FIG 3.

Sialic acids are required for LtxA-induced hemolysis. (A) Neuraminidase treatment of human erythrocytes decreases LtxA-induced hemolysis in a concentration-dependent manner. Values are normalized to a control without neuraminidase showing ∼50% lysis. (B) Neuraminidase treatment (60 mU ml⁻¹) of human erythrocytes reduces hemolysis at increasing concentrations of LtxA. (C) Neuraminidase treatment (60 mU ml⁻¹) of murine erythrocytes reduces hemolysis at increasing concentrations of LtxA. Bars display results from simultaneous experiments with human erythrocytes at an LtxA concentration of 10 μg ml⁻¹. (D) Neuraminidase treatment of rabbit erythrocytes only slightly inhibits LtxA-induced hemolysis.