scholarly journals In vitro rosetting, cytoadherence, and microagglutination properties of Plasmodium falciparum-infected erythrocytes from Gambian and Tanzanian patients

Blood ◽  
1990 ◽  
Vol 76 (9) ◽  
pp. 1845-1852
Author(s):  
T Hasler ◽  
SM Handunnetti ◽  
JC Aguiar ◽  
MR van Schravendijk ◽  
BM Greenwood ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Infected Cell ◽  
Blood Cells ◽  
Molecular Mechanisms ◽  
Melanoma Cells ◽  
Schizont Stage ◽  
Ring Stage ◽  
Cell Binding ◽  
Blood Samples

To understand the molecular mechanisms that lead to sequestration of red blood cells infected with mature stages of Plasmodium falciparum and to examine the relevance of earlier studies on adherence properties of laboratory-derived P falciparum parasites to the natural parasite population, we analyzed Gambian and Tanzanian isolates for in vitro cytoadherence and antibody-mediated microagglutination. Eighteen cryopreserved isolates of ring-stage parasites were cultured for 20 to 30 hours in vitro, in the patients original erythrocytes, to the trophozoite and schizont stage. All parasites were positive in the microagglutination assay with at least one of four African hyperimmune sera. In a rosetting assay, only 2 of the 18 isolates were strongly positive (35% and 41% of parasitized erythrocytes with more than two uninfected cells bound). Thirteen isolates showed either intermediate (5% to 18%) or low (less than 5%) rosetting while three isolates did not form rosettes. Infected cell-binding of the different isolates to immobilized CD36 or thrombospondin, or C32 melanoma cells correlated with the percentage of mature parasites in the blood samples (r = .932 for CD36, r = .946 for thrombospondin, and r = .881 for C32 melanoma cells). There was a high correlation between binding to CD36 and thrombospondin (r = .982). The extent of infected cell rosetting with uninfected cells in these blood samples was not correlated with these other receptor properties. We also observed coexpression of rosetting and cytoadherence receptors on the same parasitized erythrocytes.

scholarly journals In vitro rosetting, cytoadherence, and microagglutination properties of Plasmodium falciparum-infected erythrocytes from Gambian and Tanzanian patients

Blood ◽  
1990 ◽  
Vol 76 (9) ◽  
pp. 1845-1852 ◽  
Author(s):  
T Hasler ◽  
SM Handunnetti ◽  
JC Aguiar ◽  
MR van Schravendijk ◽  
BM Greenwood ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Infected Cell ◽  
Blood Cells ◽  
Molecular Mechanisms ◽  
Melanoma Cells ◽  
Schizont Stage ◽  
Ring Stage ◽  
Cell Binding ◽  
Blood Samples

Abstract To understand the molecular mechanisms that lead to sequestration of red blood cells infected with mature stages of Plasmodium falciparum and to examine the relevance of earlier studies on adherence properties of laboratory-derived P falciparum parasites to the natural parasite population, we analyzed Gambian and Tanzanian isolates for in vitro cytoadherence and antibody-mediated microagglutination. Eighteen cryopreserved isolates of ring-stage parasites were cultured for 20 to 30 hours in vitro, in the patients original erythrocytes, to the trophozoite and schizont stage. All parasites were positive in the microagglutination assay with at least one of four African hyperimmune sera. In a rosetting assay, only 2 of the 18 isolates were strongly positive (35% and 41% of parasitized erythrocytes with more than two uninfected cells bound). Thirteen isolates showed either intermediate (5% to 18%) or low (less than 5%) rosetting while three isolates did not form rosettes. Infected cell-binding of the different isolates to immobilized CD36 or thrombospondin, or C32 melanoma cells correlated with the percentage of mature parasites in the blood samples (r = .932 for CD36, r = .946 for thrombospondin, and r = .881 for C32 melanoma cells). There was a high correlation between binding to CD36 and thrombospondin (r = .982). The extent of infected cell rosetting with uninfected cells in these blood samples was not correlated with these other receptor properties. We also observed coexpression of rosetting and cytoadherence receptors on the same parasitized erythrocytes.

