DNA Methylation-mediated BTN3A2 Regulation via CD14+CD16+ Monocytes Protects Against Primary Sclerosing Cholangitis

Area of Science:

• Genetics
• Immunology
• Hepatology

Background:

• Primary Sclerosing Cholangitis (PSC) presents diagnostic and therapeutic challenges due to its unclear origins.
• Novel pathogenic pathways for PSC require investigation.

Purpose of the Study:

• To explore novel genetic and immune-related mechanisms in PSC pathogenesis using Mendelian Randomization (MR).
• To identify potential causal factors and therapeutic targets for PSC.

Main Methods:

• Analysis of diverse omics datasets including eQTL, pQTL, immune cell profiles, DNA methylation, and PSC GWAS data.
• Application of Inverse Variance Weighted (IVW) method for causal gene identification.
• Mediation analyses to understand the roles of DNA methylation and immune cells in PSC.

Main Results:

• BTN3A2 gene expression demonstrated a significant protective association with PSC risk (OR 0.838, P=1.12E-09).
• DNA methylation at cg23465465 significantly mediated PSC risk via BTN3A2 regulation (89.3% mediation).
• BTN3A2 provided partial protection through CD14+CD16+ monocytes (4.7% mediation).

Conclusions:

• BTN3A2 acts as a causal protective factor in PSC, influenced by DNA methylation.
• Immune mechanisms involving CD14+CD16+ monocytes contribute to PSC pathogenesis.
• Findings suggest BTN3A2 as a potential therapeutic target for PSC precision medicine, pending experimental validation.