Kowal K, Pampuch A, Kowal-Bielecka O, DuBuske L M, Bodzenta-Łukaszyk A
Immunology Research Institute of New England, Gardner, MA, USA.
Clin Exp Allergy. 2006 Apr;36(4):426-32. doi: 10.1111/j.1365-2222.2006.02446.x.
Animal models of allergic asthma indicate that intravascular platelet activation is necessary for the development of allergen-induced chronic airway inflammation.
To evaluate whether the development of a late asthmatic response (LAR) in allergic asthma patients challenged with a relevant allergen is consequent to platelet activation.
Thirty-three house dust mite sensitive asthmatic patients were challenged intrabronchially with Dermatophagoides pteronyssinus (Dp) extract. Twelve non-atopic healthy subjects (HC) were used as controls. Platelet count and plasma levels of beta-thromboglobulin (beta-TG), platelet factor-4 (PF-4) and soluble P-selectin (sP-selectin) were assessed before the challenge (T(0)) and 30 min (T(EAR)), 6 h (T(LAR)) and 24 h (T(24)) after the challenge.
Eleven patients responded to allergen challenge with an isolated early asthmatic response (single responders, SR). In 22 patients dual asthmatic response was demonstrated (dual responders, DR). At T(0) neither the platelet count nor the mean plasma level of beta-TG in DR or SR were different from HC, the mean plasma level of PF-4 in SR was significantly greater than in HC (P=0.01) or DR (P=0.001), the mean plasma level of sP-selectin was significantly greater in DR than in HC (0.0002) but not statistically different from SR (P=0.055). A significant decrease in the platelet count and increase in the plasma level of all the studied markers was seen at T(EAR), which was followed by a gradual return to the baseline values in the SR. Elevated plasma levels of platelet activation markers and decreased platelet count were seen in the DR even at T(24). Strong correlation was found between the increase in plasma concentration of beta-TG at T(EAR) and the maximum fall in forced expiratory volume in 1 s at T(LAR) (r=-0.57; P=0.0006).
In allergic asthma patients development of prolonged airway inflammation after allergen challenge is associated with intravascular platelet activation.
过敏性哮喘动物模型表明，血管内血小板活化是变应原诱导的慢性气道炎症发展所必需的。
评估变应原激发的过敏性哮喘患者迟发性哮喘反应（LAR）的发生是否与血小板活化有关。
33例对屋尘螨敏感的哮喘患者经支气管内给予尘螨提取物（Dp）。12名非特应性健康受试者（HC）作为对照。在激发前（T(0)）以及激发后30分钟（T(EAR)）、6小时（T(LAR)）和24小时（T(24)）评估血小板计数以及β-血小板球蛋白（β-TG）、血小板因子4（PF-4）和可溶性P-选择素（sP-选择素）的血浆水平。
11例患者对变应原激发仅出现早期哮喘反应（单一反应者，SR）。22例患者表现出双重哮喘反应（双重反应者，DR）。在T(0)时，DR或SR的血小板计数以及β-TG的平均血浆水平与HC无差异，SR中PF-4的平均血浆水平显著高于HC（P = 0.01）或DR（P = 0.001），DR中sP-选择素的平均血浆水平显著高于HC（0.0002），但与SR无统计学差异（P = 0.055）。在T(EAR)时，血小板计数显著降低，所有研究标志物的血浆水平升高，随后SR中的这些指标逐渐恢复至基线值。即使在T(24)时，DR中仍可见血小板活化标志物的血浆水平升高以及血小板计数降低。T(EAR)时β-TG血浆浓度的升高与T(LAR)时第一秒用力呼气量的最大下降之间存在强相关性（r = -0.
