Cytokines Flashcards (Ai)

Vocabulary flashcards for reviewing cytokines and their roles in the immune response based on lecture notes.

Cytokines

Proteins secreted by cells of the immune system that regulate immune responses (e.g., proliferation, differentiation, and maturation of nearby cells).

Lymphokines

Cytokines produced by T cells.

Monokines

Cytokines produced by monocytes.

Pleiotropy

The ability of one cytokine to act on different cell types.

Redundancy

Many different cytokines may have similar effects.

Synergy

Cytokines work optimally only when in association with other cytokines.

Antagonism

Cytokines prevent or inhibit the action of others.

Autocrine (Cytokine Activity)

They bind to receptors on the cell that produced them.

Paracrine (Cytokine Activity)

They bind to receptors on cells in close proximity to the cell of origin.

Endocrine (Cytokine Activity)

They spread throughout the body, affecting cells in distant locations from the source of production.

Interleukins

Cytokines that regulate the interactions between lymphocytes and other leukocytes.

Interferons

Antiviral cytokines that are produced in response to virus infection or immune stimulation and interfere with viral RNA and protein synthesis.

Tumor Necrotic Factors (TNFs)

Cytokines derived from macrophages and T cells that can kill tumor cells, with TNF-α being the key mediator of acute inflammation.

Growth Factors

Cytokines that control leukocyte production by regulating stem cell growth, ensuring the body is supplied with sufficient cells to defend itself.

Chemokines

Family of cytokines that play an important role in leukocyte circulation and migration, especially in inflammation, and act primarily as chemotactic factors and leukocyte activators.

Interleukin 1

Plays a critical role in inflammation and is key in fever, hematopoiesis, appetite control, bone metabolism, and acquired immunity. Major source is macrophage.

Interleukin-2

Produced by Th1 cells and targets T cells, B cells, and NK cells. Activates helper and cytotoxic T cells and NK cells.

Interleukin 3

Derived from activated Th1 and Th2 cells, NK cells, eosinophils and mast cells. Stimulates the growth and maturation of bone marrow stem cells for eosinophils, neutrophils and monocytes.

Interleukin 4

Produced by activated Th2 cells, mast cells and activated basophils. Stimulates the growth and differentiation of B cells and induces B cells to switch to IgE production.

Interleukin 5

Produced by Th2 cells, mast cells and eosinophils. Controls the eosinophil production by stimulating growth and differentiation of eosinophil precursors in the bone marrow.

Interleukin 6

Produced by activated macrophages but also by T and B cells as well as muscle cells during exercise. Promotes IL-2 production, T cell differentiation and is required for the final maturation of B cells into plasma cells.

Interleukin 7

Produced by bone marrow and thymic stromal cells. Regulates the activity of lymphoid stem cells and is necessary for lymphocytes to produce functioning antigen receptors.

Interleukin 9

A stem cell growth factor produced only by Th2 cells. Promotes the growth of helper T cells and mast cells and contribute to the development of allergic diseases.

Interleukin 10

An immunosuppressive and anti-inflammatory cytokine that regulates inflammation as well as T cell, NK cells and macrophage function. Mainly produced by Th2 cells.

Interleukin 11

Produced by bone marrow stromal cells, epithelial cells and fibroblasts. Stimulates B cell growth in association with IL-6.

Interleukin 12

Produced by monocytes, macrophages, dendritic cells, B cells and keratinocytes. Promotes Th1 activity by inducing secretion of IL-2 and IFN-γ and enhances T and NK cell proliferation and cytotoxicity.

Interleukin 13

Produced by Th2 cells, cytotoxic T cells, mast cells and dendritic cells. Has structural and biological characteristics similar to IL-4 and Required for optimal induction of IgE.

Interleukin 14

Produced by T cells and some malignant B cells. Inhibits immunoglobulin secretion and selectively expands some B cell subpopulations.

Interleukin 15

Derived from activated macrophages, dendritic cells, endothelial cells and fibroblasts. Essential for the prolonged survival of memory cells.

IL-16

Produced by CD8+ T cells, eosinophils, dendritic cells and mast cells. Regulates CD4+ T cell recruitment and activation and a potent chemoattractant for CD4+ T cells, eosinophils, dendritic cells and macrophages

IL-17

A family of cytokines involved in regulating immune responses. Induce the production of cytokines by cells and proliferation of T cells and myeloid stem cells, also a link between T cell activation and the mobilization of neutrophils via chemokines.

Interferon α

Produced in large quantities by lymphoid dendritic cells and smaller amount by lymphocytes, monocytes and macrophages in response to viral infection, it is also a potent stimulator of both innate and adaptive immunity.

Interferon β

Produced by fibroblasts in response to viral infection and interferes with viral RNA and protein synthesis.

Interferon-γ

Produced by Th1 cells and some T cells and NK cells. Stimulated B cell production and enhances T cell production of MHC class I molecules but not production of MHC class II molecules.

TNF-α

Produced by macrophages, mast cells, T cells and endothelial cells, B cells and fibroblasts. Mediates many immune and inflammatory functions and regulates the growth of many cell types.

TNF-β

Produced by Th1 cells and activated CD8+ T cells. Kills tumor cells and activates neutrophils, macrophages, endothelial cells and B cells.

Granulocyte Colony-stimulating factor (G-CSF)

Produced by macrophages, endothelial cells and fibroblasts and regulates the maturation of granulocyte progenitors into mature neutrophils.

Macrophage Colony-stimulating factors (M-CSF)

Act on monocyte progenitors to induce their proliferation and differentiation and promote macrophage cytotoxicity.

Transforming Growth Factors β (TGF- β)

Regulate cell division, enhance the deposition of extracellular matrix proteins and most importantly, they are immunosuppressive.