scholarly journals Spherization of red blood cells and platelets margination in COPD patients

2020 ◽  
Author(s):  
Karim Zouaoui Boudjeltia ◽  
Christos Kotsalos ◽  
Daniel Ribeiro ◽  
Alexandre Rousseau ◽  
Christophe Lelubre ◽  
...  
Keyword(s):  
Shear Rate ◽  
Numerical Simulations ◽  
Red Blood Cells ◽  
Conformational Changes ◽  
Blood Cells ◽  
Mean Square Displacement ◽  
Neuraminidase Treatment ◽  
Copd Patients ◽  
Platelet Aggregates

AbstractRationaleThere are important interactions between Red Blood Cells (RBCs) and platelets in the bloodstream. These interactions lead to a phenomenon called margination. RBCs in pathological situations undergo biochemical and conformational changes leading to alterations in blood rheology.AimRBCs shape in volunteers (21), stable (42) and exacerbated (31) COPD patients was analyzed. We studied the effect of the RBCs spherization on the platelets transport experimentally, in vitro, and by using numerical simulations.MethodsRBC shape was estimated by the second moment of Pearson obtained through flow cytometry on fsc histogram. In vitro experiments were performed to analyze the effect of RBC shape on platelets adhesion/aggregation in dynamic conditions. Neuraminidase treatment was used to induce RBCs spherization. Numerical simulation were performed to determine the effect of RBCs spherization on platelets mean square displacement (MSD) to provide a physical explanation.ResultsSignificant increase of RBC sphericity was observed in COPD patients compared to volunteers (Kruskal-Wallis: p<0.0001). In vitro experiments, at shear rate of 100 s-1, we observed that RBCs treated with neuraminidase mainly affect the number of platelet aggregates (p = 0.004). There was no change in the aggregates size. At a shear rate of 400 sec-1 neuraminidase treatment changes both the size of the aggregates (p = 0.009) and the number of platelet aggregates (p = 0.008).Numerical simulations indicated that RBCs spherization induces an increase of MSD and the effect was more pronounced when the shear rate increased.ConclusionOur results show that the RBCs of COPD patients are more spherical than those of healthy volunteers. Experimentally we observe that the RBCs spherization induces an increase platelet transport to the wall. Additional studies are needed to better understand the possible association between the RBCs effect on the platelets transport and the increased cardiovascular events observed in COPD patients.

Effect of aggregation and shear rate on the dispersion of red blood cells flowing in venules

2002 ◽  
Vol 283 (5) ◽  
pp. H1985-H1996 ◽  
Author(s):  
Jeffrey J. Bishop ◽  
Aleksander S. Popel ◽  
Marcos Intaglietta ◽  
Paul C. Johnson
Keyword(s):  
Shear Rate ◽  
Blood Cell ◽  
Red Blood Cells ◽  
Red Blood Cell ◽  
Blood Cells ◽  
Cell Aggregation ◽  
Radial Position ◽  
Red Blood Cell Aggregation ◽  
Blood Cell Aggregation

Previous in vitro studies of blood flow in small glass tubes have shown that red blood cells exhibit significant erratic deviations in the radial position in the laminar flow regime. The purpose of the present study was to assess the magnitude of this variability and that of velocity in vivo and the effect of red blood cell aggregation and shear rate upon them. With the use of a gated image intensifier and fluorescently labeled red blood cells in tracer quantities, we obtained multiple measurements of red blood cell radial and longitudinal positions at time intervals as short as 5 ms within single venous microvessels (diameter range 45–75 μm) of the rat spinotrapezius muscle. For nonaggregating red blood cells in the velocity range of 0.3–14 mm/s, the mean coefficient of variation of velocity was 16.9 ± 10.5% and the SD of the radial position was 1.98 ± 0.98 μm. Both quantities were inversely related to shear rate, and the former was significantly lowered on induction of red blood cell aggregation by the addition of Dextran 500 to the blood. The shear-induced random movements observed in this study may increase the radial transport of particles and solutes within the bloodstream by orders of magnitude.

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

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).

