IL6 and rheumatoid arthritis: After the LPS-and-IFN-γ stimulus, the PERIO group also presented a higher expression of IL-6 (MFI) by monocytes (median of 4634.00) compared to the other two groups, which was statistically significant between the PERIO and the PERIO+RA (median of 1316.00) (p = 0.008) (Table 2).