Progress in vaccine development againstHelicobacter pylori

Abstract

Based on the very high prevalence of diseases caused by Helicobacter pylori, particularly in the developing world, and the rapid emergence of antibiotic resistance among clinical isolates, there is a strong rationale for an effective vaccine against H. pylori. In this review we describe recent promising candidate vaccines and prophylactic or therapeutic immunization strategies for use against H. pylori, as well as studies to identify immune responses that are related to protection in experimental animals. We also describe identification of different types of immune responses that may be related to protection against symptoms based on comparisons of H. pylori-infected patients with duodenal ulcers or gastric cancer and asymptomatic carriers. We conclude that there is still a strong need to clarify the main protective immune mechanisms against H. pylori as well as to identify a cocktail of strong protective antigens, or recombinant bacterial strains that express such antigens, that could be administered by a regimen that gives rise to effective immune responses in humans.

A Double Mutant Heat-Labile Toxin from Escherichia coli, LT(R192G/L211A), Is an Effective Mucosal Adjuvant for Vaccination against Helicobacter pylori Infection

“…In the past decade, several vaccine candidates against H. pylori have been evaluated in animal models (2). We and others have shown that, besides specific H. pylori antigens, an effective adjuvant is needed to induce protection against H. pylori infection after mucosal immunization (2,3).…”

“…We and others have shown that, besides specific H. pylori antigens, an effective adjuvant is needed to induce protection against H. pylori infection after mucosal immunization (2,3). Thus, immunization with whole-cell or lysate preparations of H. pylori together with adjuvants such as cholera toxin (CT) or heat-labile toxin (LT) and in some cases also mutant forms of the toxins confers protection against H. pylori infection (2,4). CT, most often used in the preclinical evaluation of mucosal candidate vaccines, promotes strong T cell as well as B cell responses to vaccine components and is a golden standard for testing alternative mucosal adjuvants.…”

Helicobacter pylori Infection of the Gastric Mucosa

“…The explanation for these differences may be related to the fact that the C57BL/6 mice are prone to developing a Th1 polarized T cell response and BALB/c mice a Th2 type of response. Infection of C57BL/6 mice with H. pylori strain SS1 is by far the most robust and reproducible of all mouse models and has been extensively used to study vaccine-induced immune responses and protection against H. pylori infection (reviewed in Svennerholm and Lundgren, 2007;Muller and Solnick, 2011;Zawahir et al, 2013).…”

Prevention of cancer through immunization: Prospects and challenges for the 21st century

“…The development of resistance would presumably be a less likely shortcoming for an effective vaccine. In murine models, immune responses induced to bacterial urease [50] protect against oral challenge with Helicobacter, suggesting that a prophylactic vaccine against Helicobacter might be possible [51]. However, clinical trials with single antigens have thus far been disappointing, which has stimulated efforts to consider vaccines composed of several antigens.…”