Expression data from the dermis of human established scars before and after hair follicle transplantation

Human hair follicles undergo repetitive cycles of growth throughout their lifetime. During the hair follicle cycle, functional and structural changes occur within the surrounding skin environment. However, skin that experienced a deep injury lacks cycling hair follicles and turns into a mass of unremodelled scar tissue. We hypothesise that re-introducing cycling hair follicles into human scars will stimulate skin remodelling improving fibrotic tissue. To determine the transcriptional events underlying remodelling of scar dermis after hair follicle transplantation, we used Affymetrix microarrays to perform profiling of scar dermis before (0 mo), and at three time points after hair transplantation transplantation: 2, 4, and 6 months. During the study, 3 mm punch biopsies were taken from the scar dermis from each patient at four time points: prior to transplantation (time point 0 mo), then again at 2, 4, and 6 months after hair follicle transplantation. The scar dermis was dissected from 20 µm-thick sections of the biopsies and RNA was isolated using RNeasy Plus Mini Kit (Qiagen). RNA was used to synthesize first-strand complementary DNA (cDNA) using Nugen Ovation V2. This was then converted to double-stranded cDNA, and used as a template for in vitro transcription to generate cRNA using the Nugen Encore Biotin Module. The cRNA was then transferred for hybridization and scanning onto the GeneChip™ Human Genome U133 Plus 2.0 Array. Transcriptomic Analysis Console (TAC) was used to perform a one-way ANOVA on the dataset to identify 719 transcripts that were significantly (P < 0.01) and differentially (fold change <- 1.5 or > 1.5) regulated the four time points (0 mo, 2 mo, 4 mo, 6 mo). We used Ingenuity Pathway Analysis (IPA) to find the upstream regulators of the transcriptomic changes in human scars after hair follicle transplantation at three time points: after 2, 4, and 6 months.