Abstract:

BACKGROUND: Many studies focus on transforming growth factor β (TGF β) and its receptors, however, the distribution of type Ⅰ TGF receptor (TGF-βR Ⅰ) in peripheral region of hypertrophic scars remain poorly understood. 
OBJECTIVE: To determine the expression and distribution of TGF-βR Ⅰ and type Ⅰ collagen in the peripheral and central areas of human skin hypertrophic scar.
METHODS: A total of 30 cases with human cutaneous scars admitted at the Department of Plastic Surgery, First Affiliated Hospital and Department of Mammary Gland, Head and Neck Surgery, Tumor Hospital of Xinjiang Medical University from 1999 to 2002, were selected, including 20 cases with hypertrophic scar and 10 cases with normal scars. A total of 180 scars were obtained from central and peripheral areas of scars as well as normal skin tissues. The protein contents of TGF-βR1 and type Ⅰ collagen was detected by immunohistochemistry. In addition, the immunostaining positive in these samples was analyzed by semiquantitative analysis.
RESULTS AND CONCLUSION: Compared to non hypertrophic scar and normal skin tissues, the TGF-βR1 expression of hypertrophic scar was obvious greater with strong positive reaction. The TGF-β RⅠ content was 100% in peripheral region of hypertrophic scar, which was notably 20% greater than that of central area (P < 0.05). The content of type Ⅰ collagen was both 100% in peripheral and central areas. The differences of positive TGF-β  RⅠ and type Ⅰ collagen had no significance between peripheral and central areas of non hypertrophic scars (P > 0.05). There were few contents of TGF-β RⅠ and type Ⅰ collagen in normal skin tissues. The expression of TGF-β RⅠ is higher in peripheral than central areas of hypertrophic scar. Therefore, the peripheral area would be emphasized in the clinic work.