Protease Indicator for Chronic Wound Management

描述(由申请人提供)：慢性创面的特征是多形核白细胞(PMN)过多，产生过多的弹性蛋白酶和PMN胶原酶，即基质金属蛋白酶-8。胶原酶破坏伤口基质，而弹性酶降解生长因子及其受体部位。这些过量的蛋白水解酶可以通过对伤口进行根治性清创来降低，以促进愈合。一旦伤口蛋白酶降低，宿主生长因子将发挥作用，和/或临床医生可以向伤口添加外源性生长因子，而不会被这些有害的酶降解。最近，蛋白酶隔离敷料已被开发出来，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液或活组织进行实验室研究，在将信息返回给临床医生之前至少要延迟24小时。使用本建议中开发的方法，可以进行快速、安全、廉价的胶原酶和弹性酶床边测量，以确定何时可以安全地停止蛋白酶隔离敷料。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。将对2种方法进行评估。第一种方法是使用快速免疫层析方法检测这两种蛋白水解酶。第二种方法是用快速比色法或荧光法测定弹性蛋白酶。这些方法将使用纯化的蛋白质、人工伤口液和患者伤口液样本进行验证。用于开发该产品的分析是标准的，应该会导致第二阶段研究中的商业产品开发。该设备的商业化生产和FDA的批准应该是直截了当的。生产成本将很低，因此，预计会有广泛的用途和公司利润。这对我们的慢性创面患者群体的好处应该是显著的。

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.