Circulating mannan-binding lectin, M-, L-, H-ficolin and collectin-liver-1 levels in patients with acute liver failure

Background & AimsThe complement system is activated in liver diseases including acute liver failure (ALF); however, the role of the lectin pathway of complement has scarcely been investigated in ALF. The pathway is initiated by soluble pattern recognition molecules: mannan-binding lectin (MBL), M-, L-, and H-ficolin and collectin-liver-1 (CL-L1), which are predominantly synthesized in the liver. We aimed to study lectin levels in ALF patients and associations with clinical outcome. MethodsSerum samples from 75 patients enrolled by the US ALF Study Group were collected on days 1 and 3. We included 75 healthy blood donors and 20 cirrhosis patients as controls. Analyses were performed using sandwich-type immunoassays (ELISA, TRIFMA). ResultsAt day 1, the MBL level in ALF patients was 40% lower compared with healthy controls {[median (interquartile range) 0.72g/ml(0.91) vs. 1.15 (1.92)(P=0.02]}, and increased significantly by day 3 [0.83g/ml(0.94)(P=0.01)]. The M-ficolin level was 60% lower [0.54g/ml(0.50) vs. 1.48(1.01)(P<0.0001)]. The CL-L1 level at day 1 was slightly higher compared with healthy controls [3.20g/ml(2.37) vs. 2.64(0.72)(P=0.11)]; this was significant at day 3 [3.35(1.84)(P=0.006)]. H- and L-ficolin levels were similar to healthy controls. Spontaneous ALF survivors had higher levels of MBL at day 1 [0.96g/ml(1.15) vs. 0.60(0.60)(P=0.02)] and lower levels of L-ficolin by day 3 compared with patients who died or were transplanted [1.61g/ml(1.19) vs. 2.17(2.19)(P=0.02)]. ConclusionWe observed significant dynamics in lectin levels in ALF patients, which may suggest they play a role in ALF pathogenesis. High MBL and low L-ficolin levels are associated with survival.