Pathogenetic role of the tyrosine-phosphorylated CagA EPIYA sequence of Helicobacter pylori in histological gastritis in Japanese patients

Abstract

CagA-P is an antigen-peptide against the host, and serum titer of anti-CagA-P antibody may be a new marker for gastritis in the corpus.

Relationship between Helicobacter pylori Tyrosine-Phosphorylated CagA-Related Markers and the Development of Diffuse-Type Gastric Cancers: A Case-Control Study

“…As shown in table 3, we could not demonstrate any differences in these classical serological markers between the AG group and the DGC group. We previously confirmed that the titers of anti-CagA-P antibodies in the sera of H. pylori -positive patients were statistically higher than those of H. pylori -negative patients [12]. Interestingly, we found that the serum titer of anti-CagA-P antibody in the patients of the DGC group was statistically higher than the titer of those of the AG group, especially in females (p< 0.05, fig.…”

“…The slides were incubated in 0.1% trypsin (Becton, Dickinson and Company) for 30 min at 37°C for antigen retrieval [16] followed by an immunoreaction with the primary antibody in PBS overnight at 4°C. We used originally raised anti-CagA-P antibody (OF-515) as the primary antibody with a 1:200 dilution [12]. After immunohistochemical staining had been performed using the LSAB2 System-HRP kit (Dako, Kyoto, Japan), the sections were finally lightly counterstained with Mayer’s hematoxylinsolution (Merck KGaA, Germany), intensified,dehydrated, and mounted for quantitative analysis.…”

“…A 10-mer oligo-peptide (CEPIY (P) ATIDF; CagA-P) designed from the East Asian CagA-specific EPIYA-D site was synthesized as previously described [12]. The serum titer against CagA-P was evaluated by an enzyme-linked immunosorbent assay (ELISA) using CagA-P as an antigen.…”

“…As described above, a simple subclassification of CagA diversity may be insufficient, so we tried to evaluate the ‘quantity’ of CagA in DGC patients and to find a new biological marker for CagA. Recently, we synthesized an oligopeptide (CEPIY (P) ATIDF; CagA-P) based on the East Asian CagA-specific EPIYA-D as an antigen and raised a polyclonal antibody against CagA-P [12]. Moreover, we clarified that the serum titer against CagA-P was correlated with the degree of gastritis, which is linked to the carcinogenic risk [12].…”

“…Recently, we synthesized an oligopeptide (CEPIY (P) ATIDF; CagA-P) based on the East Asian CagA-specific EPIYA-D as an antigen and raised a polyclonal antibody against CagA-P [12]. Moreover, we clarified that the serum titer against CagA-P was correlated with the degree of gastritis, which is linked to the carcinogenic risk [12]. In the present study, we constructed a case-control study and investigated whether these CagA-P-related markers [(1) the serum titer of anti-CagA-P antibody and (2) the expression level of CagA-P in the gastric mucosa] are linked to DGC carcinogenesis.…”