Anti-integrin αvβ6 Autoantibodies in the Recurrence of Primary Sclerosing Cholangitis Following Liver Transplantation

Background Prediction and diagnosis of recurrent primary sclerosing cholangitis (rPSC) after liver transplantation remain challenging. We investigated anti-integrin v{beta}6 autoantibody titers and their association with rPSC development. Methods Twenty-three patients with PSC with serial serum samples and liver biopsies after liver transplantation were included. rPSC was diagnosed according to the 2024 Japanese diagnostic criteria. Anti-integrin v{beta}6 autoantibody titers were measured by enzyme-linked immunosorbent assays. Fold changes (FCs) in antibody titers were calculated relative to each patient's pre-transplant baseline, and the maximum FC during post-transplant follow-up was defined as FCmax. Results Antibody titers significantly decreased at the first postoperative measurement compared with the pre-transplant level. Ten of 23 patients developed rPSC. Three patients whose ulcerative colitis activity changed after transplantation were excluded from further analysis, leaving 20 patients. The maximum absolute antibody titer during post-transplant follow-up was not associated with rPSC development. However, FCmax was significantly higher in patients with rPSC than in those without rPSC (1.381 vs. 0.514, P = 0.041), with an AUC of 0.781. Conclusions Anti-integrin v{beta}6 autoantibody titers significantly decreased after liver transplantation for PSC. Post-transplant antibody re-elevation relative to the pre-transplant baseline was significantly associated with the development of rPSC.