The B7-CD28 families of costimulators and inhibitory receptors Expression DCs DCs macrophages. i macropl macron macrophages. B cells B cells, othe lymphoid and. lymphoid and Name B7-1 B7-2 ICOS-L PD-L1 B7-H3 B7-H4 CD80) cD86) gands on APCs and other cells Receptors on T cells ITIM motit用uuwn 0 ITSM motif I Tyr.X.X-Met Name CD28 CTLA-4 IcOS PD-1 Expression T cells T cells T cells T cells, B cells constitutive inducible inducible Myleoid cells inducible Maior Costimulation Costimulation Negative regulation Negative function of naive T cells: of effector of T cells ulation ces pulsatory. of T cells T cellsThe B7-CD28 families of costimulators and inhibitory receptors