Erythrocyte membrane cholesterol and lipid core growth in a rabbit model of atherosclerosis: modulatory effects of rosuvastatin.

PubMed

Tziakas, Dimitrios; Chalikias, Georgios; Kapelouzou, Alkistis; Tentes, Ioannis; Schäfer, Katrin; Karayannakos, Panagiotis; Kostakis, Alkiviadis; Boudoulas, Harissios; Konstantinides, Stavros

2013-12-10

Lipid core expansion is partly responsible for the conversion of a stable atherosclerotic lesion to a rupture-prone plaque. Intraplaque hemorrhage contributes to the accumulation of cholesterol within unstable plaques. In the present study, we investigated, using a rabbit model of atherosclerosis, the extent to which diet-induced increases in cholesterol content of erythrocyte membranes (CEM) contribute to lipid core expansion and the modulatory effect of rosuvastatin use. Rabbits fed with atherogenic diet (0.75% cholesterol) for 5 months exhibited advanced atherosclerotic lesions (mean plaque area, 0.39 ± 0.03 mm(2)), and lipid core size was associated with the concentration-time integral (CTI) of CEM levels (r=0.567, P=0.004) independent of other established predictors of lipid core size. Further experiments were performed by feeding rabbits atherogenic diet (1% cholesterol) for 3 months, followed by either normal diet or normal diet plus rosuvastatin for the next 3 months. Although no differences were observed in total plaque area between both groups, administration of rosuvastatin was associated with significantly smaller lipid cores, fewer macrophages within the lipid core, less microvessels as well as with lower CTI of CEM levels compared to normal diet alone. Moreover, intraplaque erythrocyte membranes covered a smaller lipid core area in rabbits under rosuvastatin plus normal diet as opposed to rabbits under diet alone. Increased CEM levels, induced by high-cholesterol diet, are associated with lipid core growth. Ingestion of a potent HMG-CoA reductase inhibitor (rosuvastatin) may decrease CEM levels, and this effect may contribute to regression of the lipid core. © 2013.

Studies on the interaction of the Sophora japonica lectin and concanavalin A with erythrocytes and lymphocytes.

PubMed Central

Poretz, R D; Barth, R F

1976-01-01

The agglutinating activity of lectins from the seeds of Sophora japonica and Canavalia ensiformis (concanavalin A) with human and murine erythrocytes and lymphocytes have been compared to one another and related to the mitogenic and immunosuppressive properties of these purified proteins. The S. japonica lectin, which demonstrates blood group specificity, is more active than concanavalin A with human erythrocytes, but has a much lower reactivity than concanavalin A with murine red blood cells. Ficin treatment of human erythrocytes results in an increase in agglutinability by both lectins as well as causing the appearance of S. japonica lectin receptors on type O cells. Treatment of murine reythrocytes with ficin alone or followed by beta-galactosidase causes the cells to be more reactive with concanavalin A. Beta-Galactosidase alone has no observable affect on the cells. In contrast, the agglutinability of cells by the S. japonica lectin increases after ficin treatment but is not affected by beta-galaetosidose treatment either after or in the absence of ficinization. Murine lymphocytes react with both lectins in a manner paralleling the agglutination patterns of murine erythrocytes. The S. japonica lectin appears to be devoid of mitogenic and immuno-suppressive activity, in contrast to concanavalin A which suppresses the T helper-dependent antibody response to sheep erythrocytes. These results are discussed in terms of the types of lectin receptors on lymphocytes related to agglutination, induction of blastogenesis and immuno-suppression. PMID:955676

Effect of thyroid hormone on the levels of erythrocyte carbonic anhydrase isozymes and 2,3-diphosphoglycerate in rabbits.

PubMed

Kondo, T; Taniguchi, N; Ishikawa, N; Ide, H; Takakuwa, E; Murao, M

1978-05-01

Levels of rabbit erythrocyte carbonic anhydrase B and C isozymes were determined in experimental hyperthyroidism using a quantitative immunologic technique. Levels of erythrocyte 2,3-diphosphoglycerate and protein binding iodine were simultaneously determined. Thyroxine and 3,5,3'-triiodothyronine were administered to rabbits orally for 30 days. A significant decrease in carbonic anhydrase B type was observed after 30 days, although no significant change was observed in carbonic anhydrase C type. These findings suggest that the steady state level of carbonic anhydrase B type in red cells is affected by thyroid hormone more readily than that of carbonic anhydrase C type. The level of red cell 2,3-diphosphoglycerate increased markedly after 10 days of treatment, corresponding to the increase of protein binding iodine. The clinical or pathologic significances were discussed in relation to the changes in the levels of these isozymes and 2,3-diphosphglycerate in red cells.

