Lipid and Carbohydrate Modifications of alpha-Galactosylceramide Differently Influence Mouse and Human Type I Natural Killer T Cell Activation.
Birkholz, A., Nemcovic, M., Yu, E.D., Girardi, E., Wang, J., Khurana, A., Pauwels, N., Farber, E., Chitale, S., Franck, R.W., Tsuji, M., Howell, A., Van Calenbergh, S., Kronenberg, M., Zajonc, D.M.(2015) J Biol Chem 290: 17206-17217
- PubMed: 26018083 
- DOI: https://doi.org/10.1074/jbc.M115.654814
- Primary Citation of Related Structures:  
4Y16 - PubMed Abstract: 
The ability of different glycosphingolipids (GSLs) to activate type I natural killer T cells (NKT cells) has been known for 2 decades. The possible therapeutic use of these GSLs has been studied in many ways; however, studies are needed in which the efficacy of promising GSLs is compared under identical conditions. Here, we compare five unique GSLs structurally derived from α-galactosylceramide. We employed biophysical and biological assays, as well as x-ray crystallography to study the impact of the chemical modifications of the antigen on type I NKT cell activation. Although all glycolipids are bound by the T cell receptor of type I NKT cells in real time binding assays with high affinity, only a few activate type I NKT cells in in vivo or in vitro experiments. The differences in biological responses are likely a result of different pharmacokinetic properties of each lipid, which carry modifications at different parts of the molecule. Our results indicate a need to perform a variety of assays to ascertain the therapeutic potential of type I NKT cell GSL activators.
Organizational Affiliation: 
From the Division of Cell Biology and Division of Developmental Immunology,La Jolla Institute for Allergy and Immunology, La Jolla, California 92037, the Division of Biological Sciences, University of California at San Diego, La Jolla, California 92037.