Objective The prevalence of carbapenem-resistant Klebsiella pneumoniae(CR-KP)is a global public health problem.It is mainly caused by the plasmid-carried carbapenemase gene.Outer membrane vesicles(OMVs)contain toxins ...Objective The prevalence of carbapenem-resistant Klebsiella pneumoniae(CR-KP)is a global public health problem.It is mainly caused by the plasmid-carried carbapenemase gene.Outer membrane vesicles(OMVs)contain toxins and other factors involved in various biological processes,includingβ-lactamase and antibiotic-resistance genes.This study aimed to reveal the transmission mechanism of OMV-mediated drug resistance of Klebsiella(K.)pneumoniae.Methods We selected CR-KP producing K.pneumoniae carbapenemase-2(KPC-2)to study whether they can transfer resistance genes through OMVs.The OMVs of CR-KP were obtained by ultracentrifugation,and incubated with carbapenem-sensitive K.pneumoniae for 4 h.Finally,the carbapenem-sensitive K.pneumoniae was tested for the presence of bla_(KPC-2)resistance gene and its sensitivity to carbapenem antibiotics.Results The existence of OMVs was observed by the electron microscopy.The extracted OMVs had bla_(KPC-2)resistance gene.After incubation with OMVs,bla_(KPC-2)resistance gene was detected in sensitive K.pneumoniae,and it became resistant to imipenem and meropenem.Conclusion This study demonstrated that OMVs isolated from KPC-2-producing CR-KP could deliver bla_(KPC-2)to sensitive K.pneumoniae,allowing the bacteria to produce carbapenemase,which may provide a novel target for innovative therapies in combination with conventional antibiotics for treating carbapenem-resistant Enterobacteriaceae.展开更多
Vibrio splendidus is an important opportunistic pathogen ubiquitously present in the marine environment,exhibiting virulence to a variety of cultured animals.The extracellular products secreted by V.splendidus are cru...Vibrio splendidus is an important opportunistic pathogen ubiquitously present in the marine environment,exhibiting virulence to a variety of cultured animals.The extracellular products secreted by V.splendidus are crucial to bacterial survival and virulence.In this study,the secretion of outer membrane vesicles(OMVs)by V.splendidus was determined,purified,and morphologically characterized.The protein composition of OMVs was analyzed by proteomic analysis.The results showed that approximately 120 proteins were contained in these OMVs,including outer membrane proteins,flagellins,ABC transporters,protease,and iron regulation proteins,etc.,which were involved in bacterial motility,formation of biofilms and the cell membrane components,and cellular localization based on their structural molecule activity,passive transmembrane transporter activity,channel activity,neurotransmitter receptor activity,extracellular ligand-gated ion channel activity,glutamate receptor activity,ligand-gated ion channel activity,and transmembrane signaling receptor activity.To explore the biological functions of OMVs in V.splendidus,the effects of OMVs on the bacterial adaption to iron limitation,antibiotic,and the coelomic fluid of the Apostichopus japonicus were confirmed.This study is the first time to show that V.splendidus secretes OMVs,and OMVs carry functional proteins that enhance bacterial survival under various stresses.展开更多
Bacterial outer membrane vesicles(OMVs)are potent immunostimulants of regulating the tumor microenvironment(TME)for immunotherapy,and can be used to deliver drugs.However,the severe systemic inflammatory response trig...Bacterial outer membrane vesicles(OMVs)are potent immunostimulants of regulating the tumor microenvironment(TME)for immunotherapy,and can be used to deliver drugs.However,the severe systemic inflammatory response triggered by OMVs upon intravenous(i.v.)injection has limited their application.Here,we developed a safe and effective strategy by conjugating doxorubicin-loaded