The Different Characteristics of Dupuytren’s Disease Fibroblasts Derived from Either Nodule or Cord: Expression of α-Smooth Muscle Actin and the Response to Stimulation by TGF-β1

Abstract

Mechanisms behind the onset and progression of Dupuytren’s disease are poorly understood. Both myofibroblasts and transforming growth factor beta 1 (TGF-β1) have been implicated. We studied fibroblast cultures derived from nodules or cords of Dupuytren’s contracture tissue to determine the proportion of myofibroblasts present in comparison with flexor retinaculum fibroblast cultures. We identified myofibroblasts by immunohistochemical staining for α-SMA. We then investigated the effects of TGF-β1stimulation on these fibroblasts.Basal myofibroblast/fibroblast proportions were 9.7% in nodule cell cultures, 2.7% in cord cell cultures and only 1.3% in flexor retinaculum cell cultures. Nodule and cord myofibroblast proportions increased to 25.4% and 24.2%, respectively, in response to TGF-β1treatment. Flexor retinaculum cell cultures showed no response to TGF-β1stimulation.Fibroblasts cultured from specific regions of Dupuytren’s tissue retain myofibroblast features in culture. TGF-β1stimulation causes an increased myofibroblast phenotype to similar levels in both nodule and cord, suggesting that previously quiescent cord fibroblasts can be reactivated to become myofibroblasts by TGF-β1. This could be an underlying reason for high recurrence rates seen after surgery or progression following injury.