Development of serological assays to identifyHelicobacter suisandHelicobacter pyloriinfections

Abstract

BackgroundHelicobacter suis hosted by hogs is the most-prevalent gastric non-Helicobacter pylori Helicobacter species (NHPH) found in humans with gastric diseases. However, there is no reliable method for diagnosing H. suis infection in clinical practice without gastric biopsy specimens. MethodsHelicobacter infection was diagnosed by using routine methods for detecting H. pylori infection and three other methods (PCR, culture accompanied by genomic analyses, and microscopy) for detecting NHPH and H. pylori infection using gastric biopsy specimens. Then, an ELISA was developed to detect serum anti-H. suis and anti-H. pylori antibody titers. Findings The serum specimens (n=101) were divided into specimens with (n=20) and without H. suis infection (n=81), or into specimens with (n=17) or without H. pylori infection (n=64) after excluding H. pylori infection-eradicated specimens (n=20). The cut-off values of the optical density in the ELISA were used to judge Helicobacter infections. The sensitivity and specificity were 100% and 92.5%, respectively, for identifying H. suis infection, or 88.2% and 87.5%, respectively, for identifying H. pylori infection, and these levels were considered acceptable for clinical application. We detected no other NHPH infections by PCR or culture in this study. Interpretation We developed the world′s first ELISA to simultaneously diagnose H. suis and H. pylori infection, which is available for large-scale medical examination. The eradication of H. suis was confirmed by the time-dependent decline of anti-H. suis antibody titers. Funding This work was supported by MEXT/JSPS KAKENHI (JP19H03474, JP20K08365) and AMED (JP20fk0108148, JP20fk0108133).

Helicobacter pylori infection: a dynamic process from diagnosis to treatment

“…In view of the difficulty of culturing NHPHs from the human stomach, diagnosis is frequently based on microscopy and molecular analysis of biopsy samples. It is also possible to identify different gastric NHPHs by using the whole-cell ELISA method (Matsui et al, 2023). Despite other gastric Helicobacter species in the stomach causing many clinical conditions, they have been identified with a much lower prevalence.…”