Cytokines Flashcards
1) produced by CD4+ T cells
2) paracrine and autocrine growth factor for T cells
3) increases NK cell cytotoxicity and (at high conc.) induces NK cells to become lymphokine- activated killer (LAK) cells
* **growth factor for Treg cells
IL-2
suppressive cytokine produced and secreted by Treg cells:
1) inhibits DCs and macrophages from producing IL-12
2) down regulates expression of co-stimulatory molecules and class II MHC
IL-10
activates Th1
IL-12
1) produced by activated T cells and activated macrophages
2) induces Th17 cells
3) inhibits T cell proliferation/differentiation into CTL’s
4) inhibits macrophage activation
5) induces B cells to produce IgA at mucosal sites
6) initiates wound healing –> fibroblast migration/ proliferation and increased collagen synthesis
TGF-beta
What cytokine category is produced by macrophages and it regulates phagocytic cells?
monokines
What cytokine category is produced by activated T cells and it regulates lymphocytes, macrophages, neutrophils, eosinophils?
lymphokines
What cytokine category is produced by lymphocytes, macrophages, BM stromal cells?
colony-stimulating factors
What are the three cytokine activities?
1) autocrine (self)
2) paracrine (local vicinity)
3) endocrine (long distance)
1) upregulate expression of MHC class I
2) activate NK cells
3) block viral replication
Type 1 interferons (IFN-alpha and IFN-beta)
produced by mononuclear phagocytes and T lymphocytes in response to bacterial LPS
TNF-alpha (tumor necrosis factor)
What are the five biological actions of TNF-alpha?
1) activates macrophages/neutrophiles
2) increase adhesiveness of vascular endothelium for neutrophils
3) fever generation
4) neutrophilia
5) DIC (coagulation)/shock
1) produced by CD4+ T cells, mast cells, basophils –> induces B cell isotype switching to IgE
2) activates Th2 immune response
3) inhibits Th1 immune resposne
IL-4
1) Type 2 IFN
2) mainly produced by CD4+ and CD8+ T cells and NK cells
3) directs immune response toward cell-mediated immunity
4) most potent activator of macrophages
5) upregulates class I and class II MHC expression
6) isotype switching to IgG
IFN-gamma
activates Th17 (3)
IL-1
IL-6
TGF-beta
Th2 releases these cytokines after activation
IL-4
IL-5
IL-13
