An in Vitro Model for Arsine Toxicity Using Isolated Red Blood Cells

ABSTRACTIn theSaimiri sciureusmonkey, erythrocytes infected with the varO antigenic variant of thePlasmodium falciparumPalo Alto 89F5 clone bind uninfected red blood cells (rosetting), form autoagglutinates, and have a high multiplication rate, three phenotypic characteristics that are associated with severe malaria in human patients. We report here that varO parasites express avargene having the characteristics of group Avargenes, and we show that the varO Duffy binding-like 1α1(DBL1α1) domain is implicated in the rosetting of bothS. sciureusand human erythrocytes. The soluble varO N-terminal sequence (NTS)-DBL1α1recombinant domain, produced in a baculovirus-insect cell system, induced high titers of antibodies that reacted with varO-infected red blood cells and disrupted varO rosettes. varO parasites were culture adapted in vitro using human erythrocytes. They formed rosettes and autoagglutinates, and they had the same surface serotype and expressed the samevarOgene as the monkey-propagated parasites. To develop an in vitro model with highly homogeneous varO parasites, rosette purification was combined with positive selection by panning with a varO NTS-DBL1α1-specific mouse monoclonal antibody. The single-variant, clonal parasites were used to analyze seroprevalence for varO at the village level in a setting where malaria is holoendemic (Dielmo, Senegal). We found 93.6% (95% confidence interval, 89.7 to 96.4%) seroprevalence for varO surface-reacting antibodies and 86.7% (95% confidence interval, 82.8 to 91.6%) seroprevalence for the recombinant NTS-DBL1α1domain, and virtually all permanent residents had seroconverted by the age of 5 years. These data imply that the varO model is a relevant in vivo and in vitro model for rosetting and autoagglutination that can be used for rational development of vaccine candidates and therapeutic strategies aimed at preventing malaria pathology.

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Evaluation of erythropoiesis in long-term hamster bone marrow suspension cultures: absence of a requirement for adherent monolayer cells

Blood ◽

10.1182/blood.v60.4.999.bloodjournal604999 ◽

1982 ◽

Vol 60 (4) ◽

pp. 999-1006

Author(s):

CE Eastment ◽

FW Ruscetti

Keyword(s):

Bone Marrow ◽

Red Blood Cells ◽

Blood Cells ◽

Adherent Cell ◽

Erythroid Progenitors ◽

Large Numbers ◽

Bone Marrow Cultures ◽

Vitro Model

In long-term hamster bone marrow cultures, proliferation and differentiation of hemopoietic stem cells occurs for several months without need for hydrocortisone or adherent stromal elements, which are requirements for bone marrow growth in all other species studied. Only the most primitive erythroid progenitors (BFU-E) are produced in the cultures. Following treatment of the cells with erythropoietin, these progenitor cells undergo differentiation into mature hemoglobinized red blood cells. Concomitant addition of erythropoietin (Epo) and prostaglandin-E1 (PGE1) results in the production of large numbers of maturing red blood cells. In cultures stimulated with Epo and PGE1, as many as 70% of the cells are benzidine-positive, while Epo alone stimulated as many as 45% of the cells to become erythroid. Epo and PGE1 do not have any apparent deleterious effect on the continuous hemopoiesis occurring in these cultures. Under identical conditions, syngeneic adherent cell cultures do not produce any erythroid elements. The development of mature red blood cells from primitive erythroid precursors occurs in the presence of Epo alone and without any apparent need for adherent stromal elements. These cultures provide a useful in vitro model for dissecting the positive and negative signals that regulate erythropoiesis.