scholarly journals Alteration in cytoadherence and rosetting of Plasmodium falciparum- infected thalassemic red blood cells

Blood ◽  
1993 ◽  
Vol 82 (12) ◽  
pp. 3752-3759 ◽  
Author(s):  
R Udomsangpetch ◽  
T Sueblinvong ◽  
K Pattanapanyasat ◽  
A Dharmkrong-at ◽  
A Kittikalayawong ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Plasmodium Falciparum ◽  
Blood Cell ◽  
Red Blood Cells ◽  
Red Blood Cell ◽  
Blood Cells ◽  
Protective Role ◽  
Immune Serum ◽  
Schizont Stage ◽  
Ring Stage

Abstract Hemoglobinopathies have a protective role in malaria that appears to be related to alterations in red blood cell (RBC) properties. Thalassemic RBCs infected with Plasmodium falciparum showed greatly reduced cytoadherence and rosetting properties as well as impaired growth and multiplication. A significant decrease in the levels of falciparum antigens associated with the membrane of infected beta-thalassemic RBCs was observed at trophozoite/schizont stage, but not young ring stage. This reduction was shown when a cytoadherence inhibitory monoclonal antibody, but not a noninhibitory pooled immune serum, was used. These observations suggest that protection against malaria in thalassemia is caused by both reduced parasitemias and altered adherence properties of the infected thalassemic RBCs that promote enhanced clearance of the parasite from the circulation.

scholarly journals The transcriptome of circulating sexually committed Plasmodium falciparum ring stage parasites forecasts malaria transmission potential

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Surendra K. Prajapati ◽  
Ruth Ayanful-Torgby ◽  
Zuleima Pava ◽  
Michelle C. Barbeau ◽  
Festus K. Acquah ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Transcription Factor ◽  
Ex Vivo ◽  
Ring Stage ◽  
Sexual Stage ◽  
Blood Samples ◽  
Transmission Potential ◽  
In Vivo Analysis

AbstractMalaria is spread by the transmission of sexual stage parasites, called gametocytes. However, with Plasmodium falciparum, gametocytes can only be detected in peripheral blood when they are mature and transmissible to a mosquito, which complicates control efforts. Here, we identify the set of genes overexpressed in patient blood samples with high levels of gametocyte-committed ring stage parasites. Expression of all 18 genes is regulated by transcription factor AP2-G, which is required for gametocytogenesis. We select three genes, not expressed in mature gametocytes, to develop as biomarkers. All three biomarkers we validate in vitro using 6 different parasite lines and develop an algorithm that predicts gametocyte production in ex vivo samples and volunteer infection studies. The biomarkers are also sensitive enough to monitor gametocyte production in asymptomatic P. falciparum carriers allowing early detection and treatment of infectious reservoirs, as well as the in vivo analysis of factors that modulate sexual conversion.

scholarly journals Alteration in cytoadherence and rosetting of Plasmodium falciparum- infected thalassemic red blood cells

Blood ◽  
1993 ◽  
Vol 82 (12) ◽  
pp. 3752-3759
Author(s):  
R Udomsangpetch ◽  
T Sueblinvong ◽  
K Pattanapanyasat ◽  
A Dharmkrong-at ◽  
A Kittikalayawong ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Plasmodium Falciparum ◽  
Blood Cell ◽  
Red Blood Cells ◽  
Red Blood Cell ◽  
Blood Cells ◽  
Protective Role ◽  
Immune Serum ◽  
Schizont Stage ◽  
Ring Stage

Hemoglobinopathies have a protective role in malaria that appears to be related to alterations in red blood cell (RBC) properties. Thalassemic RBCs infected with Plasmodium falciparum showed greatly reduced cytoadherence and rosetting properties as well as impaired growth and multiplication. A significant decrease in the levels of falciparum antigens associated with the membrane of infected beta-thalassemic RBCs was observed at trophozoite/schizont stage, but not young ring stage. This reduction was shown when a cytoadherence inhibitory monoclonal antibody, but not a noninhibitory pooled immune serum, was used. These observations suggest that protection against malaria in thalassemia is caused by both reduced parasitemias and altered adherence properties of the infected thalassemic RBCs that promote enhanced clearance of the parasite from the circulation.

