Objective To introduce the basic research and cl inical potential of the hair foll icle stem cells related signal transduction in prol iferation and differentiation. Methods The recent original articles about the hair foll icle stem cells were extensively reviewed. Results Many different signal pathways had been involved in the skin development and self-newals.The hair foll icle stem cells could play an important role in the skin self-renewal and regeneration which were modulated by several different signal pathways, which included bone morphogenetic protein/transforming growth factor β, Wnt, Notch and ectodysplasin A genes. Conclusion The hair foll icle stem cells may be a future approach to repair cutaneous wounds as a cell therapy．
Objective To investigate the effects of the nerve, endocrine, and immune factors on the process of wound healing and regeneration of the skin after injury and to review the research work in the past years in this area. Methods The prospective study was made to explore the relationship among the nerve, endocrine, immune factors, and skin tissue repair and regeneration, and to summarize the recent advance in this area. Results The nerve, endocrine, and immune factors played an important role in the repair and generation of the skin after injury. Conclusion As there has been fewer studies made in this field, we should reinforce the related basic research in this field.
Objective To introduce the related issues in the clinical translational application of adipose-derived stem cells (ASCs). Methods The latest papers were extensively reviewed, concerning the issues of ASCs production, management, transportation, use, and safety during clinical application. Results ASCs, as a new member of adult stem cells family, bring to wide application prospect in the field of regenerative medicine. Over 40 clinical trials using ASCs conducted in 15 countries have been registered on the website (http://www.clinicaltrials.gov) of the National Institutes of Health (NIH), suggesting that ASCs represents a promising approach to future cell-based therapies. In the clinical translational application, the related issues included the quality control standard that management and production should follow, the prevention measures of pathogenic microorganism pollution, the requirements of enzymes and related reagent in separation process, possible effect of donor site, age, and sex in sampling, low temperature storage, product transportation, and safety. Conclusion ASCs have the advantage of clinical translational application, much attention should be paid to these issues in clinical application to accelerate the clinical translation process.
Objective To investigated the distribution of epidermal stem cells in rat fullthickness wound tissues during the wound healing process and toelucidate the roles of epidermal stem cells in wound repair in vivo.Methods Eighty circular fullthickness wounds were produced on both sides of the back in 20 male Wistar rats labeled with BrdU 60 days previously (4 wounds in each rat). BrdU, β1 integrin and keratin 19 (K19) were employed to determine the epidermal stem cells with SP immunohistochemical methods, and the epithelialization wasdetermined with routine histological methods of HE staining on the 3rd, 7th, 14th, and 21st days after operation.Results No cells with positive immunostaining for β1 integrin, K19 and BrdU were found in granulation tissue of woundin both groups during the healing process. However, a few scattered β1 integrin and K19 positive cells were found within the stratum spinosum and stratum granulosum of the epidermis on the wound edges on the 3rd day post-injury. And these positive cells gradually became more and more in number, and mostly concentrated on the border of wound edges till the wounds healed. In addition, the number of positive cells for β1 integrin and K19 in the infected wounds was less than that in non-infected wounds. These positive cells for β1 integrin and K19 staining on the wound edge were also positively stained with BrdU in the cellular nuclei. Conclusion The above results indicate that ectopia of epidermal stem cells present a major function during wound epithelialization.
Objective To study the relationship between the adipose tissues and cutaneous morphogenesis on wound healing. Methods Adipose tissues’ participation in regulation of food intake, energy expenditure, fuel metabolism, and a variety of other physiological processes was reviewed in the latest literature. The wound healing was regulated by endocrine, paracrine, and adipocytederived molecules. Results Several factors secreted by adipose tissues (leptin, cytokines, growth factors, lipids, metallothioneins, ect) regulated wound healing. Conclusion Adipose tissues may play a vital role in the process of wound healing. Further understanding of the complex interaction between adipose cells and cutaneous morphogenesis is essential to explore the mechanism of wound healing.
Objective To review the advances in gene expression of marrow stromal cells(MSCs) in biological characteristic, differentiation, gene therapy, supporting hematopoiesis, inflammation reaction in wound repair.Methods The related articles in recent years were extensively reviewed.Results MSCs can express not only specific mRNA of mesodermal cells but also that of endodermal and ectodermal cell types on various differentiation conditions. When transfected or transducted, MSCs can steadily express many therapeutic transgenesin vitro or in vivo as well. Furthermore, they have the ability to support hematopoietic system and participate in the process of inflammation in wound repair.Conclusion MSCs are stem cells which have the characteristicof self renewing, multipotency and easy to expand in vitro. MSCs are ideal target cells for cell and gene therapies.
