[1] Charit Univ Med Berlin, Dept Dermatol, D-10117 Berlin, Germany
[2] Charit Univ Med Berlin, Allergy Ctr Charite, D-10117 Berlin, Germany
[3] Kings Coll London, Div Asthma Allergy & Lung Biol, MRC, London WC2R 2LS, England
[4] Kings Coll London, Asthma UK Ctr Allerg Mech Asthma, London WC2R 2LS, England
[5] Univ London Imperial Coll Sci Technol & Med, Leukocyte Biol Sect, MRC, London, England
[6] Univ London Imperial Coll Sci Technol & Med, Asthma UK Ctr Allerg Mech Asthma, London, England