These studies not only highlight the potential modulatory role played by NKT cells in atherosclerosis and lipid metabolism, but also raise the possibility that divergent roles may be played by iNKT and CD1d restricted cells such as type II NKT cells or other CD1d expressing cells.
They are unique in their restriction to lipid antigens presented in CD1d molecules, which underlies their role in lipid-driven disorders such as obesity and atherosclerosis.
In this Review, we provide an overview of NKT cells in the immune system, discuss CD1 molecules and lipid antigen presentation, and describe the interaction of the CD1d-NKT cell network with gut microbiota and its effect in modulating the activity or levels of NKT cells, which might in turn influence atherosclerosis.
Additionally, proteins transferring lipids during atherosclerosis, which are also important in the loading of lipids onto CD1d and possible endogenous ligands responsible for the activation of NKT cells during atherosclerosis will be discussed.