Figure 5
From: A Simulated Microgravity Environment Causes a Sustained Defect in Epithelial Barrier Function
Susceptibility to acetaldehyde induction of barrier defects is specific to the simulated microgravity condition. (A) HT-29.cl19a IECs were cultured as microcarrier bead-cell aggregates under established RWV conditions or in a ‘Biowiggler’. Cell-bead aggregate formation was sampled at day 12 and visualized under phase-contrast microscopy. (B) Immunofluorescence imaging shows bead coverage by IECs and formation of cell junctions as shown by actin staining (red). Nuclei were stained with DAPI (blue). (C) Cells were removed from beads or a control flask and cultured on semi-permeable supports (transwells) for 11 days. TER was recorded immediately prior to exposure of cells from each condition to acetaldehyde vapor (5hrs), and the change in TER caused by acetaldehyde was calculated and expressed as the % change in TER from t0 to t5hr. Cells originally cultured in the RWV, but not the Biowiggler, showed a significantly greater decrease in TER from control flask conditions (*p < 0.05 vs. Flask + acetaldehyde condition; n = 3). (D) After 5 hrs of acetaldehyde vapor exposure, permeability to FD4 (over 1 hr) was measured and found to be significantly elevated in cells from the RWV, but not the Biowiggler compared with control cells. Data are expressed as fold change in FD4 permeability (*p < 0.05 vs. Flask + acetaldehyde condition; n = 3).