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 ring-stage of Plasmodium falciparum observed in RBCs of hospitalized malaria patients

The Analyst ◽  
2015 ◽  
Vol 140 (23) ◽  
pp. 8007-8016 ◽  
Author(s):  
Mateusz Kozicki ◽  
Jacek Czepiel ◽  
Grażyna Biesiada ◽  
Piotr Nowak ◽  
Aleksander Garlicki ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Raman Spectra ◽  
Ring Stage ◽  
Blood Samples

Raman spectra of the blood samples obtained directly from hospitalized malaria patients withPlasmodium falciparum(P. falciparum) in the ring-stage were analyzed.

scholarly journals Acetylsalicylic acid and morphology of red blood cells

2010 ◽  
Vol 53 (3) ◽  
pp. 575-582 ◽  
Author(s):  
Jacques Natan Grinapel Frydman ◽  
Adenilson de Souza da Fonseca ◽  
Vanessa Câmara da Rocha ◽  
Monica Oliveira Benarroz ◽  
Gabrielle de Souza Rocha ◽  
...  
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Control Group ◽  
Blood Samples ◽  
Morphological Alterations ◽  
Blood Smears ◽  
In Vivo Treatment ◽  
Microscopy Data

This work evaluated the effect of in vitro and in vivo treatment with ASA on the morphology of the red blood cells. Blood samples or Wistar rats were treated with ASA for one hour. Blood samples or animals treated with saline were used as control group. Blood smears were prepared, fixed, stained and the qualitative and quantitative morphology of red blood cells were evaluated under optical microscopy. Data showed that the in vitro treatment for one hour with ASA at higher dose used significantly (p<0.05) modified the perimeter/area ratio of the red blood cells. No morphological alterations were obtained with the in vivo treatment. ASA use at highest doses could interfere on shape of red blood cells.

scholarly journals Comparison of the activation capabilities of hemosorbents by adhesion rate of blood cells in vitro

2021 ◽  
Vol 8 (5) ◽  
pp. 57-66
Author(s):  
S. I. Kuznetsov ◽  
O. P. Kirichuk ◽  
N. V. Burkova ◽  
G. O. Yuriev ◽  
V. A. Davankov ◽  
...  
Keyword(s):  
Clinical Practice ◽  
Blood Cells ◽  
Solid Phase ◽  
Activation Functions ◽  
Activation Effect ◽  
Blood Samples ◽  
Adhesion Rate ◽  
Low Volume ◽  
Donated Blood

Background: The relevance of the work lies in the search for new hemocontact drugs with hemocompatibility and a pronounced activation effect on the cellular and humoral blood systems for their possible use in clinical practice during low-volume hemoperfusion.The aim of this work was to assess the activation capabilities of three granular hemosorbents by the rate of adhesion of blood cellular elements to the surface of granules in vitro.Materials and methods. When using the method of low-volume hemoperfusion (LVH) in the clinic it is important to take into account the activation properties of solid-phase granular drugs. Blood-contact interaction was carried out in bench conditions with the use of donated blood in rotary mode. Blood samples were taken before the experiment and after 5, 20, 40 and 60 minutes. Changes in blood cell and subcellular populations were evaluated using the Sysmex XT 1800i hematological analyzer (26 parameters), which made it possible to indirectly judge the activation of blood cells. 30 experiments were conducted. To analyze the activation functions of the hemocontact preparations the speed-time adhesive profile of blood cells on the sorbent was used.Results. The effect of using the preparations Silochrome S-120 and SPS in comparison with SСT-6A HP as contact hemoactivators can be more pronounced, since the activation potential of these sorbents for blood cells is much higher. Silochrome S-120 has the highest activation capabilities compared to SPS and SKT-6A HP.Conclusion. Adhesion rate indicators can be indicators of the activation of blood cells upon contact with foreign surfaces and serve as a criterion for assessing the activation capabilities of these surfaces when using the LVH method in the clinic.

