Important Cytokines Flashcards
Interleukin-1
IL-1
Secreted by macrophages
An endogenous pyrogen, also called osteoclast-activating factor.
Causes fever, acute inflammation.
Activates endothelium to express adhesion molecules;
Induces chemokine secretion to recruit leukocytes
Interleukin-6
IL-6
Secreted by macrophages and Th2 Cells
Endogenous pyrogen
Causes fever
Stimulates production of acute-phase proteins
Interleukin-8
IL-8
Secreted by macrophages
Major chemotactic factor for neutrophils
“Clean up on aisle 8”
=> Neutrophils are recruited by IL-8 to clear infections
Interleukin-12
IL-12
Secreted by macrophages and B cells
Induces differentiation of T cells into Th1 Cells
Activates NK cells
Tumor Necrosis Factor-alpha
TNF-alpha
Secreted by macrophages
Mediates septic shock
Activates endothelium
Causes leukocyte recruitment and vascular leak
Interleukin-2
IL-2
Secreted by all T cells
Stimulates growth of helper, cytotoxic, and regulatory T cells
“T cell stimulator”
Interleukin-3
IL-3
Secreted by all T cells
Supports the growth and differentiation of bone marrow stem cells.
Functions like GM-CSF
Interferon-gamma
IFN-gamma
Secreted by Th1 cells
Has antiviral and antitumor properties.
Activates NK cells to kill virus-infected cells
Increases MHC expression
Increases antigen presentation in all cells
“Macrophage stimulator”
Interleukin-4
IL-4
Secreted by Th2 cells
Induces differentiation into Th2 cells
Promotes growth of B cells
Enhances class switching to IgE and IgG
“B cell stimulator”
Interleukin-5
IL-5
Secreted by Th2 cells
Promotes differentiation of B cells
Enhances class switching to IgA
Stimulates the growth and differentiation of eosinophils
“B cell stimulator”
Interleukin-10
IL-10
Secreted by Th2 cells and regulatory T cells
Modulates inflammatory response
Inhibits actions of activated T cells
Inhibits actions of activated Th1 cells
Has similar actions to TGF-beta, since both are involved in inhibiting inflammation
