Cyclic mechanical stretching modulates secretion pattern of growth factorsin human tendon fibroblasts

The objective of the study was to investigate whether the response profile of the growth factor of human tendon fibroblasts could be beneficially infl uenced through the application of mechanical stretch. It was considered tha t this would elucidate structural and functional problems, often seen after tendon and ligament healing. The secretion pattern of transforming growth factor-beta (TGF-beta), platelet-derived growth factor (PDGF) and basic fib roblast growth factor (bFGF) was determined in mechanically stretched fibro blasts and compared to non-stretched controls. Human tendon fibroblasts wer e experimentally stretched for 15 and 60 min at a frequency of I Hz and an amplitude of 5%. The secretion of TGF-beta, PDGF and bFGF was measured by e nzyme-linked immuno-sorbent assay. All the growth factors investigated were indeed secreted by human tendon fibroblasts both in stretched cells and co ntrols. Mechanical stretch increased the secretion pattern of the growth fa ctors. The increased concentrations of TGF-beta, bFGF and PDGF after cyclic al mechanical stretching may have a positive influence on tendon and ligame nt healing through stimulation of cell proliferation, differentiation and m atrix formation.