Background and Aims: The impact of antibody response after direct-acting antiviral (DAA) therapy in hepatitis C virus (HCV)-infected recipients before and after liver transplantation (LT) is still undetermined. Methods: In this observational cohort study, we aimed to explore the association of changes in anti-HCV antibody titers after pre-LT DAA therapy with allograft injury, including biliary complications (BCs) and acute cellular rejection (ACR). Results: A total of 153 cases were enrolled from January 2015 to February 2021. Serum anti-HCV antibody titers were assessed before and after (day 30) LT. Among all recipients, 31/153 (20.3%) had pre-LT DAA therapy (DAA group) and 122/153 (79.7%) did not undergo pre-LT DAA therapy (DAA-naïve group). Higher incidence of post-LT BCs was observed in the DAA group (P = 0.028). Compared with the DAA-naïve group, the DAA group had a significantly higher mean level of anti-HCV titer upregulation (P = 0.0024); furthermore, among the recipients with BCs (n = 28) and ACR (n = 41), those in the DAA group exhibited significantly higher mean levels of anti-HCV antibody titer upregulation (P < 0.005). Conclusion: In conclusion, we speculated that anti-HCV antibody titer upregulation, which might have been induced by restoration of HCV-specific immune responses with pre-LT DAA therapy, were associated with post-LT allograft injury.

Background: miRNA-122 has been reported to be a useful tool for monitoring ACR after LT. IL-28B SNP rs8099917 genotype is known to contribute to the control of HCV infection. We sought to investigate the relationship between IL-28B SNP rs8099917 genotype and miRNA-122 expression and immune mechanism of ACR after LT using hepatitis C antibody calibration. Patients and Methods: A total of 45 patients with chronic hepatitis C received LDLT. IL-28B SNP rs8099917 genotyping was used to divide TT and GT groups. The relative expression levels of miRNA-122 were calculated by quantitative PCR as 2[(Ct of miR-122) (Ct of U6)] normalized to a reference gene and compared to a control sample, and the anti-HCV titers before and after LT were tracked to observe the relationship with ACR. Results: In the genotype of rs8099917, TT was significantly more associated with higher serum miRNA-122 levels than GT (p = 0.029). The ACR was significantly higher in genotype TT than in GT (p = 0.002). TT was significantly associated with low levels of pre-LT anti-HCV compared with GT (p = 0.022). Multivariate analysis with 95% confidence intervals showed a significant association between rs8099917 genotype TT, lower pre-LT and higher post-LT anti-HCV and ACR. Conclusion: Based on our current data, IL-28B SNP rs8099917 genotype TT may express higher miRNA-122 and correlate with lower Pre-LT and higher Post-LT anti-HCV titers, and may correlate to the pathogenesis of ACR after LT.