Regulatory cytokines

Cytokines Regulatory proteins, such as interleukins and lympho-kines, that are released by cells of the immune system and act as intercellular mediators in the generation of an immune response. 

Kim, K. J., Abrams, J., Alphonso, M., Pearce, M., Thorbecke, G. J., and Palladino, M. Role of endogenously produced interleukin-6 as a second signal in murine thymocyte proliferation induced by multiple cytokines Regulatory effects of transforming growth factor-beta. Cell. Immunol. 131, 261-271 (1990). 

Cytokines—regulatory proteins released by cells—lake part in cell growth and cell differentiation, and they have strong involvement with the HPA axis. In humans, psychosocial stress causes increases in serum levels of cytokines, and when such increases occur in a mother during pregnancy, the result can... 

As the immune system evolved as a means to protect the body from infection and eliminate cells (e.g., virus containing, senescent, or tumor cells), various mechanisms (e.g., anti-inflanunatory cytokines, regulatory T cells) also evolved to limit or mitigate the damage to normal tissues caused by an immune response or prevent attack on normal cells. Uncontrolled immunostimulation may result in circulatory collapse or damage to tissues, which may be life threatening. 

The copied host-defense genes are primarily found in two classes of large DNA viruses, the poxviruses and the herpesviruses, where examples of copied cytokines, cytokine receptors, chemokines and chemokine receptors, complement-control proteins, and other cytokine-regulatory proteins (3,6,9,10) are known the sequence relationship of the viral and host homolog in these examples tends to be rather weak (25 5% amino... 

Family of enzymes phosphorylating phosphatidylinositol (Ptdlns), PtdIns(4)phosphate, and PtdIns(4,5)phosphate in the 3-position. The Ptdlns(3 phospholipids are second messengers in processes like cell growth, cytoskeletal rearrangement, and vesicular transport. PI 3-kinases are heterodimers composed of a catalytic and a regulatory subunit. The enzymes are activated by insulin, many growth factors, and by a variety of cytokines. Their activity can be inhibited by wortmannin and LY294002. 

The secretion of extracellular matrix proteins is also a function of smooth muscle cells but, since it occurs concurrently with other activities, it does not seem to constitute a physiological state. However, the fraction of the cellular resources which are devoted to it must be regulated these regulatory mechanisms are virtually unknown. In addition, it should be anticipated that autocrine activity occurs as well, involving peptides, prostaglandins, cytokines, and nitric oxide. 

It is accepted that oxidation of LDL is a key event in endothelial injury and dysfunction. Oxidised LDL (oxLDL) may directly injure the endothelium and trigger the expression of migration and adhesion molecules. Monocytes and lymphocytes interact with oxLDL and the phagocytosis which follows leads to the formation of foam cells, which in turn are associated with the alteration of the expression pattern of growth regulatory molecules, cytokines and pro-inflammatory signals. The proposed role of oxLDL in atherogenesis, based on studies in vitro, is shown in Fig. 2.1. 

Cohen-Hillel E, Yron I, Meshel T, Soria G, Attal H, Ben-Baruch A. CXCL8-induced FAK phosphorylation via CXCR1 and CXCR2 Cytoskeleton- and integrin-related mechanisms converge with FAK regulatory pathways in a receptor-specific manner. Cytokine 2006 33 1-16. 

Upon activation, mast cells release numerous mediators, including vasoactive amines, proteases, pro-inflammatory cytokines (e.g. IL-ip, IL-6, IL-18 and TNF-a) and also regulatory Th2 cytokines (e.g. IL-4, IL-10 and IL-13) (Burd et al., 1989 Gordon and Galli, 1990 Marietta el al., 1996 Toru et al., 1998 Aoki et al., 1999 Lorentz et al, 2000). Therefore, the mastocytosis in the infected mucosa represents an immunopathological rather than a protective response. Indeed, our studies have shown that expulsion of T. spiralis from TNF-Rl / or iNOS / mice was achieved in the absence of a substantial mastocytosis and subsequent amelioration of enteropathy (Lawrence etal., 1998, 2000). 

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