Figure 8.

Pretreatment with probiotics prevents epidermal growth factor receptor (EGFr) inactivation by enteroinvasive Escherichia coli (EIEC). HT29/cl.19A cell monolayers were exposed to medium, Streptococcus thermophilus and Lactobacillus acidophilus (ST/LA), EIEC, or ST/LA followed by EIEC. Both living and antibiotic killed (^a) ST and LA were tested in these experiments. Before harvest at three hours after infection, cells were treated with EGF (50 nM, two minutes) or medium alone. After lysis and immunoprecipitation with anti-EGFr, proteins were electrophoresed and blotted with the same antibody or with antiphosphotyrosine. The top panel shows representative blots whereas the bottom panel shows means (SEM) for densitometric analyses, n=6. ***p<0.001 compared with uninfected cells stimulated with EGF (by ANOVA) (n=4, means (SEM)).