Table 1.

CD₅₀values for HK-2 and Vero cells

Time (h)	CD50
	HK-2 cells		Vero cells
	Stx1	Stx2	Stx1	Stx2
24	<100 fg/ml	300 fg/ml	800 pg/ml	>100 ng/ml
48	<100 fg/ml	6 pg/ml	300 fg/ml	2 ng/ml
72	<100 fg/ml	20 pg/ml	<100 fg/ml	<100 fg/ml