<p>Cell-to-cell adhesion assays involving the Caco-2 (<b>A</b>) and HT-29 (<b>B</b>) gut-related epithelial cell lines and the normalized (OD600 = 0.5) cultures of recombinant WT (GRS1189) and SpaF pilin-deleted (GRS1126) SpaFED-piliated lactococci, including GRS71 and GRS1052 cells as controls, were performed as outlined in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0113922#s4" target="_blank">Materials and Methods</a>. Triplicate measurements were taken for both sets of experiments. Caco-2 and HT-29 binding experiments were carried out independently four and three times, respectively. SEM is displayed as error bars. For both of the intestinal cell lines, pairwise comparisons made between GRS1189 or GRS1226 cells and the GRS71 control strain indicate the differences in binding data are statistically extremely significant (<i>P</i>≤0.0001).</p
