The adaptation of three isolates ofBabesia divergensto continuous culture in rat erythrocytes

Parasitology ◽  
1991 ◽  
Vol 103 (2) ◽  
pp. 165-170 ◽  
Author(s):  
N. Ben Musa ◽  
R. S. Phillips
Keyword(s):  
Red Blood Cells ◽  
Continuous Culture ◽  
Blood Cells ◽  
Calf Serum ◽  
The Other ◽  
Foetal Calf Serum ◽  
Rat Erythrocytes ◽  
Rpmi Medium ◽  
Babesia Divergens ◽  
High Parasitaemias

Three isolates ofBabesia divergenshave been cultured continuously for 6 months in rat erythrocytes using the candle jar technique (Trager & Jensen, 1976). One isolate was already rat-adapted, the other two became adapted to rats through continuous culture in rat erythrocytes. Parasites were cultured in rat erythrocytes in RPMI medium supplemented with 20% foetal calf serum. The highest parasitaemia obtained was 35% and multiparasitization of red blood cells was often observed. Cultures ofB. divergensremained infective to splenectomized rats. Cultures with high parasitaemias contained a large number of extracellular merozoites. When separated from the red blood cells, these extracellular merozoites retained their infectivity.

Early developmental changes of the schistosomula ofSchistosoma mansoni in vitroand in mouse lung

Parasitology ◽  
1978 ◽  
Vol 76 (3) ◽  
pp. 317-326 ◽  
Author(s):  
E. A. E. Imohiosen ◽  
Alan Sher ◽  
F. Von Lichtenberg
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Calf Serum ◽  
Skin Penetration ◽  
Developmental Changes ◽  
Mouse Lung ◽  
Foetal Calf Serum ◽  
Parasite Antigen ◽  
Early Developmental ◽  
Mouse Lungs

SummaryFresh (3 h) schistosomula ofSchistosoma mansoniwere obtained by the skin penetration method and injected intravenously into groups of mice either immediately or after 48 h incubation in tissue culture. Schistosomula were then recovered from the lungs 1 to 2 days after injection. The recovery results showed that the ability of uncultured schistosomula to emerge from lung tissue increased with time, became maximal on the 3rd day and diminished thereafter. In contrast, cultured schistosomula were able to emerge from chopped lung at a much earlier time after injection.Fresh schistosomula, as well as those recovered from mouse lungs, were assayed by indirect immunofluorescence for the presence of parasite and host antigens. Similarly, fresh schistosomula which had been incubated in foetal calf serum, with or without mouse red blood cells, were assayed for parasite and host antigens after 3–24 h of culture. Fresh schistosomula expressed parasite antigen with greater intensity than those recovered from mouse lungs and showed no trace of host antigen. Lung schistosomula, on the other hand, expressed less parasite antigen but more red blood cell antigen with increasing time in the host. Schistosomula cultured in the absence of mouse red blood cells expressed only parasite antigen throughout the period in culture, while those cultured in the presence of mouse red blood cells also expressed parasite antigen during the entire period in culture but, in addition, by 24 h host antigen could also be detected.These developmental and adaptational changes may play a role in determining the survival of parasites in the normal or immune host.

The importance of parasite load in the killing ofPlasmodium vinckeiin mice treated withCorynebacterium parvumor alloxan monohydrate

Parasitology ◽  
1984 ◽  
Vol 89 (3) ◽  
pp. 417-424 ◽  
Author(s):  
F. E. G. Cox ◽  
Stephanie M. Millott
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Parasite Load ◽  
Corynebacterium Parvum ◽  
Specific Immunity ◽  
Pre Treatment ◽  
Alloxan Monohydrate ◽  
High Parasitaemias ◽  
Plasmodium Vinckei

