Tissue Engineering for the Treatment of Delayed Healing

描述（由申请人提供）：慢性伤口的更有效的组织工程方法可能需要替换表型改变的伤口细胞，可能通过使用干细胞。使用绿色荧光蛋白（GFP）转基因小鼠和野生型小鼠，我们已经表明，输注GFP +骨髓细胞可以导致血管，角质形成细胞，和其他结构的生产在受伤的皮肤。我们利用常规尾巴的切除伤口开发的延迟愈合的新模型将使我们能够扩展这些观察。同时，我们发现局部应用自体骨髓来源的细胞，非愈合性人类慢性伤口显著愈合。我们提出了以下具体目标：1）使用GFP -骨髓细胞和骨髓细胞递送至伤口的不同方法来表征未分离的骨髓细胞在延迟愈合的鼠模型中的植入; 2）确定加速鼠伤口愈合的骨髓细胞亚群。我们将评估未分离的骨髓，以及Lin-和Lin+阳性骨髓细胞、间充质干细胞和造血干细胞，包括Lin-Sca+和Lin-Ho/10 Rho/10细胞。3)以评估骨髓衍生细胞的局部递送。体外和体内研究将确定在因子XIII交联的纤维蛋白凝胶中使用特定的骨髓来源的细胞的这种方法的可行性; 4）确定自体骨髓来源的细胞是否可以纠正慢性伤口的异常细胞表型。我们将骨髓细胞的特定亚群应用于不愈合的人类伤口，并将确定伤口成纤维细胞是否恢复愈合和正常表型。 这些研究将促进我们对如何重建伤口床以及是否有可能纠正不愈合伤口中异常细胞表型的理解。

DESCRIPTION (provided by applicant): A more effective tissue engineering approach to chronic wounds may require the replacement of phenotypically altered wound cells, possibly through the use of stem ceils. Using green fluorescent protein (GFP) transgenic and wild type mice, we have shown that infusion of GFP + marrow cells can result in the production of blood vessels, keratinocytes, and other structures in wounded skin. A new model of delayed healing we have developed using excisional wounds of routine tails will allow us to extend these observations. In parallel, we have found that non-healing human chronic wounds heal dramatically with the topical application of autologous bone marrow-derived cells. We propose the following specific aims: 1) to characterize the engraftment of unseparated marrow cells in a murine model of delayed healing using GFP - marrow cells and different methods of marrow cell delivery to wounds; 2) to determine the marrow cell subsets that accelerate healing in murine wounds. We will evaluate unseparated marrow, as well as Lin- and positive Lin+ marrow cells, mesenchymal stem cells, and hematopoietic stems cells, including Lin-Sca+ and Lin- Ho/l0Rho/10cells. 3) to assess the topical delivery of marrow-derived cells. In vitro and in vivo studies will determine the feasibility of this approach using specific marrow-derived cells in a Factor XIII cross-linked fibrin gel; 4) Determine whether autologous marrow-derived cells can correct the abnormal cellular phenotype of chronic wounds. We will apply specific subsets of marrow cells to non-healing human wounds and will determine whether healing and normal phenotype are restored in wound fibroblasts. These studies will advance our understanding of how to reconstitute the wound bed and whether it is possible to correct the abnormal cellular phenotype in non-healing wounds.