cells that are produced in response to a particular antigen. |
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We develop some immunity, but how long does it last?
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It varies from person to person, to antigen to antigen.
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What are examples of antigens we do not develop any durable immunity to?
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Colds, gonorrhea, pneumonia.
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What are examples of antigens we develop permanent immunity to?
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Measles, chicken pox, and yellow fever.
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What is naturally acquired passive immunity?
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This immunity occurs from a natural transfer of antibodies from an immunized donor to a non-immunized recipient?
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What are examples of naturally acquired passive immunity? How do they occur? (2 examples)
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Placental transfer. Not in all animals, but occurs in humans. Anything mom is immune to. Her Ab may cross the placental barrier to be received by the fetus. Fetus is passively receiving Ab.
Colostrum: produced 24 hours after birth; beneficial for infant to nurse because rich in Ab. Infant has porous digestive system. Ab will be absorbed directly into bloodstream. Therefore, it needs to be eaten as soon as possible. Some animals don't have placental transfer so really rely on colostrum. Short-lived immunity (8 weeks). Give newborn a chance to start to develop its own immunity. |
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What is vaccine interference?
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It occurs if you vaccinate too early. The Ab from colostrum and placental transfer will interact with the vaccine and render it ineffective.
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What is artificially acquired active immunity?
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The type of immunity we develop upon vaccination.
When you're vaccinated, your body acts the same way during naturally acquired active immunity. |
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What is artificially acquired passive immunity?
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Develops upon injection of Ab obtained from an outside source.
e.g. snake bite venom: potent, fast-acting neurotoxin; venom is a whole lot faster than immune response antivenom usually made in horses; take horse and inject with snake venom; blood is harvested from horse; blood is centrifuged in order to separate plasma with the antivenom from the serum |
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What is electrophoresis?
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A process that separates molecules based on their size and electrical charge.
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What four components do we find when we use electrophoresis on plasma?
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1. Alpha portion
2. Beta portion 3. Gamma portion 4. Albumen |
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What portion of plasma is the majority of Ab found?
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In the gamma portion.
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How can gamma-globulin be used?
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It can be given as a shot. A preventive measure.
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Describe the anatomy of a monomer antibody.
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It's Y-shaped with four main parts (2 long chains and 2 light chains).
Contains disulfide bonds. Has bended areas called hinge regions, which offers flexibility to bind to Ag. They attach themselves to Ag via Ag-binding sites. |
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How many classes/categories of Ab/Ig are there?
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Five.
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IgG
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*makes 80 to 85% of Ab in serum
*monomer antibody *found in blood, lymph fluid; relatively high concentrations in intestinal tract *migrate to other parts of the body where it is needed *also able to cross placental barrier *helps to protect against circulating bacterian viruses *helps to neutralize bacterial toxins *when IgG is bound to Ag, it enhances phagocytic cells (more aggressive) |
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What do phagocytic cells do?
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They engulf and digest foreign substances.
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IgM
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*makes 5-10% of Ab in serum
*pentamer structure - fastener called J-chain holds subunits together *"M" stands for "macro" *forms "clumps" of antigen, making it easier for immune system to clean it up *first body to show up at the site of the antigen *levels start to decline and IgG shows up next *not going to be able to cross the walls of blood vessels or the placental barrier *enhances phagocytic cells |
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IgA
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*monomer and dimer form
*makes 10-15% of Ab in serum, but IgA is found also in tears, saliva & other mucus secretions (mucus in GI tracts and breastmilk) *in serum, IgA is found in monomer form *in other secretions, found in dimer form *prevent attachment of pathogens to host tissue *it coats the surface of the pathogen and this prevents pathogen from attaching to host tissue |
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IgD
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*makes 0.2% of Ab in serum
*monomer molecule *don't know function *found in blood and lymph fluid and the surface of B-cells *it cannot cross placental barrier |
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IgE
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*makes approximately 2,000's of a percent of Ab in blood
*monomer unit but slightly larger than IgG *found attached to basophiles and mast cells - both of these cells participate in allergic reactions *stimulates the cells to release histamines |
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Where do B-cells and T-cells come from?
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Stem cells from the bone marrow.
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Maturation of T-cells
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Migrate to thymus and graduate as T-cells in blood.
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Maturation of B-cells
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Mature in the bloodstream.
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Differentiation of stem cells from the liver and the bone marrow.
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1. Processed in the thymus then migrate to lymph tissue.
2. When stimulated by Ag, they from two population of cells: 1, Effector T-cells 2. Memory T-cells 3. Most effective against bacteria and viruses that are circulating because it's easier for Ab molecules to interact with T-cells |
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What do effector T-cells do?
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Assist us with combating Ag NOW.
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What do memory T-cells do?
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Hang around to recognize Ag we've been exposed to before.
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Cytotoxic T-cells
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*Precursor to cytotoxic T-lymphocytes
*mature stage *attach to target Ag and release a protein called perforin *perforin - makes "Swiss cheese" of target antigen; pokes holes *most effective against cancerous cells, transplanted tissues, intracellular bacteria and viruses (destroys host cell). |
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CD4-positive T-cells
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*Cooperate and interact with B-cells.
*They recognize Ag on the surface of macrophages and helper T-cells activate the macrophages (makes them more aggressive) *when they get activated, go through 2-3 replication cycles *going to produce and secrete molecules called cytokines to stimulate immune system process |
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Th1
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*activate macrophages, cytotoxic T-cells, and natural killer cells
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Th2
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*other cytokines that assist in production of Ab
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Suppressor/regulatory T-cells
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*shutting down immune response once battle has been won
*another sub-set of helper T-cells *believed to help prevent rejection of fetus during pregnancy |
