Term
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Definition
Cytokines are intercellular regulatory proteins produced by many different cells which ultimately control every aspect of the body defenses.
Cytokines activate and deactivate phagocytes and immune defense cells, increase or decrease the functions of the different immune defense cells, and promote or inhibit a variety of nonspecific body defenses. |
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Term
| List four different groups of cytokines |
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Definition
1. lymphokines
2. monokines
3. chemokines
4. interleukins |
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Term
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Definition
| They are low molecular weight proteins/peptides (usually < 30 kDa). |
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Term
| Does it take many cytokines for them to be effective? |
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Definition
No, cytokines are extremely potent.
They are often active in picomolar concentrations. |
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Term
| What are the three general cell signaling methods cytokines use? |
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Definition
1. autocrine- acts on itself
2. paracrine- acts on adjacent cells
3. endocrine- goes to distant parts |
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Term
| Cytokines are highly pleiotropic. What does this mean? |
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Definition
Pleiotropic- have different effects on different target cells.
Cytokines interact in complex networks. They can have multiple effects on the same cell or tissue. Effects can depend on a myriad of variables including the activation state of the cell, the number of receptors expressed, the concentration of the cytokine, and the accessory signals the cell is receiving. |
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Term
| Cytokines are pleitropic, but are also redundant. What does this mean? |
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Definition
| Two or more cytokines often have the same effect on a target cell |
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Term
| List the three ways the body copes with pleiotropy |
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Definition
1. Regulation of cytokine receptor expression
2. Limited radius of effectiveness
3. Short half-lives |
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Term
| Which cytokines promote cell-mediated immunity by activating TH1? |
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Definition
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Term
| Which cytokines promote humoral-mediated immunity by activating TH2? |
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Definition
| IL-4, IL-5, IL-6, and IL-10 |
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Term
| Which cytokines promote muscosal responses by activating Treg cells? |
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Definition
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Term
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Definition
1. Stimulates helper T cells
2. Similar to TNFα
3. Leads to inflammation chemotaxis and adhesion |
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Term
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Definition
1. TH1 activating
2. Enhances NK cells and CTL
3. Produced by TH1 |
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Term
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Definition
| Known to be a growth factor for hematopoetic cells. |
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Term
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Definition
1. Produced by TH2 and mast cells
2. Promotes B cells and TH2
3. Induces allergy Ig class switch |
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Term
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Definition
1. Produced by TH2
2. Aids B cells
3. Pro-inflmmatory, but VERY pleiotropic
4. Wound healing
5. Produced during physiologic stress
6. Relatively long halflife, easy to see and indicates endocrine effects |
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Term
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Definition
| -A chemokine involved in inflammation |
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Term
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Definition
1. Anti-inflammatory
2. Involved in tolerance
3. But also weirdly a TH2 cytokine, so it suppresses TH1 |
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Term
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Definition
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Term
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Definition
1. Pro-inflammatory cytokine group
2. Involved in mycobacterial surveillance, autoimmunity, and allergy
3. Produced by Th17 |
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Term
| Describe the interferons, IFNα and IFNβ |
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Definition
| Produced by all cells and highly pleiotropic but many actions contribute to antiviral effects; e.g., well-known for induction of MHC class I molecules on all somatic cells, and inhibit viral replication. |
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Term
| Describe Interferon gamma (IFNγ) |
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Definition
1. Produced by TH1 cells, CTL, and NK cells and highly pleiotropic
2. Enhances Mac and NK function
3. Does everything you’d expect a Th1 cytokine to do |
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Term
| Describe Tumor Necrosis Factor Alpha (TNFα) |
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Definition
1. THE inflammatory cytokine
2. Produced and recognized by most cells in response to inflammation
3. Highly pleiotropic but involved in acute phase response
4. Similar to IL-1 |
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Term
| What is the role of Colony Stimulating Factors (CSFs?) |
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Definition
| To promote the formation and function of myeloid leukocytes in bone marrow |
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Term
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Definition
1. Granulocyte Colony Stimulating Factor (G-CSF)
2. Granulocyte-Macrophage Colony Stimularing Factor (GM-CSF)
3. Macrophage Colony Stimularing Factor (M-CSF) |
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Term
| Chemokines are a subset of cytokines. What is their role? |
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Definition
| They bind to the vascular bed and act as chemo-attractants during acute inflammation |
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Term
| Describe CXC or Alpha Chemokines |
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Definition
Secondary structural motif determines activity (receptor binding)
ELR+ attracts PMN
ELR— attracts T Cells |
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Term
| Describe CC or Beta Chemokines |
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Definition
| Either PMN or T Cell attractants, depending on receptor |
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Term
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Definition
Very big molecule
Chemotractant for PMN, Macs, NK, and T Cells to varying degrees |
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Term
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Definition
1. Anti-inflammatory
2. Down-regulates MHC II
3. Induces differentiation and inhibits proliferation in many cell types
4. Often involved in fibrosis and collagen production |
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Term
| Very briefly describe the signal pathway for cytokine receptors |
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Definition
1. Receptors composed of more than one subunit
2. Signaling usually involves kinases activating transcription factors |
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Term
| List the five major cytokine receptor families |
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Definition
1.Immunoglobulin Superfamily Receptors
2. Hematopoietin Receptor Family [includes most cytokine receptors involved in immune function]
3. Interferon Receptor Family
4. TNF Receptor Family
5. Chemokine Receptor Family |
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Term
| Describe the IL-2 receptor |
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Definition
-Three subunits with different affinities
-Different cells express different subunits
-Alpha subunit, for moderate affinity, is inducible on T cells which can give information about the T cell |
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