Figure 6.

Inhibition of the binding of protective antigen (PA) to RAW264.7 cells by preincubation of toxin with monoclonal antibodies. PA at a concentration of 6 nmol/L (500 ng/mL) was incubated with anti-PA 14B7 or W2 antibodies at a molar ratio of 1:1 or 1:10 for 5 min. The mixture was added to RAW264.7 cells and was incubated for 20 min at 37°C. After the cells were washed and lysed, separation by SDS-PAGE was performed. The proteins were transferred to a membrane and were probed with anti-PA polyclonal antibody