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THE EFFECT OF COD LIVER OIL INTAKE ON THE STIMULATION OF BLOOD CELLS

10.1055/s-0038-1643406 ◽

1987 ◽

Author(s):

J B Hansen ◽

J O Olsen ◽

L Wilagård ◽

B Østerud

Keyword(s):

Platelet Aggregation ◽

Young Women ◽

Whole Blood ◽

Blood Cells ◽

In Vitro Model ◽

Cod Liver Oil ◽

Blood Samples ◽

Vitro Model ◽

Stimulation Of

In an in vitro model, stimulation of blood cells with a low concentration of lipopolysaccharides (LPS) revealed differences between women and men that possibly could be an explanation to why young women have less coronary heart disease than men (see abstract Hansen et al. “A model to--”).This model was also used to study the effect of intake of cod liver oil (CLO). 40 students (20 men and 20 women) were tested followed by an intake of 25 ml CLO daily for 2 months by 20 of the students.Heparinized blood samples were incubated with 2 ng LPS/ ml for 2 hours followed by isolation of plasma for thromboxane B2 and 6-keto-PG 1α quantitation.After the first 2 months period of CLO drinking we have the following results:The two months of CLO intake had no significant effect pn the thromboplastin induced synthesis in monocytes. In addition platelet aggregation was tested in a whole blood aggregometer using ADP addition to heparinized blood or collagen induced platelet aggregation in citrated whole blood. ADP aggregation was reduced from 75.9 ± 16.8% to 55.4 ± 19% in the CLO group of women, whereas the reduction in the CLO group of men was 70.1 ± 17.1% to 60.9±18.6%. Similar result were found with collagen aggregation (57% to 33% for women and 48% to 30% for men).It is concluded that CLO intake reduces TxA2 production and plateletaggregation without having reduced effect on PGI2 production in whole blood.

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Gender differences and inflammation: an in vitro model of blood cells stimulation in prepubescent children

Journal of Inflammation ◽

10.1186/1476-9255-7-28 ◽

2010 ◽

Vol 7 (1) ◽

pp. 28 ◽

Cited By ~ 23

Author(s):

Georges JA Casimir ◽

Fabienne Heldenbergh ◽

Laurence Hanssens ◽

Sandra Mulier ◽

Claudine Heinrichs ◽

...

Keyword(s):

Gender Differences ◽

Blood Cells ◽

In Vitro Model ◽

Vitro Model

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Evaluation of erythropoiesis in long-term hamster bone marrow suspension cultures: absence of a requirement for adherent monolayer cells

Blood ◽

10.1182/blood.v60.4.999.999 ◽

1982 ◽

Vol 60 (4) ◽

pp. 999-1006 ◽

Cited By ~ 4

Author(s):

CE Eastment ◽

FW Ruscetti

Keyword(s):

Bone Marrow ◽

Red Blood Cells ◽

Blood Cells ◽

Adherent Cell ◽

Erythroid Progenitors ◽

Large Numbers ◽

Bone Marrow Cultures ◽

Vitro Model

Abstract In long-term hamster bone marrow cultures, proliferation and differentiation of hemopoietic stem cells occurs for several months without need for hydrocortisone or adherent stromal elements, which are requirements for bone marrow growth in all other species studied. Only the most primitive erythroid progenitors (BFU-E) are produced in the cultures. Following treatment of the cells with erythropoietin, these progenitor cells undergo differentiation into mature hemoglobinized red blood cells. Concomitant addition of erythropoietin (Epo) and prostaglandin-E1 (PGE1) results in the production of large numbers of maturing red blood cells. In cultures stimulated with Epo and PGE1, as many as 70% of the cells are benzidine-positive, while Epo alone stimulated as many as 45% of the cells to become erythroid. Epo and PGE1 do not have any apparent deleterious effect on the continuous hemopoiesis occurring in these cultures. Under identical conditions, syngeneic adherent cell cultures do not produce any erythroid elements. The development of mature red blood cells from primitive erythroid precursors occurs in the presence of Epo alone and without any apparent need for adherent stromal elements. These cultures provide a useful in vitro model for dissecting the positive and negative signals that regulate erythropoiesis.

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The effect of physiological levels of South African puff adder (Bitis arietans) snake venom on blood cells: an in vitro model

Scientific Reports ◽

10.1038/srep35988 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 5

Author(s):

Morné A. Strydom ◽

Janette Bester ◽

Sthembile Mbotwe ◽

Etheresia Pretorius

Keyword(s):

South African ◽

Snake Venom ◽

Blood Cells ◽

In Vitro Model ◽

Vitro Model

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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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