Ficolin-3 in chronic Chagas disease: low serum levels associated with the risk of cardiac insufficiency.

AIMS To investigate whether FCN3 polymorphisms and circulating ficolin-3 levels were associated with clinical forms of chronic Chagas disease (CD) and to assess their potential use as biomarkers for the disease or its severity. METHODS AND RESULTS FCN3 polymorphisms (g.1637delC (rs532781899) in exon 5; g.3524_3532insTATTTGGCC (rs28362807) in intron 5 and g.4473C>A) (rs4494157) in intron 7) were determined in 178 chronic CD patients (65 asymptomatic, 68 cardiac, 21 digestive and 24 cardiodigestive), and 285 healthy controls by sequence-specific PCR. Ficolin-3 serum levels, measured by ELISA in 80 patients and 80 controls, did not differ between groups. On the other hand, ficolin-3 levels were positively correlated with left ventricular ejection fraction (p=0.002 r=0.5), with lower levels associated with increased risk of cardiac insufficiency (p=0.033; OR 7.21, 95%IC 1.17-44.4). Ficolin-3 levels were positively correlated with ficolin-2 (p=0.021 r=0.63); and negatively with MBL (p=0.002 r=-0.36) and pentraxin-3 (p=0.04 r=-0.32) levels. No significant results were observed for the investigated FCN3 polymorphisms and CD. The g.1637del/1637C heterozygotes presented lower ficolin-3 levels than g.1637C/1637C homozygotes in the control group (p=0.023). CONCLUSION Low ficolin-3 levels may play a role in the pathophysiology of cardiac insufficiency associated with CD.