A SENSITIVE AND SPECIFIC ELISA IMMUNOCAPTURE ASSAY FOR RAPID QUANTITATION OF INFLUENZA A H3N2 NEURAMINIDASE PROTEIN/

Both HA and NA proteins elicit antibodies which have been shown to be capable of altering the course of infection. Nevertheless, while influ enza virus vaccine standardization involves hemagglutinin (HA) and neu raminidase (NA) in terms of antigenic characterization, only HA protei n quantitation is undertaken. An immunocapture ELISA (EIA) is describe d for N2 NA quantitation, based on the use of a highly specific monocl onal antibody (MAb) for capturing NA and an anti-NA antiserum for anti gen detection. The amounts of NA in samples were deduced from the stan dard curve established by using purified NA. The NA-EIA is specific an d detects as a little as 7 ng/ml. The capture and detector antibodies directed against A/Beijing/32/92 NA were shown to react with H3N2 prot otype strains used in current influenza vaccines, provided that an ant igenically matched reference NA is used as standard. (C) 199S Elsevier Science B.V. All rights reserved.