Abstract:

BACKGROUND: Chitosan and silk fibroin have its own merits and drawbacks, the co-culture of these two materials can improve performance. Studies with regard to co-culture of chitosan-silk fibroin scaffold and dermal mesenchymal stem cells (DMSCs) in vitro can provide a foundation for further engineering tissue construction. 
OBJECTIVE: To co-culture of chitosan-silk fibroin scaffold and rat DMSCs in vitro, and to explore the effects of chitosan-silk fibroin scaffold on the adherence, growth, and proliferation of DMSCs.
METHODS:  ① Chitosan was mixed with silk fibroin at ratio of 3:7, and then the mixture was prepared for chitosan-silk fibroin scaffold after freeze drying. The pore size and porosity of scaffold was measured. ② The scaffold was co-cultured with rat DMSCs, the cell growth, matrix formation, as well as the combination of cells and scaffold was observed under an inverted phase contrast microscope. In addition, the cell adherence rate was calculated at 6, 12, and 24 hours after digestion. The cell proliferation was detected by MTT at 2, 4, 6, 8, and 10 days after co-culture. The normal cultured cells without scaffold were served as controls. 
RESULTS AND CONCLUSION:  ① The uniformity distributed pores with sizes of 100-150 μm could be seen under microscopes, whose average porosity was 90.3%. ② The cell adherence rate exhibited a time increasing trend within 24 hours, which reached to 93% after 24 hours. It suggested that DMSCs adhered well on chitosan-silk fibroin scaffold. ③MTT results demonstrated that there had no significant difference between the experimental and control groups at each culture detection points. However, the proliferation of the control group was greater than that of the experimental group at days 2 and 4 after culture, which was conversely at 10 days after culture. Under an inverted phase contrast microscope, DMSCs grew well and secreted rich cell matrix on chitosan-silk fibroin scaffold. All results suggested that chitosan-silk fibroin scaffold is suitable for DMSCs culture in vitro.