Induced Sickling of Erythrocytes Via Bending and the Effect of Mechanical Properties on Cell Pore Entry

Uzonwanne, Vanessa (2014-12-15)

Thesis

Patients living with sickle cell disease are perpetually plagued with painful crisis episodes, caused by vascular occlusion. Over time, this leads to oxygen deprivation and the eventual damage of starved tissues and organs. Observations stemming from mechanical characterization of both diseased and healthy red blood cells (RBC), establish that shape and mechanical properties of human red blood cells are essential in maintaining normal functionality of these cells. From a molecular biology stand point the sickling process has been mapped out yet there is a gap in the actual mode of deformation that results in the characteristic sickle or crescent shape observed experimentally. As a consequence, this research proposes that bending forces imposed by internal RBC structures are a possible culprit and utilizes AbaqusTM software to model the sickling of an erythrocyte with sickle cell traits under bending conditions. Critical Pressure value required for cell pore aspiration of a normal erythrocyte, oxygenated and deoxygenated sickle cell are also estimated for their respective moduli. It was found that bending could cause morphological sickling but the model did not account for change in modulus upon deformation. Critical Pressure value increased from normal, to oxygenated and then to deoxygenated sickle cell which tally’s with the trend in decreasing Aspiration ratio calculated.