A study of the abnormalities of human epiderm in keloids and hypertrophic scars

Abstract

To investigate the abnormalities of human epiderm in keloids and hypertrophic scars. Biopsies from ten untreated keloids (duration of disease 3 - 30 years) and ten hypertrophic scars (duration of disease 6 - 10 months) and five normal adult skin specimens. Total RNA was isolated from normal adult skin. A cDNA fragment (base 5941 - 6481 bp) of the full-length human Tenascin-C cDNA was synthesized by polymerase chain reaction and subcloned in pGEM-T-easy. Dioxigen-labeled anti-sense and sense probes were synthesized by using a Sp6/T7 in vitro RNA synthesis kit in the present of Dig-UTP. In situ hybridization was performed on 4% paraformaldehyde-fixed and wax-embedded sections of keloids and hypertrophic scars. NBT-NCIP was used in color detection. Immunohistochemical procedure. The sections were incubated with antibodies (anti-Tenascin-C, anti-CK-16 and anti-Ki-67). Ultrasensitive Streptavidin Peroxidase staining was performed following established procedures. The study show that the proliferation of epidermal keratinocytes in keloids and hypertrophic scars is very clear. The expressions of Tenascin-C mRNA in keloids epidermal keratinocytes markedly increased in contrast with epidermal keratinocytes of hypertrophic scars and adult skin. The CK-16 and Ki-67 stainings significantly enhanced in the epidermal keratinocytes of keloids and hypertrophic scars. The different expressions of Tenascin-C, CK-16 and Ki-67 among normal adult skin, keloids and hypertrophic scars show the abnormalities of epidermal keratinocytes proliferation and differentiation in keloids and hypertrophic scars.