Fig. 8

Focal ion beam microscopy analysis of migration pathway of PMN and T-cells cells across the HIBCPP cells. Further analysis of the migration pathway of PMN and T-cells over uninfected and infected HIBCPP cell layers. Shown here are 3D images from HIBCPP + E-30 Bastianni + PMN + T-cells + IL8 (a, b) and HIBCPP + E-30 Bastianni + PMN + T-cells + CXCL12 (c, d). The first pair of images (a, b) shows a PMN moving paracellularly between choroid plexus epithelial cells (PE) and was taken from freeze-frames from Additional file 5. Clear intercellular gaps are visible around the periphery of the PMN and especially at the tricellular borders (arrowheads). The PMN is moving through the pore, into the HIBCPP layer, and in between HIBCPP cells. c, d Illustrate a transcellular migration of a T-cell across a HIBCPP cell with clear distance to any cell junction complex. These images were taken from freeze-frames from Additional file 8. Labelled are N = epithelial cell nucleus; PE = plexus epithelial cell, PMN = polymorphonuclear neutrophil