Background: Induced pluripotent stem cells (iPSCs) using 4 pluripotency transcription factor (c-myc, Klf, Oct-4, Sox) has turned skin fibroblasts into pluripotent stem cells. The aim of this study is to evaluate preputial skin regenerative capacity from three parameters: (i) epidermal cells proliferative capacity, (ii) presence of pluripotent stem cells in preputial skin, (iii) tissue repair prognosis in surgical incision margin.
Method: Design of this study is experimental study in accordance with ethical approval by ethical commission Faculty of Medicine Universitas Indonesia (FMUI)- Cipto Mangunkusumo National General Hospital. Ten post-circumscissed-preputial- skin samples were collected from mass circumscission under signed informed consent. This research is conducted in Jakarta from June 2014 to June 2015. The skin samples were transported in fixative solution to Histology Lab FMUI. After tissue processing, the samples were embedded in paraffin wax, sectioned by microtome and mounted on slides. The slides then underwent hematoxylin-eosin staining and immunohistochemistry specific for Ki-67 (cell proliferation marker), Oct4 (pluripotency marker), and tenascin-C (tissue repair marker). Mean of Ki-67+ cells was observed from five randomly selected high power fields (magnification 400x). Identification of Oct-4+ cells were documented from five randomly selected high power field (magnification 400x). For correlation with gross tissue repair, data was obtained from a follow up interview and physical observation.
Results and discussion: Mean of Ki-67 positive basal keratinocyte in inner mucosal epithelium was relatively higher than outer cutaneous epithelium (5.9 cells per high power field v/s 3.6 cells per high power field respectively). This indicates higher proliferative capacity in inner mucosa epidermal cells. 85.7% of tenascin-c positive samples exhibit normal inflammation resolution thus Tenascin-C may indicate normal tissue repair outcome. 8 out of 10 preputial skin samples had Oct4+ cells, specifically at sites previously reported as skin stem cell’s niche i.e. the sebaceous gland, hair root follicle, blood vessel lumen, and hypodermis layer of the skin.
Conclusion: Regenerative capacity of post circumcision preputial skin is indicated by higher proliferation activity in inner mucosa epidermal layer, normal tissue repair outcome as indicated by majority of Tenascin-C expression at wound incision area and presence of Oct-4+ cells in majority of post-circumcision preputial skin.