Development of in vitro methods for the potency testing of clostridial vaccines

Cell culture assays, using the MDCK cell line was confirmed as being sensit ive to the C. perfringens epsilon toxin and VERO cell line to the C. novyi type B alpha toxin. Cell culture assays using these cells were developed an d the test conditions were standardised. The antitoxin titres of rabbit ant isera were calculated anc compared with those of the manufacturers. The cor relation coefficients between in vitro and in vivo method were calculated a nd were significant. The cell culture assay offers a valid in vitro alternative tot the animal e xperiments for the titration of sera generated in the course of potency tes ts of clostridial vaccines.