Helicobacter pylori adhesins: HpaA a potential antigen in experimental vaccines for H. pylori

Abstract

Background Helicobacter pylori is a gram‐negative bacterium involved in many gastric pathologies such as ulcers and cancers. Although the treatment for this infection has existed for several years, the development of a vaccine is nevertheless necessary to reduce the severe forms of the disease. For more than three decades, many advances have been made particularly in the understanding of virulence factors as well as the pathogenesis of gastric diseases caused by H. pylori. Among these key virulence factors, specific antigens have been identified: Urease, Vacuolating cytotoxin A (VacA), Cytotoxin‐associated gene A (CagA), Blood group antigen‐binding adhesin (BabA), H. pylori adhesin A (HpaA), and others. Objectives This review will focus on H. pylori adhesins, in particular, on HpaA and on the current knowledge of H. pylori vaccines. Methods All of the information included in this review was retrieved from published studies on H. pylori adhesins in H. pylori infections. Results These proteins, used in their native or recombinant forms, induce protection against H. pylori in experimental animal models. Conclusion H. pylori adhesins are known to be promising candidate vaccines against H. pylori. Future research should be carried out on adhesins, in particular, on HpaA.

Identification of anti-Helicobacter pylori antibody signatures in gastric intestinal metaplasia

“…H. pylori hypB-deficient mutant exhibits significantly decreased urease activity as there is a physical interaction between urease and HP0900/HypB [30]. HpaA is a lipoprotein in the flagellar sheath and outer membrane and plays an essential role in the adhesion and colonization of the gastric mucosa [31]. Although poorly characterized, HP0709 encodes an enzyme that is involved in either DNA methylation or synthesis of some branched amino acids.…”

Detection and Treatment of Helicobacter pylori: Problems and Advances

“…Vaccination against H. pylori would be effective to achieve prophylaxis or eradication and reduce the prevalence of gastric diseases [ 108 ]. A prophylactic or therapeutic vaccine needs the selection and combination of immunogenic bacterial antigens with effective adjuvants and its administration via an available route [ 109 ]. The main antigens related to vaccines are CagA, VacA, BabA, HpaA, NapA, OipA, GGT, HspA, Omp, and FliD [ 110 ], and their combinations of multivalent epitopes with adjuvants, usually composed of CD4 + and CD8 + epitopes [ 111 ] (e.g., CTB-UE, CWAE vaccine [ 112 ], CFdAE vaccine [ 113 ], FVPE vaccine [ 114 ], HUepi-LTB vaccine [ 115 ], LHUC-LTB [ 116 ], and CTB-HUUC vaccine [ 117 ]).…”

Embedding of exogenous B cell epitopes on the surface of UreB structure generates a broadly reactive antibody response againstHelicobacter pylori

“…A linear B cell epitope of the movement-related protein flagellin A (FlaA) was also identified by experiment 12 . H. pylori adhesins including sialic acid-binding adhesin (SabA), hop family adhesin AlpB (AlpB), and H. pylori adhesin A (HpaA) are known to be promising candidate vaccine antigens against H. pylori 13 . Their possible conservative adhesion domains have also been reported in the previous studies 14–16 .…”