Severe Acute Respiratory Syndrome （SARS） is a deadly infectious disease caused by SARS Coronavirus （SARS-CoV）. Inactivated SARS-CoV has been explored as a vaccine against SARS-CoV. However, safe and potent adjuvan...Severe Acute Respiratory Syndrome （SARS） is a deadly infectious disease caused by SARS Coronavirus （SARS-CoV）. Inactivated SARS-CoV has been explored as a vaccine against SARS-CoV. However, safe and potent adjuvants, especially with more efficient and economical needle-free vaccination are alw needed more urgently in a pandemic. The development of a safe and effective mucosal adjuvant and vaccine ays for prevention of emergent infectious diseases such as SARS will be an important advancement. PIKA, a stabilized derivative of Poly （I：C）, was previously reported to be safe and potent as adjuvant in mouse models. In the present study, we demonstrated that the intraperitoneal and intranasal co-administration of inactivated SARS-CoV vaccine together with this improved Poly （I：C） derivative induced strong anti-SARS-CoV mucosal and systemic humoral immune responses with neutralizing activity against pseudotyped virus. Although intraperitoneal immunization of inactivated SARS-CoV vaccine alone could induce a certain level of neutralizing activity in serum as well as in mucosal sites, co-administration of inactivated SARS-CoV vaccine with PIKA as adjuvant could induce a much higher neutralizing activity. When intranasal immunization was used, PIKA was obligatorily for inducing neutralizing activity in serum as well as in mucosal sites and was correlated with both mucosal IgA and mucosal IgG response. Overall, PIKA could be a good mucosal adjuvant candidate for inactivated SARS-CoV vaccine for use in possible future pandemic.展开更多
For subunit vaccines,adjuvants play a key role in shaping the magnitude,persistence and form of targeted antigen-specific immune response.Flagellin is a potent immune activator by bridging innate inflammatory response...For subunit vaccines,adjuvants play a key role in shaping the magnitude,persistence and form of targeted antigen-specific immune response.Flagellin is a potent immune activator by bridging innate inflammatory responses and adaptive immunity and an adjuvant candidate for clinical application.Calcium phosphate nanoparticles are efficient carriers for different biomolecules like DNA,RNA,peptides and proteins.Flagellin-functionalized calcium phosphate nanoparticles were prepared and their immunostimulatory effect on the innate immune system,i.e.the cytokine production,was studied.They induced the production of the proinflammatory cytokines IL-8 （Caco-2 cells） and IL-1β（bone marrow-derived macrophages; BMDM） in vitro and IL-6 in vivo after intraperitoneal injection in mice.The immunostimulation was more pronounced than with free flagellin.展开更多
Although IL-12 plays a critical role in priming Th1 and cytotoxic T lymphocyte(CTL) responses, Toll-like receptor(TLR) signaling only induces low amounts of IL-12 in dendritic cells and macrophages, implying the exist...Although IL-12 plays a critical role in priming Th1 and cytotoxic T lymphocyte(CTL) responses, Toll-like receptor(TLR) signaling only induces low amounts of IL-12 in dendritic cells and macrophages, implying the existence of stringent regulatory mechanisms. In this study, we sought to uncover the mechanisms underlying TLR-induced IL-12 expression and the Th1 response. By systemic screening, we identified a number of protein kinases involved in the regulation of TLRinduced IL-12 expression. In particular, PI3 K, ERK, and m TOR play critical roles in the TLR-induced Th1 response by regulating IL-12 and IL-10 production in innate immune cells. Moreover, we identified c-fos as a key molecule that mediates m TOR-regulated IL-12 and IL-10 expression in TLR signaling. Mechanistically, m TOR plays a crucial role in c-fos expression, thereby modulating NFκB binding to promoters of IL-12 and IL-10. By controlling the expression of a special innate gene program, m TOR can specifically regulate the TLR-induced T cell response in vivo. Furthermore, blockade of m TOR by rapamycin efficiently boosted TLR-induced antigen-specific T and B cell responses to HBV and HCV vaccines. Taken together, these results reveal a novel mechanism through which m TOR regulates TLR-induced IL-12 and IL-10 production, contributing new insights for strategies to improve vaccine efficacy.展开更多
