Q: What are general properties of cytokines? A: (1) short half-life (2) modulate the immune response (3) produced by/ modulate many types of cells (4) redundant (5) affect other cytokines (6) recognized by specific receptors Q: What are the cytokines that influence the innate immune system? A: (1) interferon alpha/beta (type one interferon) (2) TNF (3) IL-1 (4) IL-6 (5) Chemokines Q: What cells make INF-alpha and INF-beta (alpha and beta are the type one interferons)? A: INF-alpha made by monocytes and macrophages mostly. INF-beta made by all cells Q: What kind of response do the type I interferones (alpha and beta) cause? A: Anti-viral response. Specifically they (1) upregulate Class I MHC and decrease class II MHC and (2) induce enzymes preventing virus replication (make the cell anti-viral) Q: How is TNF induces and what cells does it come from? A: LPS- activation of macrophages by bacterial infection. TNF is present in granules of mast cells (preformed). Q: Once TNF is released by a cell, it basically elicits one response in the body. T or F A: False TNF can elicit two general responses depending on the quantity of TNF released. Localized signaling for low quantities and systemic for higher concentration. Q: What response is generated from low quantity TNF release? A: (1) increase adhesion molecules on endothelium (2) up regulates killing efficiency of neutrophiles and eosinophils. (3) Increase class I MHC expression (4) induce other cells to produce cytokines. Q: What response is generated from high quantity TNF release? A: (1) induces fever as an endogenous pyrogen (2) induces cells to produce IL-1 and IL-6 (3) Increases phagocytosis by increasing acute phase protein production by liver (4) suppresses bone marrow cells from dividing Q: What stimulates IL-1 production and what does IL-1 do? A: Macrophages/monocytes produce IL-1 after TNF, LPS, or IL-1 induction. IL-1 basically does the same functions as TNF. (local inflamm, fever, acute phase proteins etc) Q: What stimulates IL-6 and what are it's functions? A: IL-6 if activated by IL-1 and TNF. It's functions are similar and it also acts to polyclonally activate Be cell differentiation. Q: What are the cytokines that regulate lymphocyte activation and differentiation? A: IL-2; IL-4; TGF-beta; INF-gamma; IL-10; IL-12 (all discussed individually) Q: What cytokine induces a TH1 T-cell and what does this helper cell do? A: IL-12 and IFN-gamma. TH1 cells (1) activate macrophages (2) Induce more T cells (TH1) (3) increase MHC expression on APC's (4) Induce B cells to release opsonins (help macrophages). Q: What cytokine induces TH2 T-cells and what does this helper cell do? A: IL-2 and IL-4; TH2 cells (1) inhibit macrophage activation (2) induce more T cells (TH2) (3) Induce B cells to produce IgE and IgG4. Q: What makes IL-2 and what are its actions? A: Made by most helper T-cells upon activation. It is a T-cell growth factor. (2) it can also act on NK cells increasing killing capacity. Q: What makes IL-4 and what are its functions? A: Product of TH2 T cells and sometimes mast cells. (1) Induce production of IgE (2) block macrophages (anti-iflammatory) (3) mast cell growth factor (4) stim. Expression of adhesion receptors. Q: What does TGF-beta do? A: suppresses the effect of other cytokines (anti-inflammatory) Q: What produces INF-gamma and what is its function? A: Prod. by TH1 T-cells. (1) anti-viral and anti-proliferative (2) activates macrophages (3) upregulate NK and neutrophil function (4) shifts TH0 cells to TH1 upon activation Q: What makes IL-10 and what are its functions? A: Mad eby TH2 cells and mast cells in mucosa. (1) opposite of IFN-gamma (2) inhibits cytokine trascription in macrophages (3) reduces Class II MHC and B7 on macrophages (can't activate T-cells) Q: What makes IL-12 and what are its functions? A: B- cells and monocytes. The receptor is express by NK and T-cells. (TNF-alpha induces IL-12 prod. by macrophages. (1) activates NK (2) commits TH0 to TH1 pathway (3) increases activity/proliferation of CD8 T cells. Q: What are the cytokines called that influence the development of cells in bone marrow and what are examples? A: Colony stimulating factors (growth factors). IL-3, GM-CSF, Macrophage colony stimulating factor, Granulocyte CSF, and IL-7 Q: What is the function of IL-7? A: B cell/ T cell growth factor Q: What does IL-3 do? A: Broad activator of bone marrow expansion: prolonged exposure produces mast cells Q: What does GM-CSF do? A: Granulocyte-Monocyte colony stimulating factor (it activates them). Q: What does granulocyte CSF do? A: push cells to granulocyte lineage: neturophil and eosinophils (CSF=colony stimulating factor)