Figure 4. Bovine CE monolayers on EBMs have continuous ZO-1 expression and remodel the ECM layer of the EBM.

Representative confocal microscopy images after weeks 1 (a) and 4 (b) in culture. (a) At week 1, the F-actin cytoskeletal structure on all 3 sample types is unorganized with more F-actin stress fibers across the cell bodies. Bovine CE cells monolayers on the EBM have more continuous ZO-1 present at the borders of the cells, whereas bovine CE cells on both control samples have very little ZO-1 present. On the EBM, the original labeled COL4 is still present, showing the cells have not completely remodeled the EBM, but the LAM structure is different from the original ECM sheet, showing the cells are remodeling the ECM or laying down their own matrix. Similarly, LAM is present on COL1and COL1+gelatin. (b) By 4 weeks, the F-actin stress fibers of cells on all sample types are more organized and located cortically. Bovine CE cells on the EBM express continuous ZO-1at the borders resembling CE cells in vivo. In contrast, cells on the COL1 and COL1+gelatin have much less and non-continuous ZO-1. The LAM structure on all 3 samples is different from that at week 1, indicating the cells are remodeling the matrix they have begun to assemble. The original labeled COL4 is still present on the EBM.