Elevated transcription of heat shock protein gene in scleroderma fibroblasts

Scleroderma is a systemic disorder characterized by fibrosis, which affects skin, lung, kidney and other organs. Heat shock protein (hsp) (70 kD) has been implicated as an essential element of cell function in cell growth and differentiation. To study the molecular basis of intracellular events in scleroderma fibroblasts, we compared the expression of hsp 70 gene in scleroderma and normal control fibroblasts by nuclear run on transcription assay and Northern blot assay. We show that scleroderma fibroblasts express more than eight times higher level of hsp 70 transcription in normal control fibroblasts at quiescent conditions in the absence of serum. After stimulation with serum, the transcription level of the hsp 70 gene is similar in scleroderma and normal control fibroblasts. Therefore, our results indicate an alteration/activation of intracellular events in scleroderma fibroblasts.