SUMMARYMice pre-treated withCorynebacterium parvumand later challenged withPlasmodium vinckeibecome infected but do not die whereas control mice do. When pre-treated mice were challenged with 1, 10, 1 × 102, 1 × 104, 1 × 105or 1 × 106parasites, the pre-patent periods correlated directly with the number of parasites injected, but the subsequent parasitaemias reached similar levels. This suggests that parasite killing, resulting from pre-treatment withC. parvum, is not triggered until the parasite load has reached a particular threshold. The injection of alloxan monohydrate, which brings about the release of toxic oxygen inter mediates thought to be involved in non-specific immunity, has little effect onP. vinckeiinfections until the parasitaemia is relatively high. This indicates that oxygen-mediated parasite killing also does not occur until the parasitaemia has reached a particular threshold. It is suggested that it is only at relatively high parasitaemias that the factors involved in parasite killing are able to enter the infected red blood cells.

scholarly journals Conversaziones 1951

1951 ◽  
Vol 9 (1) ◽  
pp. 138-143
Keyword(s):  
Biological Sciences ◽  
Medical Research ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Vice President ◽  
Living Cells ◽  
The Other ◽  
Freezing And Thawing ◽  
Men And Women ◽  
Rabbit Blood

The Society’s Conversaziones this year were held on Thursday, 24 May 1951 and on Thursday, 28 June 1951. At the former there were thirty exhibits and at the latter twenty-four. The exhibits ranged through physical and biological sciences and once again the Society gratefully acknowledges the contribution of the exhibitors towards making these evenings, when the Society is host to its many friends, so successful. At both Conversaziones two films were shown, one entitled ‘ The freezing and thawing of living cells ’ which illustrated the work of Mr C. Polge, Mr J. Smiles and Dr Audrey Smith of the National Institute for Medical Research, London : the other film was entitled ‘ Medical aspects of venomous snakes ’ made by the Wellcome Foundation Limited. The former film showed how suspensions of fowl spermatozoa and of rabbit blood cells in the presence of glycerol could be taken to temperatures of — 60° C and on raising the temperature, the spermatozoa resumed fertility and the red blood cells are preserved from haemolysis. The film describing the snakes was in colour : that part of the photography dealing with living snakes was made at the London Zoo—not without some interesting moments ! These films, and the exhibits for the first Soirée, were seen by some 250 scholars on the morning of Friday, 25 May. Sir David Brunt, Vice-President and Physical Secretary, welcomed these young men and women of science, and Professor Finch, Chairman of the Soiree Committee, addressed them on some of the exhibits which they were about to see. From communications received since, it is clearly evident that this invitation to science scholars in the London area is greatly appreciated.

scholarly journals Volume-responsive sodium and proton movements in dog red blood cells.

1984 ◽  
Vol 84 (3) ◽  
pp. 379-401 ◽  
Author(s):  
J C Parker ◽  
V Castranova
Keyword(s):  
Membrane Potential ◽  
Red Blood Cells ◽  
Fluorescent Probe ◽  
Blood Cells ◽  
Indirect Method ◽  
Cell Types ◽  
The Other ◽  
Na Transport ◽  
Transport Pathway ◽  
Transport Pathways

Shrinkage of dog red blood cells (RBC) activates a Na transport pathway that is Cl dependent, amiloride sensitive, and capable of conducting Na-proton counterflow. It is possible to establish transmembrane gradients for either Na or protons and to demonstrate that each cation species can drive reciprocal movements of the other. The nature of the coupling between Na and proton movements was investigated using the fluorescent probe diS-C3(5) and also by an indirect method in which K movements through valinomycin channels were used to draw inferences about the membrane potential. No evidence was found to suggest that the Na-proton pathway activated by shrinkage of dog RBC is a conductive one. By exclusion, it is presumed that the coupling between the counterflow of Na and protons is electroneutral. The volume-activated Na-proton fluxes in dog RBC have certain properties that distinguish them from similar transport pathways in other cell types.

scholarly journals Blood group D antigen content of nucleated red cell precursors

Blood ◽  
1977 ◽  
Vol 50 (6) ◽  
pp. 981-986 ◽  
Author(s):  
A Rearden ◽  
SP Masouredis
Keyword(s):  
Bone Marrow ◽  
Red Blood Cells ◽  
Blood Group ◽  
Blood Cells ◽  
Cell Types ◽  
The Other ◽  
Cell Maturation ◽  
Red Cell ◽  
D Antigen ◽  
Group D