The Effect of Red Blood Cells on the ADP-induced Aggregation of Human Platelets in Flow Through Tubes

1990 ◽  
Vol 63 (01) ◽  
pp. 112-121 ◽  
Author(s):  
David N Bell ◽  
Samira Spain ◽  
Harry L Goldsmith
Keyword(s):  
Platelet Aggregation ◽  
Shear Rate ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Platelet Rich Plasma ◽  
Mean Transit Time ◽  
White Blood Cells ◽  
Aggregate Size ◽  
Human Platelets ◽  
Induced Aggregation

SummaryThe effect of red blood cells, rbc, and shear rate on the ADPinduced aggregation of platelets in whole blood, WB, flowing through polyethylene tubing was studied using a previously described technique (1). Effluent WB was collected into 0.5% glutaraldehyde and the red blood cells removed by centrifugation through Percoll. At 23°C the rate of single platelet aggregtion was upt to 9× greater in WB than previously found in platelet-rich plasma (2) at mean tube shear rates Ḡ = 41.9,335, and 1,920 s−1, and at both 0.2 and 1.0 µM ADP. At 0.2 pM ADP, the rate of aggregation was greatest at Ḡ = 41.9 s−1 over the first 1.7 s mean transit time through the flow tube, t, but decreased steadily with time. At Ḡ ≥335 s−1 the rate of aggregation increased between t = 1.7 and 8.6 s; however, aggregate size decreased with increasing shear rate. At 1.0 µM ADP, the initial rate of single platelet aggregation was still highest at Ḡ = 41.9 s1 where large aggregates up to several millimeters in diameter containing rbc formed by t = 43 s. At this ADP concentration, aggregate size was still limited at Ḡ ≥335 s−1 but the rate of single platelet aggregation was markedly greater than at 0.2 pM ADP. By t = 43 s, no single platelets remained and rbc were not incorporated into aggregates. Although aggregate size increased slowly, large aggregates eventually formed. White blood cells were not significantly incorporated into aggregates at any shear rate or ADP concentration. Since the present technique did not induce platelet thromboxane A2 formation or cause cell lysis, these experiments provide evidence for a purely mechanical effect of rbc in augmenting platelet aggregation in WB.

The Ullrastructure of Platelet Participation in Hemostasis

1965 ◽  
Vol 13 (01) ◽  
pp. 065-083 ◽  
Author(s):  
Shirley A. Johnson ◽  
Ronaldo S. Balboa ◽  
Harlan J. Pederson ◽  
Monica Buckley
Keyword(s):  
Platelet Aggregation ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Guinea Pigs ◽  
Platelet Factor ◽  
Mesenteric Vessels ◽  
Platelet Aggregates ◽  
Electron Lucent

SummaryThe ultrastructure of platelet aggregation in vivo in response to bleeding brought about by transection of small mesenteric vessels in rats and guinea pigs has been studied. Platelets aggregate, degranulate and separating membranes disappear in parallel with fibrin appearance which is first seen at several loci after 30 seconds of bleeding. About 40 per cent of the electron opaque granules, some of which contain platelet factor 3 have disappeared after one minute of bleeding while the electron lucent granules increase by 70 per cent suggesting that some of them may be empty vesicles. Most of the platelet aggregates of the random type disappear leaving clumped red blood cells entrapped by a network of fibrin fibers which emanate from the remains of platelet aggregates of the rosette type to maintain hemostasis.

Effect of liposomal curcumin on red blood cells in vitro

2013 ◽  
Vol 1 (Suppl. 1) ◽  
pp. A4.1
Author(s):  
Angela Storka
Keyword(s):  
Red Blood Cells ◽  
Blood Cells

scholarly journals THE SYNTHESIS OF PROTOPORPHYRIN IN VITRO BY RED BLOOD CELLS OF THE DUCK

1950 ◽  
Vol 183 (2) ◽  
pp. 757-765 ◽  
Author(s):  
David Shemin ◽  
Irving M. London ◽  
D. Rittenberg
Keyword(s):  
Red Blood Cells ◽  
Blood Cells

Nucleated red blood cells participate in myocardial regeneration in the toad Bufo Gargarizan Gargarizan

