Immune evaluation of aSaccharomyces cerevisiae‐based oral vaccine againstHelicobacter pyloriin mice

Abstract

Background Helicobacter pylori (H. pylori) is a common human pathogenic bacterium that is associated with gastric diseases. The current leading clinical therapy is combination antibiotics, but this treatment has safety issues, especially the induction of drug resistance. Therefore, developing a safe and effective vaccine against H. pylori is one of the best alternatives. Objective To develop Saccharomyces cerevisiae (S. cerevisiae)‐based oral vaccines and then demonstrate the feasibility of this platform for preventing H. pylori infection in the absence of a mucosal adjuvant. Materials and Methods Saccharomyces cerevisiae (S. cerevisiae)‐based oral vaccines, including EBY100/pYD1‐UreB and EBY100/pYD1‐VacA, were generated and analyzed by Western blot, Immunofluorescence analysis, flow cytometric assay, and indirect enzyme‐link immunosorbent assay (ELISA). Further, antibody responses induced by oral administration of EBY100/pYD1‐UreB, EBY100/pYD1‐VacA, or EBY100/pYD1‐UreB + EBY100/pYD1‐VacA were measured in a mouse model. Lastly, the vaccinated mice were infected with H. pylori SS1, and colonization in the stomach were evaluated. Results Saccharomyces cerevisiae‐based H. pylori oral vaccines were successfully constructed. Mice orally administered with EBY100/pYD1‐UreB, EBY100/pYD1‐VacA, or EBY100/pYD1‐UreB + EBY100/pYD1‐VacA exhibited a significant humoral immune response as well as a mucosal immune response. Importantly, S. cerevisiae‐based oral vaccines could effectively reduce bacterial loads with statistical significance after H. pylori infection. Conclusions Our study shows that S. cerevisiae‐based platforms can serve as an alternative approach for the future development of promising bacterial oral vaccine candidates.

Lactic Acid-Producing Probiotic Saccharomyces cerevisiae Attenuates Ulcerative Colitis via Suppressing Macrophage Pyroptosis and Modulating Gut Microbiota

“…Nowadays, live biotherapeutic products (LBPs) are emerging as effective treatments for inflammatory diseases via improving nutrient absorption and the host defense system ( 19 ). Saccharomyces cerevisiae is a facultative anaerobic fungus that has been widely used to develop oral vaccines and engineered carriers in medicine ( 20 , 21 ). More studies have made it an engineering vector and transformed it to highly express small-molecule drugs ( 22 , 23 ).…”

How Long Will It Take to Launch an Effective Helicobacter pylori Vaccine for Humans?

“… 161 In H. pylori vaccine development, researchers applied S. cerevisiae to expressing recombinant UreB and VacA, and gained an oral vaccine against H. pylori , which showed significant humoral and mucosal immunoresponses and significantly reduced the colonization of H. pylori after vaccination in mice. 162 …”

Yeast oral vaccines against infectious diseases

“…However, many of them were also able to protect vaccinated animals against direct challenge from their target pathogen. These include candidate yeast oral vaccines against red-spotted grouper nervous necrosis virus in convict groupers ( Cho et al, 2017 ); Helicobacter pylori in mice ( Cen et al, 2021 ); cyprinid herpesvirus-3 in the common carp ( Ma et al, 2020 ); avian H5N1 influenza virus in chickens ( Lei et al, 2021b ); and white spot syndrome virus in shrimp ( Ananphongmanee et al, 2021 ), and among others. This growing list of successful animal vaccines suggests that cell-surface display is an effective technology for creating effective yeast oral vaccines.…”