Not known Facts About How Superantigens Bind MHC - The Journal of Immunology

The biological strength of the SAg (its capability to promote) is figured out by its affinity for the TCR. SAgs with the highest affinity for the TCR elicit the strongest reaction. SPMEZ-2 is the most powerful SAg found to date. T-cell signaling [edit] The SAg cross-links the MHC and the TCR causing a signaling path that results in the expansion of the cell and production of cytokines.

Superantigens

Low levels of Zap-70 have been found in T-cells triggered by Droops, suggesting that the typical signaling pathway of T-cell activation suffers. It is hypothesized that Fyn instead of Lck is triggered by a tyrosine kinase, resulting in the adaptive induction of anergy. Both the protein kinase C path and the protein tyrosine kinase paths are triggered, resulting in upregulating production of proinflammatory cytokines.

Frontiers - Superantigen Recognition and Interactions: Functions, Mechanisms and Applications - Immunology

Direct impacts [edit] Droop stimulation of antigen presenting cells and T-cells generates a response that is mainly inflammatory, concentrated on the action of Th1 T-helper cells. Some of the significant products are IL-1, IL-2, IL-6, TNF-, gamma interferon (IFN-), macrophage inflammatory protein 1 (MIP-1), MIP-1, and monocyte chemoattractant protein 1 (MCP-1).

Deletion or anergy of triggered T-cells follows infection. neobladder surgery results from production of IL-4 and IL-10 from extended direct exposure to the toxic substance. The IL-4 and IL-10 downregulate production of IFN-gamma, MHC Class II, and costimulatory molecules on the surface of APCs. These effects produce memory cells that are unresponsive to antigen stimulation.

Little Known Questions About From Superantigens to “Real” Viral Antigens - Mary Ann.

MHC crosslinking likewise triggers a signaling path that suppresses hematopoiesis and upregulates Fas-mediated apoptosis. IFN- is another item of prolonged Droop direct exposure. This cytokine is closely related to induction of autoimmunity, and the autoimmune illness Kawasaki disease is known to be caused by SAg infection. Droop activation in T-cells causes production of CD40 ligand which triggers isotype switching in B cells to Ig, G and Ig, M and Ig, E.

The toxic results of the microbe and SAg likewise damage tissue and organ systems, a condition understood as poisonous shock syndrome. If the preliminary inflammation is endured, the host cells become anergic or are erased, leading to a badly jeopardized immune system. Superantigenicity independent (indirect) results [edit] Apart from their mitogenic activity, Droops have the ability to cause signs that are characteristic of infection.