2021 ◽  
pp. 153537022110132
Author(s):  
Shu-Qin Liu ◽  
Xiao-Ye Hou ◽  
Feng Zhao ◽  
Xiao-Ge Zhao
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Cardiac Injury ◽  
Myocardial Regeneration ◽  
Matrix Metalloproteinase 2 ◽  
Enzyme Linked Immunosorbent Assay ◽  
Cardiac Tissues ◽  
Nucleated Red Blood Cells ◽  
Model Animal

Heart regeneration is negligible in humans and mammals but remarkable in some ectotherms. Humans and mammals lack nucleated red blood cells (NRBCs), while ectotherms have sufficient NRBCs. This study used Bufo gargarizan gargarizan, a Chinese toad subspecies, as a model animal to verify our hypothesis that NRBCs participate in myocardial regeneration. NRBC infiltration into myocardium was seen in the healthy toad hearts. Heart needle-injury was used as an enlarged model of physiological cardiomyocyte loss. It recovered quickly and scarlessly. NRBC infiltration increased during the recovery. Transwell assay was done to in vitro explore effects of myocardial injury on NRBCs. In the transwell system, NRBCs could infiltrate into cardiac pieces and could transdifferentiate toward cardiomyocytes. Heart apex cautery caused approximately 5% of the ventricle to be injured to varying degrees. In the mildly to moderately injured regions, NRBC infiltration increased and myocardial regeneration started soon after the inflammatory response; the severely damaged region underwent inflammation, scarring, and vascularity before NRBC infiltration and myocardial regeneration, and recovered scarlessly in four months. NRBCs were seen in the newly formed myocardium. Enzyme-linked immunosorbent assay and Western blotting showed that the levels of tumor necrosis factor-α, interleukin- 1β, 6, and11, cardiotrophin-1, vascular endothelial growth factor, erythropoietin, matrix metalloproteinase- 2 and 9 in the serum and/or cardiac tissues fluctuated in different patterns during the cardiac injury-regeneration. Cardiotrophin-1 could induce toad NRBC transdifferentiation toward cardiomyocytes in vitro. Taken together, the results suggest that the NRBC is a cell source for cardiomyocyte renewal/regeneration in the toad; cardiomyocyte loss triggers a series of biological processes, facilitating NRBC infiltration and transition to cardiomyocytes. This finding may guide a new direction for improving human myocardial regeneration.

scholarly journals Multimodal Diagnostics of Microrheologic Alterations in Blood of Coronary Heart Disease and Diabetic Patients

Diagnostics ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 76
Author(s):  
Anastasia Maslianitsyna ◽  
Petr Ermolinskiy ◽  
Andrei Lugovtsov ◽  
Alexandra Pigurenko ◽  
Maria Sasonko ◽  
...  
Keyword(s):  
Coronary Heart Disease ◽  
Heart Disease ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Optical Methods ◽  
Diabetic Patients ◽  
Aggregation Index ◽  
Significant Difference

Coronary heart disease (CHD) has serious implications for human health and needs to be diagnosed as early as possible. In this article in vivo and in vitro optical methods are used to study blood properties related to the aggregation of red blood cells in patients with CHD and comorbidities such as type 2 diabetes mellitus (T2DM). The results show not only a significant difference of the aggregation in patients compared to healthy people, but also a correspondence between in vivo and in vitro parameters. Red blood cells aggregate in CHD patients faster and more numerously; in particular the aggregation index increases by 20 ± 7%. The presence of T2DM also significantly elevates aggregation in CHD patients. This work demonstrates multimodal diagnostics and monitoring of patients with socially significant pathologies.

In Vitro Assay for Single-cell Characterization of Impaired Deformability in Red Blood Cells under Recurrent Episodes of Hypoxia

Lab on a Chip ◽  
2021 ◽  
Author(s):  
YUHAO QIANG ◽  
Jia Liu ◽  
Ming Dao ◽  
E Du
Keyword(s):  
Shear Stress ◽  
Red Blood Cells ◽  
Single Cell ◽  
Blood Cells ◽  
Blood Circulation ◽  
In Vitro Assay ◽  
Vitro Assay ◽  
Cyclic Shear

Red blood cells (RBCs) are subjected to recurrent changes in shear stress and oxygen tension during blood circulation. The cyclic shear stress has been identified as an important factor that...

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