Cytokines Flashcards
Chemical messengers that regulate the immune system
Cytokines
Single cytokine can have many different actions
Pleiotropy
Different cytokines activate some of the same pathways and genes
Redundancy
Effect of cytokines complement and enhance each other
Synergistic
Cytokine secreted by a specific type of cell can activate target cells to produce additional cytokines
Cascade induction
Main cytokines involved in innate immune response
IL-1, TNF-a, IL-6, chemokines, transforming growth factor-B, IFN-a & B
IL-1a & B are produced by:
Monocytes, macrophages, dendritic cells
Functions as the thermostat for the body
Hypothalamus
Acts as an endogenous pyrogen (induces fever) in the acute-phase response
IL-1
IL-1 induces production of ____.
Vascular cell-adhesion molecules
Chemokines
IL-6
Passage of leukocytes through the walls of the blood vessels
Diapedesis
Best characterized cytokine inhibitor
IL-1RA
Cytokine which causes vasodilation and increased permeability
TNF-a
Main trigger for TNF-a
Presence of lipopolysaccharide from gram(-) bacteria
Primary mediator of TNF-a signal transduction
TNFR1
TRUE or FALSE: TNF-a and IL-1 are present in rheumatoid synovial fluids and synovial membrane of patients with RA.
True
IL-6 is produced by:
Lymphoid and non-lymphoid cell types
____ triggers IL-6 secretion.
IL-1
Stimulates B cells to proliferate and differentiate into plasma cells
IL-6
Induces CD4+ T cells to produce greater quantities of pro- & anti-inflammatory cytokines
IL-6
Common signal-transducing receptor subunit used by cytokines
gp130
Family of cytokines that enhance motility and promote migration of WBCs
Chemokines
Cell adhesion molecules on leukocytes
Integrins
Chemokine receptors used by HIV as coreceptors for infection of CD4+ T lymphocytes & macrophages
CXCR4 & CCR5
Induces antiproliferative activity; acts as a control to help downregulate inflammatory response when no longer needed
TGF-B
Important factor in the establishment of oral tolerance to bacteria
TGF-B
IFNs are produced by:
Dendritic cells
Induce production of proteins and pathways that directly interfere with viral replication and cell division
IFN-a & B (type I IFNs)
TRUE or FALSE: Type I IFN does not activate NK cells.
False
IFN which is efficacious in treating multiple sclerosis
IFN-B
IFN used to treat hepatitis C and Kaposi’s sarcoma
IFN-a
Activation of ____ cells induces high-level expression of IFN-gamma.
Th1
____ increases the cytolytic ability of NK cells.
IL-12
____ is the principal molecule produced by Th1 cells.
IFN-Y
Most potent activator of macrophages
IFN-Y
Also known as the T-cell growth factor
IL-2
Induces production of MHC-I, IL-4, IL-5, IL-13, and CD80 and CD86
IL-4
Plays an anti-inflammatory role by inhibiting activation and cytokine secretion by monocytes
IL-13
Has an anti-inflammatory and suppressive effects on Th1 cells
IL-10
Serves as an antagonist to IFN-Y
IL-10
TGF-B induces expression of ____, a transcription factor that causes Treg cells to suppress the activity of other T cells.
Foxp3
CD4+ T cells induced from antigen-activated naive T cells in the presence of IL-10
Adaptive T regulatory (Tr1) cells
Play an important role in host defense against bacterial ad fungal infections at mucosal surfaces
Th17 cells
Primary mediators of hematopoiesis
Colony stimulating factors (CSFs)
Acts to drive differentiation toward other WBC types
GM-CSF
If ____ is activated, the cells become macrophages.
M-CSF
If ____ is activated, the cells become neutrophils.
G-CSF
Regulates RBC production in the bone marrow; produced by the kidneys
Erythropoietin
EPO levels should be interpreted with ____ because levels ca increase up to a thousand-fold during anemia.
Hematocrit
