Agonist and antagonist activities of peptide sequences of interest. Upper panel: Agonist activity of peptides in U937 cells is displayed as Log EC50 (± SEM), EC50 in nM and as a calculated maximum (M) relative to the response of the cells to 10 μM of the C3aR agonist, FLPLAR. Lower panel: Antagonists activity of peptides in U937 cells is displayed as Log IC50 (± SEM), IC50 in nM and as a calculated minimum (M) relative to the response of the cells to 10 μM of the C3aR agonist, FLPLAR, following treatment with the peptides of interest. n = 3–6