Immune response signal transduction

Gough DJ, Sabapathy K, Ko EY, Arthur HA, Schreiber RD, Trapani JA, Clarke CJ, Johnstone RW (2007) A novel c-Jun-dependent signal transduction pathway necessary for the transcriptional activation of interferon gamma response genes. J Biol Chem 282 938-946 Guidotti LG, Chisari EV (2001) Noncytolytic control of viral infections by the innate and adaptive immune response. Annu Rev Immunol 19 65-91... 

Phagocytosis and encapsulation, in which pathogens are sequestered within several layers of cells, are the predominant cellular immune responses. Genetic and molecular studies have shown that bacterial products are recognized24 and transduced by host cells25 26 by similar pattern recognition receptors and signal transduction pathways in both vertebrates and invertebrates. 

Geng, Y. et al., Effects of nicotine on the immune response. I. Chronic exposure to nicotine impairs antigen receptor-mediated signal transduction in lymphocytes, Toxicol. Appl. Pharmacol., 135, 268-287, 1995. 

About 10-20% of all transmembrane proteins that are targeted to the ER and subsequently enter the secretory pathway are subject to post-translational modification with glycosylphosphatidyl-inositol (GPI). Proteins bearing the GPI anchor are involved in signal transduction, immune response, cancer cell invasion, and metastasis and the pathobiology of trypanosomal parasites. The structure of the GPI anchor has been analyzed for mammals, protozoa, and yeast. The general structure of the glycolipid structure is shown in Scheme 4. 

The TCR is composed of integral membrane protein that recognizes the antigen and as a consequence its activation produces an immune response to eliminate the antigen. This process results in the development of CD4+ or CD8+ cells from the precursor T cells. It involves other cell surface receptors and downstream signal transduction mechanisms. 

The monoclonal antibodies used as immunosuppressive agents in tissue transplantation include muromonoab-CD3, daclizumab and basiliximab. Muromonoab-CD3 binds to a specific site on CD3 receptors and interferes with the ability of the TCR to bind the antigen and also inhibits CD3 receptor-dependent signal transduction mechanisms, all of which result in immune suppression. Both daclizumab and basiliximab are monoclonal antibodies directed against IL-2 receptors and consequently inhibit IL-2-dependent responses after tissue transplantation, resulting in immune suppression. The monoclonal antibodies used as immunosuppressive agents are described in detail in Chapter 5. 

This increase is thought to be one of the early steps involved in so-called signal transduction and can result in the activation of enzyme systems responsible for subsequent metabolic or developmental changes. Lymphocytes show increases in intracellular calcium in response to many kinds of specific and nonspecific surface ligand binding, some of which lead to the cellular changes that we associate with an immune response. Many other classes of cells also show calcium changes in response to stimulation. 

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