biostudies-literatureUnknown13Schultz MSeptic arthritis, most often caused by <i>Staphylococcus aureus</i>, is a rapidly progressive and destructive joint disease with substantial mortality and morbidity. <i>Staphylococcus aureus</i> lipoproteins (Lpps) are known to induce arthritis and bone destruction. Here, we aimed to investigate the bone resorptive effect of <i>S. aureus</i> Lpps in a murine arthritis model by intra-articular injection of purified <i>S. aureus</i> Lpps, synthetic lipopeptides, and live <i>S. aureus</i> strains. Analyses of the bone mineral density (BMD) of the distal femur bone were performed. Intra-articular injection of both live <i>S. aureus</i> and purified <i>S. aureus</i> Lpps were shown to significantly decrease total- and trabecular BMD. Liquid chromatography-mass spectrometry analyses revealed that the Lpps expressed by <i>S. aureus</i> SA113 strain contain both diacyl and triacyl lipid moieties. Interestingly, synthetic diacylated lipopeptide, Pam₂CSK₄, was more potent in inducing bone resorption than synthetic triacylated lipopeptide, Pam₃CSK₄. Modified lipoproteins lacking the lipid moiety were deprived of their bone resorptive abilities. Monocyte depletion by clodronate liposomes fully abrogated the bone resorptive capacity of <i>S. aureus</i> lipoproteins. Our data suggest that <i>S. aureus</i> Lpps induce bone resorption in locally-induced murine arthritis, an effect mediated by their lipid-moiety through monocytes/macrophages.Frontiers in microbiology843799https://www.ebi.ac.uk/biostudies/studies/S-EPMC8959583biostudies-literatureLipoproteins Cause Bone Resorption in a Mouse Model of <i>Staphylococcus aureus</i> Septic Arthritis.PMC8959583Jarneborn AWienken CMFroning MHu ZJin TSchultz MNguyen MTAli APullerits RMohammad MHayen HGotz FfalseLipoproteins Cause Bone Resorption in a Mouse Model of <i>Staphylococcus aureus</i> Septic Arthritis.Septic arthritis, most often caused by <i>Staphylococcus aureus</i>, is a rapidly progressive and destructive joint disease with substantial mortality and morbidity. <i>Staphylococcus aureus</i> lipoproteins (Lpps) are known to induce arthritis and bone destruction. Here, we aimed to investigate the bone resorptive effect of <i>S. aureus</i> Lpps in a murine arthritis model by intra-articular injection of purified <i>S. aureus</i> Lpps, synthetic lipopeptides, and live <i>S. aureus</i> strains. Analyses of the bone mineral density (BMD) of the distal femur bone were performed. Intra-articular injection of both live <i>S. aureus</i> and purified <i>S. aureus</i> Lpps were shown to significantly decrease total- and trabecular BMD. Liquid chromatography-mass spectrometry analyses revealed that the Lpps expressed by <i>S. aureus</i> SA113 strain contain both diacyl and triacyl lipid moieties. Interestingly, synthetic diacylated lipopeptide, Pam₂CSK₄, was more potent in inducing bone resorption than synthetic triacylated lipopeptide, Pam₃CSK₄. Modified lipoproteins lacking the lipid moiety were deprived of their bone resorptive abilities. Monocyte depletion by clodronate liposomes fully abrogated the bone resorptive capacity of <i>S. aureus</i> lipoproteins. Our data suggest that <i>S. aureus</i> Lpps induce bone resorption in locally-induced murine arthritis, an effect mediated by their lipid-moiety through monocytes/macrophages.2022-01-01T00:00:00Z20222025-04-19T20:10:26.523Z2025-04-19T20:10:26.523ZS-EPMC89595833535651810.3389/fmicb.2022.843799