JE Nakayama/JE SA14-14-2 virus structural region intertypic viruses: biological properties in the mouse model of neuroinvasive disease.
A molecular clone of Japanese encephalitis (JE) virus Nakayama strain was used to create intertypic viruses containing either the 5'-C-prM-E or the prM-E region of the attenuated JE SA14-14-2 virus in the JE Nakayama background. These two intertypic JE viruses, JE-X/5'CprME(S) and JE-X/prME(S), respectively, generally resembled the parental JE virus in cell culture properties. Similar to virus derived from the JE Nakayama molecular clone (JE-XJN), JE-X/prME(S) was highly neuroinvasive and neurovirulent for young adult mice, whereas JE-X/5'CprME(S) was attenuated for neuroinvasiveness and only partially attenuated for neurovirulence. Immunization of young mice with JE-X/5'CprME(S) virus elicited neutralizing antibodies against JE Nakayama virus and conferred protection against encephalitis following challenge with JE Nakayama virus. The sequence of the JE-X/5'CprME(S) virus differed from that of JE-X/prME(S) virus at two nucleotides in the 5' UTR, 3 amino acid positions in the capsid protein, 4 positions in the prM protein and 1 in the envelope protein. For JE-X/prME(S) virus, the 4 differences in prM and the single substitution in the envelope represented reversions to the sequence of JE Nakayama virus. Overall, this study reveals that molecular determinants associated with the prM-E region of the attenuated JE SA14-14-2 virus are insufficient by themselves to confer an attenuation phenotype upon JE Nakayama virus. This suggests a role for determinants in the 5' UTR and/or the capsid protein of the JE SA 14-14-2 virus genome in influencing the virulence properties of the JE Nakayama virus in the mouse model.
Chambers
Thomas J
TJ
Department of Molecular Microbiology and Immunology, St. Louis University School of Medicine, 1402 South Grand Ave. St. Louis, MO 63104, USA. thomas_chambers2@merck.com
Droll
Deborah A
DA
Jiang
Xiaoshan
X
Wold
William S M
WS
Nickells
Janice A
JA
D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D004279:DNA, Viral / Q000235:genetics; D004195:Disease Models, Animal; D004664:Encephalitis Virus, Japanese / Q000145:classification / Q000235:genetics* / Q000472:pathogenicity; D004672:Encephalitis, Japanese / Q000503:physiopathology; D016679:Genome, Viral; D051379:Mice; D009422:Nervous System Diseases / Q000473:pathology / Q000821:virology*; D009474:Neurons / Q000473:pathology / Q000821:virology; D014774:Virulence
D004279:DNA, Viral