In pig-to-human xenotransplantation,the transmission risk of porcine endogenous retroviruses(PERVs)is of great concern.However,the distribution of PERVs in pig genomes,their genetic variation among Eurasian pigs,and t...In pig-to-human xenotransplantation,the transmission risk of porcine endogenous retroviruses(PERVs)is of great concern.However,the distribution of PERVs in pig genomes,their genetic variation among Eurasian pigs,and their evolutionary history remain unclear.We scanned PERVs in the current pig reference genome(assembly Build 11.1),and identified 36 long complete or near-complete PERVs(lc PERVs)and 23 short incomplete PERVs(si PERVs).Besides three known PERVs(PERV-A,-B,and-C),four novel types(PERV-JX1,-JX2,-JX3,and-JX4)were detected in this study.According to evolutionary analyses,the newly discovered PERVs were more ancient,and PERV-Bs probably experienced a bottleneck~0.5 million years ago(Ma).By analyzing63 high-quality porcine whole-genome resequencing data,we found that the PERV copy numbers in Chinese pigs were lower(32.0±4.0)than in Western pigs(49.1±6.5).Additionally,the PERV sequence diversity was lower in Chinese pigs than in Western pigs.Regarding the lc PERV copy numbers,PERV-A and-JX2 in Western pigs were higher than in Chinese pigs.Notably,Bama Xiang(BMX)pigs had the lowest PERV copy number(27.8±5.1),and a BMX individual had no PERV-C and the lowest PERV copy number(23),suggesting that BMX pigs were more suitable for screening and/or modification as xenograft donors.Furthermore,we identified 451 PERV transposon insertion polymorphisms(TIPs),of which 86 were shared by all 10 Chinese and Western pig breeds.Our findings provide systematic insights into the genomic distribution,variation,evolution,and possible biological function of PERVs.展开更多
目的明确PERV的整合是否影响HEK293细胞中HERV-W各基因表达水平。方法根据GenBank中登录的基因序列,分别设计HERV-W gag、HERV-W pol、HERV-Wenv、syncytin-1和humanβ-actin引物,并分别建立SYBR Green Ⅰ荧光定量PCR检测方法,用于检测H...目的明确PERV的整合是否影响HEK293细胞中HERV-W各基因表达水平。方法根据GenBank中登录的基因序列,分别设计HERV-W gag、HERV-W pol、HERV-Wenv、syncytin-1和humanβ-actin引物,并分别建立SYBR Green Ⅰ荧光定量PCR检测方法,用于检测HEK293、HEK293-PERV中各基因mRNA的表达。结果本研究建立的检测方法均具有良好的特异性、敏感性和稳定性,标准曲线的相关系数大于0.99,扩增效率介于95%~110%,可用于检测。结论检测结果经2^(-△△Ct)分析后,发现与对照相比,PERV整合后的HEK293-PERV中HERV-Wgag、HERV-Wpol、HERV-Wenv和syncytin-1 mRNA相对表达量分别升高37.08倍、42.56倍、2.49倍和13.17倍,为进一步明确PERV在异种移植中的安全性提供参考。展开更多
AIM： To establish a method detecting porcine endogenous retrovirus （PERV） in China experimental minipigs and to evaluate the safety of PERV in three individuals treated with bioartificial liver support systems base...AIM： To establish a method detecting porcine endogenous retrovirus （PERV） in China experimental minipigs and to evaluate the safety of PERV in three individuals treated with bioartificial liver support systems based on porcine hepatocytes. METHODS： Porcine hepatocytes were isolated with two-stage perfusion method, then cultured in the bioreactor, which is separated by a semipermeable membrane （0.2μm） from the lumen through which the patients＇ blood plasma was circulated. After posthemoperfusion, patients＇ blood was obtained for screening. Additionally, samples of medium collected from both intraluminal and extraluminal compartments of the laboratory bioreactor and culture supernate in vitro was analyzed. The presence of viral sequences was estimated by polymerase chain reaction （PCR） and reverse transcriptase-polymerase chain reaction （RTPCR）. Finally, the infection of virus in the supernate of common culture was ascertained by exposure to the fetal liver cells. RESULTS： PERV-specific gag sequences were found in the porcine hepatocytes using RT-PCR. and were detected in all samples from the intraluminal, extraluminal samples and culture supernate. However, culture supernatant from primary porcine hepatocytes （cleared of cellular debris） failed to infect human fetal liver cells. Finally, RT-PCR detected no PERV infection was found in the blood samples obtained from three patients at various times post-hemoperfusion. CONCLUSION： The assays used are specific and sensitive, identified by second PCR. PERVs could be released from hepatocytes cultured in bioreactor without the stimulation of mitogen and could not be prevented by the hollow fiber semipermeable membrane, indicating the existence of PERV safety in extracorporeal bioartificial liver support system （EBLSS）.展开更多
