38 research outputs found
Biochemical and Biophysical Properties of Red Blood Cells in Disease
No full textRed blood cells (RBCs, erythrocytes) are highly specialized cells devoted to the transport of respiratory gases [...
Editorial : Red Blood Cell Vascular Adhesion and Deformability
No full textintroduction to a special issue in Frontiers in Physiology: Red Blood Cell PhysiologyInternational audienc
Circulatory Risk in the Transfusion of Red Blood Cells With Impaired Flow Properties Induced by Storage
No full textHemodynamic Functionality of Transfused Red Blood Cells in the Microcirculation of Blood Recipients
No full textThe primary goal of red blood cell (RBC) transfusion is to supply oxygen to tissues and organs. However, due to a growing number of studies that have reported negative transfusion outcomes, including reduced blood perfusion, there is rising concern about the risks in blood transfusion. RBC are characterized by unique flow-affecting properties, specifically adherence to blood vessel wall endothelium, cell deformability, and self-aggregability, which define their hemodynamic functionality (HF), namely their potential to affect blood circulation. The role of the HF of RBC in blood circulation, particularly the microcirculation, has been documented in numerous studies with animal models. These studies indicate that the HF of transfused RBC (TRBC) plays an important role in the transfusion outcome. However, studies with animal models must be interpreted with reservations, as animal physiology may not reflect human physiology. To test this concept in humans, we have directly examined the effect of the HF of TRBC, as expressed by their deformability and adherence to vascular endothelium, on the transfusion-induced effect on the skin blood flow and hemoglobin increment in β-thalassemia major patients. The results demonstrated, for the first time in humans, that the TRBC HF is a potent effector of the transfusion outcome, expressed by the transfusion-induced increase in the recipients' hemoglobin level, and the change in the skin blood flow, indicating a link between the microcirculation and the survival of TRBC in the recipients' vascular system. The implication of these findings for blood transfusion practice and to vascular function in blood recipients is discussed
Hemolytic Activity of Nanoparticles as a Marker of Their Hemocompatibility
No full textThe potential use of nanomaterials in medicine offers opportunities for novel therapeutic approaches to treating complex disorders. For that reason, a new branch of science, named nanotoxicology, which aims to study the dangerous effects of nanomaterials on human health and on the environment, has recently emerged. However, the toxicity and risk associated with nanomaterials are unclear or not completely understood. The development of an adequate experimental strategy for assessing the toxicity of nanomaterials may include a rapid/express method that will reliably, quickly, and cheaply make an initial assessment. One possibility is the characterization of the hemocompatibility of nanomaterials, which includes their hemolytic activity as a marker. In this review, we consider various factors affecting the hemolytic activity of nanomaterials and draw the reader’s attention to the fact that the formation of a protein corona around a nanoparticle can significantly change its interaction with the red cell. This leads us to suggest that the nanomaterial hemolytic activity in the buffer does not reflect the situation in the blood plasma. As a recommendation, we propose studying the hemocompatibility of nanomaterials under more physiologically relevant conditions, in the presence of plasma proteins in the medium and under mechanical stress
RBC Adhesion to Vascular Endothelial Cells: More Potent than RBC Aggregation in Inducing Circulatory Disorders
No full textMechanical Stimulation of Red Blood Cells Aging: Focusing on the Microfluidics Application
No full textHuman red blood cells (RBCs) are highly differentiated cells, essential in almost
all physiological processes. During their circulation in the bloodstream, RBCs are exposed
to varying levels of shear stress ranging from 0.1–10 Pa under physiological conditions to
50 Pa in arterial stenotic lesions. Moreover, the flow of blood through splenic red pulp and
through artificial organs is associated with brief exposure to even higher levels of shear
stress, reaching up to hundreds of Pa. As a result of this exposure, some properties of
the cytosol, the cytoskeleton, and the cell membrane may be significantly affected. In this
review, we aim to systematize the available information on RBC response to shear stress by
focusing on reported changes in various red cell properties. We pay special attention to the
results obtained using microfluidics, since these devices allow the researcher to accurately
simulate blood flow conditions in the capillaries and spleen
The Mechanical Properties of Erythrocytes Are Influenced by the Conformational State of Albumin
No full textThe mechanical stability and deformability of erythrocytes are vital for their function as they traverse capillaries, where shear stress can reach up to 10 Pa under physiological conditions. Human serum albumin (HSA) is known to help maintain erythrocyte stability by influencing cell shape, membrane integrity, and resistance to hemolysis. However, the precise mechanisms by which albumin exerts these effects remain debated, with some studies indicating a stabilizing role and others suggesting the opposite. This review highlights that under high shear rates, albumin molecules may undergo unfolding due to normal stress differences. Such structural changes can significantly alter albumin’s interactions with the erythrocyte membrane, thereby affecting cell mechanical stability. We discuss two potential scenarios explaining how albumin influences erythrocyte mechanics under shear stress, considering both the viscoelastic properties of blood and those of the erythrocyte membrane. Based on theoretical analyses and experimental evidence from the literature, we propose that albumin’s effect on erythrocyte mechanical stability depends on (i) the transition between unfolded and folded states of the protein and (ii) the impact of shear stress on the erythrocyte membrane’s ζ-potential. Understanding these factors is essential for elucidating the complex relationship between albumin and erythrocyte mechanics in physiological and pathological conditions
Human Red Blood Cell Shape and Volume are Changed by Physiological Levels of Hydrostatic Pressure
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