Oral Immunization with Recombinant Lactobacillus acidophilus Expressing the Adhesin Hp0410 of Helicobacter pylori Induces Mucosal and Systemic Immune Responses

Abstract

Helicobacter pylori infection is relatively common worldwide and is closely related to gastric mucosa-associated lymphoid tissue (MALT) lymphoma, chronic gastritis, and stomach ulcers. Therefore, a safe and effective method for preventing H. pylori infection is urgently needed. Given that developing an effective vaccine against H. pylori is one of the best alternatives, H. pylori adhesin Hp0410 was expressed in the food-grade bacterium Lactobacillus acidophilus. The recombinant live bacterial vaccine was then used to orally vaccinate mice, and the immunoprotective effects of Hp0410-producing strains were investigated. H. pylori colonization in the stomach of mice immunized with the recombinant L. acidophilus was significantly reduced, in comparison with that in control groups. Furthermore, mucosal secretory IgA antibodies were elicited in the mucosal tissue of mice immunized with the recombinant bacteria, and specific anti-Hp0410 IgG responses were also detected in mouse serum. There was a significant increase in the level of protection against gastric Helicobacter infection following a challenge with H. pylori Sydney strain 1 (SS1). Our results collectively indicate that adhesin Hp0410 is a promising candidate vaccine antigen, and recombinant L. acidophilus expressing Hp0410 is likely to constitute an effective, low-cost, live bacterial vaccine against H. pylori.

Immunization with r-Lactococcus lactisexpressing outer membrane protein A ofShigella dysenteriaetype-1: evaluation of oral and intranasal route of administration

“…Results described in this study are consistent with the findings of other researchers demonstrating the efficiency of oral route in IgA production (Hongying et al . ). Interestingly, Medina et al .…”

Growth phase-dependent composition of the Helicobacter pylori exoproteome

“…Several of the selectively released proteins, including VacA, HcpC (HP1098), and HP0231, are known to elicit an antibody response in H. pylori -infected humans (38–41). Some of these antigenic proteins, including VacA, HpaA paralog (HP0410), and HP0231, have been shown to elicit a protective immune response when administered as vaccine antigens in animal models (42–44). …”

Systematic review and meta-analysis: Multi-strain probiotics as adjunct therapy forHelicobacter pylorieradication and prevention of adverse events

“…507).'' 18 Some probiotics have mechanisms of action directed against H. pylori, including inhibiting H. pylori attachment to mucosal cells, [19][20][21] regulating the immune response to H. pylori, 22 or direct physiologic effects. 23 However, other studies found the use of probiotics did not improve the H. pylori eradication rates, 24,25 nor reduce the side-effects of antibiotic use.…”