title: Posintro™-HBsAg, a modified ISCOM including HBsAg, induces strong cellular and humoral responses.
abstract: To improve the hepatitis B vaccines on the market new adjuvant systems have to substitute aluminium. In this study the hepatitis B surface antigen (HBsAg) was incorporated into a novel adjuvant system, the Posintro™, a modification of the traditional immune stimulatory complexes (ISCOMs). This new HBsAg vaccine formulation, Posintro™-HBsAg, was compared to two commercial hepatitis B vaccines including aluminium or monophosphoryl lipid A (MPL) and the two adjuvant systems MF59 and QS21 in their efficiency to prime both cellular and humoral immune responses. The Posintro™-HBsAg induced the strongest humoral response with high titers of HBsAg specific antibody, high number of antigen specific B-cells and a strong T helper 1 (Th1) antibody profile when compared to the other adjuvant formulations. The Posintro™-HBsAg was also a strong inducer of cellular immune responses with induction of delayed type hypersensitivity (DTH) reaction and CD4(+) T-cell proliferation. In addition, Posintro™-HBsAg was the only vaccine tested that also induced a strong cytotoxic T lymphocyte (CTL) response, with high levels of antigen specific CD8 T-cells secreting IFN-gamma mediating cytolytic activity. The results demonstrate that this novel experimental vaccine formulation, the Posintro™-HBsAg, is strongly immunogenic and can induce both class I and class II responses in experimental animals. This shows promise both for the protection against hepatitis B virus infection and as a potential therapeutic vaccine.
authors: Nordic Vaccine A/S, Fruebjergvej 3, 2100 Copenhagen, Denmark. schiott.aasa@gmail.com
authors: Asa
authors: A
authors: Schiött
authors: Kristina
authors: K
authors: Larsson
authors: Søren
authors: S
authors: Manniche
authors: Suzanne
authors: S
authors: Kalliomäki
authors: Annette Vinther
authors: AV
authors: Heydenreich
authors: Kristian
authors: K
authors: Dalsgaard
authors: Nikolai
authors: N
authors: Kirkby