. 2023 Nov 29;4(4):102758. doi: 10.1016/j.xpro.2023.102758

Table 2.

Validation of ligand activity in HMDMs

	Receptor of interest	Validation method
Agonist	C5aR1	Pre-treat cells with PMX53 (10 μM), does it block ligand X induced ERK signaling?
	C3aR	Pre-treat cells with SB290157 (10 μM), does it block ligand X induced ERK signaling?
Antagonist	C5aR1	Pre-treat cells with ligand X, does it block hC5a (1 nM) induced ERK signaling?
	C3aR	Pre-treat cells with ligand X, does it block hC3a (5 nM) induced ERK signaling?

Note: Alternative specific C5aR1 inhibitors (e.g., Avacopan, PMX205, JPE-1375, etc.) can also be used. A list of potent and commonly used C5aR1 inhibitors can be found in our previous publication¹ and the IUPHAR/BPS Complement Peptide Receptor Guide to Pharmacology database.³ SB290157 is the only commercially-available C3aR inhibitor and has acknowledged off-target activity,²^,¹⁸ however, in HMDMs at this concentration, it acts as a full-antagonist for C3aR.²^,¹⁹