Role of humoral immune response in the protection induced by H.pylori vaccine with chitosa as adjuvant / 中国病理生理杂志

ABSTRACT

AIM: To study the immunological protection of H. pylori vaccine with chitosa as adjuvant. METHODS: One-grade female BALB/c mice were randomly divided into nine groups and immunized by ①PBS alone; ②chitosan solution alone; ③chitosan particles alone; ④H. pylori antigen alone; ⑤H. pylori antigen plus chitosan solution; ⑥H. pylori antigen plus chitosan particles; ⑦H. pylori antigen plus CT; ⑧H. pylori antigen plus chitosan solution and CT; ⑨H. pylori antigen plus chitosan particles and CT. At 4 weeks after the last immunization, these mice were challenged by alive H. pylori(1?1012CFU/L) twice at two-day intervals. At 4 weeks after the last challenge, these mice were all killed and gastric mucosa were embedded in paraffin, sectioned and assayed with Giemsa staining. The other gastric mucosa were used to quantitatively culture with H. pylori. ELISA was used to detect H.pylori IgA in saliva and gastric mucosa and anti-H.pylori IgG, IgG1, IgG2a in serum, and immunohistochemical method was used to examine sIgA in gastric mucosa. RESULTS: ①In the groups with chitosan as adjuvant, 60% mice achieved immunological protection, which was according to that with CT as adjuvant (58.33%), and was significantly higher than H. pylori antigen alone and other groups without H. pylori antigen(P0.05)and were significantly higher than those in non-adjuvant groups, while those in the groups with chitosan plus CT were significantly higher than those in the group with CT as an adjuvant(P