Elevated levels of circulating CD44 in patients with systemic sclerosis: association with a milder subset

Objective. To determine serum levels of soluble CD44 (sCD44), one of the adhesion molecules that regulate the migration of leucocytes, and clinical associations of these levels in patients with systemic sclerosis (SSc). Methods. Serum sCD44 levels were examined by enzyme-linked immunosorbent assay. Results. Serum sCD44 levels were elevated in SSc patients compared with normal controls. Serum sCD44 levels were higher in patients with limited cutaneous SSc than in those with diffuse cutaneous SSc. Patients with elevated sCD44 levels had pulmonary fibrosis less frequently than those with normal sCD44 levels. Serum sCD44 levels remained elevated during the follow-up in almost all patients with elevated levels at their first visit, whereas they remained normal in all patients with normal levels. Conclusion. Elevated sCD44 levels were associated with a relatively mild subset of SSc. These results suggest that CD44 could be a potential therapeutic target in SSc.