Fibronectin gene expression differs in normal and abnormal human wound healing.

Area of Science:

• Biochemistry
• Dermatology
• Wound Healing Research

Background:

• Keloids and hypertrophic scars involve abnormal extracellular matrix regulation, specifically fibronectin and collagen overproduction.
• Understanding extracellular matrix gene expression differences in normal versus abnormal wound healing is crucial.

Purpose of the Study:

• To compare fibronectin messenger RNA and protein biosynthesis in fibroblasts from normal skin, normal scars, keloids, and hypertrophic scars.
• To investigate similarities and differences in fibronectin expression during normal and abnormal wound healing processes.

Main Methods:

• Cultured fibroblasts from normal skin, normal scars, keloids, and hypertrophic scars were analyzed for fibronectin messenger RNA and protein synthesis rates.
• In situ hybridization and immunohistochemistry were used to examine fibronectin messenger RNA and protein content in tissue samples.

Main Results:

• Fibronectin expression was elevated in fibroblasts from both normal and abnormal wounds compared to quiescent normal skin.
• Fibroblasts from keloids showed higher fibronectin expression (messenger RNA and protein synthesis) than matched normal skin fibroblasts.
• In vivo, fibronectin messenger RNA and protein levels were highest in abnormal wounds, followed by normal scars, and lowest in normal skin.

Conclusions:

• Fibroblasts in keloids and hypertrophic scars overexpress fibronectin both in vivo and in vitro.
• The fibronectin regulatory pathway in scar fibroblasts is influenced by the local tissue environment.
• Fibroblast behavior in vitro suggests a potential for environmental modulation of fibronectin expression in scar tissue.