Monocolonal antibody based flow cytometric method for the detection of enterotoxigenic clostridium perfringens

Abstract

An assay combining flow cytometry (FCM) and C. perfringens enterotoxin (CPE) specific monoclonal antibody ( MAb ) was developed for the detection of enterotoxigenic Clostridium perfringens. Biotin conjugated anti-CPE MAb and fluorescent avidin was used to study the sporangia I cells of C. perfringens, which were collected from 6-8 hour sporulation cultures. Using this assay. eight strains of C. perfringens which possessed the enterotoxin gene and belonged to distinct Hobb s types were analyzed.

FCM profiles of C. perfringens sporangia harvested from 6-8 hr sporulation cultures in Duncan and Strong (OS) medium revealed positive reaction for CPE. whereas vegetative cells and heat-treated sporangia of the same strain produced a negative reaction. Among eight different strains. high CPE producing strains showed high peak channel number and poor CPE producers demonstrated low peak channel numbers under FCM analysis. The flow cytometric method was found to be rapid, specific. accurate and reproducible. and can be used effectively in the detection of enterotoxigenic C. perfringens. Furthermore it might be of immense use in the diagnosis of food poisoning outbreaks.