Detection of clostridium toxins from tissues

Abstract

This investigation was designed to determine the feasibility of using mouse lethal test, skin necrotizing test in guinea pigs, lecithovitellin test and agar gel diffusion test as means of identification of clostridial toxins in animal tissues. Three species (four serotypes) of Clostridium thought to be involved in the sudden death syndrome of feedlot cattle were studied. They were Clostridium novyi types A and B, Clostridium perfringens types C and D and Clostridium sordellii. The toxins were produced in specified media for 24 to 48 hours. Culture supernatants for use in the various tests were prepared by centrifugation and sterilized by Seitz filtration. Preliminary experiments revealed that the mouse lethal test and the skin necrotizing test were suitable for detecting and differentiating the toxins of the three species studied because of their sensitivity and specificity. These results were exactly reproduced using tissues of mice experimentally inoculated with clostridial culture filtrates. The lecithovitellin tube test used in this study was unsuitable for typing clostridial toxins because it lacked specificity, required excessive antiserum and tissue components in extracts from experimental animals interfered with the reactions. The agar gel precipitation test cannot be recommended as a diagnostic method in detecting clostridial toxins from tissues because concentrated preparations of toxin were needed to produce precipitin lines and because some cross reactions were seen. Comparison of the two biological methods for detecting toxins revealed that the mouse test was more sensitive than the skin test with C. perfringens type D and C. novyi type B and that the skin necrotizing test was twice as sensitive as the mouse test with C. perfringens type C. With C. sordellii the skin test was slightly more sensitive than the lethal test in mice.