Protease Indicator for Chronic Wound Management

描述（由申请人提供）：慢性伤口的特征在于多形核白细胞（PMN）的过度存在，其产生过量的弹性蛋白酶和PMN胶原酶MMP-8。胶原酶破坏伤口基质，而弹性蛋白酶降解生长因子及其受体位点。这些过量的蛋白酶可以通过伤口的根治性外科清创术来降低以促进愈合。一旦伤口蛋白酶降低，宿主生长因子将发挥功能和/或临床医生可以向伤口添加外源性生长因子而不被这些有害酶降解。最近，已经开发了蛋白酶螯合敷料以降低蛋白酶含量以改善愈合。然而，确定蛋白酶水平已经降低需要对伤口流体或活组织检查进行实验室研究，在将信息返回给临床医生之前至少延迟24小时。使用本提案中开发的方法，可以对胶原酶和弹性蛋白酶进行快速、安全、廉价的床边测量，这将确定何时可以安全地停止使用蛋白酶螯合敷料。目前，更换另一种敷料的决定是通过简单地观察伤口的外观来做出的。将评估2种方法。第一种方法将是使用快速免疫层析方法测定两种蛋白酶。第二种方法是通过快速比色法或荧光法测定弹性蛋白酶。将使用纯化蛋白、人工伤口液和患者伤口液样本对方法进行验证。用于开发本产品的试验是标准的，应在II期研究中进行商业产品开发。器械的商业生产和FDA批准应该是直接的。生产成本低，因此，广泛的用途和公司利润预计。对我们的慢性伤口患者群体的益处应该是显著的。

DESCRIPTION (provided by applicant): Chronic wounds are characterized by an overabundant presence of polymorphonuclear leukocytes(PMN's) which produce excessive elastase and the PMN collagenase , MMP-8. Collagenase destroys the wound matrix while elastase degrades growth factors and their receptor sites. These excessive proteases can be lowered by radical surgical debridement of the wound to promote healing. Once the wound proteases are lowered, host growth factors will be functional and/or the clinician can add extrinsic growth factors to the wound without degradation by these deleterious enzymes. More recently, protease sequestering dressings have been developed to lower protease content for improved healing. However, determination that the protease level has been lowered requires laboratory study of wound fluids or biopsies with at least a 24 hour delay before the information is returned to the clinician. Using the methodology to be developed in this proposal, a rapid, safe, inexpensive bed-side measurement of collagenase and elastase can be made which will determine when the protease sequestering dressing can be stopped safely. At present, the decision to change to another form of dressing is made imperically by simply observing the appearance of the wound. 2 approaches will be evaluated. The first approach will be to assay both proteases using rapid immunochromatographic methods. The second approach will be to assay elastase by a rapid colorimetric or fluorometric method. The methods will be validated using purified proteins, artificial wound fluids, and patient wound fluid samples. The assays used to develop this product are standard and should lead to a commercial product development in a Phase II study. Commercial production of the device and FDA approval as such should be straight forward. Cost of production will be low and therefore, broad usage and company profit is expected. The benefits to our patient population with chronic wounds should be significant.