Journal des troubles sanguins et de la transfusion

Abstrait

Morphological Characteristics of Echinocytes: Novel Quantification of Spicule Geometry Using Scanning Electron Microscopy

Samantha Weber-Fishkin, Anna Eligulashvili, Lesley D Frame, Mary D Frame*

Healthy Red Blood Cells (RBCs) are biconcave discs, whose shape is mediated by the components of the erythroid membrane. Pathologic conditions that alter the fluidity of the membrane bilayer result in less deformable cells and, often, abnormal morphologies. Echinocytes are one such morphology characterized by dispersed spicules on the RBC surface. Our objectives are (1) to quantify the well-established qualitative descriptions of stage I, II, and III echinocytes, (2) to determine whether spicule size and symmetry are maintained within a stage of echinocytes, and (3) to determine whether disrupting specific cytoskeletal and transmembrane proteins will result in specific spicule morphologies in cold stored blood. RBCs obtained from healthy human donors were analyzed using optical brightfield and Scanning Electron Microscopy (SEM) imaging. Topology and topography measurements were made for characteristic spicules of RBCs treated with actin-destabilizing agents or agents that weakened the connection between the cytoskeleton and the membrane. Although topologic and topographic measurements within the clinical scoring of RBC morphology match, within each stage of echinocytes, there is non-uniform spicule arrangement and morphology. We show that spicule formation follows five, six or seven-fold symmetry, dependent on temperature, oxygen, and membrane or cytoskeleton stability.