Investigation of cellular changes on blood cells relevant for the destabilization of blood flow

• Main Author: Stephanie.
• Other Authors: Bjoern Holger Neu
• Format: Final Year Project
• Language: English
• Published: 2009
• Subjects: DRNTU::Engineering::Chemical engineering::Biochemical engineering
• Online Access: http://hdl.handle.net/10356/16517
• Institution: Nanyang Technological University

Increased red blood cell adherence to endothelial cells has been found in diseases including sickle cell anemia, β-thalassaemia, diabetes mellitus, and malaria, in which red blood cells undergo various physicochemical changes on the membrane, leading to altered adhesion to endothelial cells. The current study mimicked these changes by using different enzyme treatments (neuraminidase, alpha-chymotrypsin, trypsin, and pronase) and investigated them by measuring zeta potential (surface charge) and deformability of treated cells as well as conducting gel electrophoresis. The adhesion was analyzed on a parallel plate flow chamber system. Zeta potential was increased after enzymatic treatments, with neuraminidase found to be the most effective in removing surface charge. Deformability was reduced in all enzyme-treated cells. Membrane composition changes were observed in all enzymes except neuraminidase. The presence of dextran, a macromolecule inducing depletion interaction used to mimic the impact of plasma, was found to significantly enhance the adhesion of both normal and enzyme-treated cells. In conclusion, depletion interaction is a significant determinant in red blood cell – endothelial cell adhesion, electrostatic repulsion is the key nonspecific force governing cell – cell interaction, and deformability reduction alters cell rheological properties which in turn reduce red blood cell – endothelial cell adhesion.