[1] Univ Manitoba, Dept Physiol, Manitoba Inst Child Hlth, Winnipeg, MB, Canada
[2] Univ Melbourne, Dept Pharmacol, Melbourne, Vic 3010, Australia
[3] Univ Manitoba, Dept Immunol, Winnipeg, MB, Canada
[4] Univ Penn, Med Ctr, Pulm Allergy & Crit Care Div, Philadelphia, PA 19104 USA
[5] McGill Univ, Meakins Christie Labs, Dept Med, Montreal, PQ, Canada
[6] McGill Univ, Dept Med, Div Resp, Montreal, PQ, Canada
[7] Univ Sydney, Dept Pharmacol, Sydney, NSW 2006, Australia