Figure 2. Regulation of human PMN activation by lipoxin A₄ involves calcineurin dependent and independent pathways.

Freshly isolated human PMN from healthy donors were exposed (5 min, 37°C) to LXA₄ (100nM), cyclosporin A (200 nM) or vehicle (0.1% ethanol) prior to TNFα (10 ng/ml) and (a) calcineurin activity and (b–d) cytokine release were determined (see Methods). Values reported are the mean ± S.E. for n ≥ 3 separate PMN donors. *P < 0.01 (as compared to vehicle), **P < 0.05 (as compared to TNFα) and ***P < 0.05 (for CSA compared to LXA₄).