Simultaneous detection of different serum pepsinogens and its primary application

AIM: To develop the simple, rapid and sensitive dual-label time-resolved fluoroimmunoassay for pepsinogens in human serum. METHODS: Based on two-site sandwich protocol, monoclonal antibodies (McAbs) against pepsinogen I (PG I) and PG II were co-coated in 96 microtitration wells, and tracer McAbs against PG I and PG II were labeled with europium (Eu) and samarium (Sm) chelate, respectively. Diluted serum samples of Eu(3+)- and Sm(3+)-McAbs were added into microtitration wells simultaneously. After washing, fluorescence of bound Sm(3+) and Eu(3+) tracers was detected. RESULTS: The detection limit was 0.2 microg/L for PG I and 0.05 microg/L for PG II. The assay range was 5.0-320.0 microg/L for PG I and 1.0-55.0 microg/L for PG II. The average recovery rate was 102.7% for PG I and 98.8% for PG II. Sera from healthy controls and patients with gastric disease were analyzed. The PG detected by dual-label assay was in good agreement with that detected by single-label assay or by enzyme-linked immunosorbent assay. CONCLUSION: Dual-label assay can provide high-throughput serological screening for gastric diseases.