Structure of the Superantigen Staphylococcal Enterotoxin B in Complex with TCR and Peptide-MHC Demonstrates Absence of TCR-Peptide Contacts.

Summary, in English

Superantigens are immune-stimulatory toxins produced by Staphylococcus aureus, which are able to interact with host immune receptors to induce a massive release of cytokines, causing toxic shock syndrome and possibly death. In this article, we present the x-ray structure of staphylococcal enterotoxin B (SEB) in complex with its receptors, the TCR and MHC class II, forming a ternary complex. The structure, in combination with functional analyses, clearly shows how SEB adopts a wedge-like position when binding to the β-chain of TCR, allowing for an interaction between the α-chain of TCR and MHC. Furthermore, the binding mode also circumvents contact between TCR and the peptide presented by MHC, which enables SEB to initiate a peptide-independent activation of T cells.

• Author: Karin Rödström; Karin Elbing; Karin Lindkvist
• Department/s: Medical Structural Biology
• Publishing year: 2014
• Language: English
• Pages: 1998-2004
• Publication/Series: Journal of Immunology
• Volume: 193
• Issue: 4
• Links: http://www.ncbi.nlm.nih.gov/pubmed/25015819?dopt=Abstract; http://dx.doi.org/10.4049/jimmunol.1401268
• Document type: Journal article
• Publisher: American Association of Immunologists
• Topic: Immunology in the medical area
• Status: Published
• Research group: Medical Structural Biology
• ISBN/ISSN/Other: ISSN: 1550-6606