Quantitation of influenza vaccine hemagglutinin by immunoelectrophoresis.

A technique for the quantitation of hemagglutinin (HA) in influenza vaccines by immunoelectrophoresis (IEP) is described. This method gives accurate, and reproducible results and requires approximately 9 h to complete. The HA content of four manufacturers' vaccines correlated with the chick cell agglutination (CCA) values for each manufacturers' vaccine. However, when comparisons were made between vaccines produced by different manufacturers, up to a four-fold difference in HA content was observed. Comparison with single radial immunodiffusion (SRID) gave comparable results for vaccines produced by three of four manufacturers; the fourth manufacturers' vaccine gave 1.6-fold higher results by SRID. Human seroconversion rates in seronegative individuals correlated better with IEP determined HA content than the current assay of vaccine potency using CCA.