Enterovirus 71(EV71) infection causes severe central nervous system damage, particularly for children under the age of 5 years old, which remains a major public health burden worldwide. Clinical data released that chi...Enterovirus 71(EV71) infection causes severe central nervous system damage, particularly for children under the age of 5 years old, which remains a major public health burden worldwide. Clinical data released that children may be repeatedly infected by different members in enterovirus and get even worsen. Mucosa, especially epithelium of alimentary canal, was considered the primary site of EV71 infection. It has been elusive whether the preexsiting viral antibody in mucosa plays a role in EV71 infection. To answer this question, we respectively measured viral antibody response and EV71 RNA copy number of one hundred throat swab specimens from clinically confirmed EV71-infected children. The results released that low-level of mucosal Ig G antibody against EV71 broadly existed in young population. More importantly, it further elucidated that the children with mucosal preexsiting EV71 Ig G were prone to be infected, which suggested a former viral Ig G mediated enhancement of viral infection in vivo.展开更多
Dental caries remains one of the most common global chronic diseases caused by Streptococcus mutans,which is prevalent all over the world.The caries prevalence of children aged between 5-6 years old in China is still ...Dental caries remains one of the most common global chronic diseases caused by Streptococcus mutans,which is prevalent all over the world.The caries prevalence of children aged between 5-6 years old in China is still in very high rate.A potent and effective anti-caries vaccine has long been expected for caries prevention but no vaccines have been brought to market till now mainly due to the low ability to induce and maintain protective antibody in oral fluids.This review will give a brief historical retrospect on study of dental caries and pathogenesis,effective targets for anti-caries vaccines,oral immune system and immunization against dental caries.Then,salivary IgA antibodies and the protective responses are discussed in the context of the ontogeny of mucosal immunity to indigenous oral streptococcal.The methods and advancement for induction of specific anticaries salivary sIgA antibodies and enhancement of specific anti-caries salivary sIgA antibodies by intranasal immunization with a safe effective mucosal adjuvant are described.The progress in the enhancement of salivary sIgA antibodies and anticaries protection by intranasal immunization with flagellin-PAc fusion protein will be highlighted.Finally,some of the main strategies that have been used for successful mucosal vaccination of caries vaccine are reviewed,followed by discussion of the mucosal adjuvant choice for achieving protective immunity at oral mucosal membranes for development of a nasal-spray or nasal-drop anti-caries vaccine for human.展开更多
Flagellin is a potent activator of a broad range of cell types that are involved in innate and adaptive immunity. Therefore, it is a good adjuvant candidate for vaccines, and it might function as a biological protecta...Flagellin is a potent activator of a broad range of cell types that are involved in innate and adaptive immunity. Therefore, it is a good adjuvant candidate for vaccines, and it might function as a biological protectant against both major acute radiation syndrome during cancer radiotherapy and a mitigator of radiation emergencies. However, accumulating evidence has implicated flagellin in the occurrence of some inflammatory diseases, such as acute lung inflammation, cardiovascular collapse and inflammatory bowel disease. The aim of this study was to elucidate whether only flagellin-TLR5 signaling activation plays a role in the pathophysiology of liver or whether some other flagellin activity also contributes to liver injury either via bacterial infections or during clinical applications. Recombinant flagellin proteins with or without TLR5-stimulating activity were used to evaluate the role of flagellin-TLR5 signaling in liver injury in wild-type and TLR5 KO mice. Gross lesions and large areas of hepatocellular necrosis were observed in liver tissue 12 h after the intraperitoneal administration of 100 or 200 pg flagellin （FliC） in a dose-and time-dependent manner in wild-type mice, but not in TLR5 KO mice. Deletion of the N-terminal or TLR5 binding domain of flagellin inhibited flagellin-induced inflammatory responses and the subsequent acute liver function abnormality and damage. These data confirmed that flagellin is an essential determinant of liver injury and demonstrated that the over-activation of TLR5 signaling by high-dose flagellin caused acute inflammatory responses, neutrophil accumulation and oxidative stress in the liver, which contributes to the progression and severity of flagellin-induced liver injury.展开更多