serum albumin(SA-DOX,AD)onto the surface of OMVs using a matrix metalloproteinase(MMP)-cleavable peptide linker(cL).This approach enabled the dynamic shielding of OMVs to reduce the systemic side effects while simultaneously enhancing the anti-tumor effects through chemo-immunotherapy.Specifically,the resulting OMV-cL-AD formulation exhibited significantly enhanced accumulation at the tumor site after i.v.administration,facilitated by the SA decoration on the OMVs surface.Subsequently,the shield on the OMV-cL-AD was cleaved by the over-expressed MMP in the TME,leading to the release of both OMVs and AD.This process provided OMV-induced immunotherapy and DOX-induced chemotherapy,resulting in synergistic tumor inhibition.In conclusion,our work demonstrated the potential of OMV-cL-AD as an effective immunochemotherapy strategy that can prolong the survival time of mice without inducing side effects.展开更多
Noncoding small RNAs(sRNAs)packaged in bacterial outer membrane vesicles(OMVs)function as novel mediators of interspecies communication.While the role of bacterial sRNAs in enhancing virulence is well established,the ...Noncoding small RNAs(sRNAs)packaged in bacterial outer membrane vesicles(OMVs)function as novel mediators of interspecies communication.While the role of bacterial sRNAs in enhancing virulence is well established,the role of sRNAs in the interaction between OMVs from phytopathogenic bacteria and their host plants remains unclear.In this study,we employ RNA sequencing to characterize differentially pack-aged sRNAs in OMVs of the phytopathogen Xanthomonas oryzae pv.oryzicola(Xoc).Our candidate sRNA(Xosr001)was abundant in OMVs and involved in the regulation of OsJMT1 to impair host stomatal immu-nity.Xoc loads Xosr001 into OMVs,which are specifically ttransferred into the mechanical tissues of rice leaves.Xosr001 suppresses OsJMT1 transcript accumulation in vivo,leading to a reduction in MeJA accu-mulation in rice leaves.Furthermore,the application of synthesized Xosr001 sRNA to the leaves of OsJMT1-HA-OE transgenic line results in the suppression of OsJMT1 expression by Xosr001.Notably,the OsJMT1-HA-OE transgenic line exhibited attenuated stomatal immunity and disease susceptibility upon infection with DXosr001 compared to Xoc.These results suggest that Xosr001 packaged in Xoc OMVs functions to suppress stomatal immunity in rice.展开更多
Tumor vaccines,a type of personalized tumor immunotherapy,have developed rapidly in recent decades.These vaccines evoke tumor antigen-specific T cells to achieve immune recognition and killing of tumor cells.Because t...Tumor vaccines,a type of personalized tumor immunotherapy,have developed rapidly in recent decades.These vaccines evoke tumor antigen-specific T cells to achieve immune recognition and killing of tumor cells.Because the immunogenicity of tumor antigens alone is insufficient,immune adjuvants and nanocarriers are often required to enhance anti-tumor immune responses.At present,vaccine carrier development often integrates nanocarriers and immune adjuvants.Among them,outer membrane vesicles(OMVs)are receiving increasing attention as a delivery platform for tumor vaccines.OMVs are natural nanovesicles derived from Gramnegative bacteria,which have adjuvant function because they contain pathogen associated molecular patterns.Importantly,OMVs can be functionally modified by genetic engineering of bacteria,thus laying a foundation for applications as a delivery platform for tumor nanovaccines.This review summarizes 5 aspects of recent progress in,and future development of,OMV-based tumor nanovaccines:strain selection,heterogeneity,tumor antigen loading,immunogenicity and safety,and mass production of OMVs.展开更多
