Th type immune response induced by Helicobacter pylori vaccine in mice
- VernacularTitle:幽门螺杆菌疫苗免疫小鼠的Th免疫应答及作用
- Author:
Jie CHEN
;
Minhu CHEN
;
Guoqing LI
;
Al ET
;
- Publication Type:Journal Article
- Keywords:
Helicobacter pylori;
Vaccine;
Cholera toxin;
Immune response;
Post immunization gastritis
- From:
Chinese Journal of Digestion
2001;0(12):-
- CountryChina
- Language:Chinese
-
Abstract:
Objective To study the protective immune response induced by Helicobacter pylori (H. pylori) vaccine in mice. Methods Mice were orally immunized with cholera toxin(CT) plus H. pylori whole cell sonicate antigen, CT or normal saline(NS) respectively. Four weeks after immunization mice were challenged with H. pylori. Mice were sacrificed at different time points before and after challenge. Gastric H. pylori colonization, serum anti H. pylori IgG1, IgG2a and IgA antibodies, mRNA expressions of Th1 type cytokines including interferon(IFN) ?, interleukin(IL) 2, IL 12 and Th2 type cytokines including IL 4, IL 6, IL 10 in gastric mucosa and spleen, and gastric inflammation at different time points were all compared in different groups. Results (1) H. pylori colonization in CT plus sonicate antigen group was decreased significantly compared with CT group and NS group both 5 and 26 weeks after challenge. (2)The serum levels of anti H. pylori IgG1, IgG2a and IgA of CT plus sonicate antigen group were significantly higher than those of CT group and NS group at all time points. (3)The mRNA expression levels of Th1 type cytokines in the gastric mucosa of CT plus sonicate antigen group and CT group were higher than that of NS group both before and 5 weeks after H. pylori challenge. 26 weeks after the challenge, Th1 type cytokines in the gastric mucosa of NS group were increased, but those in the gastric mucosa of CT plus sonicate antigen group and CT group were decreased except for IL 12. (4)Before the challenge, Th2 type cytokines were expressed similarly in the gastric mucosae of both CT plus sonicate antigen group and CT group. 5 weeks after the challenge, IL 4 and IL 10 expressions were not detected in CT plus sonicate antigen group and CT group and the expression of IL 6 was lower than that of NS group. 26 weeks after the challenge, both IL 4 and IL 10 expressed again in CT plus sonicate antigen group, but only IL 10 expressed again in CT group. The expressions of IL 6 were similar in all groups. (5) Both Th1 and Th2 type cytokines were expressed in the spleen of all groups at different time points without significant difference. (6) Significant gastritis characterized by marked infiltration of lymphocyte, neutrocyte and mononuclear cells was found in CT plus sonicate antigen group 5 weeks after challenge. In CT group mild inflammation was also found. 26 weeks after the challenge, gastritis in NS group was exacerbated but gastritis in the other two groups was alleviated.Conclusions (1)Vaccine consisting of both H. pylori whole cell sonicate antigen and CT may induce both Th1 and Th2 type immune response at early stage. (2)The increased early Th1 response after H. pylori challenge may contribute to both the protective immunity and post immnization gastritis. Later, the Th2 response after the challenge increases, as Th1 response and post immnization gastritis both abated.
