Group BStreptococcusCrosses Human Epithelial Cells by a Paracellular Route

Abstract

Colonization of the colon and vagina is thought to be important in the pathogenesis of group B Streptococcus (GBS) infection. However, little is known about the strategies used by GBS to translocate through the epithelial barrier during the onset of disease. We used differentiated epithelial cells grown on transwell inserts as a model of the epithelial barrier. Bacterial translocation occurred without a detectable decrease in transepithelial resistance. Whereas acapsular GBS was better able to adhere to and invade epithelial cells, the percentage of bacteria translocating across the epithelial monolayer was independent of the presence of the capsule. Transmission electron microscopy showed the intimate association of GBS with intercellular junctions and the capacity to cross the monolayer by a paracellular mechanism. This process consisted of an active and transient opening of cell junctions. Indeed, GBS was preferentially found along the cell perimeter, where it colocalized with junctional protein complexes.

Association and Virulence Gene Expression Vary among Serotype III Group B Streptococcus Isolates following Exposure to Decidual and Lung Epithelial Cells

“…In a previous study using electron microscopy, Soriani et al found that GBS strains use a paracellular route to cross cervical epithelial cells. The majority of GBS were found in the spaces between the cells, with very few passing through the cells themselves (30). Therefore, variation in invasive ability among GBS strains needs to be further tested using other assays that account for the paracellular route of invasion as well.…”

Identification of the Actin and Plasminogen Binding Regions of Group B Streptococcal Phosphoglycerate Kinase

“…Plasminogen recruitment has been demonstrated to contribute to bacterial virulence through mediating adhesion to host cells (41,60,61). In addition, activation of the recruited plasminogen to plasmin has been demonstrated to play a role in the breakdown of extracellular matrix proteins (41)(42)(43)(44) and may contribute to GBS paracellular invasion (62). Initial experiments demonstrated that GBS encodes several plasminogen binding proteins, one of which was identified as GAPDH (43).…”

Transcellular Passage of Neisseria meningitidis across a Polarized Respiratory Epithelium

“…There is a distinction between pathogens that utilize a transcellular route to cross epithelial cell monolayers (19) and bacteria that cross by a paracellular route after destruction of cells of the layer or disruption of tight junctions (1,10,18,34,35,40,55,59,68). There is conflicting evidence about the route that the meningococcus takes to traverse the epithelial cell barrier in the nasopharynx.…”