Bacterial flagellin is a unique pathogen-associated molecular pattern （PAMP）, which can be recognized by surface localized Toll-like receptor 5 （TLR5） and the cytosolic NOD-like receptor （NLR） protein 4 （NLRC4...Bacterial flagellin is a unique pathogen-associated molecular pattern （PAMP）, which can be recognized by surface localized Toll-like receptor 5 （TLR5） and the cytosolic NOD-like receptor （NLR） protein 4 （NLRC4） receptors. Activation of the TLR5 and/or NLRC4 signaling pathways by flagellin and the resulting immune responses play important roles in anti-bacterial immunity. However, it remains unclear how the dual activities of flagellin that activate the TLR5 and/or NLRC4 signaling pathways orchestrate the immune responses. In this study, we assessed the effects of flagellin and its mutants lacking the ability to activate TLR5 and NLRC4 alone or in combination on the adaptive immune responses against flagellin. Flagellin that was unable to activate NLRC4 induced a significantly higher antibody response than did wild-type flagellin. The increased antibody response could be eliminated when macrophages were depleted in vivo. The activation of NLRC4 by flagellin downregulated the flagellin-induced and TLR5-mediated immune responses against flagellin.展开更多
The innate immune system plays an essential role in the host defense against infections by initially sensing and recognizing diverse microbial pathogens and directing adaptive immune responses to their infections.How ...The innate immune system plays an essential role in the host defense against infections by initially sensing and recognizing diverse microbial pathogens and directing adaptive immune responses to their infections.How does the innate immune system sense and recognize pathogens?The identification of pattern recognition receptors(PRRs)during the past decades has brought us into a new era to explore this fundamental question.PRRs are an array of germline-encoded multifunctional proteins that do not recognize specific pathogens but rather recognize conserved molecular patterns associated with various classes of pathogens,leading to pathogen-associated molecular patterns(PAMPs).展开更多
Mammals peacefully co-exist with vast numbers of different bacteria most of the time.Whether pathogenic,nonpathogenic or commensal to a mammalian host,bacteria produce microbeassociated molecular patterns(MAMPs)or pat...Mammals peacefully co-exist with vast numbers of different bacteria most of the time.Whether pathogenic,nonpathogenic or commensal to a mammalian host,bacteria produce microbeassociated molecular patterns(MAMPs)or pathogen-associated molecular patterns(PAMPs)that are recognized by multiple classes of germline-encoded pattern-recognition receptors(PRRs).Flagellin,a major structural protein of bacterial flagella,is composed of four domains(D0,D1,D2 and D3),of which the D0 and D1 domains are the most highly conserved.展开更多
The Toll-like receptor(TLR)signaling pathway,which is composed of a group of highly conserved molecules,plays a critical role in the recognition of pathogen-associated molecular patterns(PAMPs).Innate immunity activat...The Toll-like receptor(TLR)signaling pathway,which is composed of a group of highly conserved molecules,plays a critical role in the recognition of pathogen-associated molecular patterns(PAMPs).Innate immunity activated through the TLR signaling pathway serves as a first defense against infectious diseases.1 However,the exact function of TLR signaling in viral infections remains to be elucidated.展开更多
基金supported by the National Natural Science Foundation of China (30670097)National Basic Research Program of China (973 Program) (2005CB522903)+1 种基金National Key R&D Program (2007BAI28B04)National S&T Major Project on Major Infectious Diseases (2008ZX10001-010)from the Ministry of Science and Technology of the People’s Republic of China
