title: Oral immunization with recombinant Mycobacterium smegmatis expressing the outer membrane protein 26-kilodalton antigen confers prophylactic protection against Helicobacter pylori infection.
abstract: Helicobacter pylori infection is prevalent worldwide and results in chronic gastritis, which may lead to gastric mucosa-associated lymphoid tissue lymphoma and gastric cancer. We have previously reported that oral immunization with recombinant Mycobacterium smegmatis expressing the H. pylori outer membrane protein 26-kilodalton (Omp26) antigen affords therapeutic protection against H. pylori infection in mice. In the present study, we investigated the prophylactic effects of this vaccine candidate on H. pylori challenge in mice. We found that oral immunization with recombinant Mycobacterium Omp26 significantly reduced H. pylori colonization in the stomach compared to inoculation with wild-type M. smegmatis in control mice. Six of the recombinant Mycobacterium-immunized mice (60%) were completely protected from H. pylori infection. The severity of H. pylori-associated chronic gastritis assessed histologically was significantly milder in mice vaccinated with recombinant Mycobacterium than in control animals. Mice immunized with recombinant Mycobacterium showed enhanced antigen-specific lymphocyte proliferation and antibody responses. Moreover, immunization with recombinant Mycobacterium resulted in an increased expression of interleukin-2 and gamma interferon in the stomach and spleen, as determined by reverse transcription-PCR analysis. Our results collectively suggest that vaccination with recombinant Mycobacterium Omp26 confers prophylactic protection against H. pylori infection. The inhibition of H. pylori colonization is associated with the induction of antigen-specific humoral and cell-mediated immune responses.
authors: Department of Gastroenterology, Second Affiliated Hospital, Chongqing Medical University, Chongqing, China.
authors: Lin
authors: L
authors: Lü
authors: Han-qing
authors: HQ
authors: Zeng
authors: Pi-long
authors: PL
authors: Wang
authors: Wei
authors: W
authors: Shen
authors: Ting-xiu
authors: TX
authors: Xiang
authors: Zhe-chuan
authors: ZC
authors: Mei
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000276:immunology*; D001428:Bacterial Vaccines / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D049109:Cell Proliferation; D004337:Drug Carriers / Q000008:administration & dosage*; D005260:Female; D005753:Gastric Mucosa / Q000473:pathology; D020869:Gene Expression Profiling; D005822:Genetic Vectors; D016481:Helicobacter Infections / Q000276:immunology / Q000473:pathology / Q000517:prevention & control*; D016480:Helicobacter pylori / Q000235:genetics / Q000276:immunology*; D007249:Inflammation / Q000473:pathology / Q000517:prevention & control; D007371:Interferon-gamma / Q000096:biosynthesis; D007376:Interleukin-2 / Q000096:biosynthesis; D007963:Leukocytes, Mononuclear / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D020102:Mycobacterium smegmatis / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013154:Spleen / Q000276:immunology; D013270:Stomach / Q000276:immunology; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology
chemical_list: D001425:Bacterial Outer Membrane Proteins; D001428:Bacterial Vaccines; D004337:Drug Carriers; D007376:Interleukin-2; D014614:Vaccines, Synthetic; D007371:Interferon-gamma