TLR9 and rheumatoid arthritis: FLSs internalize NETs containing arthrogenic peptides via the RAGE-TLR9 axis, promoting inflammatory response and cartilage damage (68)MMP plays an important role in cartilage degradation. There is a need to investigate the development of Antibody (Ab)-induced arthritis in MMP-2/MMP-9 mice (75)Elastase derived from NETs was found in the peripheral blood of RA patients to magnify cartilage injury and aggravate RA inflammation (76)