Effect of skin autograft with different thickness on the transdifferentiation of fibroblasts after deep partial thickness burn in rats

Abstract

To investigate the effect of thin split-thickness skin, inter-mediate thickness skin and full-thickness skin autograft on the differentiation of fibroblasts into myofibroblasts in rats after deep partial thickness burn. A total of 40 SD rats were divided randomly into two groups (Group A & Group B, n = 20 each). In Group A, tissue samples were collected at Day 2 after skin-grafting while Day 7 in Group B. In each group, every rat was scalded to cause deep partial thickness wound with an area of 10% of total body surface. The wounds received eschar shaving instantly coupled with skin-autograft, covering with thin split-thickness skin, inter-mediate thickness skin and full-thickness skin respectively. Meanwhile the control wound on the same rat was scalded only. Then the expression of α-SMA was detected by immunohistochemistry in each wound. And the numbers of myofibroblasts (α-SMA positive cells) and fibroblasts (negative cells) were counted to calculate the conversion ratio of myofibroblasts. In Group A, the conversion ratios of myofibroblasts of control, thin split-thickness skin autograft, inter-mediate thickness skin and full-thickness skin groups were (76.3 ± 3.3)%, (69.8 ± 1.6)%, (57.5 ± 1.6)% and (44.7 ± 1.7)% respectively. In Group B, the ratios were (72.9 ± 6.1)%, (63.6 ± 4.7)%, (50.2 ± 1.6)% and (32.3 ± 1.2)% respectively. The ratio was higher in control group than that in any other one (P < 0.01). There was statistic difference between thin split-thickness skin, inter-mediate thickness skin and full-thickness skin autograft groups (P < 0.05). A direct association may exist between the conversion ratio of myofibroblasts and the application of skin-grafting in rats after deep partial thickness scalding. It is probably related with varying degrees of scar contracture in the long-term.