CD1D and graft versus host disease: For example, distinct from traditional T cells perceiving peptide antigens dependent on MHC molecules, iNKT cells recognize lipid-based antigens presented by the β2M-associated MHC I-like molecule CD1d, which signifies that the function of NKT cells is restricted by CD-1d rather than classical TCR-MHC interaction, thus reducing risk for GVHD 185, 186.