Radiographic contrast media alterate the localization of actin/band4.9 in the membrane cytoskeleton of human erythrocytes
Issue title: Selected Presentations held at the 33th Annual Conference of the German Society for Clinical Microcirculation and Hemorheology, Villingen-Schwenningen, Germany, 14-15 November, 2014
Affiliations: Department of Biomaterials, University of Ulm, Ulm, Germany | Institute for Biological Interfaces, Karlsruhe Institute of Technology (KIT) Karlsruhe, Germany | Institute for Heart and Circulation Research, Hamburg, Germany | Institute for Transplantation Diagnostics and Cell Therapeutics, Medical Center of University Düsseldorf, Germany | Institute of Biomaterial Science and Berlin-Brandenburg Center for Regenerative Therapies, Helmholtz-Zentrum Geesthacht, Berlin and Teltow, Germany
Note: [] Corresponding author: Dr. Friedrich Jung, Institute of Biomaterial Science and Berlin-Brandenburg Centre for Regenerative Therapies, Helmholtz-Zentrum Geesthacht, Berlin and Teltow, Germany. Tel.: +49 3328 352 269; E-mail: friedrich.jung@hzg.de
Abstract: Different radiographic contrast media (RCM) were shown to induce morphological changes of blood cells (e.g. erythrocytes or thrombocytes) and endothelial cells. The echinocytic shape change of erythrocytes, particularly, affords alterations of the membrane cytoskeleton. The cytoskeleton plays a crucial role for the shape and deformability of the red blood cell. Disruption of the interaction between components of the red blood cell membrane cytoskeleton may cause a loss of structural and functional integrity of the membrane. In this study band4.9 and actin as components of the cytoskeletal junctional complex were examined in human erythrocytes after suspension in autologous plasma or in plasma RCM mixtures (30% v/v Iodixanol-320 or Iopromide-370) followed by a successive double staining with TRITC-/FITC-coupled monoclonal antibodies. After adding Iopromide-370 to the plasma in practically none of the cells the rounded conformation of the membrane cytoskeleton – as it appeared in cells suspended in autologous plasma – was found. In addition, Iopromide-370 induced thin lines and coarse knob-like structures of band4.9 at the cell periphery while most cell centers were devoid of band4.9, and a box-like arrangement of bands of band4.9. A dissociation between colours red (actin) and green (band4.9) occurred as well. In contrast, erythrocytes suspended in a plasma/Iodixanol-320 mixture showed a membrane cytoskeleton comparable to cells suspended in autologous plasma, Similar results were found with respect to the distribution of actin. This study revealed for the first time RCM-dependent differences in band4.9 activities as possible pathophysiological mechanism for the chemotoxicity of radiographic contrast media.
