Interference in Japanese encephalitis virus infection of Vero cells by a cationic amphiphilic drug, chlorpromazine.
Entry of Japanese encephalitis virus (JEV) into cells was analysed by using the vertebrate cell line Vero. Vero cells were treated with chlorpromazine, nystatin or cytochalasin D, which inhibit clathrin- and caveola-dependent endocytosis, and macropinocytosis of the cells, respectively. Productive JEV infection was inhibited by pretreatment with chlorpromazine; the number of JEV antigen-positive cells was less than one-fifth of that in untreated cultures, but was not significantly decreased by pretreatment with nystatin or cytochalasin. Viral antigens were detected in the membrane fractions, but not in the endosome fractions from chlorpromazine-treated JEV-inoculated cells. When the cells were treated with chlorpromazine, clathrin heavy chain antigen and JEV antigen were not detected in cytoplasm by indirect immunofluorescence staining. These results indicate that JEV is taken up by cells through the clathrin-dependent endocytic pathway, and this process leads to infection.
Nawa
Masaru
M
Department of Microbiology, Saitama Medical School, 38 Moroyama, Saitama 350-0495, Japan.
Takasaki
Tomohiko
T
Department of Virology 1, National Institute of Infectious Diseases, 1-23-1, Toyama, Shinjyuku, Tokyo 162-8640, Japan.
Yamada
Ken-Ichiro
KI
Department of Virology 1, National Institute of Infectious Diseases, 1-23-1, Toyama, Shinjyuku, Tokyo 162-8640, Japan.
Kurane
Ichiro
I
Department of Virology 1, National Institute of Infectious Diseases, 1-23-1, Toyama, Shinjyuku, Tokyo 162-8640, Japan.
Akatsuka
Toshitaka
T
Department of Microbiology, Saitama Medical School, 38 Moroyama, Saitama 350-0495, Japan.
D000818:Animals; D021941:Caveolae; D002522:Chlorocebus aethiops; D002746:Chlorpromazine / Q000494:pharmacology*; D002966:Clathrin / Q000378:metabolism*; D015638:Cytochalasin D / Q000494:pharmacology; D004664:Encephalitis Virus, Japanese / Q000187:drug effects / Q000302:isolation & purification / Q000472:pathogenicity*; D004705:Endocytosis / Q000187:drug effects* / Q000502:physiology; D019084:Fluorescent Antibody Technique, Indirect; D008854:Microscopy, Electron; D009761:Nystatin / Q000494:pharmacology; D014709:Vero Cells / Q000502:physiology / Q000821:virology
D002966:Clathrin; D009761:Nystatin; D015638:Cytochalasin D; D002746:Chlorpromazine