45 - A simple ELISA for the estimation of antibodies to equine herpes virus (EHV-1) and its application to the quality control of vaccines

Abstract

An ELISA for the estimation of the EHV-1 antibody concentration in guinea pig- and horse sera was evaluated. The antigen preparation is based on the accumulation of structural viral proteins in the cytoplasm of infected cells and on the integrity of the cell membranes of infected cells in spite of the cytopathic effect (CPE). Thus, infected and mock infected cells may be grown under optimal nutritional conditions. Proteins added to the growth medium, e.g. fetal calf serum, that might interfere by competition during the coating of the antigen to the ELISA plates, can easily be removed by washings of the harvested cells. The cells are then treated with nonionic detergents under hypotonic conditions in order to disrupt the cell membranes but not the nuclear membranes. Nuclei are removed by centrifugation. The cytoplasm of infected and mockinfected cells, respectively, is coated alternatively to ELISA plates. Antibodies to EHV-1 are detected by antispecies antibodies and an avidinbiotin enhanced peroxidase system. The ELISA reaction is determined by the difference of the optical densities (Delta OD at 405 nm) of the wells containing infected and mock infected antigen.