Unveiling causal pathways in autoimmune diseases: a multi-omics approach

Area of Science:

• Immunology and Genetics
• Multi-omics Research
• Autoimmune Disease Pathogenesis

Background:

• Autoimmune diseases (ADs) involve complex immune dysregulation.
• Understanding the interplay of genetic, immune, and microbial factors in ADs is crucial.
• Existing research often lacks comprehensive multi-omics integration for causal inference.

Purpose of the Study:

• To investigate causal relationships between circulating proteins, cytokines, gut microbiota, and immune cells in relation to ADs using Mendelian randomization (MR).
• To identify key proteins and pathways involved in AD pathogenesis through integrated bioinformatics analyses.
• To explore potential novel therapeutic targets for ADs.

Main Methods:

• Mendelian randomization (MR) analysis on genome-wide association study (GWAS) data.
• Integration of mediation analysis, protein-protein interaction (PPI) networks, Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses.
• Subnetwork discovery (MCODE), colocalization analysis, and molecular docking for drug target identification.

Main Results:

• Significant causal associations were identified between various omics traits and ADs, with some persisting after FDR correction.
• Inflammatory proteins were found to mediate links between immune cells and psoriasis, and gut microbiota and Hashimoto's thyroiditis.
• 22 key proteins and 15 central proteins were highlighted, with Fms-related tyrosine kinase 3 ligand (FLT3LG) showing strong colocalization evidence; several proteins validated as drug targets.

Conclusions:

• This multi-omics study provides novel insights into the causal pathways underlying autoimmune diseases.
• Identified key proteins and validated drug targets offer promising avenues for developing innovative therapeutic strategies for ADs.
• The findings advance the understanding of AD etiology and pave the way for precision medicine approaches.