Intranasal CpG‐Oligodeoxynucleotide is a Potent Adjuvant of Vaccine against Helicobacter pylori, and T Helper 1 Type Response and Interferon‐γ Correlate with the Protection

Abstract

CpG-ODN given intranasally is a potent adjuvant for development of a H. pylori vaccine. Th1-type response and IFN-gamma are involved in the protection.

Effects of a Th1- versus a Th2-biased immune response in protection against Helicobacter pylori challenge in mice

“…A previous study by Shi et al reported protection against H. pylori challenge using whole cell sonicate and CpG sequences [14]. Protection was associated with high levels of IgG2a and IFN-γ and was abrogated in IFN-γ knockout mice, which is in agreement with our results and emphasizes the importance of Th1 immunity for protection against H. pylori.…”

“…However, the LPS+/ CpG immunized mice were significantly more protected from challenge when compared to mock controls. Although the magnitude of this effect was modest, it was within the range of that seen in some other studies of H. pylori immunization [14,31,32].…”

“…This observation prompted early vaccine research to focus on the induction of T helper type 2 (Th2) immunity, since it was suspected that Th1 immunity prevented clearance from the host. Though some work supported this hypothesis [8], most studies suggest that in fact a strong Th1 biased environment, including increased gastritis, may be necessary for protection and clearance [13][14][15]. H. pylori vaccine studies using IL-4 knockout and B cell deficient mice have further supported this hypothesis, demonstrating that neither IL-4 nor antibody production (Th2 responses) are necessary for protection [13,16].…”

“…However, many vaccine studies that focused on inducing Th2 immunity used an H. pylori sonicate preparation that contained H. pylori LPS [14,[19][20][21]. Thus, these studies using H. pylori sonicate may not have optimally induced Th2 biased H. pylori specific immunity.…”

Vacunas en desarrollo: Helicobacter pylori

“…Lisados o sonicados de H. pylori, en conjunción con adyuvantes como TC, fueron capaces de provocar disminuciones significativas en la carga bacteriana 14 . Algunos grupos reportaron un efecto significativo en dicha reducción, asociado a la ruta de vacunación y al adyuvante empleado, siendo utilizada preferentemente la aplicación intranasal de los antígenos crudos 15,16 . La reciente utilización de los oligodesoxirribonucleótidos CpG como adyuvantes para evitar el efecto tóxico asociado a TC en humanos, ha sido evaluada por numerosos grupos observándo-se reducción significativa en la carga bacteriana 16,17 .…”