BACKGROUND： A novel hybrid bioartificial liver（HBAL） was constructed using an anionic resin adsorption column and a multi-layer flat-plate bioreactor containing porcine hepatocytes co-cultured with bone marrow mese...BACKGROUND： A novel hybrid bioartificial liver（HBAL） was constructed using an anionic resin adsorption column and a multi-layer flat-plate bioreactor containing porcine hepatocytes co-cultured with bone marrow mesenchymal stem cells（MSCs）. This study aimed to evaluate the microbiological safety of the HBAL by detecting the transmission of porcine endogenous retroviruses（PERVs） into canines with acute liver failure（ALF） undergoing HBAL.METHODS： Eight dogs with ALF received a 6-hour HBAL treatment on the first day after the modeling by D-galactosamine administration. The plasma in the HBAL and the whole blood in the dogs were collected for PERV detection at regular intervals until one year later when the dogs were sacrificed to retrieve the tissues of several organs for immunohistochemistry and Western blotting for the investigation of PERV capsid protein gag p30 in the tissue. Furthermore, HEK293 cells were incubated to determine the in vitro infectivity.RESULTS： PERV RNA and reverse transcriptase activity were observed in the plasma of circuit 3, suggesting that PERV particles released in circuit 3. No positive PERV RNA and reverse transcriptase activity were detected in other plasma. No HEK293 cells were infected by the plasma in vitro. In addition, all PERV-related analyses in peripheral blood mononuclear cells and tissues were negative.CONCLUSION： No transmission of PERVs into ALF canines suggested a reliable microbiological safety of HBAL based on porcine hepatocytes.展开更多
Donor cornea shortage is a primary hurdle in the development of corneal transplantation. Of all species, porcine corneas are the ideal transplantation material for humans. However, the xenoimmune rejection induced by ...Donor cornea shortage is a primary hurdle in the development of corneal transplantation. Of all species, porcine corneas are the ideal transplantation material for humans. However, the xenoimmune rejection induced by porcine corneal xenotransplantation compromises surgical efficacy. Although the binding of IgM/IgG in human serum to a genetically modified porcine cornea is significantly weaker than that of the wild type(WT), genetically modified porcine corneas do not display a prolonged graft survival time in vivo. Conversely, costimulatory blockade drugs, such as anti-CD40 antibodies, can reduce the xenoimmune response and prolong graft survival time in animal experiments. Moreover, porcine endothelial grafts can survive for more than 6mo with only the subconjunctival injection of a steroid-based immunosuppressants regime; therefore, they show great value for treating corneal endothelial disease. In addition, zoonotic transmission is a primary concern of xenotransplantation. Porcine endogenous retrovirus(PERV) is the most significant virus assessed by ophthalmologists. PERV integrates into the porcine genome and infects human cells in vitro. Fortunately, no evidence from in vivo studies has yet shown that PERV can be transmitted to hosts.展开更多
Porcine endogenous retroviruses(PERVs)are proviruses that have medical value in xenotransplantation.However,the evolutionary process leading to the generation of modern PERVs is not well understood.In this study,we in...Porcine endogenous retroviruses(PERVs)are proviruses that have medical value in xenotransplantation.However,the evolutionary process leading to the generation of modern PERVs is not well understood.In this study,we in silico mined 14 pig genomes and other available 304 mammalian genomes,which led to the documentation of 185 full-length PERVs or PERV-like sequences.Notably,we found that lesser Egyptian jerboa(Jaculus jaculus),rock hyrax(Procavia capensis)and eight Muridae species all harbored ancestral PERV-like sequences,indicative of ancient cross-species transmission events from none-porcine species to pigs.We also revealed that 11 genomic rearrangement events were mediated via PERVs,during the process of porcine evolution.In conclusion,these new findings help us to understand the complex evolution of the modern PERVs.展开更多
The provirus DNA sequence of porcine endogenous retrovirus (PERV) distributed in the pig genome is the major obstacle that restricts the swine as the organ donors in xenotransplantation, and the copy number of PERV va...The provirus DNA sequence of porcine endogenous retrovirus (PERV) distributed in the pig genome is the major obstacle that restricts the swine as the organ donors in xenotransplantation, and the copy number of PERV varies greatly among different breeds and individuals. In the experiment, 67 healthy, female Chinese Experimental Mini-Pigs (CEMPs) aged at 3—6 months were selected from the Animal Husbandry Station of China Agricultural University, the copy number of PERV and types of envelope protein gene (env) were then investigated by means of PCR analysis and Southern blotting. It is showed that the distribution of types of envelope protein gene in Landrace and CEMPs makes little difference, but the proportion of individuals carrying two types of envelope protein gene (env-A and env-B, which is de- noted as env-AB) is much larger than those which carry only one type of envelope protein gene (env-A or env-B). Meanwhile, two endogenous retrovirus free pigs were found for the first time during our research, and the copy number of others is relatively low, which is about 10 to 20. All the results illuminate the genetic diversity of indigenous pig breeds in China and the potential of CEMPs to serve as organ donors in xenotransplantation.展开更多
