Antigen Optimization for H. pylori Vaccines

Ace Infectious provides antigen optimization services for H. pylori vaccines and offers two types of antigen optimization. One type is the optimization of antigen expression and the other is the optimization of antigen combinations. Both types of antigen optimization services are designed to improve immune efficacy and reduce harmful responses.

Optimization of antigen expression

Ace Infectious offers antigen expression optimization services to address the problem of DNA vaccines that do not express H. pylori antigen well and the low yield of H. pylori antigens when other expression systems are used. For example, we optimize the codon of the outer inflammatory protein gene (oipA) for Mus species codon usage which better enhances the expression of the antigen and stimulates immunity better. Besides codon optimization, we also enhance the expression of H. pylori antigens by co-expression. Since it is challenging and unsafe to obtain antigens from cultured H. pylori, we use safe bacteria strains, such as Lactococcus lactis, to express H. pylori antigens. Using gene editing and plasmid transformation techniques, we can successfully combine and express H. pylori antigens with favorable immunoreactivity.

Optimization of antigen combinations

Some of the H. pylori autoantigens can help to escape immunity or trigger tumors. For example, the outermost polysaccharide in H. pylori lipopolysaccharide has been shown to mimic host O-antigens, and this mimicry allows H. pylori to evade host immune detection by adhering to DC-SIGN on dendritic cells, leading to suppression of T-cell activation. Then, CagA could trigger tumors by affecting polarity-regulating kinase and two tumor suppressor proteins, p53 (ASPP2) and RUNX3. Thus, Ace Infectious provides antigen combination optimization and antigen residue combination optimization to solve those problems with the goal of stimulating more effective immunity while reducing side effects.

Take the example of antigen residue combination optimization, using in silico techniques and the H. pylori antigen database established by ourselves, we select relevant antigen residues for optimization and analyze the tertiary structure and characteristics of the combined antigens. Then, the safety and immunogenicity of combined antigens are verified by further in vitro experiments and in vivo animal experiments. Notably, our optimization covers not only antigen residues from H. pylori but also other toxic strains.

Learn more：H. pylori Vaccines Antigen Optimization