BDNF and systemic sclerosis: Serum NGF levels were higher in SSc patients (288.26±170.34 pg/mL) than in healthy controls (170.34±50.8 pg/mL, p<0.0001) (Figure 1A) whereas BDNF levels were lower (1121.9±158.1 vs 1372.9±190.9 pg/mL) (Figure 1B).