FLOW CYTOMETRIC ASSAY FOR CYTOTOXIC ACTIVITY OF CRUDE CLOSTRIDIUM-PERFRINGENS ENTEROTOXIN USING NONADHERENT CELL FM3A

The flow cytometric assay method was tested for the cytotoxic activity of Clostridium perfringens enterotoxin (CPE) in culture using mouse m ammary carcinoma cell line FM3A stained with propidium iodide (PI). Fr om the results obtained, FM3A cells proved to be susceptible to CPE. A reproducible dose-response curve with FM3A was obtained between crude CPE at 13.9-109 ng/ml and between purified CPE at 40-400 ng/ml, respe ctively. These findings indicate that non-adherent FM3A is preferable to determine the cytotoxic activity of CPE because it can be used with out detachment procedures with trypsinin compared with adherent Africa n monkey kidney cell line (Vero cells), Furthermore, the flow cytometr y with non-adherent cell FM3A stained with PI only proved to be a usef ul method to determine the biological activity of CPE in culture isola tes.