To compare the helper activities of different avian viruses for propagation of recombinant avian adeno-associated virus(rAAAV),AAV-293 cells were cotransfected with the AAAV vector pAITR-GFP containing green fluoresce...To compare the helper activities of different avian viruses for propagation of recombinant avian adeno-associated virus(rAAAV),AAV-293 cells were cotransfected with the AAAV vector pAITR-GFP containing green fluorescent protein(GFP)gene,the AAAV helper vector pcDNA-ARC expressing the rep and cap genes,and the adenovirus helper vector pHelper expressing Ad5 E2A,E4,and VA-RNA genes.Chicken embryonic fibroblast(CEF)or chicken embryonic liver(CEL)cells were cotransfected with the AAAV vector and the AAAV helper vector,followed by infection with Marek's disease virus(MDV),avian adenovirus,chicken embryo lethal orphan(CELO)virus or infectious bursal disease virus(IBDV).Infectious rAAAV particles generated by the two strategies were harvested and titrated on CEF and CEL cells.A significantly higher viral titer was obtained with the helper activity provided by the pHelper vector than by MDV or CELO virus.Further experiments showed that rAAAV-mediated green fluorescent protein(gfp)expression was overtly enhanced by MDV or CELO virus super infection or treatment with sodium butyric acid,but not by IBDV super infection.These data demonstrated that MDV and CELO viruses could provide weak helper activity for propagation of rAAAV,and rAAAV-mediated transgene expression could be enhanced by super infection with the helper viruses.展开更多
Between 2021 and 2023,approximately 400 pediatric cases of acute hepatitis of unknown etiology(AHUE)were reported in European countries and the United States.In 2023,three pediatric studies revealed that adeno-associa...Between 2021 and 2023,approximately 400 pediatric cases of acute hepatitis of unknown etiology(AHUE)were reported in European countries and the United States.In 2023,three pediatric studies revealed that adeno-associated virus serotype 2(AAV-2)infection was associated with AHUE.This article presents a summary and comparison of the results of metagenomic sequencing,viral wholegenome sequencing,virus-specific real-time polymerase chain reaction(PCR)and histological analysis of the liver,all of which were among the common investigative methods used in the three pediatric studies.All three pediatric studies revealed 80%or greater rates of positivity for AAV-2 in cases of AHUE according to metagenomic sequencing.Moreover,on the basis of PCR results,two studies revealed high AAV-2 positivity rates(96.4%and 81.2%)among cases of AHUE.These findings suggest that AAV-2 is a pathogen in AHUE.Coinfection with AAV-2 and one or more helper viruses(human adenovirus,human herpesvirus 6B,Epstein–Barr virus,etc.),high viral loads of AAV-2 in blood,anti-AAV-2 IgM and human leukocyte antigen typing could be candidate diagnostic criteria for AHUE.AAV-2 infection should be incorporated into clinical guidelines for the management of acute liver failure.Cidofovir can be administered if coinfection with AAV-2 and HAdV is detected.展开更多
Hepatitis C virus(HCV)infection affects about 170 million people worldwide and it is a major cause of liver cirrhosis and hepatocellular carcinoma.HCV is a hepatotropic non-cytopathic virus able to persist in a great ...Hepatitis C virus(HCV)infection affects about 170 million people worldwide and it is a major cause of liver cirrhosis and hepatocellular carcinoma.HCV is a hepatotropic non-cytopathic virus able to persist in a great percentage of infected hosts due to its ability to escape from the immune control.Liver damage and disease progression during HCV infection are driven by both viral and host factors.Specifically,adaptive immune response carries out an essential task in controllingnon-cytopathic viruses because of its ability to recognize infected cells and to destroy them by cytopathic mechanisms and to eliminate the virus by non-cytolytic machinery.HCV is able to impair this response by several means such as developing escape mutations in neutralizing antibodies and in T cell receptor viral epitope recognition sites and inducing HCV-specific cytotoxic T cell anergy and deletion.To impair HCV-specific T cell reactivity,HCV affects effector T cell regulation by modulating T helper and Treg response and by impairing the balance between positive and negative co-stimulatory molecules and between pro-and antiapoptotic proteins.In this review,the role of adaptive immune response in controlling HCV infection and the HCV mechanisms to evade this response are reviewed.展开更多
