CD1D and neoplasm: Some of the mechanisms by which lipid changes can modulate NKT cell dependent immune functions, directly or indirectly, that will be discussed here are (1) alteration in the quality of lipid antigen repertoire that can be presented to NKT cells, (2) impaired antigen cross presentation by DCs either by affecting the antigen processing machinery or MHC and CD1d surface expression, (3) modified quality and quantity of lipid reactive NKT cells, and (4) homing of NKT cells to the tumor sites.