Investigating Electrophysiological Changes in Blood Cells Using Dielectrophoresis

Abstract

"The electrophysiological variation of RBCs and platelets is intriguing, as both are anucleate and lack traditional cellular apparatus; their behaviour is driven by the ion channels within the membrane. Assessment and characterisation of the electrophysiological rhythms of red blood cells (RBCs), and the observation of similar rhythms in platelets, is potentially of importance due to the temporal incidence of many diseases associated with these cell types. RBCs and platelets were examined using various methods including dielectrophoresis, flow cytometry, and zeta potential to assess for rhythmic properties.This work demonstrates that casein kinase is involved in RBC electrophysiological rhythms. Inhibition of casein kinase in RBCs altered the observed rhythm, revealing its involvement in both RBC electrophysiological rhythms and temperature compensation. The possible roles of intrinsic and extrinsic factors in RBC electrophysiological rhythms were examined. Levels of haemoglobin, ionic abundance, and passive electrophysiology were found to show time of day variation. Furthermore, zeta potential was used as a novel method to examine rhythmic electrophysiology.This thesis provides the first evidence of the presence of electrophysiological rhythms in platelets. Platelet electrophysiology was assessed in: platelet rich plasma immediately after venepuncture, stored platelet rich plasma, and stored resuspended platelets. Each condition exhibited a rhythm of differing period, suggesting the platelet entrainment mechanism involves at least three components: an intrinsic platelet component, entraining plasma component, and endogenous circulation component. Furthermore, activated platelets showed altered rhythms in each condition, suggesting the presence of an additional clock, functioning on platelet activation. The electrophysiological rhythm of a platelet precursor cell line was examined (in the assessment of the origin of platelet rhythms) and was found to be different to that of platelets.