Potent and selective GPR84 biased agonist (EC50 = 33 nM). Exhibits no significant activity in a panel of 168 other GPCRs. Exhibits bias for G protein signaling pathways. Induces morphological changes in primary murine bone marrow-derived macrophages (BMDMs) in a cellular impedance assay, and promotes phagocytosis by M1 polarized U937 cells. Induces migration of primary human monocytes, but has no effect on macrophage chemotaxis.
D18 is an immune modulator that acts as a dual agonist for TLR7/8 (with EC50 values of 24 nM for hTLR7 and 10 nM for hTLR8, respectively). It enhances the expression of PD-L1 through epigenetic regulation, thereby increasing the sensitivity of tumors to PD-1/PD-L1 blockade. Additionally, D18 functions as a cytotoxin for ADC synthesis, specifically for the ADC HE-S2 [1].