Studies investigating West Nile virus (WNV) NS4B protein function are hindered by the lack of an antibody recognizing WNV NS4B protein. Few laboratories have produced WNV NS4B antibodies, and none have been shown to work consistently. In this report, we describe a NS4B antibody against Japanese encephalitis virus (JEV) NS4B protein that cross-reacts with the NS4B protein of WNV but not of dengue virus (DENV). This JEV NS4B antibody not only recognizes WNV NS4B in infected cells, but also recognizes the NS4B protein expressed using transfection. It is evident from this data that the JEV NS4B antibody is specific to NS4B of WNV but not to NS4B of the four DENV serotypes. The specificity of this antibody may be due to the notable differences that exist between the amino acid sequence identity and antigenic relationships within the NS4B protein of the WNV, DENV, and JEV.
Keywords: JEV NS4B antibody; Japanese encephalitis virus; NS4B; West Nile virus; cross-reactivity; flavivirus; immunoassays.