CH 15 - immune system Flashcards
(77 cards)
What are the 2 types of immune systems?
Innate (nonspecific) immunity
Adaptive (specific) immunity
What are the 3 main parts of the innate immune system?
Physical barriers (skin/mucous membranes)
High acidity (stomach/fevers)
Antimicrobial peptides and interferon (wbc)
What is activation of innate immunity?
Cells distinguish “self” from “nonself” using pathogen-associated molecular patterns (PAMPs) unique to the pathogens.
What are lipopolysaccharides found in/used for?
found in the envelop of Gram-negative bacteria
What are peptidoglycans found in/used for?
The cell walls of Gram-positive bacteria
How does innate immunity work?
Secrete chemokines to recruit more immune cells
Secrete cytokines to promote aspects of innate and adaptive responses
What is:
~ Located in the cytoplasm
~ Used to recognize intracellular molecules from bacteria
~ Activate the production of cytokines
~ Can lead to programmed cell death of infected cells
NOD-like receptors
What is the job, make, and promotion of the complement system?
Integrates innate and adaptive immune responses.
Consists of proteins in the plasma and other body fluids that become activated when antibodies bind to antigens.
Complement proteins promote phagocytosis, lysis of target cells, and local inflammation.
In innate immunity, what are the 3 signs of local inflammation with no infection?
Tissue damage occurs that causes necrosis.
Immune system exposed to DAMPs – danger-associated molecular patterns, after cell injury.
Stimulates innate immune responses and inflammation.
What is the job of toll-like receptors?
Only let in recognizable pathogens
What are the types of phagocytic cells?
Neutrophils
Mononuclear phagocytic cells
When does neutrophils arrive (and to where)?
The first to arrive at an infection.
When does mononuclear phagocytic cells arrive (and to where)?
(monocytes in the blood and macrophages and dendritic cells in the tissues) arrive after the neutrophils
What are the 6 steps of phagocytosis in tissues?
Neutrophils and monocytes undergo extravasation (diapedeses): squeeze through gaps in post-capillary venule walls to enter tissue
Brought to the site from chemotaxis by cytokines/chemokines
The pathogen becomes engulfed by pseudopods.
The vacuole containing the pathogen fuses with a lysosome.
The pathogen is digested.
Lysosomal enzymes may be released before fusion is complete, killing the cell, and contributing to local inflammation.
What regulates/produces fever?
Regulated by the preoptic area of the hypothalamus that acts as a thermostat.
Prostaglandin (PGE2) acts as a paracrine regulator to produce fever.
Why is too high of a fever bad?
Fall in plasma iron concentration.
Inhibits bacterial activity.
Increased activity of neutrophils and more interferon production.
What are interferons?
Antiviral polypeptides produced by infected cells that cause non-specific, short-term resistance to viral infection
What is adaptive immunity?
The acquired ability to defend against specific pathogens after exposure to these pathogens
Read me :D
(do it and mark this as a 3 or 4)
Relax your posture
Take a deep breath
Unclench your jaw
Go drink water
You got this!
What are antigens and what are their jobs?
Foreign antigens illicit an immune response. The immune system can distinguish “self” from “nonself.” (bad)
What are T-Lymphocytes?
Lymphocytes that seed the thymus become T lymphocytes.
These then seed the blood, lymph nodes, and spleen.
T lymph. attack host cells that are infected with a virus or fungus (and cancer)
What is cell-mediated immunity?
T-lymphocytes which must be in close proximity to the victim cell in order to destroy it.
What are B-Lymphocytes?
Lymphocytes that come directly from bone marrow to seed other organs (not the thymus) are called B lymphocytes.
They combat bacterial and some viral infections.
What is humoral immunity or antibody-mediated immunity?
B-lymphocytes which secrete antibodies into blood and lymph so can be far from the infection.