Hematological and febrile responses of rabbits to listerial hemolysins.

The effects of an infusion of partially purified hemolysin (9-125) from Listeria monocytogenes were studied in intact rebbits. A similar preparation from trypticase soy broth (TSB) was employed for control purposes. Alterations of several blood constituents and febrile responses resulting from both of these products were noted. After administration of hemolysin into the blood stream, profound leukopenia, marked reduction of platelets, and changes in the blood constituents were recorded. The data comparing the effect of both hemolysin and TSB are presented. Both groups exibited pyrogenic responses. The test animals had elevated temperatures for up to 24 hours while the control group had temperature almost in normal range within eight hours of injection. Pyrogenic responses and changes in the constituents of peripheral blood suggest that the hemolysins possess cytotoxic activity and thus may play a role in the pathogenesis of Listeria monocytogenes in the disease process.