Humoral and cell-mediated immunity to Vero cell-derived influenza vaccine

A candidate trivalent influenza whole virus vaccine produced in a continuou s mammalian cell line (Vero), and analogous commercially available egg-deri ved vaccines, were compared for their ability to induce humoral and cell-me diated immunity in Balb/c mice. Substantial haemagglutination-inhibition ti tre and high levels of influenza virus-specific IgG were found in all group s of immunized mice, irrespective of the vaccine formulation. The IgG respo nses were predominantly of IgG1 and IgG2a/2b isotypes. Virus-specific secre tory IgA antibodies were detected only in mice immunized intranasally with a live virus, derived either from Vero cells or eggs. T-cell proliferative responses and T-helper 1 type cytokine release was significantly higher in mice immunized with Vero cell-derived influenza vaccine compared to egg-der ived vaccine formulations. We have demonstrated that the immunogenicity df the trivalent Vero cell-derived whole influenza virus vaccine was comparabl e to that of the equivalent egg-derived vaccine, with respect to humoral im mune response and was superior with respect to cellular response. (C) 2000 Elsevier Science Ltd. All rights reserved.