Figure 1. Cytotoxicity of ricin. A, Kinetics of cell growth (cell concentration estimated by cell counting) after treatment with PBS (pH 7.0, control), 1 µg/mL ricin and 1 µg/mL ricin plus anti-ricin antibody (IgG). B, Microscopy of cell cultures 48 h after treatment. Vero cells (arrow) loose spread distribution and compact monolayer architecture (bar = 50 µm). C, Cytotoxicity measured using a lactate dehydrogenase assay (positive control: 2% Triton).