文摘Severe Acute Respiratory Syndrome （SARS） is a deadly infectious disease caused by SARS Coronavirus （SARS-CoV）. Inactivated SARS-CoV has been explored as a vaccine against SARS-CoV. However, safe and potent adjuvants, especially with more efficient and economical needle-free vaccination are alw needed more urgently in a pandemic. The development of a safe and effective mucosal adjuvant and vaccine ays for prevention of emergent infectious diseases such as SARS will be an important advancement. PIKA, a stabilized derivative of Poly （I：C）, was previously reported to be safe and potent as adjuvant in mouse models. In the present study, we demonstrated that the intraperitoneal and intranasal co-administration of inactivated SARS-CoV vaccine together with this improved Poly （I：C） derivative induced strong anti-SARS-CoV mucosal and systemic humoral immune responses with neutralizing activity against pseudotyped virus. Although intraperitoneal immunization of inactivated SARS-CoV vaccine alone could induce a certain level of neutralizing activity in serum as well as in mucosal sites, co-administration of inactivated SARS-CoV vaccine with PIKA as adjuvant could induce a much higher neutralizing activity. When intranasal immunization was used, PIKA was obligatorily for inducing neutralizing activity in serum as well as in mucosal sites and was correlated with both mucosal IgA and mucosal IgG response. Overall, PIKA could be a good mucosal adjuvant candidate for inactivated SARS-CoV vaccine for use in possible future pandemic.
基金supported by the Deutsche Forschungsgemeinschaft(SFB/Transregio 60)the National Natural Science Foundation of China(no.81302609 and 81202312)
文摘For subunit vaccines,adjuvants play a key role in shaping the magnitude,persistence and form of targeted antigen-specific immune response.Flagellin is a potent immune activator by bridging innate inflammatory responses and adaptive immunity and an adjuvant candidate for clinical application.Calcium phosphate nanoparticles are efficient carriers for different biomolecules like DNA,RNA,peptides and proteins.Flagellin-functionalized calcium phosphate nanoparticles were prepared and their immunostimulatory effect on the innate immune system,i.e.the cytokine production,was studied.They induced the production of the proinflammatory cytokines IL-8 （Caco-2 cells） and IL-1β（bone marrow-derived macrophages; BMDM） in vitro and IL-6 in vivo after intraperitoneal injection in mice.The immunostimulation was more pronounced than with free flagellin.
基金support by National Natural Science Foundation of China grants 31070779 and 31170862 (to H.X.), 31100623 (to A.Z.) and 31270917 (to M.D.)National Key laboratory of Virology grant (2014IOV006)+3 种基金H.X. is supported by Chinese Academy of Sciences "100-talent" programNational program for returned oversea talentsthe CAS/SAFEA International Partnership Program for Creative Research TeamsShanghai Pasteur foundation
文摘Although IL-12 plays a critical role in priming Th1 and cytotoxic T lymphocyte(CTL) responses, Toll-like receptor(TLR) signaling only induces low amounts of IL-12 in dendritic cells and macrophages, implying the existence of stringent regulatory mechanisms. In this study, we sought to uncover the mechanisms underlying TLR-induced IL-12 expression and the Th1 response. By systemic screening, we identified a number of protein kinases involved in the regulation of TLRinduced IL-12 expression. In particular, PI3 K, ERK, and m TOR play critical roles in the TLR-induced Th1 response by regulating IL-12 and IL-10 production in innate immune cells. Moreover, we identified c-fos as a key molecule that mediates m TOR-regulated IL-12 and IL-10 expression in TLR signaling. Mechanistically, m TOR plays a crucial role in c-fos expression, thereby modulating NFκB binding to promoters of IL-12 and IL-10. By controlling the expression of a special innate gene program, m TOR can specifically regulate the TLR-induced T cell response in vivo. Furthermore, blockade of m TOR by rapamycin efficiently boosted TLR-induced antigen-specific T and B cell responses to HBV and HCV vaccines. Taken together, these results reveal a novel mechanism through which m TOR regulates TLR-induced IL-12 and IL-10 production, contributing new insights for strategies to improve vaccine efficacy.
