Abstract
A novel membrane filtration enzyme immunoassay (MF EIA) is described in which virus-antibody complexes formed are trapped onto the surface of membranes with low protein-binding affinity by vacuum filtration. Class-specific immunoglobulin G (IgG) or IgM antibody was measured by adding enzyme-conjugated antiimmunoglobulin and incubating prior to the final wash and addition of enzyme substrate. Influenza A virus-specific IgG antibodies measured by MF EIA showed similar sensitivity for detecting seroconversion in volunteers administered influenza virus subunit vaccines and subtype specificity comparable to that observed by the hemagglutination inhibition technique. Cytomegalovirus-specific IgG antibodies measured by MF EIA with commercially available complement fixation antigens gave results similar to those of conventional enzyme-linked immunosorbent assay and complement fixation tests. The MF EIA method is also suitable for detection of rotavirus antigen in feces.