Objective To investigate the feasibility of transplantation of mesenchymal stem cell (aisc) into expanion skin. Methods MSCs were isolated from porker's bone marrow and cultured in vitro. Pigs were randomly divided into four groups: Group A was injected with MSCs on the local expansion; Group B was injected with MSCs from ear vein; Group C was planted expander only; Group D was the contronl group. Each side of pig's spinal column was implanted with three expander in groups A, B and C. The same volume of NS was injected at the fixed time, the marked area measured after 7, 14, 28 days of expansion, the difference of those area was compared between groups. The differentiation of BM-MSC was detected by immunofluorescence. Results Flow-cytometric analysis showed that these BMSCs expressed CD90 and CD29 highly but did not express CD34 or CD45. The expansion area (cm2) of groups A, B, C and D was 34.05±0. 92, 31.83±l. 07,30. 10±0.79, and 18. 27±0.25, respectively (P＜0. 01). Immunofluorescence showed that the positive expression rate of CD31, PCNA in groups A and B was higher than that in groups C and D, in which the expression was the highest in group A. Conclusions Allogeneic transplantation of BM-MSC can promote skin expansion and the effect of local transplantation group is most significant.

Objective: To investigate the effects of the repair and restitution of ear-shaped cartilage by adipose tissue-derived stem cells(ADSC) and cartilage acellular extracellular matrix. Methods: ADSC were extracted by digesting with collagenase type II from the adipose tissue from 32 patients with adiposity whose fats were drawn, and were cultured and subcultured in vitro. The natural biological scaffolds were prepared by acellular method using porcine ear cartilage, and then the second generation ADSC(5.0×10⁷/ml) were inoculated on the preformed natural bio-scaffold scaffold by culturing in vitro for 3 days to form a cell scaffold complex. 32 New Zealand white rabbits were randomly divided into the experimental groups, the control group A, the control group B and the control group C. All New Zealand white rabbits were modeled by ear cartilage defects. The cell scaffolds composite was implanted into the experimental group of the ear cartilage defects of rabbits, the ADSC were implanted into the control group A, the cartilage acellular extracellular matrix scaffold was implanted into the control group B and the control group C was modeled only by ear cartilage defects. After 16 weeks, the animals were sacrificed and the repair effect was observed by gross appearance and histological examinations including HE, Toluidine blue staining, Safranin O and typeⅡ collagen staining. Its were quantitatively analyzed by positive staining results of type Ⅱ collagen. Ear cartilage tissue elasticity was detected. SPSS 17.0 software was used to analyze the data. Results: The cartilage defects in the experimental group were repaired well by general shape observation and those in the control group was filled in with granulation tissue. There were significant differences between the experimental group and the control group in the wet weight(P<0.05). HE staining showed that cartilage cavities formed in articular cartilage defects, and only the fibrous tissue was filled with the ear cartilage defect in the control groups. In the repair area, Toluidine blue staining, Safranin O and type Ⅱ collagen staining were positive in the experimental group, and negative in the control groups. There was no significant difference between the experimental group and the normal ear cartilage in the ear cartilage elastic constant detection(P>0.05). Conclusions The mechanics and histology of rabbit ear neonatal cartilage constructed by ADSC combined with cartilage acellular matrix are close to normal ear cartilage. Cartilage acellular matrix material combined with adipose-derived stem cells has good repair and reconstruction ability for ear cartilage defects, which possesses potential clinical application value.