Toxicological Sciences

A color figure and a video supplemental to figure 1 of the print and online article. A video supplemental to figure 2 of the print and online article.

Files in this Data Supplement:

• Figure 1 (color) - Figure 1 (color): ECIS/taxis measurements of cell movement. A. Cells responding to a chemotactic gradient move in the direction of the arrow and ultimately cross the micro-electrode that is oriented perpendicular to the axis of cell movement. Crossing the electrode causes a change in current flow through the electrode that is recorded as an increased resistance. Higher resistance values correlate with greater coverage of the electrode by cells. B. Cells responding to a chemotactic gradient move in the direction of the arrow. In this configuration, the cells move along the long axis of the electrode, and cover increasing amounts of the electrode as they move further from the cell origin. C. Normalized resistance (Y-axis) is plotted against time (X-axis). Cells cultured in the absence of chemoattractant do not move to the electrode and thus do not alter the electrode resistance. Cells cultured in a gradient of activated complement, or in a gradient of leukotriene B4 (LTB4) display a vigorous response, and arrive at the target electrode. Cells pre-treated with an experimental LTB4 antagonist (CP105,696; generously provided by Pfizer, Inc.) display a dramatically diminished and slowed response to chemoattractant.
• Figure 1 video supplement - Figure 1 video supplement: Real-time resistance measurements paired with microscopic images. Images of cells crossing a target electrode can be found at by clicking on the link below. The cell well is off-screen at lower left and the cells are migrating along the chemotactic gradient. The inset figure represents normalized resistance at synchronized timepoints as the movie progresses.
• Figure 2 video supplement - Figure 2 video supplement: Please focus on the cell with the arrow (refer to Figure 2 in accompanying article to see the arrow). You will see that this cell makes attempts "protrusions" with its protopod into the opening. The protopod has the focus of the chemokine receptors. For unknown reasons, this cell choses not to migrate through this opening but moves to the left and goes through a different opening. This lead cell allows an attaching cell to be pulled through. It is suggested that the tail "uropod" of the lead cell has an increased concentration of adhesion molecules allowing another cell to attach and move through.