Lipid Rafts & Co.: an integrated model of membrane organization in T cell activation.

Department of Internal Medicine III, Division of Endocrinology and Metabolism, Medical University of Vienna, Vienna, Austria.
Progress in Lipid Research (Impact Factor: 12.96). 06/2006; 45(3):187-202. DOI: 10.1016/j.plipres.2006.01.002
Source: PubMed

ABSTRACT The model of membrane compartmentalization by self-organizing functional lipid microdomains, named lipid rafts, has been a fruitful concept resulting in great progress in understanding T cell signal transduction. However, due to recent results it has become clear that lipid rafts describe only one out of several membrane organizing principles crucial for T cell activation besides fences and pickets and protein-protein interactions that take part in the formation of the immunological synapse as a highly organized structure at the T cell contact site to the antigen-presenting cell. This review describes the concepts of lipid rafts and other membrane organizing principles to evolve a novel integrated model on the functional role of microdomains in immunological synapse formation and T cell activation. Further research has to elucidate the relative contribution and interrelation of different modes of membrane organization in productive T cell activation.

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