Abstract The D antigen content of nucleated red cell precursors in human bone marrow was estimated using autoradiography and 125I-anti-D. D antigen first appeared in the pronormoblast, and the quantity of antigen progressively increased during red cell maturation. Maximal anti-D binding occurred on mature red blood cells. Pronormoblasts, basophilic normoblasts, polychromatophilic normoblasts, and orthochromatic normoblasts, respectively, had approximately 1/4, 1/2, 2/3, and 3/4 the quantity of antigen found on mature red cells. None of the other cell types were found in bone marrow labeled with anti-D.

scholarly journals Four-Dimensional Characterization of the Babesia divergens Asexual Life Cycle, from the Trophozoite to the Multiparasite Stage

mSphere ◽  
2020 ◽  
Vol 5 (5) ◽  
Author(s):  
José Javier Conesa ◽  
Elena Sevilla ◽  
María Carmen Terrón ◽  
Luis Miguel González ◽  
Jeremy Gray ◽  
...  
Keyword(s):  
Life Cycle ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Binary Fission ◽  
Life Cycle Model ◽  
Cycle Model ◽  
Babesia Divergens ◽  
Complex Population ◽  
Vertebrate Hosts ◽  
Kinetics Of

ABSTRACT Babesia is an apicomplexan parasite of significance that causes the disease known as babesiosis in domestic and wild animals and in humans worldwide. Babesia infects vertebrate hosts and reproduces asexually by a form of binary fission within erythrocytes/red blood cells (RBCs), yielding a complex pleomorphic population of intraerythrocytic parasites. Seven of them, clearly visible in human RBCs infected with Babesia divergens, are considered the main forms and named single, double, and quadruple trophozoites, paired and double paired pyriforms, tetrad or Maltese Cross, and multiparasite stage. However, these main intraerythrocytic forms coexist with RBCs infected with transient parasite combinations of unclear origin and development. In fact, little is understood about how Babesia builds this complex population during its asexual life cycle. By combining cryo-soft X-ray tomography and video microscopy, main and transitory parasites were characterized in a native whole cellular context and at nanometric resolution. The architecture and kinetics of the parasite population was observed in detail and provide additional data to the previous B. divergens asexual life cycle model that was built on light microscopy. Importantly, the process of multiplication by binary fission, involving budding, was visualized in live parasites for the first time, revealing that fundamental changes in cell shape and continuous rounds of multiplication occur as the parasites go through their asexual multiplication cycle. A four-dimensional asexual life cycle model was built highlighting the origin of several transient morphological forms that, surprisingly, intersperse in a chronological order between one main stage and the next in the cycle. IMPORTANCE Babesiosis is a disease caused by intraerythrocytic Babesia parasites, which possess many clinical features that are similar to those of malaria. This worldwide disease is increasing in frequency and geographical range and has a significant impact on human and animal health. Babesia divergens is one of the species responsible for human and cattle babesiosis causing death unless treated promptly. When B. divergens infects its vertebrate hosts, it reproduces asexually within red blood cells. During its asexual life cycle, B. divergens builds a population of numerous intraerythrocytic (IE) parasites of difficult interpretation. This complex population is largely unexplored, and we have therefore combined three- and four-dimensional imaging techniques to elucidate the origin, architecture, and kinetics of IE parasites. Unveiling the nature of these parasites has provided a vision of the B. divergens asexual cycle in unprecedented detail and is a key step to develop control strategies against babesiosis.

An Assay to Predict L-Asparaginase Neutralization and Enzyme Loaded Red Blood Cells to Maintain in Vivo Efficacy.

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 907-907
Author(s):  
Emmanuelle Dufour ◽  
Christine Saban-Vianey ◽  
Henri Coquelin ◽  
Yann Godfrin
Keyword(s):  
Enzyme Activity ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Neutralizing Antibodies ◽  
Protein A ◽  
The Other ◽  
Total Enzyme Activity ◽  
E Coli ◽  
Asparaginase Activity

