CD1d-restricted natural killer T cells (NKT cells) possess a wide range of effector and regulatory activities that are related to their ability to secrete both T helper 1 (Th1) cell- and Th2 cell-type cytokines. We analyzed presentation of NKT cell activating α galactosylceramide (αGalCer) analogs that give predominantly Th2 cell-type cytokine responses to determine how ligand structure controls the outcome of NKT cell activation. Using a monoclonal antibody specific for αGalCer-CD1d complexes to visualize and quantitate glycolipid presentation, we found that Th2 cell-type cytokine-biasing ligands were characterized by rapid and direct loading of cell-surface CD1d proteins. Complexes formed by association of these Th2 cell-type cytokine-biasing αGalCer analogs with CD1d showed a distinctive exclusion from ganglioside-enriched, detergent-resistant plasma membrane microdomains of antigen-presenting cells. These findings help to explain how subtle alterations in glycolipid ligand structure can control the balance of proinflammatory and anti-inflammatory activities of NKT cells.
Bibliographical noteFunding Information:
This work was supported by NIH grants AI45889 (S.A.P.) and AI057519 (A.R.H.). G.S.B. is a former Lister Institute-Jenner Research Fellow and received support from the Medical Research Council (U.K.), the Wellcome Trust (084923/B/08/7), a Royal Society Wolfson Research Merit Award, and the James Bardrick Research Chair. K.O.A.Y. was supported by the Medical Scientist Training Program of the Albert Einstein College of Medicine, E.S.J. received a Howard Hughes Medical Institute Training Fellowship, and M.G. was supported by NIH Training Grant 5T32CA009173. The authors acknowledge technical support from the Einstein Analytical Imaging and Flow Cytometry Core Laboratories supported by the NCI funded Einstein Cancer Center (CA13330) and the Einstein Center for AIDS Research (AI51519). S.A.P. is a paid consultant for Vaccinex, Inc. (Rochester, NY).