Quantitative Real‐Time Immuno‐PCR Assay for Detection of Staphylococcus Aureus Enterotoxin H

Rapid, quantitative and sensitive detection methods are essential for prevention and risk assessment of food poisoning. In this study, we developed quantitative real‐time immuno‐polymerase chain reaction (qRT‐iPCR), a highly sensitive and efficient method for detection of staphylococcal enterotoxin H (SEH). The qRT‐iPCR is based on antigen–antibody recognition, similar to the traditional enzyme‐linked immunosorbent assay (ELISA). However, unlike ELISA, the method relies on DNA probes and RT‐PCR for detection rather than on a chromogenic reaction. We produced recombinant SEs and monoclonal antibodies for SEH. Then, coupled RT‐PCR using DNA probes was applied. This qRT‐iPCR showed a lower limit of detection (LOD) than traditional ELISA did. In the sandwich format, qRT‐iPCR system could detect approximately 4.5 pg/mL of SEH. Our qRT‐iPCR system simplified the detection and quantification of SEH and accelerated the process compared with traditional ELISA. To our knowledge, this is the most sensitive technique for detection of SEH reported to date. PRACTICAL APPLICATIONS: Sensitive and rapid commercial kits to detect and quantify staphylococcal enterotoxin H, which could not be detected by the existing kits, would be developed based on the quantitative real‐time immuno‐polymerase chain reaction method in this study and they can improve the process of risk assessment of food poisoning.