Recently, we revealed that upon intra-articular knee joint injection of mice, Lpp-carrying EVs displayed pathogenic capacities by giving rise to more severe macroscopic arthritis as well as synovitis in two different mouse strains (NMRI and C57BL/6 wild-type mice), and that such effect was mediated by monocytes/macrophages via TLR2 (Kopparapu et al., 2021). Here, LPP is linked to arthritic joint disease.