The Immune System - Essential Key Terms (week 7)

Question 1

state what it is meant by the key term - acute phase proteins (ACP’s)

Answer 1

group of proteins secreted by the liver during systematic response to injury or infection (stimuli for secretion include IL-1, IL-6, and other cytokines)

Question 2

state what it is meant by the key term - antibodies

Answer 2

immunoglobulins secreted by plasma cells; bind to antigen which stimulated their production and direct an attack on the antigen or the cell bearing it

Question 3

state what it is meant by the key term - chemoattractants

Answer 3

a general name given to any chemical mediator that stimulates chemotaxis of leukocytes

Question 4

state what it is meant by the key term - chemokines

Answer 4

a chemokine is a cytokine which functions as a chemoattractant

Question 5

state what it is meant by the key term - chemotaxin

Answer 5

a chemotaxin is a synonym for a chemoattractant

Question 6

state what it is meant by the key term - complement

Answer 6

a group of plasma proteins that, upon activation, kill microbes directly and facilitate the various steps of the inflammatory process - including phagocytosis

Question 7

state the difference between the classical pathway and the alternative pathway for a complement

Answer 7

CP - triggered by an antigen-antibody complex

AP - can operate independently of an antibody

Question 8

state what it is meant by the key term - C reactive protein (C-RP)

Answer 8

one of several proteins that function as non-specific opsonins (production by the liver is increased during the acute phase response)

Question 9

state what it is meant by the key term - opsonin

Answer 9

An opsonin is any molecule that enhances phagocytosis by marking an antigen for an immune response or marking dead cells for recycling

Question 10

state what it is meant by the key term - cytokines

Answer 10

protein messengers that regulate immune responses and function both locally and as hormones

Question 11

state what it is meant by the key term - eicosanoids

Answer 11

general term for products of arachidonic acid (omega 6 fatty acid) metabolism and function as important inflammatory mediators

Question 12

state what it is meant by the key term - histamine

Answer 12

an inflammatory mediator secreted mainly by mast cells; acts on microcirculation to cause vasodilation and increase permeability to proteins

Question 13

state what it is meant by the key term - IgA

Answer 13

a class of antibodies/immunoglobulins secreted by cells lining the GI, respiratory, and Genito-urinary tracts

Question 14

state what it is meant by the key term - IgD

Answer 14

a class of antibodies/immunoglobulins who’s function is unknown

Question 15

state what it is meant by the key term - IgE

Answer 15

a class of antibodies/immunoglobulins which mediate immediate hypersensitivity and resistance to parasites

Question 16

state what it is meant by the key term - activated macrophages

Answer 16

macrophages who’s killing ability has been enhanced by cytokines (particular IL-2 and interferon gamma)

Question 17

state what it is meant by the key term - antigen presenting cell (APC)

Answer 17

a cell that presents an antigen, complexed with MHC proteins, on it’s surface to T cells

Question 18

state what it is meant by the key term - cytotoxic T cells (Tc cells)

Answer 18

the class of T lymphocytes that, upon activation by a specific antigen, directly attack the cells bearing that type of antigen

Question 19

state what it is meant by the key term - dendritic cells

Answer 19

cells that carry out phagocytosis and function as APC’s

Question 20

state what it is meant by the key term - T helper cells (Th cells)

Answer 20

the class of T cells that, via secreted cytokines, play a stimulatory role in the activation of B cells and Tc cells; can also activate NK cells and macrophages; and bind antigen associated with MHC-2 proteins

Question 21

state what it is meant by the key term - lymphocytes

Answer 21

the type of leukocyte responsible for adaptive immune responses; mainly B cells, T cells and NK cells

Question 22

state what it is meant by the key term - macrophages

Answer 22

the cell type that: 1) functions as a phagocyte, 2) processes and presents antigens to Th cells, 3) secretes cytokines involved in inflammation

Question 23

state what it is meant by the key term - mast cells

Answer 23

tissue cells that bind IgE and release inflammatory mediators in response to parasites and immediate hyper-sensitivity reactions

Question 24

state what it is meant by the key term - monocytes

Answer 24

a type of leukocyte; leaves the blood stream and is transformed into a macrophage

Question 25

state what it is meant by the key term - natural killer (NK) cell

Answer 25

class of lymphocytes that bind to cells bearing foreign antigens without specific recognition and kill them directly

Question 26

state what it is meant by the key term - neutrophils

Answer 26

leukocytes that function as phagocytes and also release chemicals involved in inflammation

Question 27

state what it is meant by the key term - plasma cells

Answer 27

cells that differentiate from activated B lymphocytes and secrete antibodies

Question 28

state what it is meant by the key term - T cells

Answer 28

lymphocytes derived from precursors that differentiate in the thymus