(19e) Identification of Rigid Red Blood Cell Population Rigidity in Sickle-Cell Disease Patients Using a Parameterization Model of Ektacytometry
Here, we present an approach to estimate rigidity of HbS cells, i.e. rigid RBCs, in SCD via the artificial rigidification of healthy RBCs at different degrees of stiffnesses which are then mixed into whole blood samples with different fractions of healthy soft RBCs. Healthy donor, i.e. non-SCD donor, RBCs are incubated with predetermined concentrations of tert-butly hydroperoxide to induce RBC membrane rigidification. Whole blood samples with controlled amounts of rigid RBCs are measured via ektacytometry. We then parameterize these ektacytometry measurements to develop a method that predicts the bulk rigidity of the rigid RBC population in a SCD patient blood sample. Using hemoglobin electrophoresis, we determine rigid fraction of rigid RBCs in SCD patient blood samples. We find that bulk ektactymoetry measurements typically underestimate the stiffness of rigid RBCs. In some SCD patients, the stiffness of rigid RBCs is often underestimated by ~4 times fold when compared to a bulk ektacytometry measurement.
This novel method can estimate bulk rigidity of rigid RBC populations with greater certainty, which can serve as a potential platform for more accurately estimating rigidity of rigid RBC populations in a patient sample and thus better understanding disease severity in a patient and deciding optimal treatment options.