期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:2014
卷号:111
期号:36
页码:13169-13174
DOI:10.1073/pnas.1411290111
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:SignificanceHuman respiratory syncytial virus (RSV) is the most important viral agent of serious pediatric respiratory-tract disease. We designed new live attenuated RSV vaccine candidates by codon-pair deoptimization (CPD). Specifically, viral ORFs were recoded to increase the usage of underrepresented codon pairs, leaving amino acid coding unchanged. CPD viruses were temperature-sensitive and grew less efficiently in vitro than wild-type RSV. In addition, the CPD viruses exhibited a range of restriction in mice and African green monkeys that compared favorably with existing attenuated strains presently in clinical studies. This study produced examples of a new type of vaccine candidate for RSV and showed that CPD of a nonsegmented negative-strand RNA virus can rapidly generate vaccine candidates with a range of attenuation. Human respiratory syncytial virus (RSV) is the most important viral agent of serious pediatric respiratory-tract disease worldwide. A vaccine or generally effective antiviral drug is not yet available. We designed new live attenuated RSV vaccine candidates by codon-pair deoptimization (CPD). Specifically, viral ORFs were recoded by rearranging existing synonymous codons to increase the content of underrepresented codon pairs. Amino acid coding was completely unchanged. Four CPD RSV genomes were designed in which the indicated ORFs were recoded: Min A (NS1, NS2, N, P, M, and SH), Min B (G and F), Min L (L), and Min FLC (all ORFs except M2-1 and M2-2). Surprisingly, the recombinant CPD viruses were temperature-sensitive for replication in vitro (level of sensitivity: Min FLC > Min L > Min B > Min A). All of the CPD mutants grew less efficiently in vitro than recombinant wild-type (WT) RSV, even at the typically permissive temperature of 32 {degrees}C (growth efficiency: WT > Min L > Min A > Min FLC > Min B). CPD of the ORFs for the G and F surface glycoproteins provided the greatest restrictive effect. The CPD viruses exhibited a range of restriction in mice and African green monkeys comparable with that of two attenuated RSV strains presently in clinical trials. This study provided a new type of attenuated RSV and showed that CPD can rapidly generate vaccine candidates against nonsegmented negative-strand RNA viruses, a large and expanding group that includes numerous pathogens of humans and animals.
关键词:negative strand RNA virus ; pneumovirus ; live attenuated vaccine