Demonstration of an immunosuppressive action of detergent-disrupted influenza virus on the antibody response to inactivated whole virus vaccine

In a series of experiments performed in hamsters and mice, administration of mixtures of detergent-disrupted (SV) influenza A X49 (H3N2) virus and inactivated X49 whole virus (WV) vaccine induced lower serum antibody titres than equivalent or lower doses of WV vaccine alone. This reduction in antibody titre was also observed using influenza A (H1N1) and influenza B (B/Hong Kong/8/73) SV and WV vaccine preparations. The results suggested that SV preparations can suppress the serum antibody response to WV vaccine. A suppressive effect of SV influenza virus on WV vaccine was also observed in an in vitro antibody-forming system, using primed mouse spleen cells. In this system, SV induced markedly lower IgG and IgM antibody responses than WV vaccine, and mixtures of SV with WV reproducibly resulted in lowered antibody responses compared to those elicited by WV alone. Possible reasons for these findings are discussed in the light of the known low immunogenicity observed for split and subunit influenza virus vaccine preparations in animals and in unprimed human populations.