Bacterial outer membrane vesicles(OMVs)are potent immuno-stimulating agents and have the potentials to be bioengineered as platforms for antitumor nanomedicine.In this study,OMVs are demonstrated as promising antitumo...Bacterial outer membrane vesicles(OMVs)are potent immuno-stimulating agents and have the potentials to be bioengineered as platforms for antitumor nanomedicine.In this study,OMVs are demonstrated as promising antitumor therapeutics.OMVs can lead to beneficial M2-to-M1 polarization of macrophages and induce pyroptosis to enhance antitumor immunity,but the therapeutic window of OMVs is narrow for its toxicity.We propose a bioengineering strategy to enhance the tumor-targeting ability of OMVs by macrophage-mediated delivery and improve the antitumor efficacy by co-loading of photosensitizer chlorin e6(Ce6)and chemotherapeutic drug doxorubicin(DOX)into OMVs as a therapeutic platform.We demonstrate that systemic injection of the DOX/Ce6-OMVs@M therapeutic platform,providing combinational photodynamic/chemo-/immunotherapy,eradicates triple-negative breast tumors in mice without side effects.Importantly,this strategy also effectively prevents tumor metastasis to the lung.This OMVs-based strategy with bioengineering may serve as a powerful therapeutic platform for a synergic antitumor therapy.展开更多
Rapid detection and quantification of outer membrane vesicle(OMV)are of both scientific value and clinical implications.However,limited tools are available for investigations of OMVs.Herein,we report a novel fluoresce...Rapid detection and quantification of outer membrane vesicle(OMV)are of both scientific value and clinical implications.However,limited tools are available for investigations of OMVs.Herein,we report a novel fluorescent probe with aggregation-induced emission(AIE)characteristics,namely,OEO-TPE-MEM(OTM),for OMV detection.OTM emits faintly in an aqueous medium,but its fluorescence could be effectively turned on upon interacting with bacteria bodies and OMVs produced by Gram-negative bacteria.Notably,OTM could provide quantitative information on bacterial membrane remodeling and OMV secretion and be applied to high-throughput screening of OMV-inducing agents.This study presents a powerful AIE probe for imaging and quantitative analysis of bacteria envelop and derived OMVs,which might be applied for evaluating research and clinical antimicrobial materials in future studies.展开更多
基金supported by the National Natural Science Foundation of China(No.31771189)the Wuhan Health Commission(No.WX18C17 and No.WX19Q31)the Natural Science Foundation of Hubei Province,China(No.2017CFA065 and No.WJ2019H378).
文摘Objective The prevalence of carbapenem-resistant Klebsiella pneumoniae(CR-KP)is a global public health problem.It is mainly caused by the plasmid-carried carbapenemase gene.Outer membrane vesicles(OMVs)contain toxins and other factors involved in various biological processes,includingβ-lactamase and antibiotic-resistance genes.This study aimed to reveal the transmission mechanism of OMV-mediated drug resistance of Klebsiella(K.)pneumoniae.Methods We selected CR-KP producing K.pneumoniae carbapenemase-2(KPC-2)to study whether they can transfer resistance genes through OMVs.The OMVs of CR-KP were obtained by ultracentrifugation,and incubated with carbapenem-sensitive K.pneumoniae for 4 h.Finally,the carbapenem-sensitive K.pneumoniae was tested for the presence of bla_(KPC-2)resistance gene and its sensitivity to carbapenem antibiotics.Results The existence of OMVs was observed by the electron microscopy.The extracted OMVs had bla_(KPC-2)resistance gene.After incubation with OMVs,bla_(KPC-2)resistance gene was detected in sensitive K.pneumoniae,and it became resistant to imipenem and meropenem.Conclusion This study demonstrated that OMVs isolated from KPC-2-producing CR-KP could deliver bla_(KPC-2)to sensitive K.pneumoniae,allowing the bacteria to produce carbapenemase,which may provide a novel target for innovative therapies in combination with conventional antibiotics for treating carbapenem-resistant Enterobacteriaceae.
