Chang J H, Chan H, Quirce S, Green T, Noertjojo K, Lam S, Frew A, Keown P, Chan-Yeung M
Department of Medicine, University of British Columbia, Vancouver, Canada.
J Allergy Clin Immunol. 1996 Nov;98(5 Pt 1):922-31. doi: 10.1016/s0091-6749(96)80008-x.
There is considerable evidence that T cells may play an important role in asthma. The purpose of this study was to determine whether the responsiveness of T lymphocytes to mite allergen stimulation in vitro is a determinant of bronchial response to house dust mite (HDM) allergen challenge in subjects who are allergic to HDM.
Peripheral blood was taken from seven healthy nonatopic subjects and 23 subjects with positive skin test reactions to HDM. Of the subjects in the latter group, 16 had an asthmatic reaction on inhalation challenge with HDM extract (HDM-responders), whereas the remaining seven had a negative reaction (HDM allergic). The proportion of subsets of T lymphocytes and their activation and the amount of IL-2, IL-4, IL-5, and interferon-gamma released in the supernatants with and without stimulation with the HDM extract were determined.
Without stimulation, the proportions of subsets of T lymphocytes and their activation were similar between groups. When stimulated with the HDM allergen, the proportion of CD4+CD25+ cells from HDM responders was significantly higher than those in the control group. Comparison within groups of cell cultures with and without stimulation with the mite allergen showed that the proportion of CD4+, CD4+CD25+, CD4+/CD8+, and CD3+HLADR+ cells were significantly increased in HDM responders with stimulation; there was a trend for CD4+CD25+ cells to be increased in the HDM-allergic subjects; no increase in any T-lymphocyte subsets was found in the control subjects. The release of IL-5 was significantly greater in HDM responsers than in the other two groups. The severity of the immediate asthmatic reaction was significantly associated with the degree of nonallergic bronchial hyperresponsiveness and the amount of IL-5 released but not with the level of specific IgE to the mite allergen or subsets of T lymphocytes with and without stimulation.
The findings suggest that responsiveness of T lymphocytes to allergen challenge in vitro may play a role in determining the bronchial response to the allergen in vivo.
有大量证据表明T细胞可能在哮喘中起重要作用。本研究的目的是确定对屋尘螨（HDM）过敏的受试者中，T淋巴细胞在体外对螨过敏原刺激的反应性是否是支气管对HDM过敏原激发反应的决定因素。
采集7名健康非特应性受试者和23名HDM皮肤试验反应阳性受试者的外周血。在后一组受试者中，16名在吸入HDM提取物激发试验时有哮喘反应（HDM反应者），而其余7名反应阴性（HDM过敏者）。测定有无HDM提取物刺激时T淋巴细胞亚群的比例及其活化情况，以及上清液中释放的白细胞介素-2（IL-2）、白细胞介素-4（IL-4）、白细胞介素-5（IL-5）和干扰素-γ的量。
未刺激时，各组间T淋巴细胞亚群的比例及其活化情况相似。用HDM变应原刺激时，HDM反应者的CD4+CD25+细胞比例显著高于对照组。在有或无螨变应原刺激的细胞培养组内比较显示，HDM反应者刺激后CD4+、CD4+CD25+、CD4+/CD8+和CD3+HLADR+细胞比例显著增加；HDM过敏受试者中CD4+CD25+细胞有增加趋势；对照组中任何T淋巴细胞亚群均未增加。HDM反应者中IL-5的释放显著高于其他两组。速发型哮喘反应的严重程度与非过敏性支气管高反应性程度和IL-5释放量显著相关，但与对螨变应原的特异性IgE水平或有无刺激时的T淋巴细胞亚群水平无关。
研究结果表明，T淋巴细胞在体外对变应原激发的反应性可能在决定体内支气管对变应原的反应中起作用。