基金the National Natural Science Foundation of China(30571373)
文摘To compare the helper activities of different avian viruses for propagation of recombinant avian adeno-associated virus(rAAAV),AAV-293 cells were cotransfected with the AAAV vector pAITR-GFP containing green fluorescent protein(GFP)gene,the AAAV helper vector pcDNA-ARC expressing the rep and cap genes,and the adenovirus helper vector pHelper expressing Ad5 E2A,E4,and VA-RNA genes.Chicken embryonic fibroblast(CEF)or chicken embryonic liver(CEL)cells were cotransfected with the AAAV vector and the AAAV helper vector,followed by infection with Marek's disease virus(MDV),avian adenovirus,chicken embryo lethal orphan(CELO)virus or infectious bursal disease virus(IBDV).Infectious rAAAV particles generated by the two strategies were harvested and titrated on CEF and CEL cells.A significantly higher viral titer was obtained with the helper activity provided by the pHelper vector than by MDV or CELO virus.Further experiments showed that rAAAV-mediated green fluorescent protein(gfp)expression was overtly enhanced by MDV or CELO virus super infection or treatment with sodium butyric acid,but not by IBDV super infection.These data demonstrated that MDV and CELO viruses could provide weak helper activity for propagation of rAAAV,and rAAAV-mediated transgene expression could be enhanced by super infection with the helper viruses.
文摘Between 2021 and 2023,approximately 400 pediatric cases of acute hepatitis of unknown etiology(AHUE)were reported in European countries and the United States.In 2023,three pediatric studies revealed that adeno-associated virus serotype 2(AAV-2)infection was associated with AHUE.This article presents a summary and comparison of the results of metagenomic sequencing,viral wholegenome sequencing,virus-specific real-time polymerase chain reaction(PCR)and histological analysis of the liver,all of which were among the common investigative methods used in the three pediatric studies.All three pediatric studies revealed 80%or greater rates of positivity for AAV-2 in cases of AHUE according to metagenomic sequencing.Moreover,on the basis of PCR results,two studies revealed high AAV-2 positivity rates(96.4%and 81.2%)among cases of AHUE.These findings suggest that AAV-2 is a pathogen in AHUE.Coinfection with AAV-2 and one or more helper viruses(human adenovirus,human herpesvirus 6B,Epstein–Barr virus,etc.),high viral loads of AAV-2 in blood,anti-AAV-2 IgM and human leukocyte antigen typing could be candidate diagnostic criteria for AHUE.AAV-2 infection should be incorporated into clinical guidelines for the management of acute liver failure.Cidofovir can be administered if coinfection with AAV-2 and HAdV is detected.
基金Grants from"Instituto de Salud Carlos Ⅲ",Spain and"European Regional Development Fund(ERDF),a way of making Europe",E.U.,No.PI12/00130"Fundacion de In-vestigacion Medica Mutua Madrilena",Spain,No.8922/2011Lokhande MU was funded by a research grant from"Asoci-acion de Hepatologia Translacional"No.AHT-2010/01,Spain
文摘Hepatitis C virus(HCV)infection affects about 170 million people worldwide and it is a major cause of liver cirrhosis and hepatocellular carcinoma.HCV is a hepatotropic non-cytopathic virus able to persist in a great percentage of infected hosts due to its ability to escape from the immune control.Liver damage and disease progression during HCV infection are driven by both viral and host factors.Specifically,adaptive immune response carries out an essential task in controllingnon-cytopathic viruses because of its ability to recognize infected cells and to destroy them by cytopathic mechanisms and to eliminate the virus by non-cytolytic machinery.HCV is able to impair this response by several means such as developing escape mutations in neutralizing antibodies and in T cell receptor viral epitope recognition sites and inducing HCV-specific cytotoxic T cell anergy and deletion.To impair HCV-specific T cell reactivity,HCV affects effector T cell regulation by modulating T helper and Treg response and by impairing the balance between positive and negative co-stimulatory molecules and between pro-and antiapoptotic proteins.In this review,the role of adaptive immune response in controlling HCV infection and the HCV mechanisms to evade this response are reviewed.
