Early gene expression profile of human skin to injury using high-density cDNA microarrays

Disturbances in normal wound healing may be traced to perturbations in gene expression following injury. To decipher normal and abnormal genetic responses to cutaneous injury, baseline gene expression of uninjured skin and injured skin must be better defined. Our aim for this study was to determine the gene expression profile of human skin immediately following injury using cDNA microarrays. Samples of normal and injured skin were obtained from 5 healthy females undergoing breast reduction surgery. Specimens of the epidermis and dermis were obtained at 30 minutes and 1 hour after the initial injury. RNA was extracted, reverse transcribed into cDNA and hybridized onto high-density cDNA microarray membranes of 4,000 genes. At 30 minutes, injury resulted in a consistent increase (> 2x) in gene expression of 124 out of 4,000 genes (3%). These genes were primarily involved in transcription and signaling. None of the 4,000 genes were decreased (< 2x) at 30 minutes. At 1 hour only 46 out of the 4,000 genes were increased in expression (1.15%) but 264 out of 4,000 (6.6%) genes were decreased greater than 2 fold, indicating a silencing of many structural genes. We have identified several genes, namely, suppressor of cytokine signaling-1, rho HP1, and BB1, that are highly expressed after injury and may have an unappreciated role in regulating the initial inflammatory response. These data provide an initial high-throughput analysis of gene expression immediately following human skin injury and show the utility and future importance of high-throughput analysis in skin biology and wound repair.