Akers S, Kucich U, Swartz M, Rosen G, Glass M, Rosenbloom J, Kimbel P, Weinbaum G
Department of Medicine, Graduate Hospital, University of Pennsylvania, Philadelphia.
Am Rev Respir Dis. 1992 May;145(5):1077-81. doi: 10.1164/ajrccm/145.5.1077.
One prediction of the protease-antiprotease hypothesis of chronic obstructive pulmonary disease (COPD) pathogenesis is the appearance of elastin-derived degradation products in the plasmas of affected patients that are due to the breakdown of alveolar interstitial elastin by an excess of elastolytic activity in the lung. We previously demonstrated a significant elevation of plasma elastin-derived peptides (EDP) in subjects with COPD in comparison with asymptomatic smokers with normal spirometry or normal nonsmokers. To better determine the selectivity of the assay for EDP as a marker of COPD, we measured plasma EDP levels in different patient populations. These included subjects with COPD, subjects with diseases that may involve accelerated elastolysis (pneumonia, atherosclerotic vascular disease, and inflammatory arthritis), subjects with diseases hypothesized to involve pulmonary inflammation without elastolysis (asthma and acute tracheobronchitis), asymptomatic smokers with normal spirometry, and healthy, nonsmoking subjects. Mean plasma EDP levels in subjects with COPD were elevated above those in all other subjects (p less than 0.01). The prospective analyses of specificity and sensitivity of plasma EDP levels as markers of COPD gave values of 91 and 65%, respectively. Utilizing receiver operating characteristic curve analysis to assess the diagnostic and screening performance of plasma EDP as a test for COPD (perfect test equals an area under the curve of 1.0), the area under the curve was 0.87, which compares favorably with many widely used clinical tests. These data demonstrate that the assay for plasma EDP is a quantitative, easily measured, and highly specific marker for subjects with COPD.
慢性阻塞性肺疾病（COPD）发病机制的蛋白酶-抗蛋白酶假说的一个预测是，受影响患者的血浆中会出现弹性蛋白衍生的降解产物，这是由于肺部弹性蛋白酶活性过高导致肺泡间质弹性蛋白分解所致。我们之前证明，与肺活量测定正常的无症状吸烟者或正常非吸烟者相比，COPD患者血浆弹性蛋白衍生肽（EDP）显著升高。为了更好地确定EDP检测作为COPD标志物的选择性，我们测量了不同患者群体的血浆EDP水平。这些群体包括COPD患者、可能涉及加速弹性蛋白分解的疾病（肺炎、动脉粥样硬化性血管疾病和炎性关节炎）患者、假定涉及无弹性蛋白分解的肺部炎症的疾病（哮喘和急性气管支气管炎）患者、肺活量测定正常的无症状吸烟者以及健康非吸烟者。COPD患者的平均血浆EDP水平高于所有其他受试者（p<0.01）。血浆EDP水平作为COPD标志物的特异性和敏感性的前瞻性分析结果分别为91%和65%。利用受试者工作特征曲线分析来评估血浆EDP作为COPD检测方法的诊断和筛查性能（完美检测的曲线下面积等于1.0），曲线下面积为0.87，与许多广泛使用的临床检测方法相比具有优势。这些数据表明，血浆EDP检测对于COPD患者是一种定量、易于测量且高度特异的标志物。
