Glycolipid Stimulators for NKT Cells Bearing Invariant Vα19-Jα33 TCR α Chains

Attempts have been made to find specific antigens for a novel NKT cell subset bearing invariant Vα19-Jα33 TCR α chains (Vα19 NKT cell). Comprehensive examinations revealed substantial antigenic activity in synthetic α- mannosylceramide (ManCer) that was presented by MR1. Structural modification of the sphingosine moiety of α-ManCer improved antigenic activity to enhance either Th1 or Th2 -promoting cytokine production by Vα19 NKT cells. Such α- ManCer analogues will be useful for developing new therapies as immunomodulators.