070922 Modulation of the Th1/Th2 Bias by Lipopeptide and Saponin Adjuvants in Orally Immunized Mice (1)
On day 40 after three cluster applications, an increase of the specific IgG levels could be observed in sera of gliadin-free mice immunized with gliadin, or with gliadin in combination with both adjuvants. On day 80 after two further cluster applications, a further increase of gliadin-specific serum IgG could be detected.
In all three groups (gliadin, gliadin in combination with P3CSK4 or saponin) the gliadin-specific serum IgG1 levels (a) were increased on day 40 and 80. In the group immunized with gliadin in combination with P3CSK4, the specific IgG1 level was lower than in the group having received gliadin alone. The specific IgG2a level (b) was low in the group having received gliadin alone and increased in the group immunized with gliadin in combination with saponin and much more in the group immunized with gliadin in combination with P3CSK4.
On day 40 after 3 immunization clusters, an increase in gliadin-specific IgE levels could be detected in sera of groups immunized with gliadin alone or with gliadin in mixture with saponin. These enhanced IgE levels persisted until day 80. Remarkably, there was no increase of glia- din-specific IgE when the immunization was performed with gliadin in combination with P3CSK4.
The specific IgA level in sera of animals immunized with gliadin in combination with P3CSK4 was already enhanced on day 30 after 2 immunization clusters and increased with further immunizations. The immunization with gliadin in combination with saponin also led to an increase in specific serum IgA, starting on day 40 after three immunization clusters and increasing with further administrations.
Specific IgG levels in the group of gliadin in combination with saponin were also increased in the supernatants of Peyer’s patches and spleen. Mice having received gliadin, or gliadin in combination with P3CSK4, exhibited increased IgG levels especially in the supernatants of mesenteric lymph nodes. In the group immunized with gliadin in combination with saponin, the secret- ed IgA was increased especially in Peyer’s patches; in mesenteric lymph nodes a weak effect could be observed. The group having received gliadin in combination with P3CSK4 exhibited increased IgA levels especially in Peyer’s patches.
The mucosal adjuvant Cholera toxin is classified as a Th2-type adjuvant.