Enhanced protection of mice against Japanese encephalitis virus infection by combinations of monoclonal antibodies to glycoprotein E

In the present study, the protective effect of various combinations of four monoclonal antibodies (MAbs) to glycoprotein E (gpE) of Japanese encephalitis virus (JEV) on the JEV-infected mice was studied. The MAbs were characterized as hemagglutination-inhibition-positive and JEV-specific (Hs). In the protective experiment, mice were first administered single MAbs or their combinations intraperitoneally (i.p.) and 24 hrs later infected with the virus intracerebrally (i.c.). The results showed that single MAbs protected the mice to the extent of 45-65%, while combinations of two or three MAbs gave 85-90% or 100% protection, respectively. The enhanced effect of combinations of several Hs MAbs might be due to the sharing of neutralization epitopes recognized by the Hs MAbs. These results suggested that a combination of at least three epitopes represented by the Hs MAbs should be included in an effective JEV vaccine.