Clinical Significance of the Mac-2 Binding Protein Glycosylated Isomer as a Surrogate Marker of Graft Fibrosis After Pediatric Liver Transplantation

Abstract

After pediatric liver transplantation, liver fibrosis may occur during long-term follow-up. Noninvasive markers for assessing this liver fibrosis are desired. Mac-2 binding protein glycosylated isomer (M2BPGi) has recently been reported as a useful biomarker for liver fibrosis. However, its usefulness in the pediatric population is yet to be established. This study investigated the clinical significance of M2BPGi levels as a surrogate marker of graft fibrosis after pediatric liver transplantation. We retrospectively identified 96 patients who underwent pediatric liver transplantation at our institution between 1991 and 2015. The association between M2BPGi levels and other fibrosis markers was analyzed in 60 patients in whom fibrosis markers were measured. The association between fibrosis marker levels and graft fibrosis was assessed in 42 patients who underwent biopsies between 2016 and 2022. The M2BPGi levels were statistically correlated with the hyaluronic acid and type-IV collagen levels. None of the fibrosis markers were significantly associated with liver graft fibrosis, although the levels of these markers were slightly higher in patients with severe liver fibrosis than in those with mild fibrosis. The M2BPGi levels had a limited ability to assess liver graft fibrosis after pediatric liver transplantation, similar to other fibrosis markers. Further studies with larger cohorts are required to validate these findings externally.