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Updated: Aug 30, 2026
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Ex Vivo Red Blood Cell Hemolysis Assay for the Evaluation of pH-responsive Endosomolytic Agents for Cytosolic Delivery of Biomacromolecular Drugs
Published on: March 9, 2013
Membrane-active agents and heat-induced erythrocyte fragmentation
British Journal of Haematology
|February 1, 1982
Abstract:
Morphological observations of heated erythrocytes were made after preincubation with lysolecithin, diamide, p-chloromercuribenzoate, or N-ethyl maleimide and after ATP-depletion. Diamide (1.0 mM) reduced the critical temperature of fragmentation from 49 degrees C to 47 degrees C, and at higher concentrations the critical temperature was further reduced. The other sulphydryl reacting agents had little or no effect. Drug-induced spherocytes and ATP-depleted cells did not fragment. Membrane-active agents can effect the response of membranes to heat and the effect is dose-dependent.
Insights
Diamide treatment lowers the heat at which erythrocytes fragment, while other agents and ATP-depletion do not. Membrane-active agents influence heat response in a dose-dependent manner.
Area of Science:
- Cell biology
- Biochemistry
- Membrane biophysics
Background:
- Erythrocytes (red blood cells) undergo morphological changes when exposed to heat.
- The integrity of the erythrocyte membrane is crucial for cell survival and function.
- Sulfhydryl groups in membrane proteins play a role in maintaining membrane structure.
Purpose of the Study:
- To investigate the effect of specific chemical agents on the thermal stability of erythrocyte membranes.
- To determine how alterations in cellular energy levels (ATP-depletion) impact heat-induced erythrocyte fragmentation.
- To elucidate the role of sulfhydryl reactivity in erythrocyte thermal response.
Main Methods:
- Erythrocytes were preincubated with lysolecithin, diamide, p-chloromercuribenzoate, or N-ethyl maleimide.
- Erythrocytes were subjected to ATP-depletion.
- Morphological observations of heated erythrocytes were conducted to determine the critical fragmentation temperature.
- Dose-response effects of diamide were analyzed.
Main Results:
- Diamide significantly reduced the critical fragmentation temperature of erythrocytes in a dose-dependent manner.
- Other sulfhydryl-reactive agents (p-chloromercuribenzoate, N-ethyl maleimide) showed minimal to no effect on thermal stability.
- ATP-depleted erythrocytes and drug-induced spherocytes did not exhibit fragmentation upon heating.
- Membrane-active agents demonstrably alter the heat response of erythrocyte membranes.
Conclusions:
- Diamide's effect on erythrocyte thermal stability is linked to its specific chemical properties, potentially involving sulfhydryl interactions.
- The findings highlight that not all sulfhydryl-reactive agents impact erythrocyte heat response equally.
- Cellular energy status and membrane integrity are critical factors in preventing heat-induced erythrocyte fragmentation.
- Membrane-active agents can modulate erythrocyte thermotolerance, with effects being concentration-dependent.
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