کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
2409571 | 1103223 | 2006 | 10 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Molecular characterization of attenuated Japanese encephalitis live vaccine strain ML-17 Molecular characterization of attenuated Japanese encephalitis live vaccine strain ML-17](/preview/png/2409571.png)
The Japanese encephalitis (JE) zoonotic vaccine strain ML-17 was sequenced and compared to related JE virus strains to identify genomic attenuation markers. Relative to its parental strain, JaOH0566, 25 nucleotide alterations and 10 amino acid changes to, prM/M(2), NS2A(1), NS4B(3) and NS5(4) proteins were recorded. Both structural-gene changes were in the prM/M region (127Met → Ile and 274Asn → Thr). To study the effects of these prM/M changes, mutants bearing the changes were prepared using an infectious clone of JaOArS982 previously established at this lab. Compared with JaOArS982, mutant 127(Met → Ile) showed marked reduction in murine neuroinvasiveness. Mutant 274(Asn → Thr), showed slight reduction. Neither mutant recorded ML-17-equivalent attenuation, implying that prM/M changes need to combine with other recorded genomic differences to cause attenuation. Importantly, ML-17 with its unchanged E region, presents a possible backbone candidate for preparation of “E-replacement” type live attenuated flavivirus chimeric vaccines.
Journal: Vaccine - Volume 24, Issue 4, 23 January 2006, Pages 402–411