Changes of MMP-1 and TIMP-1 Expression in a Nude Mouse Model of Transplanted Human Skin During the Process of Burn Wound Healing and Hypertrophic Scar Forming / 中国医师杂志

ABSTRACT

Objective To explore the effect of MMP-1, TIMP-1 on burn wound healing and hypertrophic scar (HS) forming. Methods Normal human full-thickness skin grafts were transplanted to the back of nude (athymic) mice, after these grafts survived, deep Ⅱ degree burn wounds were made in the middle of these grafts. During the process of burn wound healing and HS formation, the expressions of MMP-1 and TIMP-1 were detected by immunohistochemical staining. Results MMP-1 expression was first noted by day 2 after burns and became more prominent from day 3 to day 15, and then decreased rapidly. Immunostaining for MMP-1 was markedly increased at boundary regions marked by connective tissue fluidity. Immunoreactive TIMP-1 was also detected by day 2 but rapidly assumed the same interface expression pattern as described for MMP-1. Compared with MMP-1, immunostaining of TIMP-1 was irregular, but was obvious around vascular tissues. Conclusions The balance between MMP-1 and TIMP-1 during the inflammation and granulation phases might be important for the regulation of collagen proteins degradation. Within the remodeling phase, the inhibition of MMP-1 by TIMP-1 and the decrease of collagen degradation might lead to HS forming. The striking immunolocalization of MMP-1 and TIMP-1 to epithelial-dermal, eschar-dermal, and vascular-dermal interfaces suggested that they might play a particularly significant role at boundary regions marked by connective tissue fluidity.