Gringorten J L, Witt D P, Milne R E, Fast P G, Sohi S S, van Frankenhuyzen K
Forest Pest Management Institute, Sault Ste. Marie, Ontario, Canada.
J Invertebr Pathol. 1990 Sep;56(2):237-42. doi: 10.1016/0022-2011(90)90106-g.
A cell assay system was developed that allows Bacillus thuringiensis delta-endotoxins activated at high pH (10.5) to be tested in vitro without causing alkaline injury to target cells. The assay is carried out on a lawn of gel-suspended cells, requires only 1 microliter of sample per dose, and is quantitative, rapid, and sensitive. The threshold dose for toxicity of B. thuringiensis subsp. kurstaki HD-73 with IPRI-CF-1 cells was 24 pg protein. The assay is also very useful for identifying antibodies which inhibit toxicity and for detecting beta-exotoxin.
