There is a link between high lipopolysaccharide(LPS)levels in the blood and the metabolic syndrome,and metabolic syndrome predisposes patients to severe COVID-19.Here,we define an interaction between SARS-CoV-2 spike(...There is a link between high lipopolysaccharide(LPS)levels in the blood and the metabolic syndrome,and metabolic syndrome predisposes patients to severe COVID-19.Here,we define an interaction between SARS-CoV-2 spike(S)protein and LPS,leading to aggravated inflammation in vitro and in vivo.Native gel electrophoresis demonstrated that SARS-CoV-2 S protein binds to LPS.Microscale thermophoresis yielded a of〜47 nM for the interaction.Computational modeling and all-atom molecular dynamics simulations further substantiated the experimental results,identifying a main LPS-binding site in SARS-CoV-2 S protein.S protein,when combined with low levels of LPS,boosted nuclear factor-kappa B(NF-k B)activation in monocytic THP-1 cells and cytokine responses in human blood and peripheral blood mononuclear cells,respectively.The in vitro inflammatory response was further validated by employing NF-kB reporter mice and in vivo bioimaging.Dynamic light scattering,transmission electron microscopy,and LPS-FITC analyses demonstrated that S protein modulated the aggregation state of LPS,providing a molecular explanation for the observed boosting effect.Taken together,our results provide an interesting molecular link between excessive inflammation during infection with SARS-CoV-2 and comorbidities involving increased levels of bacterial endotoxins.展开更多
Accumulating evidence indicates a potential role for bacterial lipopolysaccharide(LPs)in the overactivation of the immune response during SARS-CoV-2 infection.LPS is recognized by Toll-like receptor 4,mediating proinf...Accumulating evidence indicates a potential role for bacterial lipopolysaccharide(LPs)in the overactivation of the immune response during SARS-CoV-2 infection.LPS is recognized by Toll-like receptor 4,mediating proinflammatory effects.We previously reported that LPS directly interacts with SARS-CoV-2 spike(S)protein and enhances proinflammatory activities.Using native gel electrophoresis and hydrogen-deuterium exchange mass spectrometry,we showed that LPS binds to multiple hydrophobic pockets spanning both the S1 and S2 subunits of the S protein.Molecular simulations validated by a microscale thermophoresis binding assay revealed that LPS binds to the S2 pocket with a lower affinity compared to S1,suggesting a role as an intermediate in LPS transfer.Congruently,nuclear factor-kappa B(NF-kB)activation in monocytic THP-1 cells is strongly boosted by S2.Using NF-kB reporter mice followed by bioimaging,a boosting effect was observed for both S1 and S2,with the former potentially facilitated by proteolysis.The Omicron S variant binds to LPS,but with reduced affinity and LPS boosting in vitro and in vivo.Taken together,the data provide a molecular mechanism by which S protein augments LPS-mediated hyperinflammation.展开更多
基金This work was supported by grants from the Swedish Research Council(Project 2017-02341)the Welander-Finsen,Crafoord,Torsten Soderberg,and Osterlund Foundations,The Royal Physiographic Society of Lund,The Swedish Government Funds for Clinical Research(ALF)Bll(A*STAR)core funds.
文摘There is a link between high lipopolysaccharide(LPS)levels in the blood and the metabolic syndrome,and metabolic syndrome predisposes patients to severe COVID-19.Here,we define an interaction between SARS-CoV-2 spike(S)protein and LPS,leading to aggravated inflammation in vitro and in vivo.Native gel electrophoresis demonstrated that SARS-CoV-2 S protein binds to LPS.Microscale thermophoresis yielded a of〜47 nM for the interaction.Computational modeling and all-atom molecular dynamics simulations further substantiated the experimental results,identifying a main LPS-binding site in SARS-CoV-2 S protein.S protein,when combined with low levels of LPS,boosted nuclear factor-kappa B(NF-k B)activation in monocytic THP-1 cells and cytokine responses in human blood and peripheral blood mononuclear cells,respectively.The in vitro inflammatory response was further validated by employing NF-kB reporter mice and in vivo bioimaging.Dynamic light scattering,transmission electron microscopy,and LPS-FITC analyses demonstrated that S protein modulated the aggregation state of LPS,providing a molecular explanation for the observed boosting effect.Taken together,our results provide an interesting molecular link between excessive inflammation during infection with SARS-CoV-2 and comorbidities involving increased levels of bacterial endotoxins.
基金This work was supported by BIl(A*STAR)core fundsgrants FY21_CF_HTPO SEED_ID_BIl_C211418001 funded by A*STAR+3 种基金the Swedish Research Council(projects 2017-02341 and 2020-02016)Edvard Welanders Stiftelse and Finsenstiftelsen(Hudfonden)the Torsten Soderberg,Crafoord,and Osterlund Foundations,Stiftelsen Lars Hiertas Minnethe Royal Physiographic Society of Lund,and the Swedish Government Funds for Clinical Research(ALF).
文摘Accumulating evidence indicates a potential role for bacterial lipopolysaccharide(LPs)in the overactivation of the immune response during SARS-CoV-2 infection.LPS is recognized by Toll-like receptor 4,mediating proinflammatory effects.We previously reported that LPS directly interacts with SARS-CoV-2 spike(S)protein and enhances proinflammatory activities.Using native gel electrophoresis and hydrogen-deuterium exchange mass spectrometry,we showed that LPS binds to multiple hydrophobic pockets spanning both the S1 and S2 subunits of the S protein.Molecular simulations validated by a microscale thermophoresis binding assay revealed that LPS binds to the S2 pocket with a lower affinity compared to S1,suggesting a role as an intermediate in LPS transfer.Congruently,nuclear factor-kappa B(NF-kB)activation in monocytic THP-1 cells is strongly boosted by S2.Using NF-kB reporter mice followed by bioimaging,a boosting effect was observed for both S1 and S2,with the former potentially facilitated by proteolysis.The Omicron S variant binds to LPS,but with reduced affinity and LPS boosting in vitro and in vivo.Taken together,the data provide a molecular mechanism by which S protein augments LPS-mediated hyperinflammation.
