Establishment and Validation of a Stable, Cell-Based Diabetic Wound Bioassay

Delayed skin wound healing and foot ulcers affect up to 15% of diabetic patients. This impaired skin wound healing has been attributed to changes in the cells of the skin which may be altered by the disease. Currently, no suitable diabetic wound model exists and so inadequate animal models and human testing are often undertaken. This project will develop a simple, reproducible, laboratory-based diabetic wound model system to permit rapid, low cost testing of materials, reagents and drugs and importantly reduce unnecessary animal experimentation. We have already isolated normal and diseased (diabetic) cells from patients, altered them so that they grow forever and identified diabetic wound disease marker genes. This new project will use these disease marker genes to develop a cell-based reporter system, enabling automated testing and pre-screening of reagents which may ameliorate the diabetic wound disease state. It is our aim to develop this bioassay commercially, producing a high-throughput screening system which will reduce the amount of unnecessary animal studies undertaken with respect to wound products/materials testing.

Chronic wounds, such as diabetic foot ulcers, result in impaired wound healing in 3-5% of the population over the age of 65. However, despite the increasing financial burden of these diabetic wounds there is, at present, no suitable diabetic chronic wound animal model. Therefore, in the light of the concerns and limitations of animal models and human testing, this NC3Rs Grant application will develop a stable, reproducible, in vitro diabetic wound model system. This will permit rapid, low cost testing of materials, reagents and drugs in order to reduce unnecessary animal experimentation. We have already demonstrated that venous leg ulcer derived fibroblasts (CWF) and diabetic foot ulcer fibroblasts (DF) are phenotypically distinct from patient-matched normal fibroblasts (NF). We have also immortalised both the NF and DF (by retroviral insertion of the human telomerase) to create stable, disease-specific cell lines and within these cells have identified disease specific marker genes by microarray analysis. The aim of this NC3Rs Grant application will be to extend these initial studies/findings and, using a virus integration approach, stably transduce our immortalised disease cells with fluorescent disease marker gene reporter constructs. This will give us a robust, cell-based reporter system, enabling automated testing and pre-screening of reagents which may ameliorate the diabetic wound disease state. It is anticipated that at the end of the funding we will be close to commercialising the bioassay and developing a high-throughput screening system, which will reduce the amount of unnecessary animal studies undertaken with respect to wound product/materials testing. We believe that the development of such an in vitro diabetic wound model will represent an important and unique resource for wound healing researchers Worldwide.