Cytotoxicity of Environmentally Relevant Concentrations of Aluminum in Murine Thymocytes and Lymphocytes
Figure 4
Thymocytes were exposed to 0 μM (a, c) and 20 μM (b, d) AlCl3 at 0 and 20 minutes. Various staining patterns signify different cell populations. Region Q3 includes live cells (PI-negative and Annexin V-negative), whereas region Q4 contains apoptotic cells (PI-negative and Annexin V-positive). Dead cells are represented in Q2 region (both PI- and Annexin V-positive), while quadrant Q1 shows damaged cells (PI-positive and Annexin V-negative). Upon a 20-minute exposure to 20 μM AlCl3 the cell population from the Q3 region moved to Q1 region, without a clear shift to the Q4 area first. This fact indicates that thymocytes are not undergoing the apoptotic process. Contour plots (e, f) show fluorescence intensity with regard to forward scatter and side scatter in the control (e) and in the presence of 20 μM AlCl3 for 20 minutes (f). The increase in forward scatter on exposure to AlCl3 is indicative of an increase in size (i.e., swelling).
