[Evaluation of immune prophylaxis of recombinant urease subunit of Helicobacter pylori].
OBJECTIVE
To evaluate the immune prophylaxis of recombinant urease subunit A or B (rUreA or rUreB).


METHODS
The BALB/C mice were divided into seven groups: negative control group, control group with CTB, control group with rUreA, control group with rUreB, experimental group with rUreA + CTB and experimental group with rUreB + CTB, experimental group with sonicate + CTB, which were gastrically inoculated with 150 ml PBS, 5 micrograms CTB, 50 micrograms rUreA, 50 micrograms rUreB, 50 micrograms rUreA + CTB, 5 micrograms rUreB + CTB and 400 micrograms sonicate + 5 micrograms CTB, respectively. Two weeks later, the mice were gastrically infected with H. pylori (10(7)-10(8) CPU per time). 4, 8 and 12 weeks later, the mice were killed and the immune protection of PBS, CTB, rUreA, rUreB, rUreA + CTB, rUreB + CTB and sonicate + CTB were evaluated by the presence of H. pylori in gastric tissue stained with Giemsa by microscopy. The mice in the side-effecting groups of rUreA + CTB and rUreB + CTB were not infected with H. pylori. 12 weeks later, the mice in the two groups were killed, and the side effects of rUreA + CTB and rUreB + CTB were evaluated by the infiltration of inflammation cells in gastric tissue stained with HE by microscopy.


RESULTS
The mice gastrically inoculated with CTB, rUreA or rUreB had significantly less H. pylori. The immune protective effect of rUreA, rUreB or sonicate of H. pylori combined with CTB was stronger than that of rUreA, rUreB or sonicate of H. pylori alone. The immune protective effect of rUreA + CTB occurred later than that of rUreB + CTB or sonicate of H. pylori + CTB. The mice immunized with rUreA + CTB, rUreB + CTB or sonicate of H. pylori + CTB were not completely protected against H. pylori infection. The mice immunized with rUreA + CTB, rUreB + CTB or sonicate of H. pylori + CTB were less infected with H. pylori, and had mild inflammation of gastric tissue.


CONCLUSIONS
Mice immunized with rUreA + CTB, rUreB + CTB or sonicate of H. pylori + CTB could not be completely protected against H. pylori infection and have alleviated inflammation of gastric tissue.
Shi
L
L
Digestive Disease Institute of PLA, Nanfang Hospital, Firest Military Medical University, Guangzhou 510515, China.
Wang
J
J
Chen
Y
Y
D000818:Animals; D005260:Female; D005753:Gastric Mucosa / Q000187:drug effects / Q000473:pathology; D016481:Helicobacter Infections / Q000276:immunology* / Q000517:prevention & control*; D016480:Helicobacter pylori / Q000201:enzymology*; D007114:Immunization; D051379:Mice; D008807:Mice, Inbred BALB C; D011994:Recombinant Proteins / Q000494:pharmacology; D014510:Urease / Q000494:pharmacology*
D011994:Recombinant Proteins; D014510:Urease