ABSTRACT
Objective To explore the way and technique to gain adequate seed cells for skin tissue engineering sufficiently. Methods Human telomerase reverse transcriptase (hTERT) gene was introduced into rabbit keratinocytes by eukaryotic vector. The positive clones were selected and cultured in microcarrier-RCCS. The growth of immortalized keratinocytes was observed, and the metabolic rate and pan-cytokeratins (AE1/AE3) expression of immortalized keratinocytes in experimental groups were detected and compared with those in the control group. Results The immortalized keratinocytes in the experimental groups grew rapidly and had a high metabolic rate and shorter population doubling time (PD) (P
ABSTRACT
Objective To study histologic characteristics of bilayer skin substitute reconstructed by cells from human hair follicle and whether the skin appendage can be induced based on the bilayer skin substitute.Methods After composite chitosan bilayer skin substitute was reconstructed with dermal papilla cells and outer root sheath cells or dermal sheath cells and outer root sheath cells,its histologic characteristics was investigated in vitro and after transplanted onto SD albino rats.Results Composite chitosan bilayer skin substitute reconstructed by cells from hair follicle had closely arranged epithelium cells and outstanding cornification;Epithelial cords linked with epidermis could be seen in dermis.However,there was no certain hair follicle-like structure formation either in vitro or in vivo.Conclusion Hair follicle cells are good source for skin substitute reconstruction,but it can not induce skin appendage formation through skin substitute by now.
ABSTRACT
Although the research work on the permanent skin substitutes was started in our country later than in developed countries, the development has been promising in recent years. The results of this field of research would completely change the fact that deep burn wounds could only be repaired with autologous skin grafting. It is our expectation that with the advent of these permanent skin substitutes, the survival rate of severe trauma could be raised and the quality of wound repair could be improved. In a series of papers published in this issue, the development and the status quo of permanent skin substitutes will briefly be introduced.
ABSTRACT
To reconstruct a composite skin substitute composed of keratinocytes and collagen sponge as dermal scaffold. Collagen was extracted from fresh porcine skin. After being mixed with chondroitin sulfate, it was frozen and dried under vacuum to form a spongy membrane. Keratinocytes were separated from the foreskin with the routine method, and they seeded on the collagen membrane. The keratocytes which were carried by the collagen sponge were cultured, and the growth and proliferation were observed. The result showed that keratinocytes could grow and proliferate to form a confluent layer after 2～3 weeks. It indicated the the collagen sponge membrane showed no toxicity to human epidermal cells, and it could be used as a dermal scaffold in the construction of a composite skin substitute.
ABSTRACT
This study was aimed to improve the therapeutic results of composite skin substitutes. Human vascular endothelial cell growth factor (hVEGF 165 ) gene was constructed to an eukaryotic expression vector pcDNA3. Transfection of recombinant vector pcDNA3 hVEGF 165 into human dermal fibroblast cells was performed. VEGF protein level in the supernatant of transfected fibroblasts culture was determined. Its biological activities were tested by observing the growth rate of the human umbilical vein endothelial cells/HUVEC after being stimulated with the said supernatant, and by performing the Miles assay in guinea pigs. The results showed that these transgenic cells were able to secrete VEGF to certain extent, with biological activities to enhance the growth of HUVEC in vitro and improve vascular permeability. It indicated that transgenic fibroblasts could resurface the dermal substitute of a composite skin.