Objective To review the current condition of growth factors and their application to clinical treatment of acute and chronic wounds. Methods Data from the literature and Medline were analyzed according to their different uses in acute and chronic wounds. Their potential side-effects were studied. Results All data showed that wound healing time in acute and chronic wounds was accelerated and wound healing quality was improved after treatment with growth factors. No sideeffect was observed. Conclusion The efficacy and safety of growth factors in improving wound healing were confirmed. However, some reconsideration aboutpotential problems of growth factors must be made to apply them clinically in the future.
OBJECTIVE: To describe the concept of "un-controlled wound repair" and review its current progress in basic research and clinical treatment. METHODS: The literature review and comprehensive analysis methods were used in this study. RESULTS: The results showed that the normal wound repair and "un-controlled" wound repair had made big progress in cellular, molecular and genetic levels in recent years and these progresses had enhanced the treatment progress in clinic. CONCLUSION: All data indicate that the wound repair is made a big progress both in basic and clinic fields. New high techniques, such as clone, biochip and stem cell and their use will promote the deep study of "un-controlled" wound repair.
Objective In vivo, the microenvironment of epidermal stem cells (ESCs) is complex, and estrogen might be involved in the micro environment. To investigate the biological effects of estrogen on the prol iferation and migration of ESCs in vitro. Methods hESCs were isolated from normal human foreskin and cultured. The second generation of hESCs were identified with flow cytometry after being marked with integrin β1, cytokeratin 19 (CK19), CK14, and CK10 antigens.hESCs of 2 × 106 cell density were cultured with ESCs special medium supplemented with 0.1 nmol/L Diethylstilbestrol in group A (estrogen group), with ESCs special medium supplemented with 10 nmol/L Raloxifene hydrochloride in group B (ER blocking agent group), and with ESCs special medium in group C (control group), respectively. The 100 μm “scratch” wounds were created by scraping confluent hESCs plated on Petri dishes with a sterile pipette tip in vitro. The migrating cells from the wound edge were quantified at 24, 48, and 72 hours after incubation. The rates of wound heal ing were calculated by SigmaScan Pro 5.0 software at 72 hours. The prol iferating effect of estrogen on hESCs was determined with MTT method at 24, 48, 72, 96, and 120 hours. Results Cultured primary hESCs could adhere to the wall showing ovoid in shape and grew into colonies. Flow cytometry showed the positive results for integrin β1, CK19, and CK14 (with positive rate of 96.63%, 95.47%, and 94.27%, respectively) and the negative result for CK10 (with positive rate of 1.32%). In group A, the number of cells crossing the wound edge was more than those of group B and group C at 24, 48, and 72 hours. The rates of wound heal ing were 69.00% ± 0.05% in group A, 35.00% ± 0.05% in group B, and 48.00% ± 0.06% in group C at 72 hours, showing significant differences among groups (P lt; 0.05). The prol iferating speed of hESCs was significantly higher in group A than in groups B and C (P lt; 0.01), and significantly higher in group C than in group B (P lt; 0.01) at 24, 48, 72, 96, and 120 hours. Conclusion The estrogen can promote the prol iferation and migration of hESCs in vitro. It may be involved in many biological activity of skin.
Objective To investigate the possible signaling mechanisms by which recombinant human plateletderived growth factor (rhPDGF) accelerated healingof cutaneous wound in diabetic rats. Methods Four full-thickness skin woundswere incised in the back of 26 male Wistar diabetic rats. The wounded rats were divided into 3 groups (7 or 8 rats each group). One group without treatmentwas used as a control, and the other 2 groups were treated with rhPDGF at a dose of 7.0 μg/cm2 wound or vehicle (DMSO/09% NaCl, vol/vol 1∶1) from 1 to14 days. The wound healing was evaluated by the measurements of the wound volume and area. Immunofluorescent and immunohistochemical staining were used to examine the phosphorylation of extracellular signalregulated kinase 1/2 (ERK1/2) andthe expression of proliferative cell nuclear antigen (PCNA), respectively. Results Granulation tissue appeared in the bed of wound after injury. The number of blood capillary buds and fibroblasts was greater in the rhPDGF-treated group than that in the other 2 groups. A lot of inflammatory cells infiltration and collagen deposition were observed in the wound. The wound-volume in the rhPDGF-treated group was smaller than that in control group (Plt;0.05). The reepithelialization rate in rhPDGF-treated group was higher than that inthe other 2 groups at 7 days after injury (Plt;0.05). The expression of PCNA in reparative cells was higher in rhPDGF-treated group than in control group or vehicle-treated group at 3,7 days after injury(Plt;0.05). The phosphorylation of ERK1/2 was ber in rhPDGF-treated group than that in control group or vehicle group at 7 and 14 days after injury(Plt;0.05). Conclusion These results suggest that rhPDGF accelerates wound healing and improves healing quality by increasingthe phosphorylation of ERK1/2.