Circular RNAs are a large class of noncoding RNAs.Smad5 functions in cell differentiation,cell proliferation and metastasis.It has been reported that lnc-Smad5 can inhibit the proliferation of diffuse large B cell lym...Circular RNAs are a large class of noncoding RNAs.Smad5 functions in cell differentiation,cell proliferation and metastasis.It has been reported that lnc-Smad5 can inhibit the proliferation of diffuse large B cell lymphoma.However,the function of circ-Smad5 has not yet been reported.Lentivirus vectors were constructed to establish circ-Smad5 upregulated and circ-Smad5 downregulated cell models.A CCK-8 assay was used to detect the proliferation of JB6 cells.FACS was used to analyze the cell cycle in the cell models.Western blot,immunofluorescence staining and TOP/FOP flash dual luciferase activity assays were used to determine the activity of the Wnt signaling pathway.The results revealed that the expression level of circ-Smad5 in JB6 cells was significantly lower than the expression level of linearizedSmad5.Compared with the control group,the percentage of S phase cells and the expression level of cyclin D1 protein were significantly higher in the sh-circ-Smad5 group.In the sh-circSmad5 group,b-catenin and LEF-1 were significantly increased,p-b-catenin was significantly decreased,and the relative activity of the TOP/FOP reporter gene was higher compared to the control group levels.These phenomena could be reversed by treating with Wnt signaling inhibitor PNU-74654.We conclude that the circ-Smad5 retards the proliferation and the cell cycle progression of JB6 cells.Thus,circ-Smad5 may function by inhibiting the activation of Wnt/b-catenin/Lef 1 signaling,which inhibits the expression of cyclin D1.To the best of our knowledge,we are the first to report the function of circ-Smad5.展开更多
SARS-CoV-2 mutations contribute to increased viral transmissibility and immune escape,compromising the effectiveness of existing vaccines and neutralizing antibodies.An in-depth investigation on COVID-19 pathogenesis ...SARS-CoV-2 mutations contribute to increased viral transmissibility and immune escape,compromising the effectiveness of existing vaccines and neutralizing antibodies.An in-depth investigation on COVID-19 pathogenesis is urgently needed to develop a strategy against SARS-CoV-2 variants.Here,we identified CD147 as a universal receptor for SARS-CoV-2 and its variants.Meanwhile,Meplazeumab,a humanized anti-CD147 antibody,could block cellular entry of SARS-CoV-2 and its variants-alpha,beta,gamma,and delta,with inhibition rates of 68.7,75.7,52.1,52.1,and 62.3%at 60μg/ml,respectively.Furthermore,humanized CD147 transgenic mice were susceptible to SARS-CoV-2 and its two variants,alpha and beta.When infected,these mice developed exudative alveolar pneumonia,featured by immune responses involving alveoli-infiltrated macrophages,neutrophils,and lymphocytes and activation of IL-17 signaling pathway.Mechanistically,we proposed that severe COVID-19-related cytokine storm is induced by a"spike protein-CD147-CyPA signaling axis":Infection of SARS-CoV-2 through CD147 initiated the JAK-STAT pathway,which further induced expression of cyclophilin A(CyPA);CyPA reciprocally bound to CD147 and triggered MAPK pathway.Consequently,the MAPK pathway regulated the expression of cytokines and chemokines,which promoted the development of cytokine storm.Importantly,Meplazumab could effectively inhibit viral entry and inflammation caused by SARS-CoV-2 and its variants.Therefore,our findings provided a new perspective for severe COVID-19-related pathogenesis.Furthermore,the validated universal receptor for SARS-CoV-2 and its variants can be targeted for COVID-19 treatment.展开更多
COVID‐19 patients can develop clinical and histopathological features associated with fibrosis,but the pathogenesis of fibrosis remains poorly understood.CD147 has been identified as a universal receptor for SARS-CoV...COVID‐19 patients can develop clinical and histopathological features associated with fibrosis,but the pathogenesis of fibrosis remains poorly understood.CD147 has been identified as a universal receptor for SARS-CoV-2 and its variants,which could initiate COVID-19-related cytokine storm.Here,we systemically analyzed lung pathogenesis in SARS-CoV-2-and its delta variant-infected humanized CD147 transgenic mice.Histopathology and Transmission Electron Microscopy revealed inflammation,fibroblast expansion and pronounced fibrotic remodeling in SARS-CoV-2-infected lungs.Consistently,RNA-sequencing identified a set of fibrosis signature genes.Furthermore,we identified CD147 as a crucial regulator for fibroblast activation induced by SARS-CoV-2.We found conditional knockout of CD147 in fibroblast suppressed activation of fibroblasts,decreasing susceptibility to bleomycin-induced pulmonary fibrosis.Meplazumab,a CD147 antibody,was able to inhibit the accumulation of activated fibroblasts and the production of ECM proteins,thus alleviating the progression of pulmonary fibrosis caused by SARS-CoV-2.In conclusion,we demonstrated that CD147 contributed to SARS-CoV-2-triggered progressive pulmonary fibrosis and identified CD147 as a potential therapeutic target for treating patients with post-COVID-19 pulmonary fibrosis.展开更多
基金supported by the National Natural Science Foundation of China[grant number 81472895]the Natural Science Foundation of Chongqing[grant number cstc2018jcyjAX0053]Key Talents Support Plan of Army Medical University(2019).We thank Min Gao and Yizhan Xing at the Army Medical University for technical support.