Abstract E. coli. L-Asparaginase repeated injections induce immunization. Anti-Asparaginase antibodies can provoke clinical hypersensitivity reactions and/or silently inactivate enzyme activity. Consequently, L-Asparaginase clearance is increased, implying a lack of L-asparagine deamination. Firstly, we developed an assay able to detect the presence of neutralizing factors including anti-Asparaginase antibodies. Next we investigated in a mouse model if loading L-Asparaginase into red blood cells (RBC) may be a way to protect its activity against neutralizing factors. A rabbit was immunized injecting 0.5 mg of L-Asparaginase (167 IU) mixed with Freund’s adjuvant every 3 weeks for 4-fold. The animal was euthanized and the final serum collected. Part of this final serum was immuno-adsorbed onto protein A for IgG antibodies purification. L-Asparaginase activity was measured by monitoring the kinetics of ammonia generation from the hydrolysis of asparagine. This assay was adapted to a biochemistry automated analyzer. When mixed with undiluted serum from the immunized rabbit, L-Asparaginase activity (0.8 to 100 IU/ml) was totally inhibited for all the concentration range within 15 min at 37°C. In the other hand, up to 1/128 serial dilutions of serum totally inhibited 2 IU/ml L-Asparaginase. As a control, undiluted pre-immunization serum from the same animal did not significantly affect L-Asparaginase activity. To identify the neutralizing factors, IgG from serum were purified by protein-A. As performed with serum, successive dilutions of IgG were mixed with 1.25 IU/ml L-Asparaginase. The IgG inhibited enzyme activity at the 1/128 dilution by 97%, thus proving their neutralizing effect on L-Asparaginase. To simulate the presence of neutralizing antibodies in the patient, we injected 7.5 μg of rabbit IgG into OF1 mice. Control mice were injected with phosphate buffered saline (PBS). Twenty minutes later mice either received 80 IU/kg of native E. coli L-Asparaginase or the same dose entrapped into OF1 mouse RBC. L-Asparaginase was loaded into murine RBC by reversible hypotonic dialysis, followed by a resealing step. The RBC thus acts as a bioreactor where plasmatic asparagine enters and is cleaved by the entrapped L-Asparaginase inside the erythrocyte. L-Asparaginase activity inside the erythrocyte was quantified at 68 IU per ml of erythrocytes, and the extracellular enzyme activity was less to 9% of total enzyme activity. Mice were sacrificed 6 hours after the administration of native or encapsulated L-Asparaginase. Free L-Asparaginase was totally inactivated in plasma of anti-Asparaginase IgG pre-treated mice: 0.002 ±0.002 IU/ml vs 0.417 ±0.103 IU/ml in PBS pre-treated mice. In addition, when L-Asparaginase is loaded inside RBC the activity is maintained irrespective of the presence of antibodies (0.798 ±0.126 IU/ml with IgG vs 0.879 ±0.146 IU/ml without). Moreover asparagine was not deaminated in IgG pre-treated mice who received free L-Asparaginase (27 ±1.6 μmol/L), while below 2 μmol/L in all the other groups. In conclusion, this newly developed assay can predict in vivo L-Asparaginase inefficacy. In addition, L-Asparaginase loaded into RBC is protected against neutralizing antibodies and its efficacy is maintained.

CHARACTERISTIC OF ANEMIC SYNDROME IN ONCOLOGIC PATIENTS WITH SEPSIS IN THE EARLY POST-OPERATIVE PERIOD

2020 ◽  
Vol 65 (3) ◽  
pp. 169-173
Author(s):  
Valentina Nikolaevna Blindar ◽  
M. M. Dobrovolskaya ◽  
G. N. Zubrikhina ◽  
T. V. Davydova ◽  
A. V. Sytov ◽  
...  
Keyword(s):  
Chronic Disease ◽  
Iron Deficiency ◽  
Red Blood Cells ◽  
Cancer Patients ◽  
Blood Cells ◽  
The Other ◽  
Normal Range ◽  
Post Operative Period ◽  
Oncologic Patients

