Binding of Host Factors Influences Internalization and Intracellular Trafficking of Streptococcus uberis in Bovine Mammary Epithelial Cells
Figure 6
Scanning electron microscopy (SEM) of cocultures of bovine mammary epithelial cells with untreated S. uberis. Untreated Streptococcus uberis was cocultured with bovine mammary epithelial cells and observed using SEM at different incubation times (a)–(c). Upon contact with S. uberis (*) bovine mammary epithelial cells did not reacted abundantly as seen with S. uberis pretreated with fibronectin, collagen, or bovine lactoferrin. Although filopodia (white arrows) and flap-like structures (stripped arrows) were detected, these structures were also observed in MAC-T cells not cocultured with S. uberis (d). Even though cell membrane invaginations (black arrows) as well as S. uberis internalization (dot-filled arrows) were detected, neither flap-like structures engulfing bacteria nor filopodia sticking or covering S. uberis were observed.
