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Controlled Microfluidic Environment for Dynamic Investigation of Red Blood Cell Aggregation
10:27

Controlled Microfluidic Environment for Dynamic Investigation of Red Blood Cell Aggregation

Published on: June 4, 2015

Translational mobility of the membrane intercalated particles of human erythrocyte ghosts. pH-dependent, reversible

P Pinto da Silva

    The Journal of Cell Biology
    |June 1, 1972
    PubMed

    Insights

    Human erythrocyte ghost membrane particles exhibit translational movement. Particle aggregation and disaggregation are pH-dependent, suggesting a fluid membrane model with mobile protein components.

    Area of Science:

    • Cell Biology
    • Membrane Biophysics

    Background:

    • The structure and dynamics of cell membranes are crucial for cellular function.
    • Erythrocyte membranes provide a model system for studying membrane properties due to their relative simplicity.

    Purpose of the Study:

    • To investigate the translational mobility of human erythrocyte ghost membrane particles.
    • To determine the effects of pH on membrane particle aggregation and disaggregation.

    Main Methods:

    • Freeze-fracture electron microscopy to visualize membrane particles.
    • Incubation of erythrocyte ghosts in media of varying pH (3.5, 4.5, 5.5, 9.5).
    • Assessment of particle aggregation and disaggregation under different ionic strengths and with glutaraldehyde prefixation.

    Main Results:

    • Demonstrated translational movement of membrane particles within the erythrocyte ghost plane.
    • Observed pH-dependent aggregation of particles around pH 5.5 and 3.5.
    • Noted particle disaggregation in neutral and alkaline conditions (pH 9.5) and at pH 4.5.
    • Found aggregation at pH 5.5 to be reversible, inhibited by glutaraldehyde and high ionic strength.
    • Particle aggregation occurred rapidly, within 2-4 minutes.

    Conclusions:

    • Erythrocyte ghost membranes behave as planar fluid domains.
    • The membrane is a bilayer continuum with localized, mobile protein intercalations.
    • pH plays a critical role in modulating the organization and mobility of membrane proteins.

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