Plasma proteins and rheumatoid arthritis: A Mendelian randomization analysis

Area of Science:

• Genetics and Genomics
• Immunology
• Proteomics

Background:

• Rheumatoid arthritis (RA) is a chronic, systemic autoimmune disease with significant global health impact and unclear origins.
• Identifying reliable biomarkers and therapeutic targets is crucial for improving RA diagnosis and treatment.

Purpose of the Study:

• To identify plasma proteins associated with rheumatoid arthritis (RA) risk using large-scale Mendelian randomization (MR) and proteomics.
• To discover potential biomarkers for early RA diagnosis and novel therapeutic targets for personalized treatment strategies.

Main Methods:

• A large-scale plasma proteome Mendelian randomization (MR) study was conducted using genetic data from European individuals (58,293 participants: 14,361 RA patients, 43,932 controls).
• Plasma protein quantitative trait loci data from 35,559 Icelanders were analyzed using various MR methods (MR-Egger, inverse-variance weighting, etc.).
• Statistical analyses included heterogeneity and pleiotropy assessments, leave-one-out sensitivity analyses, Gene Ontology, KEGG pathway, and protein-protein interaction analyses.

Main Results:

• MR analysis identified associations between 4907 plasma proteins and RA risk.
• Eleven novel plasma proteins showed significant associations with RA risk (False Discovery Rate < 0.20).
• Specific proteins like C2 were associated with increased RA risk, while USP25 and ATF6 were linked to decreased risk. Pathway analyses indicated involvement in immune cell migration and signaling.

Conclusions:

• This study successfully identified novel plasma proteins and biological pathways causally linked to rheumatoid arthritis.
• The findings provide potential new biomarkers for RA diagnosis and therapeutic targets for future clinical applications.
• Further functional and clinical research is warranted to elucidate the biological roles and translational potential of these identified proteins and pathways.