Development and evaluation of an in-house ELISA based on autochthonous antigens for detecting IgG anti-Helicobacter pylori in Cuban adults

Abstract

Aim: This study aimed to develop and evaluate an in-house enzyme-linked immunosorbent assay (ELISA) based on autochthonous antigens to detect immunoglobulin G (IgG) antibodies against Helicobacter pylori (H. pylori) in adult sera. Methods: Whole-cell antigens from three genetically characterized clinical isolates of H. pylori were mixed and used as coating antigens. This assay was validated with a panel of human sera samples of H. pylori seropositive and seronegative patients. Likewise, sera samples from patients with uninvestigated dyspepsia, who were also evaluated by invasive and noninvasive tests (i.e., histopathology, rapid urease test, and stool antigen test), blood donors and patients with confirmed viral and parasitic diseases were also collected. The IgG response against H. pylori was detected by the in-house assay using the commercial ELISA IBL (Germany), as a reference test. Statistical analysis was performed with GraphPad Prism version 5.01. Results: The in-house ELISA showed high repeatability and reproducibility. Sensitivity was 91.1%; 95% confidence interval (CI): 87.2–94.0, specificity was 94.8% (95% CI: 85.0–94.8), and accuracy was 91.6% (95% CI: 88.5–94.6). The in-house ELISA showed an excellent area under the curve (0.96; 95% CI: 0.93–0.98) and a better IgG detection by the inverse cumulative distribution. The frequency of seropositivity in patients with dyspepsia (76.0%) was significantly higher (P < 0.05) than in healthy individuals (57.7%) and patients with other infectious diseases resembling H. pylori infection symptoms (54.4%). The H. pylori seroprevalence was estimated to be 62.7%. A good correlation was found between IgG seropositivity and H. pylori infection diagnosed by histopathology, rapid urease test, and stool antigen test in Cuban adults with dyspepsia. Conclusions: The in-house ELISA demonstrated good diagnostic accuracy and potential usefulness for estimating H. pylori exposure in the adult population, henceforward, this method could be used as an alternative for H. pylori diagnosis in the Cuban setting.

Keywords

• diagnostic accuracy
• helicobacter pylori
• antibody detection
• elisa