PsA patients showed similar IHC CD68+ cell score in the lining (1.95 ± 0.90) and sublining (1.81 ± 0.95) compared to Abneg RA patients (1.96 ± 0.75 for lining CD68+ cells, p = 0.94; 1.43 ± 0.76 for sublining CD68+ cells, p = 0.11 respectively) regardless of the treatment scheme (Fig. 1a–d). This evidence concerns the gene CD68 and rheumatoid arthritis.