基金the Zhejiang Provincial Natural Science Foundation for Distinguished Young Scholars(No.LR20C190001)the National Natural Science Foundation of China(No.31972833)+1 种基金the Fundamental Research Funds for the Provincial Universities of Zhejiang(No.SJ LZ2020001)the K.C.Wong Magna Fund at Ningbo University。
文摘Vibrio splendidus is an important opportunistic pathogen ubiquitously present in the marine environment,exhibiting virulence to a variety of cultured animals.The extracellular products secreted by V.splendidus are crucial to bacterial survival and virulence.In this study,the secretion of outer membrane vesicles(OMVs)by V.splendidus was determined,purified,and morphologically characterized.The protein composition of OMVs was analyzed by proteomic analysis.The results showed that approximately 120 proteins were contained in these OMVs,including outer membrane proteins,flagellins,ABC transporters,protease,and iron regulation proteins,etc.,which were involved in bacterial motility,formation of biofilms and the cell membrane components,and cellular localization based on their structural molecule activity,passive transmembrane transporter activity,channel activity,neurotransmitter receptor activity,extracellular ligand-gated ion channel activity,glutamate receptor activity,ligand-gated ion channel activity,and transmembrane signaling receptor activity.To explore the biological functions of OMVs in V.splendidus,the effects of OMVs on the bacterial adaption to iron limitation,antibiotic,and the coelomic fluid of the Apostichopus japonicus were confirmed.This study is the first time to show that V.splendidus secretes OMVs,and OMVs carry functional proteins that enhance bacterial survival under various stresses.
基金supported by the Beijing Natural Science Foundation(No.JQ21027)the National Natural Science Foundation of China(Nos.U2001224,32030062,21821005,and 82202028).
文摘Bacterial outer membrane vesicles(OMVs)are potent immunostimulants of regulating the tumor microenvironment(TME)for immunotherapy,and can be used to deliver drugs.However,the severe systemic inflammatory response triggered by OMVs upon intravenous(i.v.)injection has limited their application.Here,we developed a safe and effective strategy by conjugating doxorubicin-loaded serum albumin(SA-DOX,AD)onto the surface of OMVs using a matrix metalloproteinase(MMP)-cleavable peptide linker(cL).This approach enabled the dynamic shielding of OMVs to reduce the systemic side effects while simultaneously enhancing the anti-tumor effects through chemo-immunotherapy.Specifically,the resulting OMV-cL-AD formulation exhibited significantly enhanced accumulation at the tumor site after i.v.administration,facilitated by the SA decoration on the OMVs surface.Subsequently,the shield on the OMV-cL-AD was cleaved by the over-expressed MMP in the TME,leading to the release of both OMVs and AD.This process provided OMV-induced immunotherapy and DOX-induced chemotherapy,resulting in synergistic tumor inhibition.In conclusion,our work demonstrated the potential of OMV-cL-AD as an effective immunochemotherapy strategy that can prolong the survival time of mice without inducing side effects.
基金supported by the National Natural Science Foundation of China (32272479,32200142)Open Project Program of State Key Laboratory of Rice Biology (20190109)+3 种基金Open Project Program of State Key Laboratory for Biology of Plant Diseases and Insect Pests (SKLOF202201)Zhejiang Province Ecological Environment Research and Promotion Project (2020HT0009)Shanghai Committee of Science and Technology (19390743300 and 21ZR1435500)Chongqing Natural Science Foundation (CSTB2022NSCQ-MSX0524).
文摘Noncoding small RNAs(sRNAs)packaged in bacterial outer membrane vesicles(OMVs)function as novel mediators of interspecies communication.While the role of bacterial sRNAs in enhancing virulence is well established,the role of sRNAs in the interaction between OMVs from phytopathogenic bacteria and their host plants remains unclear.In this study,we employ RNA sequencing to characterize differentially pack-aged sRNAs in OMVs of the phytopathogen Xanthomonas oryzae pv.oryzicola(Xoc).Our candidate sRNA(Xosr001)was abundant in OMVs and involved in the regulation of OsJMT1 to impair host stomatal immu-nity.Xoc loads Xosr001 into OMVs,which are specifically ttransferred into the mechanical tissues of rice leaves.Xosr001 suppresses OsJMT1 transcript accumulation in vivo,leading to a reduction in MeJA accu-mulation in rice leaves.Furthermore,the application of synthesized Xosr001 sRNA to the leaves of OsJMT1-HA-OE transgenic line results in the suppression of OsJMT1 expression by Xosr001.Notably,the OsJMT1-HA-OE transgenic line exhibited attenuated stomatal immunity and disease susceptibility upon infection with DXosr001 compared to Xoc.These results suggest that Xosr001 packaged in Xoc OMVs functions to suppress stomatal immunity in rice.
