Table 1.

Expression and function of the B7 family ligands and their receptors of the CD28 family

The B7 family ligandsThe CD28 family receptors
ExpressionNameNameExpressionFunction
Group I
APCB7-1Embedded ImageCD28T cellsCostimulation
APCB7-2CTLA-4Activated T cellsCoinhibition
APC, tissueB7hEmbedded ImageICOSActivated T cellsCostimulation
Group II
APC, tissue, tumorsPD-L1Embedded ImagePD-1Activated T, B, and myeloid cellsCoinhibition
APCPD-L2Embedded ImagePD-1Activated T, B, and myeloid cellsCoinhibition
Group III
APC, tissue, tumorsB7-H3Embedded ImageUnidentified receptorActivated T cellsCoinhibition
Tissue, tumorsB7xEmbedded ImageUnidentified receptorActivated T cellsCoinhibition