Dendritic Cell-Depleted Mice Develop the Autoimmune Biliary Disease That Serologically and Pathogenically Models...

Area of Science:

• Immunology
• Hepatology
• Autoimmune Diseases

Background:

• Primary biliary cholangitis (PBC) is an autoimmune liver disease characterized by progressive bile duct damage.
• Dendritic cells (DCs) are critical for immune regulation, and their dysfunction is implicated in autoimmune conditions.

Purpose of the Study:

• To investigate the role of dendritic cell (DC) dysfunction in the development of primary biliary cholangitis (PBC).
• To establish a mouse model of DC-depleted autoimmune biliary disease resembling human PBC and elucidate its underlying mechanisms.

Main Methods:

• Generated DC-depleted mice (ID mice) by crossbreeding CD11c-Cre and Rosa26-DTA mice.
• Assessed hepatobiliary changes via histology, serum biochemistry, flow cytometry, and gene expression analysis (qPCR, RNA-seq).
• Investigated disease induction by injecting wild-type mice with serum from control or ID mice, with and without antibody depletion.

Main Results:

• DC-depleted mice exhibited portal inflammation, elevated antimitochondrial antibody (AMA) levels, and increased expression of inflammatory cytokines.
• Intraperitoneal injection of ID mouse serum induced cholangitis in wild-type mice, characterized by CD4+ T-cell infiltration.
• Depletion of anti-PDCE-2 antibodies from ID serum attenuated the induced cholangitis.

Conclusions:

• Dendritic cell (DC) depletion induces serological and histological features of PBC, suggesting DC dysfunction contributes to immune dysregulation.
• The study implicates CD4+ T-cell activation and anti-PDCE-2 autoantibody production in PBC pathogenesis.
• Both T-cell responses and autoantibodies are essential contributors to the development of primary biliary cholangitis.