基金supported by the National Swine Industry and Technology System of China(nycytx-009)National Natural Science Foundation of China(31672383)。
文摘In pig-to-human xenotransplantation,the transmission risk of porcine endogenous retroviruses(PERVs)is of great concern.However,the distribution of PERVs in pig genomes,their genetic variation among Eurasian pigs,and their evolutionary history remain unclear.We scanned PERVs in the current pig reference genome(assembly Build 11.1),and identified 36 long complete or near-complete PERVs(lc PERVs)and 23 short incomplete PERVs(si PERVs).Besides three known PERVs(PERV-A,-B,and-C),four novel types(PERV-JX1,-JX2,-JX3,and-JX4)were detected in this study.According to evolutionary analyses,the newly discovered PERVs were more ancient,and PERV-Bs probably experienced a bottleneck~0.5 million years ago(Ma).By analyzing63 high-quality porcine whole-genome resequencing data,we found that the PERV copy numbers in Chinese pigs were lower(32.0±4.0)than in Western pigs(49.1±6.5).Additionally,the PERV sequence diversity was lower in Chinese pigs than in Western pigs.Regarding the lc PERV copy numbers,PERV-A and-JX2 in Western pigs were higher than in Chinese pigs.Notably,Bama Xiang(BMX)pigs had the lowest PERV copy number(27.8±5.1),and a BMX individual had no PERV-C and the lowest PERV copy number(23),suggesting that BMX pigs were more suitable for screening and/or modification as xenograft donors.Furthermore,we identified 451 PERV transposon insertion polymorphisms(TIPs),of which 86 were shared by all 10 Chinese and Western pig breeds.Our findings provide systematic insights into the genomic distribution,variation,evolution,and possible biological function of PERVs.
基金Supported by the Natural Scientific Foundation of China No.30027001
文摘AIM： To establish a method detecting porcine endogenous retrovirus （PERV） in China experimental minipigs and to evaluate the safety of PERV in three individuals treated with bioartificial liver support systems based on porcine hepatocytes. METHODS： Porcine hepatocytes were isolated with two-stage perfusion method, then cultured in the bioreactor, which is separated by a semipermeable membrane （0.2μm） from the lumen through which the patients＇ blood plasma was circulated. After posthemoperfusion, patients＇ blood was obtained for screening. Additionally, samples of medium collected from both intraluminal and extraluminal compartments of the laboratory bioreactor and culture supernate in vitro was analyzed. The presence of viral sequences was estimated by polymerase chain reaction （PCR） and reverse transcriptase-polymerase chain reaction （RTPCR）. Finally, the infection of virus in the supernate of common culture was ascertained by exposure to the fetal liver cells. RESULTS： PERV-specific gag sequences were found in the porcine hepatocytes using RT-PCR. and were detected in all samples from the intraluminal, extraluminal samples and culture supernate. However, culture supernatant from primary porcine hepatocytes （cleared of cellular debris） failed to infect human fetal liver cells. Finally, RT-PCR detected no PERV infection was found in the blood samples obtained from three patients at various times post-hemoperfusion. CONCLUSION： The assays used are specific and sensitive, identified by second PCR. PERVs could be released from hepatocytes cultured in bioreactor without the stimulation of mitogen and could not be prevented by the hollow fiber semipermeable membrane, indicating the existence of PERV safety in extracorporeal bioartificial liver support system （EBLSS）.
