Temperature-sensitive mutants of enterovirus 71 show attenuation in cynomolgus monkeys.
Enterovirus 71 (EV71) is one of the major causative agents of hand, foot and mouth disease and is sometimes associated with serious neurological disorders. In this study, an attempt was made to identify molecular determinants of EV71 attenuation of neurovirulence in a monkey infection model. An infectious cDNA clone of the virulent strain of EV71 prototype BrCr was constructed; temperature-sensitive (ts) mutations of an attenuated strain of EV71 or of poliovirus (PV) Sabin vaccine strains were then introduced into the infectious clone. In vitro and in vivo phenotypes of the parental and mutant viruses were analysed in cultured cells and in cynomolgus monkeys, respectively. Mutations in 3D polymerase (3D(pol)) and in the 3' non-translated region (NTR), corresponding to ts determinants of Sabin 1, conferred distinct temperature sensitivity to EV71. An EV71 mutant [EV71(S1-3')] carrying mutations in the 5' NTR, 3D(pol) and in the 3' NTR showed attenuated neurovirulence, resulting in limited spread of virus in the central nervous system of monkeys. These results indicate that EV71 and PV1 share common genetic determinants of neurovirulence in monkeys, despite the distinct properties in their original pathogenesis.
Arita
Minetaro
M
Department of Virology II, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashimurayama-shi, Tokyo 208-0011, Japan.
Shimizu
Hiroyuki
H
Department of Virology II, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashimurayama-shi, Tokyo 208-0011, Japan.
Nagata
Noriyo
N
Department of Pathology, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashimurayama-shi, Tokyo 208-0011, Japan.
Ami
Yasushi
Y
Division of Experimental Animals Research, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashimurayama-shi, Tokyo 208-0011, Japan.
Suzaki
Yuriko
Y
Division of Experimental Animals Research, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashimurayama-shi, Tokyo 208-0011, Japan.
Sata
Tetsutaro
T
Department of Pathology, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashimurayama-shi, Tokyo 208-0011, Japan.
Iwasaki
Takuya
T
Division of Clinical Investigation, Institute of Tropical Medicine, Nagasaki University, Nagasaki 852-8523, Japan.
Miyamura
Tatsuo
T
Department of Virology II, National Institute of Infectious Diseases, 4-7-1 Gakuen, Musashimurayama-shi, Tokyo 208-0011, Japan.
D020413:3' Untranslated Regions / Q000235:genetics / Q000502:physiology; D020121:5' Untranslated Regions / Q000235:genetics / Q000502:physiology; D000818:Animals; D001483:Base Sequence; D001921:Brain / Q000821:virology; D002478:Cells, Cultured; D020805:Central Nervous System Viral Diseases / Q000821:virology*; D004195:Disease Models, Animal; D004770:Enterovirus / Q000235:genetics* / Q000254:growth & development / Q000472:pathogenicity*; D004769:Enterovirus Infections / Q000821:virology*; D005260:Female; D008252:Macaca fascicularis; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D017955:Poliovirus / Q000235:genetics / Q000502:physiology; D012324:RNA-Dependent RNA Polymerase / Q000235:genetics / Q000502:physiology; D013116:Spinal Cord / Q000821:virology; D010948:Viral Plaque Assay; D014774:Virulence / Q000235:genetics*
D020413:3' Untranslated Regions; D020121:5' Untranslated Regions; C090443:polymerase 3Dpol, poliovirus; D012324:RNA-Dependent RNA Polymerase