The Hantaan virus(HTNV)and Seoul virus(SEOV)mutants have accumulated over time.It is important to determine whether their neutralizing epitopes have evolved,thereby making the current vaccine powerless.However,it is i...The Hantaan virus(HTNV)and Seoul virus(SEOV)mutants have accumulated over time.It is important to determine whether their neutralizing epitopes have evolved,thereby making the current vaccine powerless.However,it is impossible to determine by using traditional plaque reduction neutralization test(PRNT),because it requires large numbers of live mutant strains.Pseudovirus-based neutralization assays(PBNA)were developed by employing vesicular stomatitis virus(VSV)backbone incorporated with HTNV or SEOV glycoproteins(VSVDG*-HTNVG or VSVDG*-SEOVG).56 and 51 single amino acid substitutions of glycoprotein(GP)in HTNV and SEOV were selected and introduced into the reference plasmid.Then the mutant pseudoviruses were generated and tested by PBNA.The PBNA results were highly correlated with PRNT ones with R2 being 0.91 for VSVDG*-HTNVG and 0.82 for VSVDG*-SEOVG.53 HTNV mutant pseudoviruses and 46 SEOV mutants were successfully generated.Importantly,by using PBNA,we found that HTNV or SEOV immunized antisera could neutralize all the corresponding 53 HTNV mutants or the 46 SEOV mutants respectively.The novel PBNA enables us to closely monitor the effectiveness of vaccines against large numbers of evolving HTNV and SEOV.And the current vaccine remains to be effective for the naturally occurring mutants.展开更多
Seoul virus(SEOV), which is predominantly carried by Rattus norvegicus, is one of the major causes of hemorrhagic fever with renal syndrome(HFRS) in China. Hubei province, located in the central south of China, has ex...Seoul virus(SEOV), which is predominantly carried by Rattus norvegicus, is one of the major causes of hemorrhagic fever with renal syndrome(HFRS) in China. Hubei province, located in the central south of China, has experienced some of the most severe epidemics of HFRS. To investigate the mitochondrial DNA(mt DNA)-based phylogenetics of wild rats in Hubei, and the relationship with SEOV infection, 664 wild rats were captured from five trapping sites in Hubei from2000–2009 and 2014–2015. Using reverse-transcription(RT)-PCR, 41(6.17%) rats were found to be positive for SEOV infection. The SEOV-positive percentage in Yichang was significantly lower than that in other areas. The mt DNA D-loop and cytochrome b(cyt-b) genes of 103 rats were sequenced.Among these animals, 37 were SEOV-positive. The reconstruction of the phylogenetic relationship(based on the complete D-loop and cyt-b sequences) allowed the rats to be categorized into two lineages, R. norvegicus and Rattus nitidus, with the former including the majority of the rats. For both the D-loop and cyt-b genes, 18 haplotypes were identified. The geographic distributions of the different haplotypes were significantly different. There were no significant differences in the SEOVpositive percentages between different haplotypes. There were three sub-lineages for the D-loop,and two for cyt-b. The SEOV-positive percentages for each of the sub-lineages did not significantly differ. This indicates that the SEOV-positive percentage is not related to the mt DNA D-loop or cyt-b haplotype or the sub-lineage of rats from Hubei.展开更多
基金supported by the National Science and Technology Major Projects of Drug Discovery[Grant Number 2018ZX09101-001]
文摘The Hantaan virus(HTNV)and Seoul virus(SEOV)mutants have accumulated over time.It is important to determine whether their neutralizing epitopes have evolved,thereby making the current vaccine powerless.However,it is impossible to determine by using traditional plaque reduction neutralization test(PRNT),because it requires large numbers of live mutant strains.Pseudovirus-based neutralization assays(PBNA)were developed by employing vesicular stomatitis virus(VSV)backbone incorporated with HTNV or SEOV glycoproteins(VSVDG*-HTNVG or VSVDG*-SEOVG).56 and 51 single amino acid substitutions of glycoprotein(GP)in HTNV and SEOV were selected and introduced into the reference plasmid.Then the mutant pseudoviruses were generated and tested by PBNA.The PBNA results were highly correlated with PRNT ones with R2 being 0.91 for VSVDG*-HTNVG and 0.82 for VSVDG*-SEOVG.53 HTNV mutant pseudoviruses and 46 SEOV mutants were successfully generated.Importantly,by using PBNA,we found that HTNV or SEOV immunized antisera could neutralize all the corresponding 53 HTNV mutants or the 46 SEOV mutants respectively.The novel PBNA enables us to closely monitor the effectiveness of vaccines against large numbers of evolving HTNV and SEOV.And the current vaccine remains to be effective for the naturally occurring mutants.
基金supported by grants from the National Natural Science Foundation of China(81402728,81371865)
文摘Seoul virus(SEOV), which is predominantly carried by Rattus norvegicus, is one of the major causes of hemorrhagic fever with renal syndrome(HFRS) in China. Hubei province, located in the central south of China, has experienced some of the most severe epidemics of HFRS. To investigate the mitochondrial DNA(mt DNA)-based phylogenetics of wild rats in Hubei, and the relationship with SEOV infection, 664 wild rats were captured from five trapping sites in Hubei from2000–2009 and 2014–2015. Using reverse-transcription(RT)-PCR, 41(6.17%) rats were found to be positive for SEOV infection. The SEOV-positive percentage in Yichang was significantly lower than that in other areas. The mt DNA D-loop and cytochrome b(cyt-b) genes of 103 rats were sequenced.Among these animals, 37 were SEOV-positive. The reconstruction of the phylogenetic relationship(based on the complete D-loop and cyt-b sequences) allowed the rats to be categorized into two lineages, R. norvegicus and Rattus nitidus, with the former including the majority of the rats. For both the D-loop and cyt-b genes, 18 haplotypes were identified. The geographic distributions of the different haplotypes were significantly different. There were no significant differences in the SEOVpositive percentages between different haplotypes. There were three sub-lineages for the D-loop,and two for cyt-b. The SEOV-positive percentages for each of the sub-lineages did not significantly differ. This indicates that the SEOV-positive percentage is not related to the mt DNA D-loop or cyt-b haplotype or the sub-lineage of rats from Hubei.
