Serum levels of galectin-3: possible association with fibrosis, aberrant angiogenesis, and immune activation in patients with systemic sclerosis.

OBJECTIVE: Galectin-3 is a multifunctional protein implicated in a variety of biological processes including fibrosis, angiogenesis, and immune activation, all of which are associated with the development of systemic sclerosis (SSc). We investigated the clinical significance of serum galectin-3 levels in SSc.
METHODS: Serum galectin-3 levels were determined by a specific ELISA in 58 patients with SSc and 19 healthy controls.
RESULTS: Serum galectin-3 levels were significantly lower in patients with diffuse cutaneous SSc (dcSSc) than in controls (3.29 ± 3.27 ng/ml vs 4.91 ± 2.67 ng/ml, respectively; p < 0.05), while being comparable between limited cutaneous SSc (3.70 ± 2.39 ng/ml) and healthy controls. In dcSSc, serum galectin-3 levels significantly correlated with total skin score (r = 0.45, p < 0.05). Serum galectin-3 levels were significantly decreased in early dcSSc (disease duration < 1 year; 1.64 ± 1.74 ng/ml; p < 0.05), but not in mid-stage dcSSc (1 to 6 years; 3.22 ± 3.16 ng/ml) or late-stage dcSSc (> 6 years; 4.86 ± 4.10 ng/ml), compared with controls. Serum galectin-3 levels were higher in SSc patients with both digital ulcers (DU) and elevated right ventricular systolic pressure (RVSP) than in those without each symptom (DU: 5.44 ± 3.74 ng/ml vs 2.99 ± 2.36 ng/ml, p < 0.05; elevated RVSP: 4.44 ± 3.14 ng/ml vs 2.82 ± 2.64 ng/ml, p < 0.05).
CONCLUSION: Galectin-3 may be related to the developmental process of skin sclerosis in dcSSc and of DU and pulmonary vascular involvements in total SSc.