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Parekh VV, Singh AK, Wilson MT, Olivares-Villagómez D, Bezbradica JS, Inazawa H, Ehara H, Sakai T, Serizawa I, Wu L, Wang CR, Joyce S, Van Kaer L. Quantitative and qualitative differences in the in vivo response of NKT cells to distinct alpha- and beta-anomeric glycolipids. Journal of immunology (Baltimore, Md. : 1950). 2004 Sep 15;173(173). 3693-706.
Abstract
NKT cells represent a unique subset of immunoregulatory T cells that recognize glycolipid Ags presented by the MHC class I-like molecule CD1d. Because of their immunoregulatory properties, NKT cells are attractive targets for the development of immunotherapies. The prototypical NKT cell ligand alpha-galactosylceramide (alpha-GalCer), originally isolated from a marine sponge, has potent immunomodulatory activities in mice, demonstrating therapeutic efficacy against metastatic tumors, infections, and autoimmune diseases, but also has a number of adverse side effects. In vivo administration of alpha-GalCer to mice results in the rapid activation of NKT cells, which is characterized by cytokine secretion, surface receptor down-regulation, expansion, and secondary activation of a variety of innate and adaptive immune system cells. In this study, we have evaluated the in vivo immune response of mice to a set of structural analogues of alpha-GalCer. Our results show that, contrary to current thinking, beta-anomeric GalCer can induce CD1d-dependent biological activities in mice, albeit at lower potency than alpha-anomeric GalCer. In addition, we show that the response of NKT cells to distinct GalCer differs not only quantitatively, but also qualitatively. These findings indicate that NKT cells can fine-tune their immune responses to distinct glycolipid Ags in vivo, a property that may be exploited for the development of effective and safe NKT cell-based immunotherapies.