Impact of the membrane viscosity on the tank-treading behavior of red blood cells

AbstractDespite its demonstrated importance in the deformation and dynamics of red blood cells, membrane viscosity has not received the same attention in computational models as elasticity and bending stiffness. Recent experiments on red blood cells indicated a power law response due to membrane viscosity. This is potentially much different from the solid viscoelastic models, such as Kelvin-Voigt and standard linear solid (SLS), currently used in computation to describe this aspect of the membrane. Within the context of a framework based on lattice Boltzmann and immersed boundary methods, we introduce SLS and power law models for membrane viscosity. We compare how the Kelvin-Voigt (as approximated by SLS) and power law models alter the deformation and dynamics of a spherical capsule in shear flows.

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Influence of membrane viscosity on capsule dynamics in shear flow

Journal of Fluid Mechanics ◽

10.1017/jfm.2012.637 ◽

2013 ◽

Vol 718 ◽

pp. 569-595 ◽

Cited By ~ 62

Author(s):

Alireza Yazdani ◽

Prosenjit Bagchi

Keyword(s):

Shear Flow ◽

Red Blood Cells ◽

Blood Cells ◽

Viscoelastic Model ◽

Bending Stiffness ◽

Elastic Membrane ◽

Subsequent Increase ◽

Membrane Viscosity ◽

Monotonic Trend ◽

Capsule Dynamics

AbstractMost previous numerical studies on capsule dynamics in shear flow have ignored the role of membrane viscosity. Here we present a numerical method for large deformation of capsules using a Kelvin–Voigt viscoelastic model for the membrane. After introducing the model and the related numerical implementation, we present a comprehensive analysis of the influence of the membrane viscosity on buckling, deformation and dynamics. We observe that the membrane viscosity leads to buckling in the range of shear rate in which no buckling is observed for capsules with purely elastic membrane. For moderate to large shear rates, the wrinkles on the capsule surface appear in the same range of the membrane viscosity that was reported earlier for artificial capsules and red blood cells based on experimental measurements. In order to obtain stable shapes, it is necessary to introduce the bending stiffness. It is observed that the range of the bending stiffness required is also in the same range as that reported for the red blood cells, but considerably higher than that estimated for artificial capsules. Using the stable shapes obtained in the presence of bending stiffness, we analyse the influence of membrane viscosity on deformation, inclination and tank-treading frequency of initially spherical capsules. Membrane viscosity is observed to reduce the capsule deformation, and introduce a damped oscillation in time-dependent deformation and inclination. The time-averaged inclination angle shows a non-monotonic trend with an initial decrease reaching a minimum and a subsequent increase with increasing membrane viscosity. A similar non-monotonic trend is also observed in the tank-treading frequency. We then consider the influence of the membrane viscosity on the unsteady dynamics of an initially oblate capsule. The dynamics is observed to change from a swinging motion to a tumbling motion with increasing membrane viscosity. Further, a transient dynamics is also observed in which a capsule starts with one type of dynamics, but settles with a different dynamics over a long time.

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Hemoglobin crystals of the red blood cells in the human renal cortex: electron microscopic observations of the renal lithiasis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100083266 ◽

1978 ◽

Vol 36 (2) ◽

pp. 480-481

Author(s):

Kosuke Ueda ◽

Hiroto Washida ◽

Nakazo Watari

Keyword(s):

Red Blood Cells ◽

Blood Cells ◽

Renal Cortex ◽

Uranyl Acetate ◽

Osmic Acid ◽

Renal Lithiasis ◽

Electron Microscopic ◽

Hemoglobin C ◽

First Case ◽

Ultrathin Sections

IntroductionHemoglobin crystals in the red blood cells were electronmicroscopically reported by Fawcett in the cat myocardium. In the human, Lessin revealed crystal-containing cells in the periphral blood of hemoglobin C disease patients. We found the hemoglobin crystals and its agglutination in the erythrocytes in the renal cortex of the human renal lithiasis, and these patients had no hematological abnormalities or other diseases out of the renal lithiasis. Hemoglobin crystals in the human erythrocytes were confirmed to be the first case in the kidney.Material and MethodsTen cases of the human renal biopsies were performed on the operations of the seven pyelolithotomies and three ureterolithotomies. The each specimens were primarily fixed in cacodylate buffered 3. 0% glutaraldehyde and post fixed in osmic acid, dehydrated in graded concentrations of ethanol, and then embedded in Epon 812. Ultrathin sections, cut on LKB microtome, were doubly stained with uranyl acetate and lead citrate.

