A microscopic image of piglet ileal section to show colonization of <i>E. coli</i> strain 8321 that expresses EAST1 toxin.

<p>Ileal segments of piglets challenged with strain 8321 were collected at necropsy and fixed at 10% neutral buffered Formalin. Fixed tissues were embedded, sectioned, H&E stained, and examined microscopically using an Olympus IX70 inverted microscope.</p

Intracellular cyclic AMP and GMP levels (pmole/ml) in T-84 cells incubated with culture supernatant of strains 8724 (EAST1/LT), 8607 (LT), 8725 (EAST1/STa), 8295 (STa), 17-2 (EAST1), or cell culture medium, measured using cAMP or cGMP EIA kits (Assay Design).

*<p>A non-acetylated version analysis was used to measure cAMP or cGMP concentrations in initial assays. ND indicates not done.</p

<i>E. coli</i> strains and plasmids used in this study.

<p><i>E. coli</i> strains and plasmids used in this study.</p

EAST1 competitive ELISA to detect EAST1protein expressed from the recombinant strains.

<p>10 ng EAST1-ovalbumin conjugates were coated at each well of a microtiter plate at 37°C overnight. 75 µl supernatants of overnight grown culture, from an equal amount of cells, of each strain, and 75 µl of chicken anti-EAST1 serum (1∶1000; GenWay Biotech, Inc., CA) was mixed and added to each well. HRP-conjugated donkey anti-chicken IgY (1∶2500; GenWay Biotech, Inc., CA) was used as the secondary antibody. OD values were measured at 405 nm after 20 min incubation with peroxidase substrate.</p