[1] Chinese Univ Hong Kong, Fac Med, Sch Biomed Sci, Shatin, Hong Kong, Peoples R China
[2] Hong Kong Sanat & Hosp, Allergy Ctr, Happy Valley, Hong Kong, Peoples R China
[3] Stanford Univ, Sch Med, Dept Pathol, Stanford, CA 94305 USA
[4] Univ Hong Kong, Dept Paediat & Adolescent Med, Pok Fu Lam, Hong Kong, Peoples R China