基金financially supported by the National Natural Science Foundation of China (Grant 81202381)the National Basic Research Program of China (973 Program) (Grant 2012CB518904)
文摘Enterovirus 71(EV71) infection causes severe central nervous system damage, particularly for children under the age of 5 years old, which remains a major public health burden worldwide. Clinical data released that children may be repeatedly infected by different members in enterovirus and get even worsen. Mucosa, especially epithelium of alimentary canal, was considered the primary site of EV71 infection. It has been elusive whether the preexsiting viral antibody in mucosa plays a role in EV71 infection. To answer this question, we respectively measured viral antibody response and EV71 RNA copy number of one hundred throat swab specimens from clinically confirmed EV71-infected children. The results released that low-level of mucosal Ig G antibody against EV71 broadly existed in young population. More importantly, it further elucidated that the children with mucosal preexsiting EV71 Ig G were prone to be infected, which suggested a former viral Ig G mediated enhancement of viral infection in vivo.
基金supported by the National Key Research and Development Program,Ministry of Science and Technology of China(2007BAI28B04)the National Science and Technology Major Project on Major Infectious Diseases(2012ZX10001-008,2008ZX10001-010)
文摘Dental caries remains one of the most common global chronic diseases caused by Streptococcus mutans,which is prevalent all over the world.The caries prevalence of children aged between 5-6 years old in China is still in very high rate.A potent and effective anti-caries vaccine has long been expected for caries prevention but no vaccines have been brought to market till now mainly due to the low ability to induce and maintain protective antibody in oral fluids.This review will give a brief historical retrospect on study of dental caries and pathogenesis,effective targets for anti-caries vaccines,oral immune system and immunization against dental caries.Then,salivary IgA antibodies and the protective responses are discussed in the context of the ontogeny of mucosal immunity to indigenous oral streptococcal.The methods and advancement for induction of specific anticaries salivary sIgA antibodies and enhancement of specific anti-caries salivary sIgA antibodies by intranasal immunization with a safe effective mucosal adjuvant are described.The progress in the enhancement of salivary sIgA antibodies and anticaries protection by intranasal immunization with flagellin-PAc fusion protein will be highlighted.Finally,some of the main strategies that have been used for successful mucosal vaccination of caries vaccine are reviewed,followed by discussion of the mucosal adjuvant choice for achieving protective immunity at oral mucosal membranes for development of a nasal-spray or nasal-drop anti-caries vaccine for human.
基金This work was financially supported by the National S＆T Major Project on Major Infectious Diseases （Grant 2012ZX10001-008 and 2008ZX10001-010）, the National Basic Research Program of China （973 Program） （Grant 2012CB518904） from the Ministry of Science and Technology of the People＇s Republic of China, and the National Natural Science Foundation of China （Grant 81202381）. We sincerely thank Dr George Dacai Liu for his critical comments and revision of the article. We are thankful to the Core Facility and Technical Support, Wuhan Institute of Virology and Xuefang An for valuable assistance in the animal studies, as well as Ying Sun, Rong Bao and Benxia He for their help with the sample collection.
文摘Flagellin is a potent activator of a broad range of cell types that are involved in innate and adaptive immunity. Therefore, it is a good adjuvant candidate for vaccines, and it might function as a biological protectant against both major acute radiation syndrome during cancer radiotherapy and a mitigator of radiation emergencies. However, accumulating evidence has implicated flagellin in the occurrence of some inflammatory diseases, such as acute lung inflammation, cardiovascular collapse and inflammatory bowel disease. The aim of this study was to elucidate whether only flagellin-TLR5 signaling activation plays a role in the pathophysiology of liver or whether some other flagellin activity also contributes to liver injury either via bacterial infections or during clinical applications. Recombinant flagellin proteins with or without TLR5-stimulating activity were used to evaluate the role of flagellin-TLR5 signaling in liver injury in wild-type and TLR5 KO mice. Gross lesions and large areas of hepatocellular necrosis were observed in liver tissue 12 h after the intraperitoneal administration of 100 or 200 pg flagellin （FliC） in a dose-and time-dependent manner in wild-type mice, but not in TLR5 KO mice. Deletion of the N-terminal or TLR5 binding domain of flagellin inhibited flagellin-induced inflammatory responses and the subsequent acute liver function abnormality and damage. These data confirmed that flagellin is an essential determinant of liver injury and demonstrated that the over-activation of TLR5 signaling by high-dose flagellin caused acute inflammatory responses, neutrophil accumulation and oxidative stress in the liver, which contributes to the progression and severity of flagellin-induced liver injury.
