Table 2.

Cytotoxicity of PE and its muteins on A549 and HepG2 cells. A549 and HepG2 cells were incubated with PE-native, PE-NLS, PE-furin and PE-Sigma (control protein) for 48 h. PE-inactive showed no cytotoxicity on both cell lines. The IC₅₀ values are representative of four experiments for each protein. * Statistically significant difference at p < 0.05.

Toxin	IC50 ± SD (ng/mL)
	A549	HepG2
PE-native	12 ± 4	22 ± 4 *
PE-inactive	-	-
PE-NLS	17 ± 6	13 ± 4
PE-furin	10 ± 1	13 ± 2
PE-Sigma	425 ± 65	3197 ± 1030 *