Liver transcriptome analysis reveals PSC-attributed gene set associated with fibrosis progression.

Area of Science:

• Hepatology
• Genomics
• Immunology

Background:

• Primary sclerosing cholangitis (PSC) is a chronic liver disease causing bile duct inflammation, fibrosis, and cirrhosis.
• The exact cause of PSC remains unknown, highlighting the need for research into its mechanisms.
• Identifying specific genetic factors in PSC is crucial for understanding disease progression.

Purpose of the Study:

• To identify a gene signature specific to primary sclerosing cholangitis (PSC) that is associated with the development of biliary fibrosis.
• To differentiate PSC-associated genes from those in other liver diseases like primary biliary cholangitis (PBC) and metabolic dysfunction-associated steatotic liver disease (MASLD).

Main Methods:

• RNA-sequencing was performed on liver biopsies from patients with PSC, PBC, and MASLD at various fibrosis stages.
• Differential gene expression analysis was used to identify genes associated with fibrosis in PSC.
• External transcriptome data was utilized for validation of the identified gene signature.

Main Results:

• A total of 431 genes were associated with fibrosis development in PSC, with 367 being PSC-specific compared to PBC or MASLD.
• Validation reduced this to a set of 150 differentially expressed genes.
• Analysis revealed genetic drivers in cholangiocytes, fibroblasts, and immune cells, with early involvement of macrophage and neutrophil genes in PSC fibrosis.

Conclusions:

• A distinct gene signature associated with biliary fibrosis in PSC has been identified.
• This signature may aid in discovering novel biomarkers and therapeutic targets for PSC fibrogenesis.
• The findings provide a foundation for further research into PSC-specific fibrosis mechanisms.