Levels of cytokines and their receptors (receptor antagonist IL-1β, IL-6, IL-1, TNF-α, IFN-γ, eotaxin, GM-CSF, M-CSF), chemokines (monocyte chemoattractant protein 1 (MCP1), and macrophage inflammatory protein 1α (MIP-1α)) were elevated in the blood of RA patients even before the development of the disease in contrast to healthy individuals and were the highest in ACPA and rheumatoid factor (RF)-positive patients [48]. Here, PRTN3 is linked to rheumatoid arthritis.