A study of the main indicators of red blood (RBC, HGB, HCT, MCV, MCH) and the concentration of EPO, sTfR in 9 cancer patients with anemic syndrome (AS) against sepsis was carried out. Among them, patients with chronic disease anemia (ACh), with normocytic, normochromic characteristics of red blood cells and low hematocrit predominated. In 2 patients, microcytosis and erythrocyte hypochromia were noted, the concentration of sTfR was significantly higher than normal (0.9 ± 0.07 μg / ml), amounted to 2.7 μg / ml in one of them and 1.9 μg / ml in the other, which testified to t iron deficiency erythropoiesis (IDE) on the background of the ACh,. In 7 patients with ACh without IDE, sTfR values were within the normal range (0.1-1.2) μg / ml, the median was 0.5 μg/ml. In all patients with sepsis, the production of EPO was inadequate for the severity of the AS, to a lesser extent in patients with IDE. The average EPO production in the group was 19.4 ± 5.1 (7.7-52.8) mU / ml, median = 12.1 mE / ml. Further studies of EPO, sTfR are planned in order to determine their role in therapeutic tactics in the correction of AS in cancer patients with sepsis.

scholarly journals STUDIES CONCERNING THE PATHOGENESIS OF GAUCHER’S DISEASE

Blood ◽  
1948 ◽  
Vol 3 (11) ◽  
pp. 1250-1258 ◽  
Author(s):  
BERTHA OTTENSTEIN ◽  
GERHARD SCHMIDT ◽  
S. J. THANNHAUSER
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
The Other ◽  
Gaucher's Disease ◽  
Gaucher’S Disease ◽  
Reticulum Cells ◽  
Normal Individuals ◽  
Intracellular Metabolism

Abstract 1. The serum of normal individuals and of patients with Gaucher’s disease does not contain cerebrosides in measurable amounts. Cerebrosides in Gaucher’s disease are increased only in those organs containing abundant numbers of cells characteristic of the disease. 2. Normal red blood cells contain approximately 0.19 per cent cerebrosides. The cerebroside in red blood cells is a galactosidocerebroside. 3. Red blood cells in Gaucher’s disease do not differ quantitatively and qualitatively in their cerebroside content from the red blood cells of normal individuals. 4. In four different cases of Gaucher’s disease separate determinations of splenic galactosido- and glucosidocerebrosides were made. The spleen of two adults showed mainly glucosidocerebrosides and only traces of galactosidocerebrosides, while the analysis of the spleen of two other adults showed that galactosido- as well as glucosidocerebrosides may be accumulated simultaneously in Gaucher cells. These findings are of importance, since it is demonstrated that the deviation of the cerebroside metabolism in Gaucher cells not only results in the formation of an abnormal glucosidocerebroside, but also may lead to the increased formation of the normal galactosidocerebroside, kerasin. It is demonstrated that the relative proportions of galactosido- and glucosidocerebrosides in Gaucher cells may differ considerably in individual cases. 5. The organs of infantile siblings with "generalized infantile Gaucher’s" disease were analyzed. The organs of one infant showed mainly galactosidocerebrosides while in the organs of the other sibling both kinds of cerebrosides, glucosido- as well as galactosidocerebrosides, were present. 6. The findings reported in this paper lend support to the theory that Gaucher’s disease is the result of a deviation of the intracellular metabolism of reticulum cells and histiocytes. The cerebrosides are not transported by the serum or by the red blood cells and secondarily deposited in the cells involved, but are formed and stored in the reticulum cells and histiocytes were they are found.

To the pathogenesis of anemia in children

1930 ◽  
Vol 26 (4) ◽  
pp. 346-353
Author(s):  
E. P. Krever
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
The State ◽  
The Body ◽  
The Other ◽  
Other Hand ◽  
The Difference ◽  
The One

Diseases that cause anemia are very diverse, and therefore it is very difficult to classify anemias according to their etiology, and due to various constitutional and other characteristics of the organism, the same cause can cause different phenomena. It is easier to approach the question of the cause of anemia by determining whether erythropoiesis suffers from this disease or whether there is an increased breakdown of red blood cells. In the body, the state of the blood is composed of two processes: on the one hand, erythropoiesis, on the other hand, the decay of erythrocytes. Demonstrative formula Yerringer'a E R D (Blutmauserung), where E is the number of erythrocytes, P is their production and D ~ destruction. As long as P balances M, the difference E. remains unchanged. If D, that is, hemolysis, increases more than P, then we get a hemolytic type of anemia. If D hemolysis remains unchanged, but P decreases we get an aplastic type of anemia.

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