FIG. 6.

Inhibition of E. coli invasion of HBMEC by Ecgp-Ab and Ecgp-Ab affinity-purified proteins. Confluent monolayers of HBMEC were incubated with either 10 μg (Ab-1) or 20 μg (Ab-2) of Ecgp-Ab or control antibody (C-Ab) for 1 h at 37°C prior to infection with the bacteria. In some experiments, Ecgp-Ab affinity-purified proteins from HBMEC (10 μg of Ab-affini-2), HUVEC (10 μg of Ab-HUVEC), CEC (10 μg of Ab-CEC), or BSA (10 μg) were incubated with E44 for 1 h on ice before adding to the HBMEC monolayers. Invasion assays were carried out as described in Materials and Methods. The experiments were carried out at least two times in triplicate and are expressed as a percentage of control with no protein (10,400 ± 2,000 CFU/well). The error bars represent the standard deviation. The inhibition of E. coli invasion by Ecgp-Ab and Ecgp-Ab affinity-purified proteins was statistically significant compared to the control (P < 0.05 by two-tailed, unpaired t test).