Cytokines and Chemokines-Monika Flashcards
TNF
enhances NADPH oxidase activity
activates inducible nitric oxide synthase
IL-2
Growth factor for T cells
enhances NK cell cytotoxicity
role in pCTL to CTL differentiation
IL-3
Hematopoiesis (imp. for myeloid & lymphoid progenitor cell development)
IL-4
Required to isotype switch to IgE
Down regulation of Th1 cytokine production
Down regulation of iNOS (not as effective as TGFbeta)
IL-5
Hematopoeisis- differentiation of eosinophils
Chemotactic for eosinophils (recruiting to tissues)
activates eosinophils
IL-6
stimulates secretion of C-reactive protein from hepatocytes (inflammation)
if TGF present, role in Thp –>Th17 differentiation
IL-7
hematopoiesis- B and T cell differentiation (bone marrow and thymus)
IL-10
Down regulates IL-12 secretion by dendritic cells & macrophages (down regulation of Th1 Cytokines)
Down Regulates iNOS (TGF beta more effective)
inhibitory molecule
IL-12
Activates NK cells to secrete IFNgamma (enhanced if IL-15 or IL-18 present)
IL-13
In lung - mediates allergic asthma
role in helminth infections (nematodes- round worms)
IL-15
(with IL-12) helps to induce NK to secret IFN
IL1 and TNF (synergistic)
- inflammatory role
- (+) macrophages to secrete CK (IL1, 6, 12, TNF) & chemokines ( IL-8 & MCP-1)
- (+) endothelial cells–> (de novo expression of ICAM-1, VCAM-1, E-selectin) + enhanced ICAM-2 expression.
(+) endothelial cells –> secrete chemokines IL-8 AND MCP-1
4. act on hypothalamus–>fever, lower BP –> shock
IL-17
induces expression of proinflammatory cytokines and chemokines from wide range of cells (IL-6, IL-8, GM-CSF, G-CSF & metalloproteinases from macrophages
and other cell types)
Autoimmune disorders - if Th17 cells specific for self antigen
Chemotactic for neutrophils
Role in fungal and extracellular bacterial infections
IL-18
(with IL-12) helps to induce NK cells to secrete IFN
IL-21
Growth factor (amplification) of Th17 cells
IL-22
Proinflammatory -
elevated in inflammatory conditions (rheumatoid arthritis, psoriasis)
IL-23
Differentiation of Thp cells to Th17 cells in the presence of TGF & IL-6 or IL-1
Proinflammatory with 2 subunits: p19 and p40. (p40 = common to IL-12 and IL-23)
Elevated in multiple sclerosis, psoriasis, Crohn’s disease
IL-33
Activates mast cells
Upregulated in intestinal parasite infection
Receptors found on Th2 cells
Alarmins = molecules released upon necrosis; released by some immune cells without undergoing necrosis.
-IL-33 released when endothelial/epithelial cells undergo damage/necrosis –> triggers immunological processes following trauma/infection (e.g. mast cell activation)
Dysregulated IL-33 –> asthma, arthritis, inflammatory bowel disorder
IFN-gamma
Activates iNOS
Enhances activation of NADPH oxidase
Down regulates production of Th2 cytokines
Critical for Th0 differentiation to Th1 phenotype
(with IL-2) Promotes pCTL to CTL differentiation
Enhances expression of Class I MHC on nucleated cells
Enhances expression of Class II MHC on antigen presenting cells
IFN-alpha and IFN-beta
Triggers production of enzymes (e.g. 2’5’oligoadenylate synthetase) that interfere with replication of some viruses
Inhibits T cell proliferation
Increases expression of Class I MHC on nucleated cells
TGF-beta
Down regulation of iNOS
Differentiation of Th0 cells to a/i Tregs
In the presence of IL-6 or IL1 and IL-23 –> differentiation of Thp cells to Th17
Colony Stimulating Factor: GM-CSF
Hematopoiesis
Differentiation of myeloid progenitor to GM-progenitor
Mobilization and activation of dendritic cells
Colony Stimulating Factor: G-CSF
Hematopoiesis
Differentiation of GM progenitor to granulocyte/neutrophil
Colony Stimulating Factor: M-CSF
Hematopoiesis
Differentiation of GM progenitor to monocyte
