BACILLUS-THURINGIENSIS-VAR-ISRAELENSIS CRYSTAL DELTA-ENDOTOXIN - EFFECTS ON INSECT AND MAMMALIAN-CELLS INVITRO AND INVIVO

  • 1 January 1983
    • journal article
    • research article
    • Vol. 60  (MAR) , 181-197
Abstract
B. thuringiensis var. israelensis parasporal crystal .delta.-endotoxin was purified by ultracentrifugation on a discontinuous sucrose gradient. Native .delta.-endotoxin crystals showed no detectable toxicity in the in vitro and in vivo systems that are described. Alkali-solubilized crystal .delta.-endotoxin caused rapid cytological and cytopathological changes in Aedes albopictus, Choristoneura fumiferana 63 CF1, Spodoptera frugiperda and Trichoplusia ni cell lines as observed by phase-contrast microscopy and vital staining. Mouse fibroblasts, primary pig lymphocytes and 3 mouse epithelial carcinoma cell types showed a similar response to the alkali-soluble crystal .delta.-endotoxin. The soluble crystal .delta.-endotoxin protein caused hemolysis of rat, mouse, sheep, horse and human erythrocytes. Administration i.v. of the alkali-soluble crystal .delta.-endotoxin to Balb.c mice at a dose rate of 15-30 .mu.g of protein/g body weight resulted in rapid paralysis followed by death within 12 h. Inoculation s.c. of 15-30 .mu.g of protein/g body weight resulted in death of suckling mice in 2-3 h. The alkali-solubilized crystal .delta.-endotoxin was not toxic when administered per os. A comparison is made with a similar alkali-soluble fraction from the parasporal crystal .delta.-endotoxin of B. thuringiensis var. kurstaki. With the exception of the Lepidopteran cell line, C. fumiferana 63 CF1, this soluble crystal .delta.-endotoxin protein showed no in vitro or in vivo toxicity and no hemolytic activity.