TABLE 1.

Comparison of cytotoxicity of different toxins in A459 cells

Toxin	IC50a		Increase in cytotoxicityb
	Empty vector	pcDNA3.1-TMX
	mol/liter	mol/liter	-fold
Ricin	5 × 10−10	10−11	50
Abrin	4 × 10−10	8 × 10−9	5
Pseudomonas exotoxin A	>10−8	6 × 10−9	<1.6
Saporin	>10−4	>10−4	<1

^a IC₅₀ is the concentration of toxin inhibiting 50% of the cell viability.

^b Fold increase in cytotoxicity is calculated as follows: IC₅₀ of cells transfected with empty vector/IC₅₀ of cells transfected with pcDNA3.1-TMX.