Binding of Host Factors Influences Internalization and Intracellular Trafficking of Streptococcus uberis in Bovine Mammary Epithelial Cells

Figure 4

Transcytosis of Streptococcus uberis pretreated with host proteins across bovine mammary epithelial cells treated with the receptor mediated endocytosis inhibitor monodansylcadaverine detected at different incubation times. Fibronectin (FN), collagen (Coll), or bovine lactoferrin (LF) pre-treated S. uberis UT888 was cocultured with bovine mammary epithelial cells treated with the receptor-mediated endocytosis inhibitor monodansylcadaverine (MDC), and colony forming units per ml (cfu/mL) of S. uberis that transcytose bovine mammary epithelial cells were calculated at 60 (), 120 (), and 180 () min of incubation. Data are presented as the percentage of transcytosis through monodansylcadaverine treated bovine mammary epithelial cells (100%, 60 minutes = 5.1 $\times$ 10², 120 minutes = 6.3 $\times$ 10² ; 180 minutes = 1.0 $\times$ 10³) at each incubation time and bars represent the standard error of the mean of three independent experiments run in triplicate. (*) indicates statistically significant differences ($P<.05$) with the corresponding control. Means with similar superscript letters within each sampling time are statistically different ($P<.05$).