Mariko Tanaka

Detection of West Nile and Japanese Encephalitis Viral Genome Sequences in Cerebrospinal Fluid from Acute Encephalitis Cases in Karachi, Pakistan

Reverse transcriptase‐polymerase chain reaction (RT‐PCR) on 24 cerebrospinal fluid (CSF) specimens collected between February and August 1992 detected genome sequence of West Nile (WN) virus in 8 specimens and Japanese encephalitis (JE) virus in a single specimen. The results, combined with the data by IgM‐ELISA on CSF indicated that a significant proportion of acute encephalitis cases in Karachi, Pakistan, were caused by WN virus infection, while JE virus caused a small fraction.

Japanese Encephalitis Virus Fusion Protein with Protein A Expressed in Escherichia coli Confers Protective Immunity in Mice

A complementary DNA (cDNA) that codes C‐terminal, one‐third of envelope glycoprotein (E) and N‐terminal 65 amino acids of NS1 protein of Japanese encephalitis (JE) virus was inserted into Escherichia coli expression vector pRIT2T. The inserted gene was expressed as a fusion protein with protein A, and the expressed protein was intraperitoneally injected into mice. The immunized mice produced anti‐JE antibodies measured by the hemagglutination‐inhibition and neutralization tests as well as ELISA and were protected from the lethal challenge of JE virus by intraperitoneal inoculation.