scholarly journals A Profound Membrane Reorganization Defines Susceptibility of Plasmodium falciparum Infected Red Blood Cells to Lysis by Granulysin and Perforin

2021 ◽  
Vol 12 ◽  
Author(s):  
Maria Andrea Hernández-Castañeda ◽  
Marilyne Lavergne ◽  
Pierina Casanova ◽  
Bryan Nydegger ◽  
Carla Merten ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Molecular Mechanisms ◽  
Γδ T Cells ◽  
Parasite Growth ◽  
Complex Life Cycle ◽  
Cholesterol Depletion ◽  
Host Cell Membrane ◽  
Pore Forming Proteins

Malaria remains one of the most serious health problems in developing countries. The causative agent of malaria, Plasmodium spp., have a complex life cycle involving multiple developmental stages as well as different morphological, biochemical and metabolic requirements. We recently found that γδ T cells control parasite growth using pore-forming proteins to deliver their cytotoxic proteases, the granzymes, into blood residing parasites. Here, we follow up on the molecular mechanisms of parasite growth inhibition by human pore-forming proteins. We confirm that Plasmodium falciparum infection efficiently depletes the red blood cells of cholesterol, which renders the parasite surrounding membranes susceptible to lysis by prokaryotic membrane disrupting proteins, such as lymphocytic granulysin or the human cathelicidin LL-37. Interestingly, not the cholesterol depletion but rather the simultaneous exposure of phosphatidylserine, a negatively charged phospholipid, triggers resistance of late stage parasitized red blood cells towards the eukaryotic pore forming protein perforin. Overall, by revealing the molecular events we establish here a pathogen-host interaction that involves host cell membrane remodeling that defines the susceptibility towards cytolytic molecules.

Blood Volumes of Dairy Calves Comparing Cr51-Tagged Red Blood Cells and T-1824 Plasma Dilution Methods

1958 ◽  
Vol 193 (2) ◽  
pp. 244-248 ◽  
Author(s):  
Perry Ruth Stahl ◽  
Homer E. Dale
Keyword(s):  
Body Weight ◽  
Red Blood Cells ◽  
Whole Blood ◽  
Blood Cells ◽  
Dairy Calves ◽  
Computation Method ◽  
Blood Samples ◽  
Whole Blood Samples ◽  
Blood Volumes

In a repeated study on 17 dairy calves, T-1824 dye plasma dilution showed significantly higher blood volumes than were found by any other technique or computation method using Cr51-tagged red blood cells. Five blood samples taken at 20-minute intervals after injection showed consistent decrease in radioactivity count from the first to the last sample, indicating greater accuracy in radioactivity dilution regressed to zero time figures than in average counts of several postinjection samples. In vitro studies suggest a loss of Cr51 from red blood cells to plasma after saline washings are Cr-free. Percentage blood volumes computed from whole blood samples of calves injected with Cr51-tagged red blood cells decreased in a straight line relationship with increase of body weight. Percentage plasma and whole blood volumes estimated with the T-1824 dye technique decreased regularly with body weight increase until a second determination was made when there was a rapid rise nearly to the level of the smallest calves, followed by another regular decrease with increase in weight. It is suggested that repeated dye injections do not always measure the same space. Regressed values of five whole blood samples taken at 20-minute intervals after injection of Cr51 tagged red blood cells gave more consistent blood volume determinations than either the weighed red cells or the plasma dye dilutions of the same samples.

Sign in / Sign up

Export Citation Format

Share Document