Objective:

To identify immune-cell-specific genetic regulatory signals associated with rheumatoid arthritis (RA) and assess candidate genes and pathways using integrated transcriptomic, computational, and experimental evidence.

Approach:

• Genetic analysis: Cell-type-specific cis-eQTLs from 17 immune-cell populations were integrated with RA GWAS summary statistics using two-sample Mendelian randomization. Single-instrument exposures used the Wald ratio; multiple-instrument exposures used inverse-variance weightin…
• Integrated prioritization: The study combined transcriptomic, WGCNA, machine-learning, single-cell expression, and virtual gene-perturbation analyses to prioritize targets and examine cellular specificity and potential regulatory relationships.
• Validation and translational assessment: Drug-screening analyses and in vitro experiments were used to assess candidate-pathway relevance.

Key Findings:

• The article context identifies a monocyte-linked PRKCB–CTSL pathway as a potential regulatory mechanism and therapeutic target in RA.
• The provided context describes the analysis framework but does not report specific effect estimates, statistical results, or experimental validation outcomes.

Interpretation:

The study uses cell-type-specific genetic instruments alongside independent molecular and experimental approaches to investigate whether genetically regulated expression is associated with RA susceptibility and to evaluate candidate pathways.

Limitations:

• The supplied context does not include detailed results, effect sizes, confidence intervals, or significance values.
• The supplied context does not describe the outcomes or scope of the in vitro validation or drug-screening analyses.
• The described MR methods depend on the number of eligible independent cis-eQTL instruments for each cell-type–gene exposure.