Stimulation with TNF-α showed no effects on the NLRP1, whereas significantly upregulated the expression of NLRP3. When comparing different forms of arthritis, significantly lower expression of NLRP3 under stimulation with TNF-α was observed in the RA group compared with all other tested groups, suggesting potential contribution of altered NLRP3 activation to the etiopathogenesis of advanced RA. Here, NLRP1 is linked to rheumatoid arthritis.