Flashcards in Chapter 21 - The Immune System Deck (61)
Triggered by a large number of different agents. Constitutes the first two lines of defense.
First Line of Defense
-saliva and tears
Second Line of Defense
Phagocytosis and Inflammation
Microphages which move into the tissues. Mast cells found throughout connective tissue, usually associated with allergic responses.
Monocytes which become macrophages. Found throughout connective tissue and line vascular and lymph vessels. Function to cleanse channels and form a surveillance system, the RE system.
Response of the body to any irritating agent. The overall function is to remove the source of irritation, prevent the spread of infection, and repair the damage.
4 Cardinal Signs of Inflammation
1. Heat - Calor
2. Redness - Rubor
3. Swelling - Tubor
4. Pain - Dolor
An increased blood flow to the point of injury. Dilation because of chemical substances. Mast cells and basophils release chemicals if the blood is near the surface, heat is felt and redness is notices.
Due to the accumulation of tissue fluid, swelling results in compression of the nerve endings causing pain.
Injured cells release toxins attracting phagocytic cells, they congregate at the injured site, they ingest microorganisms, dead and dying cells and other debris. The cells then die, it all accumulates forming pus.
An abscess on the outside of the body ruptures and drains outside, if it's on the inside, it ruptures and is reabsorbed by the body.
Neutrophils and other WBCs are attracted to the infection site. They pass through the vessel walls into the tissues.
Directional movement of cells in response to chemicals. Towards or away from the site.
Also called adhesion. Leukocytes are clinging to the capillary walls
Coating a microorganism to make it's surface rougher in preparation for phagocytosis
Released mainly by Mast cells, basophils, and platelets. It causes vasodilation and increased capillary permeability
Polypeptides that dilate arterioles, increase vascular permeability, act as chemotactic agents, and induce pain.
Hormones related to fatty acids, which cause vasodilation, pain, and fever
Natural Killer Cells
Large granular lymphocytes, are non-specific. They kill both tumor and virus invaded cells. They make contact with the target cell, destroying it's membrane by releasing perforins. They are the primary defenses against very early stage cancers.
A protein produced by cells that have been invaded by a virus. It doesn't protect the invaded cell, but is ingested by surrounding cells and produces an antiviral protein. 3 types alpha, beta, gamma. Also have anticancer activity.
A series of plasma proteins circulate in an inactive form. When they're activated, they become part of the specific immunity and can mediate every aspect of the inflammatory process. Non-specific activation attaches to molecules found on bacteria. It's activated by the classical, or faster pathway, or the alternative, or slower pathway.
An increase in body temperature caused by proteins called pyrogens. A protective response because many infectious organisms don't like heat. Many bacteria require large amounts of Fe and Zn, so during a fever the liver and spleen sequester those elements.
The third line of defence. This is immunity and is specifically targeted. Composed of cells and molecules which recognize and destroy the offending agent.
Humoral Mediated Immunity
Depends primarily on proteins called antibodies. They have to attack and neutralize a foreign body. This is a chemical attack.
Cell Mediated Immunity
Cells are the effectors of this type of immunity. They directly attack the foreign substance, which is always another cell. This is a cellular attack.
Substances which provoke an immune response. Are very large, and this is what the immune system responds to. It's either a protein or a complex carbohydrate.
An incomplete antigen. It's vey small. It can attach toanother cell to become antigenic.
Every lymphocyte has a unique molecure on it's membrane surface that functions as the antigen receptor. Also called epitopes. The number of receptors is called the valence number, the more on the cell, the deadlier. Each receptor is three dimensional, it will only match us with a certain antigen, it's very particular
Antigen Presenting Cell
Macrophages, B lymphocytes, and certain dendritic cells.