基金This work was financially supported by the National Natural Science Foundation of China （Grant numbers 81202381 and 81202312）, the National Basic Research Program of China （973 Program） （Grant number 2012CB518904）, the National S＆T Major Project on Major Infectious Diseases （Grant numbers 2012ZX10001-008 and 2008ZX10001-010） from the Ministry of Science and Technology of the People＇s Republic of China. We sincerely thank the Core Facility and Technical Support, Wuhan Institute of Virology and Xuefang An for valuable assistance in the animal studies and Ying Sun, Rong Bao, and Benxia He for their help with the sample collection.
文摘Bacterial flagellin is a unique pathogen-associated molecular pattern （PAMP）, which can be recognized by surface localized Toll-like receptor 5 （TLR5） and the cytosolic NOD-like receptor （NLR） protein 4 （NLRC4） receptors. Activation of the TLR5 and/or NLRC4 signaling pathways by flagellin and the resulting immune responses play important roles in anti-bacterial immunity. However, it remains unclear how the dual activities of flagellin that activate the TLR5 and/or NLRC4 signaling pathways orchestrate the immune responses. In this study, we assessed the effects of flagellin and its mutants lacking the ability to activate TLR5 and NLRC4 alone or in combination on the adaptive immune responses against flagellin. Flagellin that was unable to activate NLRC4 induced a significantly higher antibody response than did wild-type flagellin. The increased antibody response could be eliminated when macrophages were depleted in vivo. The activation of NLRC4 by flagellin downregulated the flagellin-induced and TLR5-mediated immune responses against flagellin.
基金grants from the National Natural Science Foundation of China(Nos.31300717 and 81461130019)the Grants of Deutsche Forschungsgemeinschaft(TRR60 and GK1949).
文摘The innate immune system plays an essential role in the host defense against infections by initially sensing and recognizing diverse microbial pathogens and directing adaptive immune responses to their infections.How does the innate immune system sense and recognize pathogens?The identification of pattern recognition receptors(PRRs)during the past decades has brought us into a new era to explore this fundamental question.PRRs are an array of germline-encoded multifunctional proteins that do not recognize specific pathogens but rather recognize conserved molecular patterns associated with various classes of pathogens,leading to pathogen-associated molecular patterns(PAMPs).
文摘Mammals peacefully co-exist with vast numbers of different bacteria most of the time.Whether pathogenic,nonpathogenic or commensal to a mammalian host,bacteria produce microbeassociated molecular patterns(MAMPs)or pathogen-associated molecular patterns(PAMPs)that are recognized by multiple classes of germline-encoded pattern-recognition receptors(PRRs).Flagellin,a major structural protein of bacterial flagella,is composed of four domains(D0,D1,D2 and D3),of which the D0 and D1 domains are the most highly conserved.
基金supported by grants from Deutsche Forschungsgemeinschaft(TRR60 and GK1949)the National Science Foundation of China(No.81771688 and 81461130019).
文摘The Toll-like receptor(TLR)signaling pathway,which is composed of a group of highly conserved molecules,plays a critical role in the recognition of pathogen-associated molecular patterns(PAMPs).Innate immunity activated through the TLR signaling pathway serves as a first defense against infectious diseases.1 However,the exact function of TLR signaling in viral infections remains to be elucidated.
