FIG. 1.

Preinfection of HEp-2 cells with EPEC or EHEC stimulates binding to immobilized MBP-intimin. HEp-2 cells were mock infected or infected with E. coli K-12 JM109, EPEC strain JPN15.96/pMAR7 (eae mutant) (A), or EHEC strain EDL933 (B). Bacteria were killed with gentamicin, and the HEp-2 cells were dispersed and added to microtiter wells coated with a control MBP fusion protein (β-gal), MBP-Int395 (Intimin) or MBP-Inv497 (Invasin). Bound cells were quantitated as previously described (20). Shown are representative results of two to six separate experiments. Binding to invasin was performed in a separate experiment in which JM109 preinfection (Preinf.) was omitted. Error bars indicate the standard deviations of quadruplicate samples. OD₅₇₀, optical density at 570 nm.