基金supported by grants from the National Natural Science Foundation of China(81300338)Postdoctoral Fellowship of Jiangsu province(1202057C)Project funding of Clinical Medical Center of Digestive Disease in Jiangsu province(BL2012001)
文摘BACKGROUND： A novel hybrid bioartificial liver（HBAL） was constructed using an anionic resin adsorption column and a multi-layer flat-plate bioreactor containing porcine hepatocytes co-cultured with bone marrow mesenchymal stem cells（MSCs）. This study aimed to evaluate the microbiological safety of the HBAL by detecting the transmission of porcine endogenous retroviruses（PERVs） into canines with acute liver failure（ALF） undergoing HBAL.METHODS： Eight dogs with ALF received a 6-hour HBAL treatment on the first day after the modeling by D-galactosamine administration. The plasma in the HBAL and the whole blood in the dogs were collected for PERV detection at regular intervals until one year later when the dogs were sacrificed to retrieve the tissues of several organs for immunohistochemistry and Western blotting for the investigation of PERV capsid protein gag p30 in the tissue. Furthermore, HEK293 cells were incubated to determine the in vitro infectivity.RESULTS： PERV RNA and reverse transcriptase activity were observed in the plasma of circuit 3, suggesting that PERV particles released in circuit 3. No positive PERV RNA and reverse transcriptase activity were detected in other plasma. No HEK293 cells were infected by the plasma in vitro. In addition, all PERV-related analyses in peripheral blood mononuclear cells and tissues were negative.CONCLUSION： No transmission of PERVs into ALF canines suggested a reliable microbiological safety of HBAL based on porcine hepatocytes.
基金Supported by National Natural Science Foundation of China(No.81470608)
文摘Donor cornea shortage is a primary hurdle in the development of corneal transplantation. Of all species, porcine corneas are the ideal transplantation material for humans. However, the xenoimmune rejection induced by porcine corneal xenotransplantation compromises surgical efficacy. Although the binding of IgM/IgG in human serum to a genetically modified porcine cornea is significantly weaker than that of the wild type(WT), genetically modified porcine corneas do not display a prolonged graft survival time in vivo. Conversely, costimulatory blockade drugs, such as anti-CD40 antibodies, can reduce the xenoimmune response and prolong graft survival time in animal experiments. Moreover, porcine endothelial grafts can survive for more than 6mo with only the subconjunctival injection of a steroid-based immunosuppressants regime; therefore, they show great value for treating corneal endothelial disease. In addition, zoonotic transmission is a primary concern of xenotransplantation. Porcine endogenous retrovirus(PERV) is the most significant virus assessed by ophthalmologists. PERV integrates into the porcine genome and infects human cells in vitro. Fortunately, no evidence from in vivo studies has yet shown that PERV can be transmitted to hosts.
基金supported by the Special Key Project of Biosafety Technologies(2017YFC1200800)for the National Major Research&Development Program of ChinaJ.C.is supported by National Natural Science Foundation of China under grant no.31671324 and CAS Pioneer Hundred Talents Program.
文摘Porcine endogenous retroviruses(PERVs)are proviruses that have medical value in xenotransplantation.However,the evolutionary process leading to the generation of modern PERVs is not well understood.In this study,we in silico mined 14 pig genomes and other available 304 mammalian genomes,which led to the documentation of 185 full-length PERVs or PERV-like sequences.Notably,we found that lesser Egyptian jerboa(Jaculus jaculus),rock hyrax(Procavia capensis)and eight Muridae species all harbored ancestral PERV-like sequences,indicative of ancient cross-species transmission events from none-porcine species to pigs.We also revealed that 11 genomic rearrangement events were mediated via PERVs,during the process of porcine evolution.In conclusion,these new findings help us to understand the complex evolution of the modern PERVs.
文摘The provirus DNA sequence of porcine endogenous retrovirus (PERV) distributed in the pig genome is the major obstacle that restricts the swine as the organ donors in xenotransplantation, and the copy number of PERV varies greatly among different breeds and individuals. In the experiment, 67 healthy, female Chinese Experimental Mini-Pigs (CEMPs) aged at 3—6 months were selected from the Animal Husbandry Station of China Agricultural University, the copy number of PERV and types of envelope protein gene (env) were then investigated by means of PCR analysis and Southern blotting. It is showed that the distribution of types of envelope protein gene in Landrace and CEMPs makes little difference, but the proportion of individuals carrying two types of envelope protein gene (env-A and env-B, which is de- noted as env-AB) is much larger than those which carry only one type of envelope protein gene (env-A or env-B). Meanwhile, two endogenous retrovirus free pigs were found for the first time during our research, and the copy number of others is relatively low, which is about 10 to 20. All the results illuminate the genetic diversity of indigenous pig breeds in China and the potential of CEMPs to serve as organ donors in xenotransplantation.
