Abstract
We have developed an enzyme-linked immunosorbent assay for murine leukaemia virus using methanol-fixed cells as antigen. Specific antisera clearly recognized viral antigens within cells adherent to the microtitre plates. This test was used to quantify infection, to monitor virus multiplication and to demonstrate virus neutralization by antisera. The ELISA was as sensitive as, and faster and easier to perform than, the XC plaque assay and could even quantify large amounts of virus. It can easily be adapted for assaying other viruses.