A microplate immunoenzyme assay for anti-influenza antibodies.

An enzyme-linked immunosorbent assay (ELISA) using horseradish peroxidase is described for the detection and quantitation of anti-influenza virus antibodies. Compared with complement fixation and hemagglutination inhibition tests, ELISA is far superior with respect to sensitivity and reliability. Non-specific viral inhibitors present in sera do not affect the titer in ELISA. Its sensitivity, close to that of radioimmunoassay permits detection of small amounts of antibodies in pulmonary secretions and supernatants from in vitro spleen cell cultures.