P4 RELATIVE CELLULAR MIGRATION RATES OF MATCHED HUMAN SCALP FOLLICULAR AND INTERFOLLICULAR FIBROBLASTS USING THE MONOCULTURE "SCRATCH ASSAY"
Karoo ROS, Nelson L, Kauser S, Sharpe DT, Tobin DJ
Medical Biosciences, School of Life Sciences, University of Bradford, United Kingdom

It is well documented that the hair follicle's outer root sheath (ORS) is involved in epidermal repair and regeneration following wounding. With structural parallels between the ORS and the Dermal Sheath (DS) it has been extrapolated that the DS may provide a dermal equivalent in response to injury by providing fibroblasts to the dermis. Hair follicle DS cells express high levels of a-smooth muscle actin (a-SMA) in vivo and in vitro and is also present in wound-healing fibroblasts (myofibroblasts) where it thought to contribute to cellular motility. The aim of the current study was to assess the relative migration into a zone of injury human of DS, Dermal Papilla (DP) and Interfollicular or Dermal Fibroblasts (DF). Matched sets of human DS, DP and DF were established from three healthy donors and cultured under similar conditions with RMPI 1640 medium supplemented with 10% fetal calf serum. Cell monolayers were mechanically injured with a longitudinal scratch by a sterile cell scrapper. Time-lapse photography was employed to measure the rate of "wound" closure and a measure of the advancing "wound edge" was taken for each cell type in each matched set at time points 9, 18, 24, 36 hours. Results of this study showed that at 18 and 24 h significantly greater "wound closure" rates were observed for DS compared to DP (p=0.001 at 18h) and for DF compared to DP (p=0.014 at 24h). Furthermore, at 36 h rate of "wound closure" was significantly greater for DS than DF's (p=0.05). In conclusion, these variable rates of cell migration among scalp fibroblasts may be directly related to the relatively greater level of a-SMA in the DS cells compared to DF and DP cells. This study demonstrates the migration potential of the DS cells into a zone of injury and their possible involvement in healing.