AB680 (Quemliclustat) is a highly potent, selective, reversible inhibitor of CD73 with Ki/IC50 of 4.9/70 pM (hCD73).
AB680 displays > 10,000-fold selectivity against related ecto-nucleotidases (CD39, NTPDases 2/3/8) and a large panel of unrelated enzymes, receptors, and ion channels.
AB680 completely inhibits CD73 enzymatic activity on CD8+ T cell, robustly restores proliferation of human CD4+ T-cells and reverses AMPmediated inhibition of IFN-γ and IL-2 production, limits the inhibitory effect of AMP on CD4+ T cell proliferation with IC50 of 4.5 nM.
AB680 also potently restored CD25 expression on human CD8+ T cells.
