Casset Anne, Purohit Ashok, Birba Emile, Chenard Marie-Pierre, Uring Lambert Béatrice, Bahram Siamak, Meyer Pierre, Pauli Gabrielle, De Blay Frédéric
Département de Pneumologie, Hôpital Lyautey, Hôpitaux Universitaires de Strasbourg, BP 426, 67091 Strasbourg, France.
J Aerosol Med. 2007 Winter;20(4):509-18. doi: 10.1089/jam.2007.0591.
Although major house dust mite allergen (Der p 1) is carried mainly on large particles (>10 microm), standard bronchial challenge tests (BCT) use nebulizers that deliver smaller particles (sizes from 1 to 5 microm) and may therefore not reflect actual domestic exposure. The objective of this study was to evaluate the influence of particle size of Dermatophagoides pteronyssinus extract on bronchial response. Specific BCT were performed with different mass median aerodynamic diameters (MMAD): 1.1, 5.6, and 9.7 microm. Each of the 19 mite-sensitized patients underwent mite BCT three times, once with each nebulizer. IL-5 levels were assessed in induced sputum and blood samples. The PD(20) for Der p 1 differed substantially with particle size, with less Der p 1 (11.2 ng) needed to produce a PD(20) with the largest particles (9.7 microm), compared to 18.1 ng for the 5.6 microm particles and 142.5 ng for the 1.1 microm particles (p < 0.0001). Large particles also induced an early phase response significantly more often than small particles (100% vs. 63%). Although the late phase reaction (LPR) frequency was similar with all three particle sizes, lower mean oral corticosteroid doses were needed to treat LPR with the largest particles (23 mg), compared to the smaller particles, with 34 mg for the 5.6 microm particles and 51 mg for the 1.1 microm. The 1.1 microm particles produced a significantly greater increase in IL-5 concentrations in sputum and blood compared to the larger particles. Large particles clearly play a role in the immediate bronchial response in asthmatics sensitized to mites and, therefore, should be included in pharmacological studies in humans.
虽然主要的屋尘螨变应原（Der p 1）主要附着于大颗粒（>10微米）上，但标准支气管激发试验（BCT）使用的雾化器会产生较小颗粒（粒径为1至5微米），因此可能无法反映实际的家庭暴露情况。本研究的目的是评估粉尘螨提取物的粒径对支气管反应的影响。采用不同的质量中值空气动力学直径（MMAD）进行特异性BCT：1.1、5.6和9.7微米。19名螨致敏患者每人接受三次螨BCT，每次使用一种雾化器。对诱导痰和血样中的白细胞介素-5水平进行评估。Der p 1的PD(20)随粒径有显著差异，产生PD(20)所需的Der p 1量较少（11.2纳克），最大颗粒（9.7微米）与5.6微米颗粒的18.1纳克和1.1微米颗粒的142.5纳克相比（p < 0.0001）。大颗粒比小颗粒更常引发早期反应（100%对63%）。虽然三种粒径的晚期反应（LPR）频率相似，但与较小颗粒相比，用最大颗粒（23毫克）治疗LPR所需的口服皮质类固醇平均剂量更低，5.6微米颗粒为34毫克，1.1微米颗粒为51毫克。与较大颗粒相比，1.1微米颗粒使痰和血中的白细胞介素-5浓度显著升高。大颗粒显然在对螨致敏的哮喘患者的即时支气管反应中起作用，因此应纳入人体药理学研究。
