Performance of 2D-shear wave elastography in autoimmune hepatitis-primary biliary cholangitis overlap syndrome.

PURPOSE: To evaluate the diagnostic values of liver stiffness (LS) measured by 2D-SWE, fibrosis index based on the four factors (FIB-4), aspartate aminotransferase to platelet ratio index (APRI), and GGT to PLT ratio (GPR) for assessing liver fibrosis and high-risk esophageal varices (EVs) in patients with autoimmune hepatitis-primary biliary cholangitis (AIH-PBC) overlap syndrome. METHODS: Data of 141 patients were retrospectively collected. Liver fibrosis was staged according to the Scheuer scoring system. The Spearman correlation coefficient was used for correlation analysis. Receiver operating characteristic (ROC) curves were plotted to evaluate the diagnostic performance. RESULTS: LS and FIB-4 were positively correlated with the fibrosis stage (r = 0.555 and 0.198, respectively). LS had significantly higher areas under the ROC curves (AUROCs) values than FIB-4 for predicting advanced fibrosis (0.818 vs. 0.567, P < 0.001), cirrhosis (0.879 vs. 0.637, P < 0.001), whereas LS and FIB-4 similarly predicted significant fibrosis (0.748 vs. 0.638, P = 0.071) and high-risk EVs (0.731 vs. 0.659, P = 0.303). The optimal cut-off values of 2D-SWE for detecting significant fibrosis, advanced fibrosis, cirrhosis, and high-risk EVs were 8.7 kPa, 12.8 kPa, 14.0 kPa, and 11.0 kPa, respectively. LS values were influenced by fibrosis stage, serum GGT, albumin, and total bilirubin levels. The overall concordance rate of the liver stiffness vs. Scheuer stages was 49.65%. CONCLUSIONS: 2D-SWE shows significantly greater diagnostic accuracy than serum fibrosis indexes for diagnosing advanced fibrosis and cirrhosis in patients with AIH-PBC overlap syndrome.

Spontaneous development of an autoimmune hepatitis - primary biliary cholangitis overlap syndrome in dnTGFßRII Aire-/- mice.

Autoimmune regulator (Aire) and TGF-ß signaling play important roles in central tolerance and peripheral tolerance, respectively, by eliminating or suppressing the activity of autoreactive T cells. We previously demonstrated that dnTGFßRII mice develop a defect in peripheral tolerance and a primary biliary cholangitis (PBC)-like disease. We hypothesized that by introducing the Aire gene to this model, we would observe a more severe PBC phenotype. Interestingly, however, we demonstrated that, while dnTGFßRII Aire-/- mice do manifest key histological and serological features of autoimmune cholangitis, they also develop mild to moderate interface hepatitis and show high levels of alanine transaminase (ALT) and antinuclear antibodies (ANA), characteristics of autoimmune hepatitis (AIH). To further understand this unique phenotype, we performed RNA sequencing (RNA-seq) and flow cytometry to explore the functional pathways and immune cell pathways in the liver of dnTGFßRII Aire-/- mice. Our data revealed enrichments of programmed cell death pathways and predominant CD8+ T cell infiltrates. Depleting CD8+ T cells using an anti-CD8α antibody significantly alleviated hepatic inflammation and prolonged the life span of these mice. Finally, RNA-seq data indicated the clonal expansion of hepatic CD8+ T cells. In conclusion, these mice developed an autoreactive CD8+ T-cell-mediated autoimmune cholangitis with concurrent hepatitis that exhibited key histological and serological features of the AIH-PBC overlap syndrome, representing a novel model for the study of tolerance and autoimmune liver disease. © 2023 The Pathological Society of Great Britain and Ireland.