Proteomic profiling of serum samples from an established RA cohort (72 female and 19 male that were at least 84% ACPA+) was performed using an aptamer-based SomaScan platform.<h4>Results</h4>We identified distinct sex-related differences in disease severity and pro-inflammatory profiles in the sera and joint tissues of CIA mice, with inflammatory responses that were male-skewed in the sera and female-skewed in the joints. This evidence concerns the gene PRTN3 and rheumatoid arthritis.