基金supported by grants from the National Key R&D Program of China(Grant No.2021YFA0909900,X.Z.)the CAS Project for Young Scientists in Basic Research(Grant No.YSBR-010,X.Z.)+2 种基金the Beijing Natural Science Foundation(Grant No.Z200020,X.Z.)the Beijing Nova Program(Grant No.Z201100006820031,X.Z.)the National Natural Science Foundation of China(Grant No.32171384,X.Z.).
文摘Tumor vaccines,a type of personalized tumor immunotherapy,have developed rapidly in recent decades.These vaccines evoke tumor antigen-specific T cells to achieve immune recognition and killing of tumor cells.Because the immunogenicity of tumor antigens alone is insufficient,immune adjuvants and nanocarriers are often required to enhance anti-tumor immune responses.At present,vaccine carrier development often integrates nanocarriers and immune adjuvants.Among them,outer membrane vesicles(OMVs)are receiving increasing attention as a delivery platform for tumor vaccines.OMVs are natural nanovesicles derived from Gramnegative bacteria,which have adjuvant function because they contain pathogen associated molecular patterns.Importantly,OMVs can be functionally modified by genetic engineering of bacteria,thus laying a foundation for applications as a delivery platform for tumor nanovaccines.This review summarizes 5 aspects of recent progress in,and future development of,OMV-based tumor nanovaccines:strain selection,heterogeneity,tumor antigen loading,immunogenicity and safety,and mass production of OMVs.
基金supported by the Hunan Provincial Science and Technology Plan(No.2016TP2002).
文摘Bacterial outer membrane vesicles(OMVs)are potent immuno-stimulating agents and have the potentials to be bioengineered as platforms for antitumor nanomedicine.In this study,OMVs are demonstrated as promising antitumor therapeutics.OMVs can lead to beneficial M2-to-M1 polarization of macrophages and induce pyroptosis to enhance antitumor immunity,but the therapeutic window of OMVs is narrow for its toxicity.We propose a bioengineering strategy to enhance the tumor-targeting ability of OMVs by macrophage-mediated delivery and improve the antitumor efficacy by co-loading of photosensitizer chlorin e6(Ce6)and chemotherapeutic drug doxorubicin(DOX)into OMVs as a therapeutic platform.We demonstrate that systemic injection of the DOX/Ce6-OMVs@M therapeutic platform,providing combinational photodynamic/chemo-/immunotherapy,eradicates triple-negative breast tumors in mice without side effects.Importantly,this strategy also effectively prevents tumor metastasis to the lung.This OMVs-based strategy with bioengineering may serve as a powerful therapeutic platform for a synergic antitumor therapy.
基金Ming Wai Lau Centre for Reparative MedicineKarolinska Institutet+2 种基金Innovation and Technology Commission,Grant/Award Number:MHP/047/19Research Grants Council of Hong Kong,Grant/Award Number:C6014-20WNational Natural Science Foundation of China,Grant/Award Number:22005050。
文摘Rapid detection and quantification of outer membrane vesicle(OMV)are of both scientific value and clinical implications.However,limited tools are available for investigations of OMVs.Herein,we report a novel fluorescent probe with aggregation-induced emission(AIE)characteristics,namely,OEO-TPE-MEM(OTM),for OMV detection.OTM emits faintly in an aqueous medium,but its fluorescence could be effectively turned on upon interacting with bacteria bodies and OMVs produced by Gram-negative bacteria.Notably,OTM could provide quantitative information on bacterial membrane remodeling and OMV secretion and be applied to high-throughput screening of OMV-inducing agents.This study presents a powerful AIE probe for imaging and quantitative analysis of bacteria envelop and derived OMVs,which might be applied for evaluating research and clinical antimicrobial materials in future studies.
