Figure 4

Analysis of cell permeabilization and cell death as a function of gas flow. (A) The cells were imaged on a fluorescent microscope after treatment with a helium gas jet exerting 0, 30, 65, 175, 290 and 390 Pa. Scale 150 μm. For this set of experiments, 500 μL of 120 μg / mL 10 kDa Texas Red dextran was used and a capillary diameter of 0.68 mm. The white box shows permeabilized live cells. Most of the cells in the 390 Pa image are dead. (B) From left to right, confocal image showing the fluorescence from the 10 kDa dextran molecules inside the HeLa the cells as a result of the helium gas jet treatment at 350 Pa (0.68 mm capillary diameter). Brightfield image of the same region, showing Trypan blue in the nucleus of a majority of cells which have died due to the treatment. Trypan blue is located in the nucleus of the cells, which appear darker as outlined by the white box. The composite image with the fluorescence and dead cell stain, indicates that a good number of living cells were permeabilized due to the treatment (box). Scale bars (A,B) 150 μm.