Effect of spectrin network elasticity on the shapes of erythrocyte doublets

Red blood cells (RBCs) in plasma or polymer solution interact attractively to form various shapes of RBC doublets. A rich variety of doublet shapes is found, depending on membrane shear and bending elasticity, reduced volumes, and adhesion strength.

Download Full-text

The steady motion of a closely fitting vesicle in a tube

Journal of Fluid Mechanics ◽

10.1017/jfm.2017.743 ◽

2017 ◽

Vol 835 ◽

pp. 721-761 ◽

Cited By ~ 9

Author(s):

Joseph M. Barakat ◽

Eric S. G. Shaqfeh

Keyword(s):

Red Blood Cells ◽

Blood Cells ◽

Steady Motion ◽

Bending Stiffness ◽

Singular Perturbation Theory ◽

Bending Elasticity ◽

Theoretical Predictions ◽

Bending Stresses ◽

Membrane Bending ◽

Lipid Bilayer Vesicle

A singular perturbation theory is developed for the steady, inertialess motion of a lipid-bilayer vesicle flowing through a narrow tube. The vesicle is treated as a sac of fluid enclosed by an inextensible membrane that admits a bending stiffness. Matched asymptotic expansions are developed in terms of a clearance parameter $\unicode[STIX]{x1D716}\ll 1$ in order to calculate the flow field and vesicle shape. Mild restrictions are applied to the ratio of viscosities $\unicode[STIX]{x1D705}$ and the ratio of bending stresses to viscous stresses $\unicode[STIX]{x1D6FD}$; in particular, the theory holds for $\unicode[STIX]{x1D705}=o(\unicode[STIX]{x1D716}^{-1/2})$ and $\unicode[STIX]{x1D6FD}=O(\unicode[STIX]{x1D716}^{-1})$. The ratio of the vesicle length to the tube radius $\ell$ is included as a parameter and asymptotic solutions in the limit of negligible bending stiffness are developed for long, cylindrical vesicles and short, spherical vesicles. The main result of the theory is a prediction for the vesicle speed and extra pressure drop due to the presence of the vesicle in the tube. The effects of confinement, vesicle length, and membrane bending elasticity are examined. The theoretical predictions show good agreement with experimental measurements reported for vesicles and red blood cells in highly confined channel flow. Previously reported models for red blood cells (Secomb et al., J. Fluid Mech., vol. 163, 1986, pp. 405–423; Halpern & Secomb, J. Fluid Mech., vol. 203, 1989, pp. 381–400) are clarified and extended in light of the new theory.

Download Full-text

Influence of the spectrin network on fusion of influenza virus with red blood cells

Molecular Membrane Biology ◽

10.3109/09687689509072427 ◽

1995 ◽

Vol 12 (3) ◽

pp. 271-276 ◽

Cited By ~ 1

Author(s):

Torsten Reda ◽

Robert Blumenthal ◽

Peter Müller ◽

Andreas Herrmann

Keyword(s):

Influenza Virus ◽

Red Blood Cells ◽

Blood Cells ◽

Spectrin Network

Download Full-text

Entropic elasticity of end adsorbed polymer chains: The spectrin network of red blood cells asC*‐gel

The Journal of Chemical Physics ◽

10.1063/1.471539 ◽

1996 ◽

Vol 104 (10) ◽

pp. 3774-3781 ◽

Cited By ~ 7

Author(s):

Ralf Everaers ◽

Ian S. Graham ◽

Martin J. Zuckermann ◽

Erich Sackmann

Keyword(s):

Red Blood Cells ◽

Blood Cells ◽

Polymer Chains ◽

Entropic Elasticity ◽

Adsorbed Polymer ◽

Spectrin Network

Download Full-text

Red Blood Cells from Alzheimer Patients and from Normal Subjects Discerned by Cell Electrophoresis in an Aqueous Polymer Solution

Biochemical and Biophysical Research Communications ◽

10.1006/bbrc.1993.1779 ◽

1993 ◽

Vol 194 (1) ◽

pp. 23-28 ◽

Cited By ~ 5

Author(s):

H. Walter ◽

K.E. Widen ◽

S.L. Read

Keyword(s):

Red Blood Cells ◽

Polymer Solution ◽

Blood Cells ◽

Normal Subjects ◽

Cell Electrophoresis ◽

Aqueous Polymer ◽

Aqueous Polymer Solution

Download Full-text

Motion of red blood cells in a capillary with an endothelial surface layer: effect of flow velocity

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.2001.281.2.h629 ◽

2001 ◽

Vol 281 (2) ◽

pp. H629-H636 ◽

Cited By ~ 92

Author(s):

T. W. Secomb ◽

R. Hsu ◽

A. R. Pries

Keyword(s):

Surface Layer ◽

Red Blood Cells ◽

Flow Velocity ◽

Plasma Flow ◽

Blood Cells ◽

Axisymmetric Deformation ◽

Endothelial Surface Layer ◽

Bending Elasticity ◽

Endothelial Surface ◽

Layer Effect

Interior surfaces of capillaries are lined with macromolecules forming an endothelial surface layer (ESL). A theoretical model is used to investigate effects of flow velocity on motion and axisymmetric deformation of red blood cells in a capillary with an ESL. Cell deformation is analyzed, including effects of membrane shear and bending elasticity. Plasma flow around the cell and through the ESL is computed using lubrication theory. The ESL is represented as a porous layer that exerts compressive forces on red blood cells that penetrate it. According to the model, hydrodynamic pressures generated by plasma flow around the cell squeeze moving red blood cells into narrow elongated shapes. If the ESL is 0.7 μm wide, with hydraulic resistivity of 2 × 108dyn · s · cm−4, and exerts a force of 20 dyn/cm2, predicted variation with flow velocity of the gap width between red blood cell and capillary wall agrees well with observations. Predicted gap at a velocity of 0.1 mm/s is ∼0.6 μm vs. ∼0.2 μm with no ESL. Predicted flow resistance increases markedly at low velocities. The model shows that exclusion of red blood cells from the ESL in flowing capillaries can result from hydrodynamic forces generated by plasma flow through the ESL.

Download Full-text

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.

Download Full-text

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).

Download Full-text

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.

Download Full-text

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).

Download Full-text