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Densitometric Identification of Primitive Erythroblasts After Reaction With Diaminobenzidine

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100072083 ◽

1973 ◽

Vol 31 ◽

pp. 328-329

Author(s):

John A. Trotter

Keyword(s):

Red Blood Cells ◽

Analytical Method ◽

Blood Cells ◽

Guinea Pigs ◽

Specific Protein ◽

Visual Examination ◽

Hemoglobin Synthesis ◽

Peroxidatic Activity ◽

Small Density

Hemoglobin is the specific protein of red blood cells. Those cells in which hemoglobin synthesis is initiated are the earliest cells that can presently be considered to be committed to erythropoiesis. In order to identify such early cells electron microscopically, we have made use of the peroxidatic activity of hemoglobin by reacting the marrow of erythropoietically stimulated guinea pigs with diaminobenzidine (DAB). The reaction product appeared as a diffuse and amorphous electron opacity throughout the cytoplasm of reactive cells. The detection of small density increases of such a diffuse nature required an analytical method more sensitive and reliable than the visual examination of micrographs. A procedure was therefore devised for the evaluation of micrographs (negatives) with a densitometer (Weston Photographic Analyzer).

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Scanning electron microscopy of erythrophagocytosis by Entamoeba histolytica trophozoites

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010012480x ◽

1992 ◽

Vol 50 (1) ◽

pp. 880-881

Author(s):

Victor Tsutsumi ◽

Adolfo Martinez-Palomo ◽

Kyuichi Tanikawa

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Red Blood Cells ◽

Entamoeba Histolytica ◽

Causative Agent ◽

Blood Cells ◽

Protozoan Parasite ◽

Complex Phenomenon ◽

Great Capacity ◽

Scanning Electron

The protozoan parasite Entamoeba histolytica is the causative agent of amebiasis in man. The trophozoite or motile form is a highly dynamic and pleomorphic cell with a great capacity to destroy tissues. Moreover, the parasite has the singular ability to phagocytize a variety of different live or death cells. Phagocytosis of red blood cells by E. histolytica trophozoites is a complex phenomenon related with amebic pathogenicity and nutrition.

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Ultrastructural observations on the in vitro cytoadherence of Plasmodium falciparum infected red blood cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100162132 ◽

1990 ◽

Vol 48 (3) ◽

pp. 914-915

Author(s):

D.J.P. Ferguson ◽

A.R. Berendt ◽

J. Tansey ◽

K. Marsh ◽

C.I. Newbold

Keyword(s):

Plasmodium Falciparum ◽

Red Blood Cells ◽

Blood Cells ◽

Umbilical Vein ◽

Cell Types ◽

Amelanotic Melanoma ◽

Cytoplasmic Process ◽

Umbilical Vein Endothelial Cells

In human malaria, the most serious clinical manifestation is cerebral malaria (CM) due to infection with Plasmodium falciparum. The pathology of CM is thought to relate to the fact that red blood cells containing mature forms of the parasite (PRBC) cytoadhere or sequester to post capillary venules of various tissues including the brain. This in vivo phenomenon has been studied in vitro by examining the cytoadherence of PRBCs to various cell types and purified proteins. To date, three Ijiost receptor molecules have been identified; CD36, ICAM-1 and thrombospondin. The specific changes in the PRBC membrane which mediate cytoadherence are less well understood, but they include the sub-membranous deposition of electron-dense material resulting in surface deformations called knobs. Knobs were thought to be essential for cytoadherence, lput recent work has shown that certain knob-negative (K-) lines can cytoadhere. In the present study, we have used electron microscopy to re-examine the interactions between K+ PRBCs and both C32 amelanotic melanoma cells and human umbilical vein endothelial cells (HUVEC).We confirm previous data demonstrating that C32 cells possess numerous microvilli which adhere to the PRBC, mainly via the knobs (Fig. 1). In contrast, the HUVEC were relatively smooth and the PRBCs appeared partially flattened onto the cell surface (Fig. 2). Furthermore, many of the PRBCs exhibited an invagination of the limiting membrane in the attachment zone, often containing a cytoplasmic process from the endothelial cell (Fig. 2).

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