Biomechanical properties of red blood cells in health and disease towards microfluidics

Abstract

Red blood cells (RBCs) possess a unique capacity for undergoing cellular deformation to navigate across various human microcirculation vessels, enabling them to pass through capillaries that are smaller than their diameter and to carry out their role as gas carriers between blood and tissues. Since there is growing evidence that red blood cell deformability is impaired in some pathological conditions, measurement of RBC deformability has been the focus of numerous studies over the past decades. Nevertheless, reports on healthy and pathological RBCs are currently limited and, in many cases, are not expressed in terms of well-defined cell membrane parameters such as elasticity and viscosity. Hence, it is often difficult to integrate these results into the basic understanding of RBC behaviour, as well as into clinical applications. The aim of this review is to summarize currently available reports on RBC deformability and to highlight its association with various human diseases such as hereditary disorders (e.g., spherocytosis, elliptocytosis, ovalocytosis, and stomatocytosis), metabolic disorders (e.g., diabetes, hypercholesterolemia, obesity), adenosine triphosphate-induced membrane changes, oxidative stress, and paroxysmal nocturnal hemoglobinuria. Microfluidic techniques have been identified as the key to develop state-of-the-art dynamic experimental models for elucidating the significance of RBC membrane alterations in pathological conditions and the role that such alterations play in the microvasculature flow dynamics. V C 2014 AIP Publishing LLC.

Optically clear biomicroviscometer with modular geometry using disposable PDMS chips

“…Their biconcave shape, as shown in Figure 4 (a), allows for the ratio of surface area to volume to be high and also for the cell to be flexible [16], [17]. These cells deform in the capillaries to increase the surface contact area with the vessel walls, facilitating gas exchange.…”

“…Sickle cell disease causes the cells to have a reduced deformability due to abnormal sickle haemoglobin, which causes a cell to form with a sickle shape [21]. The RBCs are also known to deform due to being enriched in cholesterol, which causes the cells to become pancake-shaped with a wavy edge [17]. Since the viscosity depends on how the RBCs flow, the differentiation between normal and diseased RBCs is important.…”

“…hypercholesterolemia. In diabetes, the recovery time for a RBC to return to its original shape after being deformed is slowed, and cell deformability is additionally impaired [17]. Sickle cell disease causes the cells to have a reduced deformability due to abnormal sickle haemoglobin, which causes a cell to form with a sickle shape [21].…”

Automatic counting method for complex overlapping erythrocytes based on seed prediction in microscopic imaging

“…8 Traditional counting process, when performed manually, has been proved to be tedious, time consuming and subjective. Some automatic and accurate mechanisms are invented to cope with the aforementioned problems such as automatic°ow cytometry.…”

A counting method for complex overlapping erythrocytes-based microscopic imaging

“…Biconcave disk-shaped RBCs have dimensions of approximately 8 m in diameter and $2 m in thickness, through capillaries with diameters not more than 3-5 m, thus supplying oxygen to tissues of the body. 2 After blood smear being examined under microscope, the number of RBCs per unit volume can be counted. Counting process, when performed manually, have been proved to be tedious, time consuming and subjective.…”