Mesenchymal stem/stromal cells (MSCs) as one of the most important types of adult stem cells secrete a variety of immunomodulatory cytokines. However, their immunomodulatory features strongly depend on the molecular cross-talk between cells and the surrounding microenvironment. Hence, some strategies were proposed to empower their beneficial effects during cell-therapeutic procedures to avoid confusing results. Licensing the cells with chemical compounds could be considered as one of the most applicable methods for induction of anti-inflammatory status in the cells. Human chorionic gonadotropin (hCG) is a pregnancy related hormone which has been shown to be essential for the establishment of a successful pregnancy. HCG supports the implantation of fetus in the maternal endometrium, due to its immunomodulatory effects. Moreover, the regulatory role of hCG has been previously mentioned in case of some autoimmune-based diseases. In the present study, the capacity of this hormone for induction of different immune-encountered genes expression was examined in primary cultures of human adipose tissue derived mesenchymal stem cells (Ad-MSCs). In this regard, Ad-MSCs were exposed to 10 IU of hCG for 72 hours. Molecular studies via quantitative Real-time PCR (qRT-PCR) experiments were performed to detect gene expression modifications based on the application of SYBR Green as the fluorescent dye and in comparison to the RPLP0 as the housekeeping gene. Results confirmed that hCG significantly upregulated TSG-6, TGF-β1, IL-1β and IL-6 expression levels comparing with the control group, while it downregulates COX-2 expression, and had no statistically significant effects on IL-10 andTDO2. In conclusion, priming Ad-MSCs with hCG may enhance the proliferation and immunoregulatory potential of these cells, although it needs further investigations to reveal involved molecular pathways.
Cutaneous wound healing is a complex type of biological event involving proliferation, differentiation, reprograming, trans/de-differentiation, recruitment, migration, and apoptosis of a number of cells (keratinocytes, fibroblasts, endothelial cells, nerve cells and stem cells) to regenerate a multi-layered tissue that is damaged by either internal or external factors. The exact regeneration mechanism of damaged skin is still unknown but the epithelial and other kinds of stem cells located in skin play crucial roles in the healing process. In this work, a co-culture model composed of adipose derived mesenchymal stem cells and keratinocytes was developed to understand the cellular differentiation behaviour in wound healing. Human mesenchymal stem cells were isolated from waste lipoaspirates. Keratinocytes were isolated from neonatal rats skin as well from human adult skin. Both types of cells were cultured and their culturing behaviour was observed microscopically under regular intervals of time. The identity of both cells was confirmed by flow cytometry and qRT-PCR. Cells were co-cultured under the proposed co-culturing model and the model was observed for 7, 14 and 21 days. The cellular behaviour was studied based on change in morphology, colonization, stratification, migration and expression of molecular markers. Expression of molecular markers was studied at transcriptional level and change in cellular morphology and migration capabilities was observed under the invert microscope regularly. Successfully isolated and characterized mesenchymal stem cells were found to express keratinocyte lineage markers i.e. K5, K10, K14, K18, K19 and Involucrin when co-cultured with keratinocytes after 14 and 21 days. Their expression was found to increase by increasing the time span of cell culturing. The keratinocyte colonies started to disappear after 10 days of culturing which might be due to stratification process initiated by possibly transdifferentiated stem cells. It can be concluded that mesenchymal stem cells can regenerate the damaged skin if transplanted to damaged area but for their successful differentiation and enhanced regeneration, they need a population of keratinocytes in situ which need further experiments for validation of co-culture model and its potential for being used in clinics.