@article {542451,
	title = {Programmed death-1 ligand 1 interacts specifically with the B7-1 costimulatory molecule to inhibit T cell responses.},
	journal = {Immunity},
	volume = {27},
	number = {1},
	year = {2007},
	month = {2007 Jul},
	pages = {111-22},
	abstract = {Pathways in the B7:CD28 family of costimulatory molecules regulate T cell activation and tolerance. B7-dependent responses in Cd28(-/-)Ctla4(-/-) T cells together with reports of stimulatory and inhibitory functions for Programmed Death-1 Ligand 1 or 2 molecules (PD-L1 or PD-L2) have suggested additional receptors for these B7 family members. We show that B7-1 and PD-L1 interacted with affinity intermediate to that of B7-1:CD28 and B7-1:CTLA-4. The PD-L1:B7-1 interface overlapped with the B7-1:CTLA-4 and PD-L1:PD-1 (Programmed Death-1) interfaces. T cell activation and cytokine production were inhibited by the interaction of B7-1 with PD-L1. The responses of PD-1-deficient versus PD-1,B7-1 double-deficient T cells to PD-L1 and of CD28,CTLA-4 double-deficient versus CD28,CTLA-4,PD-L1 triple-deficient T cells to B7-1 demonstrated that PD-L1 and B7-1 interact specifically to inhibit T cell activation. Our findings point to a substantial bidirectional inhibitory interaction between B7-1 and PD-L1 and add an additional dimension to immunoregulatory functions of the B7:CD28 family.},
	keywords = {Animals, Antigens, CD274, Antigens, CD80, Cell Line, Cell Proliferation, Cells, Cultured, Cercopithecus aethiops, COS Cells, Cytokines, Down-Regulation, Humans, Ligands, Membrane Glycoproteins, Mice, Mice, Inbred C57BL, Mice, Knockout, Peptides, Protein Binding, T-Lymphocytes},
	issn = {1074-7613},
	doi = {10.1016/j.immuni.2007.05.016},
	author = {Butte, Manish J and Keir, Mary E and Phamduy, Theresa B and Sharpe, Arlene H and Freeman, Gordon J}
}
