Department of Molecular Biology, National Research Center, Dokki, Cairo, Egypt.
A new assay, the Cell-Associated Virus ELISA (CAV-ELISA) for detection of antiviral antibodies was established. The assay is based on using cell-associated virus antigens (CAV) as an alternative for the virus-senthetized ELISA plates. Smooth dose response curves were obtained for the binding of rabbit antipoliovirus antibodies with BGM associated poliovirus. At relatively high concentrations of CAV, superimposed dose response curves were reproducible over a wide range of virus concentrations, and binding become a function of serum concentration. At relatively lower concentrations of CAV the bound antibodies decreases with both the virus and antibody concentrations. Standard dose response curves expressing the binding of different antibody concentrations to the CAV were established and used for determination of the levels of antibodies in test samples. The interpreted titers from standard dose response curves were highly reproducible. Furthermore, the CAV-ELISA is as sensitive as the indirect ELISA and is minimally affected by the variations in virus preparation.