Fig. 3.
ANXA1 peptides directly interact with recombinant as well as endogenous PMN ALXR. a, CHO-Gqo-ALXR cells were added to the upper compartment of a microchamber (5 × 104 cells per well). Chemotaxis was initiated by addition of Ac2-26 peptide (100 μM; 
) or aspirin-triggered lipoxin A4 analog 1 (ATLa1; 100 nM; ■) to the lower compartment. □, vehicle. b, CHO-Gqo-ALXR cells were pretreated with Ac2-26 peptide for 30 min at 37 °C and added to the upper compartment of a microchamber (5 × 104 cells per well). Chemotaxis was initiated by addition of ATLa1 (100 nM) to the lower compartment. c, Human PMNs were added to the upper compartment of a microchamber (5 × 104 cells per well). Chemotaxis was initiated by addition of Ac2-26 peptide (1–10 μM; ■) to the lower compartment. In some cases, cells were treated with 10 (
) or 100 nM (□) ATLa1 for 30 min at 37 °C. #, P = 0.01, versus vehicle; *, P < 0.01, versus Ac2-26 alone (a and c) or % inhibition of ATLa1- evoked chemotaxis (*, P = 0.02; **, P < 0.01, versus ATLa1 alone in b). Data represent the mean ± s.e.m. from n = 3 experiments. d, Fura2-AM-loaded human PMNs (5 × 106 cells/incubation) were incubated with the different stimuli, and rapid changes in intracellular [Ca2+] measured by fluorimetry. Additions of agonists are denoted by arrows. hrANXA1: human recombinant annexin 1. Traces are representative of 3 independent experiments.