Serotyping of herpes simplex virus isolates: a comparison of BVDU sensitivities, indirect immunofluorescence with monoclonal antibodies, and indirect immunofluorescence with cross-adsorbed rabbit antibodies.

Four methods for typing of herpes simplex virus (HSV) isolates were compared for 43 recent clinical isolates and 3 reference strains of HSV. These isolates were subjected to indirect immunofluorescence using both monoclonal antibodies and cross-adsorbed rabbit antisera. Sensitivity to E-5-(2-bromovinyl)-2'-deoxyuridine (BVDU) was also examined. All isolates which fluoresced with HSV-1 monoclonals were found to be sensitive to BVDU with ID50's ranging from 0.001 to 0.006 micrograms/ml. All isolates labelled as HSV-2 using monoclonal antibodies had ID50's to BVDU ranging from 0.4 to 3.5 micrograms/ml. Results of typing with rabbit cross-adsorbed antisera were less accurate, however. When dilutions were predetermined according to manufacturer's instructions, only 3 of 22 isolates (14%) of HSV-1 were correctly typed. HSV-2 isolates were correctly labelled in 24 of 26 situations (92%). When fluorescence dilution endpoints were compared, however, 21 of 22 (95%) HSV-1 isolates had fluorescence endpoints at a greater dilution with HSV-1 antiserum. Twenty-three of 24 HSV-2 isolates were also correctly typed (96%).