Impact of cell culture sensitivity and virus concentration on rapid detection of herpes simplex virus by cytopathic effects and immunoperoxidase staining.

Tremendous interest has been generated in the commercial kits now available that incorporate herpes simplex virus isolation in cell culture with immunoperoxidase staining for viral antigen detection. Most studies comparing commercial kits with conventional cell culture techniques have found the kits to be less sensitive. However, different cell cultures were used for the two methods. In this study, mink lung, rabbit kidney, MRC-5, and Vero cells were compared for reisolation of herpes simplex virus from clinical specimens in which viral infectivity titers were concurrently determined. When specimens contained high titers of infectious virus, the cell system used made little difference and all specimens were detected by immunoperoxidase staining at 48 h postinoculation. However, when specimens contained low concentrations of virus, the differences in sensitivity between cell systems became apparent in rapidity of detection and overall isolation rate. Mink lung and rabbit kidney cells were both more sensitive than MRC-5 cells; Vero cells were significantly less sensitive than the other cells tested. The application of immunoperoxidase staining shortened the time to virus detection and lessened, but did not eliminate, the differences between the cell systems. Cytopathic effects alone in the most sensitive cell system equaled or exceeded immunoperoxidase staining applied in less-sensitive cell cultures.