Tgf-beta antisense therapy increases angiogenic potential in human keratinocytes in vitro

BACKGROUND: Transforming growth factor-beta (TGF-beta) has been identified as an important component of wound healing. Recent developments in molecular therapy offer exciting prospects for the modulation of wound healing, specifically those targeting TGF-beta. The purpose of this study was to analyze the effect of TGF-beta targeting on the expression of angiogenic vascular endothelial growth factor (VEGF), a key regulator of angiogenesis, and in vitro angiogenic activity. METHODS: Expression of angiogenic VEGF in tissue samples from chronic dermal wounds was investigated by immunohistochemistry. The effect of TGF-beta targeting using antisense oligonucleotides on the expression of VEGF was analyzed by ELISA and RT-PCR in cultured human keratinocytes. Human endothelial cells (EC) were grown in conditioned medium produced from the treated keratinocytes. EC migration was measured using a modified Boyden chamber, EC tube formation was analyzed under the light microscope. RESULTS: Immunohistochemical investigation demonstrated a decreased expression of VEGF protein in tissue samples from chronic dermal wounds compared to normal human skin. Antisense TGF-beta oligonucleotide treatment upregulated VEGF secretion in vitro. Addition of conditioned medium from TGF-beta antisense-treated keratinocytes resulted in an increase of endothelial cell migration and tube formation. CONCLUSIONS: Our results demonstrate that TGF-beta antisense oligonucleotide technology may be a potential therapeutic option for stimulation of angiogenesis in chronic wounds.