UVA1-induced decrease in dermal neuron-specific enolase (NSE) in acrosclerosis

Besides its role in small-cell carcinoma of the lung, elevated serum levels of neuron-specific enolase (NSE) have recently been reported to be associated with autoimmune rheumatic disorders such as systemic sclerosis. Serum NSE seems to correlate with disease activity as well as Rodnan skin score. The aim of the study was to assess the neuromodulatory effects of conventional UVA1 phototherapy on acrosclerosis as an additional mechanism besides an assumed T cell apoptosis, collagenase induction and angiogenesis. Punch skin biopsies of acrosclerotic skin lesions taken before and after treatment from four patients were evaluated immunohistochemically for the presence of NSE, S100 and neurofilament. Immunolabeling revealed a UVA-induced decrease in dermal NSE expression. In contrast, no alteration in neurofilament+ cells could be detected. In line with the findings of a previous investigation, a high number of S100+ cells were detected in most specimens. We demonstrated a UVA1-induced reduction in dermal NSE levels correlating with a softening of former sclerotic lesions. Even though the origin and the functional mechanisms remain obscure, NSE might be relevant directly within sclerotic skin lesions and may possibly be used as a diagnostic marker at least in SSc-associated acrosclerotic skin.