A novel serum marker, glycosylated Wisteria floribunda agglutinin-positive Mac-2 binding protein (WFA⁺-M2BP), for assessing liver fibrosis

Background: Recently, a novel marker, hyperglycosylated Wisteria floribunda agglutinin-positive Mac-2 binding protein (WFA⁺-M2BP), was developed for liver fibrosis using the glycan “sugar chain”-based immunoassay; however, the feasibility of WFA⁺-M2BP for assessing liver fibrosis has not been proven with clinical samples of hepatitis.

Methods: Serum WFA⁺-M2BP values were evaluated in 200 patients with chronic liver disease who underwent histological examination of liver fibrosis. The diagnostic accuracy of WFA⁺-M2BP values was compared with various fibrosis markers, such as ultrasound based-virtual touch tissue quantification (VTTQ), magnetic resonance imaging based-liver-to-major psoas muscle intensity ratio (LMR), and serum markers, including hyaluronic acid, type 4 collagen, and aspartate transaminase to platelet ratio index (APRI).

Results: Serum WFA⁺-M2BP levels in patients with fibrosis grades F0, F1, F2, F3, and F4 had cutoff indices 1.62, 1.82, 3.02, 3.32, and 3.67, respectively, and there were significant differences between fibrosis stages F1 and F2, and between F2 and F3 (P < 0.01). The area under the receiver operating characteristic curves for the diagnosis of fibrosis (F ≥ 3) using serum WFA⁺-M2BP values (0.812) was almost comparable to that using VTTQ examination (0.814), but was superior to the other surrogate markers, including LMR index (0.766), APRI (0.694), hyaluronic acid (0.683), and type 4 collagen (0.625) (P < 0.01 each).

Conclusions: Serum WFA⁺-M2BP values based on a glycan-based immunoassay is an accurate, reliable, and reproducible method for the assessment of liver fibrosis. This approach could be clinically feasible for evaluation of beneficial therapy through the quantification of liver fibrosis in hepatitis patients if this measurement application is commercially realized.