Cytokines, Chemokines, and Growth Factors

Cytokines are regulatory proteins secreted primarily by white blood cells but also by a variety of other cells in the body their functions include numerous effects on cells of the immune system and inflammatory processes (Vilcek, 2003). Most cytokines are single polypeptide chains, although they may form multimers in biological fluids. As an exceptionally large and diverse group of factors, cytokines 

Cytokines can be grouped into families based upon their structural homology or structural homology of their receptors. Below, is an effort to group cytokines and their families based on the strnctnral homology of their receptors. This classification helps provide a foundation for thinking about these factors and their role in the brain. 

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Many inflammatory mediators have now been implicated in COPD, which include lipids, free radicals, cytokines, chemokines, and growth factors (7). These mediators are derived from inflammatory and structural cells in the lung and interact with each other in a complex manner. 

CNS-immune system interactions are regulated by cytokines, chemokines, and growth factors. Immune cells, after... 

In summary, cytokines and growth factors discussed in this section are implicated in the pathophysiological processes of AD of which activated microglia and macrophage perpetuate the inflammatory response that ultimately causes neuronal injury. However, it should be noted that inflarrrmation orchestrated by cytokines, chemokines, and growth factors may only play minor roles, as some researchers regard AD as a neurodegenerative disease rather than neuroinflammatory disease. 

Meeuwsen S, Persoon-Deen C, Bsibsi M, Ravid JM, Noort JM (2003) Cytokine, chemokine and growth factor gene profiling of cultured hmnan astrocytes after exposure to proinflammatory stimuh. Glia 43 243-253. 

Leukocytes are a major source of profibrotic mediators [i.e., TGF-(3 and platelet-derived growth factor (FDGF)], which cause wound scarring (61,92). Recmited leukocytes communicate with other cells via release of cytokines, chemokines, and growth factors that are central to driving fibrosis during woimd repair (63,67). 

Figure 2 Injury to the epithelium and adjacent endothelium leads to a lung remodeling, which causes fihrosis. (A) Noninflammatory mechanism—injury to the epithelium and endothelium causes only these cells to upregulate TGF-P, PDGF, and other mediators (cytokines, chemokines, and growth factors), which result in fibroplasia. (B) While injured epithelium and endothelium release some profihrotic mediators, it is the persistent inflammatory cells that are most important in driving (via cytokine release) fibrosis.

Based on numerous studies of the periprosthetic tissues, it is the activation of both recruited and resident cells that leads to the production and release of cytokines, chemokines, and growth factors by these cells. The acute response proinflammatory cytokines and chemokines produced by activated fibroblasts, macrophages, and mast cells include IL-la, 1L-1(3, lL-6, and TNF-a [24—27]. In most inflammatory reactions, the acute phase is typically a short-lived response, followed by the proinflammatory cytokine and chemokine release that perpetuates a chronic inflammatory response, such as lL-6, lL-8, and monocyte chemoattractant protein (MCP-1), which are also detected... 

Taub, D. D. (1996) Chemokines-Leukocyte Interactions The Voodoo That They Do So Well. Cytokine and Growth Factor Reviews 7(4), 355-376. 

All of the above families are imperative for homeostatic functions as well as the orchestration of response to pathogenic insult by the immune system. As investigations carry on, this large family will likely see the emergence of additional cytokines and growth factors, and the family and sub-families of cytokine, growth factor, or chemokine receptors will continue to evolve and expand. 

Johnson, Z., Proudfoot, A. E., Handel, T. M. (2005). Interaction of chemokines and glycosaminoglycans A new twkt in the regulation of chemokine function with opportunities for therapeutic intervention. Cytokine and Growth Factor Reviews, 16(6), 625-636. 

The absence of serum is vital,because it contains cytokines and growth factors that will mask the effect of the chemokine added, preventing the formation of a steep chemokine gradient. 

Several immunoassays can now be performed with imaging-based ECL instruments manufactured by Meso Scale Discovery (Chap. 3, Fig. 3.7) [22, 23]. Approximately 150 immunoassays are currently available from this company. These include phosphoprotein and intracellular markers, cardiac markers, vascular markers and growth factors, fertility markers, Alzheimer s disease markers, hypoxia markers, toxicology, metabolic markers, bone markers, bioprocess assays, and cytokine and chemokine immunoassays. Further description and discussion on the particular immunoassays of interest may be found in Ref. [22]. 

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