哮喘联盟

   摘要
   包括基质金属蛋白酶（MMPs）在内的胞外蛋白酶被推测在如哮喘等慢性肺部疾病中发挥重要作用。尽管蛋白酶表达的增加与肺部发病相关，但局部酶活性和疾病进展之间的关系仍然知之甚少。我们报告MMP-2/9活化细胞穿透肽（ACPPs）和它们的比例类似物（RACPPs）用于在体内检测接受过过敏原卵清蛋白挑战小鼠的肺部蛋白酶活性和分布方面的应用。与对照小鼠相比，接受急性挑战的小鼠解剖肺中MMP-2/9的活性总体增加>2倍。（P=1.8×10-4）MMP-2/9活性的上调定位于炎症性气道的周围，这些炎症性气道的周围病态气道的蛋白酶高度依赖的ACPP的摄入是相邻的病理正常的肺实质的1.6倍。（P=0.03）MP-2/9的活性通过与明胶酶活性共定位的ACPP裂解进行探测，明胶酶的活性则通过DQ明胶原位酶谱分析方法检测。为了便于比较，分别通过弹性蛋白酶和凝血酶裂解RACPPs检测中性粒细胞弹性蛋白酶的活性和凝血酶活性，它们在接受急性过敏原挑战的小鼠肺部未显著升高。结果表明，活性MMP2/9和相关的ACPPs的蛋白酶活性可允许在小鼠哮喘模型中实时检测，象这样的ACPPs应该可以改善我们对蛋白酶活性在哮喘疾病进展中的了解，并有助于阐明新的治疗靶点或作为一种治疗性药物递送机制。
 

                                      （苏楠 审校）
Am J Physiol Lung Cell Mol Physiol. 2014 Feb 7. [Epub ahead of print]

 

Detection and monitoring of localized matrix metalloproteinase upregulation in a murine model of asthma.
 

Felsen CN, Savariar EN, Whitney MA, Tsien RY.
 

Abstract
Extracellular proteases including matrix metalloproteinases (MMPs) are speculated to play a significant role in chronic lung diseases such as asthma. Although increased protease expression has been correlated with lung pathogenesis, the relationship between localized enzyme activity and disease progression remains poorly understood. We report the application of MMP-2/9 activatable cell-penetrating peptides (ACPPs) and their ratiometric analogs (RACPPs) for in vivo measurement of protease activity and distribution in the lungs of mice that were challenged with the allergen ovalbumin. MMP-2/9 activity was increased > 2-fold in whole, dissected lungs from acutely challenged mice compared to control mice (p = 1.8x10-4). This upregulation of MMP-2/9 activity was localized around inflamed airways with 1.6-fold higher protease-dependent ACPP uptake surrounding diseased airways compared to adjacent, pathologically normal lung parenchyma (p = 0.03). MMP-2/9 activity detected by ACPP cleavage co-localized with gelatinase activity measured with in situ DQ gelatin. For comparison, neutrophil elastase activity and thrombin activity, detected with elastase- and thrombin-cleavable RACPPs, respectively, were not significantly elevated in acutely allergen challenged mouse lungs. MThe results demonstrate that ACPPs, like the MMP2/9-activated and related ACPPs, allow for real-time detection of protease activity in a murine asthma model, which should improve our understanding of protease activation in asthma disease progression and help elucidate new therapy targets or act as a mechanism for therapeutic drug delivery.
 

Am J Physiol Lung Cell Mol Physiol. 2014 Feb 7. [Epub ahead of print]