title: Dupuytren's disease: The effect of steroids on pro-inflammatory cytokine production and cellular apoptosis
Creators: name: Meek, Robert Marshall Dominic
Publisher: name: University of Glasgow
Year: 2000
Subjects: subject: Immunology, pharmacology, Dupuytren's contracture, apoptosis, steroids.

description: Dupuytren's disease is the result of a chronic inflammatory process, producing progressive contracture of patients' fingers. The histology of Dupuytren's tissue has been well studied; demonstrating inflammatory cells in addition to the myofibroblasts within the Dupuytren's nodule itself These inflammatory cells produce growth factors and cytokines that regulate the proliferation and progressive contracture of the Dupuytren's myofibroblasts. The mechanism of the migration of these inflammatory cells through the endothelial walls of the blood vessels within the Dupuytren's tissue is not well established. This work examined one possible pathway of inflammatory cell adherence to the endothelial cells and their migration. The cells in Dupuytren's tissue expressing the integrin alpha4beta1 and the corresponding ligands, Vascular Cell Adhesion Molecule-1 (VCAM-1) and HepII/IIICS region of fibronectin known as CS1 were studied. Transforming Growth Factor-beta (TGF-beta) is an important group of factors linked with fibrosis. The distribution of TGF-beta production in relationship to the expression of CS1 region of fibronectin was also studied in Dupuytren's tissue. Cells expressing alpha4beta1 were noted principally in and around the blood vessels expressing VCAM-1 and CS1 fibronectin. VCAM-1 was present within the endothelium of blood vessels surrounding and penetrating areas of active nodule growth. TGF-beta was noted to be expressed in very similar areas to the CS1 sequence of fibronectin. Having established this, the effect of methylprednisilone steroid injected locally around the Dupuytren's nodule was studied. The effect of steroids on the expression of growth factors and pro-inflammatory cytokines (Interleukin-1 (IL-1), Interleukin-4 (IL-4), Interleukin-6 (IL-6), Interleukin-8 (IL-8), Tumour Necrosis Factor-alpha (TNF-alpha) and TGF-beta was investigated. In addition, the effect of steroids on the presence of the adhesion molecule VCAM-1, CS1 sequence of fibronectin and alpha4beta1 expressing cells was studied. In Dupuytren's tissue treated with steroid, the studied growth factor and cytokine expression was reduced, VCAM-1 expression was down regulated in the blood vessels, as was CS1 fibronectin and the number of alpha4beta1 expressing cells was reduced. As chronic inflammation may represent a failure of inflammatory cells to undergo apoptosis, the rates of apoptosis and proliferation of cells within the Dupytren's nodule was assessed by immunological staining for the Lewis Y marker and the Ki67 antigen respectively. In addition, cells from Dupuytren's nodules were cultured and studied using flow cytometry measurements of cellular markers of apoptosis (Annexin V binding). This was compared to fibroblast cultures from specimens of pahnar fascia taken at carpal tunnel decompression, where Dupuytren's disease was not present. Fibroblasts were also cultured from specimens of fascia lata taken at hip surgery. These fibroblasts acted as controls. The effect of addition of steroid was again studied. Steroid produced a marked increase in cellular apoptosis, as represented by Lewis Y marker binding and a reduction in proliferation, as measured by Ki67 antigen binding. In the cell culture experunents, Dupuytren's cells were much more sensitive to steroid induced apoptosis than fibroblasts from normal carpal tunnels. By understanding the factors involved in controlling inflammatory cell adherence and transendothelial migration and the subsequent failure to undergo normal apoptosis, therapeutic intervention to prevent progression may be possible.