Objective      To evaluate the efficacy of the chitosan/alginate nanomembrane as cell scaffold material to enhance burn wound healing by promoting the adhesion

migration

proliferation and differentiation of mouse bone marrow mesenchymal stem cells (MSCs).        Method

s        BALB/c mice (aged 8 weeks) were selected as the experimental animals. A 5-mm diameter full-thickness cutaneous burn wound was inflicted on the depilated dorsal skin in each of mice. Then the animals were firstly divided into 2 groups. The wounds in experimental group were covered with the nanomembrane

while those in control group were not. Equal bone marrow-derived MSCs transduced with green fluorescent protein (GFP) gene were transplanted to the periphery of the skin wounds in both groups of mice. The intensity of the GFP signal was evaluated after surgery with an In Vivo Imaging system. Fluorescence activated cell sorting (FACS) was used to quantify the ratio of the positive GFP-MSCs. Frozen sections of the newly formed tissues were observed respectively to evaluate the survival condition of the GFP-MSCs. Then another groups of mice were divided into blank control group

nanomembrane group

MSCs injected group and nanomembrane+MSCs injected group (n=8). The condition of wounds healing in each group were observed and assessed at different time points after surgery.        Results        The expression of GFP was significantly higher in the experimental group than the control group on the 7th day after surgery [intensity of GFP signal (25.97±6.98)×10

4

vs (6.00±2.84)×10

4

P0.05

]

. Flow cytometry showed that the average percentage of the positive GFP-MSCs was obviously higher in experimental group than that in control group on the 5th day after surgery [(66.78±7.00)% vs (33.58±3.62)%

P0.01

]

and on the 7

th

day [53.03±3.15)% vs (34.20±7.98)%

P0.01

]

. Fluorescence microscopy indicated the density of GFP-MSCs in newly formed tissue was greater in experimental group than control group in 14 d after surgery [(101.00±15.51)/horizon vs (25.25±5.07)/horizon

P0.05

]

. The wounds of the namomembrane+MSCs group showed significantly faster healing speed than the other 3 groups (P0.05).       Conclusion        When applied in skin wounds

the chitosan/alginate nanomembrane promotes the a

dhesion

migration

proliferation and differentiation of MSCs

and can served as a good cell scaffold for reconstruction of skin tissue.