In vivo detection of human vascular endothelial growth factor promoter activity in transgenic mouse skin

Am J Pathol. 2000 Jul;157(1):103-10. doi: 10.1016/S0002-9440(10)64522-1.

Abstract

We have generated transgenic mice expressing green fluorescent protein (GFP) driven by 2.453-kb (-2,362 to +91) of the 5'-upstream region of the human vascular endothelial growth factor (VEGF) promoter to monitor changes of VEGF gene transcription in situ. Neonatal transgenic mice exhibited GFP-derived fluorescence in tissues that have been previously reported to express VEGF mRNA expression, including lung, cartilage, and brain. In normal skin during postnatal development, moderate fluorescence was observed in the upper epidermis and, more prominently, in the outer root sheath keratinocytes of hair follicles. Strong up-regulation of GFP fluorescence was observed in the hyperplastic epidermis of the wound edge at 48 hours after wounding, whereas little GFP fluorescence was detected in the dermis. In situ hybridization confirmed an identical expression pattern of VEGF mRNA in these wounds. Topical application of 12-O-tetradecanoylphorbol-13-acetate (TPA) induced strong VEGF-GFP expression in suprabasal epidermis. Little or no fibroblast-derived fluorescence was seen both in the wound model and after TPA application. By confocal laser microscopy, increased GFP fluorescence was detectable in the epidermis of intact mouse ear skin as early as 6 hours after topical TPA treatment. Importantly, GFP fluorescence was also measurable in the skin of living transgenic mice. These results resolve the present controversy regarding the ability of VEGF-GFP transgenic mouse models to correctly reflect established patterns of VEGF expression, and show the model to be a powerful tool for the in vivo monitoring of VEGF gene expression.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Cells, Cultured
  • Dermis / cytology
  • Dermis / metabolism
  • Endothelial Growth Factors / genetics*
  • Epidermal Cells
  • Epidermis / metabolism
  • Fibroblasts / cytology
  • Fibroblasts / metabolism
  • Gene Expression
  • Gene Expression Regulation / drug effects
  • Green Fluorescent Proteins
  • Humans
  • Keratinocytes / cytology
  • Keratinocytes / metabolism
  • Luminescent Proteins / drug effects
  • Luminescent Proteins / genetics
  • Luminescent Proteins / metabolism
  • Lymphokines / genetics*
  • Mice
  • Mice, Inbred C57BL
  • Mice, Inbred DBA
  • Mice, Transgenic
  • Promoter Regions, Genetic / genetics*
  • Recombinant Fusion Proteins / drug effects
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / metabolism
  • Skin / cytology
  • Skin / metabolism*
  • Tetradecanoylphorbol Acetate / pharmacology
  • Vascular Endothelial Growth Factor A
  • Vascular Endothelial Growth Factors
  • Wound Healing

Substances

  • Endothelial Growth Factors
  • Luminescent Proteins
  • Lymphokines
  • Recombinant Fusion Proteins
  • Vascular Endothelial Growth Factor A
  • Vascular Endothelial Growth Factors
  • Green Fluorescent Proteins
  • Tetradecanoylphorbol Acetate