Our long-term goal is to develop gene transfer based treatment strategies to completely correct the wound healing impairment in diabetes. The overall objective of this proposal is to understand the mechanisms by which dermal-epidermal interactions normally induce the process of re- epithelialization in wound healing, how this process is disregulated in diabetic wound healing, and how over-expression of PDGF-B can """"""""jump start"""""""" dermal-epidermal interactions restoring the wound healing process. Based on preliminary work at our laboratory we have developed the overall working hypothesis that: diabetic wounds have disordered dermal-epidermal interactions lacking the normal level and sequence of growth necessary for the orderly progression of wound healing and this disordered dermal-epidermal interaction is corrected by PDGF-B over- expression-induced growth factors made by fibroblasts which accelerate keratinocyte proliferation and migration. To investigate this hypothesis we plan experiments with the following specific aims: I. To test the hypothesis that the mechanisms by which PDGF over-expression induces dermal signaling to the epidermis is mediated by induction of PDGF-A in dermal fibroblasts; II. To test the hypothesis that one mechanism by which PDGF over-expression induces dermal signaling to the epidermis is mediated by induction of PDGF-A in dermal fibroblasts; II. To test the hypothesis that one mechanism by which PDGF-B over-expression corrects diabetic impaired keratinocyte migration and proliferation is the induction of TGF-alpha expression in dermal fibroblasts; III. To test the hypothesis that another mechanism by which PDGF-B over-expression corrects-epidermal interactions in diabetes impaired re-epithelialization is by inducing production of fibronectin by dermal fibroblasts and alpha5bneta1 integrin expression in keratinocytes. We will use a combination in vivo models of diabetic impaired wound healing including the db/db mouse model, non-obese diabetic mice, and streptotozocin-inducing diabetes in TGF-alpha knock out mice. In addition, in vitro techniques using transwell, co-culture and organotypic skin reconstruct models will be used. We will analyze the effects of growth factor over-expression by standard history, immunocytochemistry, in situ hybridization, immunofluorescent staining and confocal microscopy, PCR, RT-PCR, Western blot, and ELISA. The results of these studies will have direct bearing on the translation of adenoviral mediated gene transfer strategies to the treatment of non- healing diabetic foot ulcers with the potential to ameliorate one of the most common complications of this disease.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
Research Project (R01)
Project #
1R01DK059242-01
Application #
6311288
Study Section
Special Emphasis Panel (ZDK1-GRB-3 (O2))
Program Officer
Jones, Teresa L Z
Project Start
2000-09-30
Project End
2005-08-31
Budget Start
2000-09-30
Budget End
2001-08-31
Support Year
1
Fiscal Year
2000
Total Cost
$322,500
Indirect Cost
Name
Children's Hospital of Philadelphia
Department
Type
DUNS #
073757627
City
Philadelphia
State
PA
Country
United States
Zip Code
19104
Keswani, Sundeep G; Balaji, Swathi; Katz, Anna B et al. (2015) Intraplacental gene therapy with Ad-IGF-1 corrects naturally occurring rabbit model of intrauterine growth restriction. Hum Gene Ther 26:172-82
Keswani, Sundeep G; Balaji, Swathi; Le, Louis D et al. (2013) Role of salivary vascular endothelial growth factor (VEGF) in palatal mucosal wound healing. Wound Repair Regen 21:554-62
Keswani, Sundeep G; Balaji, Swathi; Le, Louis et al. (2012) Pseudotyped AAV vector-mediated gene transfer in a human fetal trachea xenograft model: implications for in utero gene therapy for cystic fibrosis. PLoS One 7:e43633
Keswani, Sundeep G; Balaji, Swathi; Le, Louis et al. (2012) Pseudotyped adeno-associated viral vector tropism and transduction efficiencies in murine wound healing. Wound Repair Regen 20:592-600
Keswani, Sundeep G; Le, Louis D; Morris, Lee M et al. (2011) Submucosal gland development in the human fetal trachea xenograft model: implications for fetal gene therapy. J Pediatr Surg 46:33-8
Katz, Anna B; Keswani, Sundeep G; Habli, Mounira et al. (2009) Placental gene transfer: transgene screening in mice for trophic effects on the placenta. Am J Obstet Gynecol 201:499.e1-8
Javazon, Elisabeth H; Keswani, Sundeep G; Badillo, Andrea T et al. (2007) Enhanced epithelial gap closure and increased angiogenesis in wounds of diabetic mice treated with adult murine bone marrow stromal progenitor cells. Wound Repair Regen 15:350-9
Parvadia, Jignesh K; Keswani, Sundeep G; Vaikunth, Sachin et al. (2007) Role of VEGF in small bowel adaptation after resection: the adaptive response is angiogenesis dependent. Am J Physiol Gastrointest Liver Physiol 293:G591-8
Keswani, Sundeep G; Crombleholme, Timothy M (2004) Gene transfer to the tracheobronchial tree: implications for fetal gene therapy for cystic fibrosis. Semin Pediatr Surg 13:44-52
Keswani, Sundeep G; Katz, Anna B; Lim, Foong-Yen et al. (2004) Adenoviral mediated gene transfer of PDGF-B enhances wound healing in type I and type II diabetic wounds. Wound Repair Regen 12:497-504

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