摘要
Objective:To explore the therapeutic mechanism of microporous sheep acellular dermal matrix(ADM)combined with human umbilical cord mesenchymal stem cell(hUCMSC)to promote the healing of full-thickness skin defect.Methods:hUCMSC was co-cultured on microporous sheep ADM to form composite biological dressings.Seventy-two nude mice were selected to make full-thickness skin injury models and randomly divided into 3 groups(hUCMSC+microporous sheep ADM group,sheep ADM group and iodophor gauze group),with 24 mice in each group.The wound healing rate of each group was detected at 14 d,21 d and 28 d after operation,qRT-PCR technique was used to detect the expression of Bax and Bcl-2 in the wound tissues,and the immunohistochemical staining technique was used to detect the expression of Collagen I and vascular endothelial growth factor(VEGF).Data were analyzed with one-way ANOVA and t test.Results:At 14 d after operation,the wound healing rate of the hUCMSC+microporous sheep ADM group was(65.34±14.72)%,which was significantly higher than that of the iodophor gauze group[(37.54±10.21)%],and higher than that of the sheep ADM group[(49.08±11.16)%],the differences were statistically significant(t=19.52,14.72;p<.05).With the gradual healing of the wound,at 28 d after operation,the wound healing rate of the hUCMSC+microporous sheep ADM group was(98.63±15.41)%,which was significantly higher than that of the iodophor gauze group[(81.74±16.27)%],and higher than that of the sheep ADM group[(63.47±14.80)%],the differences were statistically significant(t=-16.42,20.35;p<.05).The expression of Bax in the wound tissues of the hUCMSC+microporous sheep ADM group was significantly reduced,especially at 21 d after operation,the expression level was 0.25±0.06,which was significantly lower than the iodophor gauze group(0.53±0.16)and the sheep ADM group(0.41±0.12),the differences were statistically significant(t=3.52,-2.83;p<.05).The expression of Bcl-2 in the wound tissues of the hUCMSC+microporous sheep ADM group was significantly higher than those of the other two groups,especially at 21 d after operation,the expression level was 0.63±0.19,which was significantly higher than the iodophor gauze group(0.34±0.09)and the sheep ADM group(0.46±0.13),the differences were statistically significant(t=5.31,-6.07;p<.05).Immunohistochemical detection showed that the expression of Collagen I and VEGF in the hUCMSC+microporous sheep ADM group was slightly more than that of the sheep ADM group and the iodophor gauze group,but the effect was not remarkable.Conclusions:hUCMSC+microporous sheep ADM composite dressing can promote the healing of the full-thickness skin injury and reduce the production of apoptotic cells by carrying hUCMSC.