文摘Circular RNAs are a large class of noncoding RNAs.Smad5 functions in cell differentiation,cell proliferation and metastasis.It has been reported that lnc-Smad5 can inhibit the proliferation of diffuse large B cell lymphoma.However,the function of circ-Smad5 has not yet been reported.Lentivirus vectors were constructed to establish circ-Smad5 upregulated and circ-Smad5 downregulated cell models.A CCK-8 assay was used to detect the proliferation of JB6 cells.FACS was used to analyze the cell cycle in the cell models.Western blot,immunofluorescence staining and TOP/FOP flash dual luciferase activity assays were used to determine the activity of the Wnt signaling pathway.The results revealed that the expression level of circ-Smad5 in JB6 cells was significantly lower than the expression level of linearizedSmad5.Compared with the control group,the percentage of S phase cells and the expression level of cyclin D1 protein were significantly higher in the sh-circ-Smad5 group.In the sh-circSmad5 group,b-catenin and LEF-1 were significantly increased,p-b-catenin was significantly decreased,and the relative activity of the TOP/FOP reporter gene was higher compared to the control group levels.These phenomena could be reversed by treating with Wnt signaling inhibitor PNU-74654.We conclude that the circ-Smad5 retards the proliferation and the cell cycle progression of JB6 cells.Thus,circ-Smad5 may function by inhibiting the activation of Wnt/b-catenin/Lef 1 signaling,which inhibits the expression of cyclin D1.To the best of our knowledge,we are the first to report the function of circ-Smad5.
基金supported by the National Science and Technology Major Project of China(2019ZX09732-001)the Key R&D Plan Projects in Shaanxi Province(2020ZDXM2-SF-01)the Young Talent Fund of the University Association for Science and Technology in Shaanxi,China(20200304).
文摘SARS-CoV-2 mutations contribute to increased viral transmissibility and immune escape,compromising the effectiveness of existing vaccines and neutralizing antibodies.An in-depth investigation on COVID-19 pathogenesis is urgently needed to develop a strategy against SARS-CoV-2 variants.Here,we identified CD147 as a universal receptor for SARS-CoV-2 and its variants.Meanwhile,Meplazeumab,a humanized anti-CD147 antibody,could block cellular entry of SARS-CoV-2 and its variants-alpha,beta,gamma,and delta,with inhibition rates of 68.7,75.7,52.1,52.1,and 62.3%at 60μg/ml,respectively.Furthermore,humanized CD147 transgenic mice were susceptible to SARS-CoV-2 and its two variants,alpha and beta.When infected,these mice developed exudative alveolar pneumonia,featured by immune responses involving alveoli-infiltrated macrophages,neutrophils,and lymphocytes and activation of IL-17 signaling pathway.Mechanistically,we proposed that severe COVID-19-related cytokine storm is induced by a"spike protein-CD147-CyPA signaling axis":Infection of SARS-CoV-2 through CD147 initiated the JAK-STAT pathway,which further induced expression of cyclophilin A(CyPA);CyPA reciprocally bound to CD147 and triggered MAPK pathway.Consequently,the MAPK pathway regulated the expression of cytokines and chemokines,which promoted the development of cytokine storm.Importantly,Meplazumab could effectively inhibit viral entry and inflammation caused by SARS-CoV-2 and its variants.Therefore,our findings provided a new perspective for severe COVID-19-related pathogenesis.Furthermore,the validated universal receptor for SARS-CoV-2 and its variants can be targeted for COVID-19 treatment.
基金National Natural Science Foundation of China(92169211,82022059)National Natural Science Fund for Excellent Young Scientists Fund Program(Overseas)+1 种基金Key R&D Plan Projects in Shaanxi Province(2020ZDXM2-SF-01)Young Elite Scientist Sponsorship Program by Cast of China Association for Science and Technology(YESS20200011).
文摘COVID‐19 patients can develop clinical and histopathological features associated with fibrosis,but the pathogenesis of fibrosis remains poorly understood.CD147 has been identified as a universal receptor for SARS-CoV-2 and its variants,which could initiate COVID-19-related cytokine storm.Here,we systemically analyzed lung pathogenesis in SARS-CoV-2-and its delta variant-infected humanized CD147 transgenic mice.Histopathology and Transmission Electron Microscopy revealed inflammation,fibroblast expansion and pronounced fibrotic remodeling in SARS-CoV-2-infected lungs.Consistently,RNA-sequencing identified a set of fibrosis signature genes.Furthermore,we identified CD147 as a crucial regulator for fibroblast activation induced by SARS-CoV-2.We found conditional knockout of CD147 in fibroblast suppressed activation of fibroblasts,decreasing susceptibility to bleomycin-induced pulmonary fibrosis.Meplazumab,a CD147 antibody,was able to inhibit the accumulation of activated fibroblasts and the production of ECM proteins,thus alleviating the progression of pulmonary fibrosis caused by SARS-CoV-2.In conclusion,we demonstrated that CD147 contributed to SARS-CoV-2-triggered progressive pulmonary fibrosis and identified CD147 as a potential therapeutic target for treating patients with post-COVID-19 pulmonary fibrosis.
