Background: The etiopathogenesis of systemic sclerosis (SSc)--an autoimmunological disease characterized by excess collagen and other connective tissue components in skin and internal organs--remains unclear. Given the potential role of matrix enzymes, metalloproteinases, and their tissue inhibitors in pulmonary fibrosis, we assayed the serum concentration of tissue inhibitor of metalloproteinases 2 (TIMP-2) in patients with SSc and explored its possible correlation with the duration of Raynaud's phenomenon, the intensity of sclerosis of the skin, and pulmonary lesions.
Material/methods: We studied 18 SSc patients, 8 with limited SSc and ten with diffuse. The degree of sclerosis of the skin was measured using the Total Skin Scale. Chest x-rays and spirometric examinations were also performed. The presence and type of antinuclear antibodies (ANA) were determined by indirect immunofluorescence and double immunodiffusion in agar gelatin. Serum TIMP-2 concentration was measured by ELISA.
Results: The average serum TIMP-2 concentration was not significantly higher in SSc patients than in controls. No statistically significant difference was found in this respect between limited and diffuse SSc. Despite the lack of correlation between the duration of Raynaud's phenomenon, the degree of sclerosis of the skin, and the serum concentration of TIMP-2, the latter concentration was higher in patients with restrictive pulmonary dysfunction in spirometric testing.
Conclusions: Our research, though involving a small group of patients, points to the probable role of TIMP-2 in the development of pulmonary fibrosis.