[A study on the detection of apoptosis of hypertrophic scar and its related modulating factors]

To investigate the relationships between the development of hypertrophic scar (HS) and apoptosis of fibroblast and endothelial cell, and to elucidate the influence of related modulating factors.

TUNEL and immunohistochemistry staining techniques were employed to examine apoptosis of fibroblast and endothelial cell. The expression of ICE and Bcl-2 in hypertrophic scar of 61 cases of postburn patients undergoing plastic surgery with HS and in 20 other operative patients with non-hypertrophic scars (NHS) was also determined.

The positive apoptotic cell indices of fibroblast and vascular endothelial cells during the proliferative stage of HS were 6.60 plus minus 4.43 and 8.90 plus minus 6.01 respectively, while those during the mature stage were 25.60 plus minus 5.70 and and 26.6 plus minus 6.02, respectively. There existed evident differences in positive apoptotic cell indices between the same kind of cells (fibroblasts or vascular endothelial cells) during the two stage (P < 0.01). The ICE positive expression rate in proliferative stage was much lower than that in mature stage (P < 0.01), but the Bcl-2 positive expression rate in proliferative stage was obviously higher than that in mature stage (P < 0.01).

HS development might be related to the decrement of apoptotic fibroblasts and endothelial cells. ICE and Bcl-2 were possibly involved in the modulation of fibroblast and endothelial cell apoptosis in HS.