AA1704 OMVs were incubated with purified LtxA, untreated or pretreated with EGCg, for 15 mins at room temperature. OMV-associated and unbound LtxA were separated by SEC. One-mL fractions were collected, and the lipid concentration (white circles, primary y-axis) in each fraction was quantified using the FM 4–64 dye, and the LtxA concentration (black squares, secondary y-axis) was quantified using an immunoblot. (A) AA1704 OMVs incubated with untreated LtxA. (B) AA1704 OMVs incubated with EGCg-treated LtxA.