Molecular analysis of dengue virus attenuation after serial passage in primary dog kidney cells.
The complete nucleotide sequences of the genomes of dengue-1 virus virulent 45AZ5 PDK-O and attenuated vaccine candidate strain 45AZ5 PDK-27 have been determined and compared with the dengue-1 virus Western Pacific (West Pac) 74 parent strain from which 45AZ5 PDK-O was derived. Twenty-five (0.23%) nucleotide and 10 (0.29%) amino acid substitutions occurred between parent strain dengue-1 virus West Pac 74 and virulent strain 45AZ5 PDK-O, which was derived from the parent by serial passage in diploid foetal rhesus lung (FRhL-2) and mutagenized with 5-azacytidine. These substitutions were preserved in the 45AZ5 PDK-27 vaccine. 45AZ5 PDK-O and PDK-27 strains, which differ by 27 passages in primary dog kidney (PDK) cells, show 25 (0.23%) nucleotide and 11 (0.32%) amino acid divergences. These comparative studies suggest that the changes which occurred between the West Pac 74 and 45AZ5 PDK-O strains may alter the biological properties of the virus but may not be important for attenuation. Important nucleotide base changes responsible for attenuation accumulated between 45AZ5 PDK-O and 27.
Puri
B
B
Infectious Diseases Department, Naval Medical Research Institute, Bethesda, Maryland 20889-5607, USA. PURI@MAIL2.NMRI.NNMC.NAVY.MIL
Nelson
W M
WM
Henchal
E A
EA
Hoke
C H
CH
Eckels
K H
KH
Dubois
D R
DR
Porter
K R
KR
Hayes
C G
CG
D000818:Animals; D002478:Cells, Cultured; D003716:Dengue Virus / Q000235:genetics* / Q000472:pathogenicity*; D004285:Dogs; D014644:Genetic Variation / Q000235:genetics; D016679:Genome, Viral; D006801:Humans; D007668:Kidney / Q000166:cytology; D008969:Molecular Sequence Data; D012367:RNA, Viral / Q000235:genetics; D017422:Sequence Analysis, DNA; D017423:Sequence Analysis, RNA; D012692:Serial Passage; D014613:Vaccines, Attenuated / Q000235:genetics; D014765:Viral Vaccines / Q000235:genetics*; D014774:Virulence
D012367:RNA, Viral; D014613:Vaccines, Attenuated; D014765:Viral Vaccines