[THE FEATURES OF PHARMACOKINETICS ANTIBIOTIC CEFTRIAXONE WITH INTRAVENOUS WAY THAT ARE DEPOSITED IN AUTOLOGOUS ERYTHROCYTES AND LEUKOCYTES OF RABBIT].

PubMed

Yussifov, Z; Lokhvitskii, S; Gulyaev, A

2016-11-01

In the experiment on 18 rabbits Сeftriaxone pharmacokinetics after intravenous injection of the medication deposited in autologous erythrocytes and leukocytes were studied. The features of the pharmacokinetics when administered Сeftriaxone in erythrocytes ghost and leukocytes as compared to traditional intravenous drug administration have been determined.It is discussed the possibility of antibiotics transport in the surgical site of infection via cellular carriers in the article. We do the comparative analysis of the main pharmacokinetic parameters of Ceftriaxone in experimental conditions of leukocyte, erythrocyte transport and intravenous way. Based on these results the authors come to the conclusion about the benefits of leukocyte antibiotic transport to the site of surgical infection.

Serodiagnosis of infectious mononucleosis with a bovine erythrocyte glycoprotein.

PubMed

Fletcher, M A; Klimas, N G; Latif, Z A; Caldwell, K E

1983-09-01

A glycoprotein from bovine erythrocyte membrane was evaluated in two immunoassays as a reagent for the serodiagnosis of infectious mononucleosis (IM). We previously reported that a partially purified preparation of this glycoprotein, when attached to latex beads, agglutinated in the presence of IM heterophile antibody. In the present study, we used a highly purified form of the glycoprotein both as an agglutinating reagent, covalently bound to latex, and in a solid-phase sandwich-type radioimmunoassay (RIA) for IM antibody detection in a larger population of patients. We tested serum samples from college students with symptoms suggestive of IM with the latex reagent (143 samples) and with the RIA (245 samples). Correlation of these two tests, both with each other and with the classical differentially absorbed, agglutination tests for Paul-Bunnell antibody in IM sera, using fresh sheep or horse cells, was excellent (greater than 97% agreement). The new tests also corresponded in most cases with a rapid, unabsorbed preserved horse erythrocyte slide test. However, in this study of 245 samples, both apparent false-positives (5 samples) and apparent false-negatives (3 samples) were observed with this slide test. In conclusion, we found that the bovine glycoprotein as a reagent can facilitate the diagnosis of IM, giving results comparable to those with erythrocyte agglutination tests on differentially absorbed sera. The advantages are ease and speed of performance (latex test), potential for automation (RIA test), stability and uniformity of the glycoprotein reagent (latex and RIA tests), and most importantly, the ability to use unabsorbed sera (latex and RIA tests).

STUDIES ON THE ANTIGENIC PROPERTIES OF COMPLEMENT

PubMed Central

Klein, Paul G.; Burkholder, Peter M.

1960-01-01

Sheep erythrocytes sensitized with amboceptor and persensitized thereafter with guinea pig complement are agglutinated by rabbit anti-guinea pig globulin and by immune sera obtained by injection of rabbits with fixed complement. In this agglutination neither C'1 nor C'2 takes part. Fixed C'4 acts as an agglutinogen. An additional agglutinogen, distinct from C'4, was found on persensitized cells. This additional agglutinogen appears to be distinct from hemolytically active C'3. PMID:14409703

A scallop C-type lectin from Argopecten irradians (AiCTL5) with activities of lipopolysaccharide binding and Gram-negative bacteria agglutination.

PubMed

Mu, Changkao; Song, Xiaoyan; Zhao, Jianmin; Wang, Lingling; Qiu, Limei; Zhang, Huan; Zhou, Zhi; Wang, Mengqiang; Song, Linsheng; Wang, Chunlin

2012-05-01

C-type lectins are a family of calcium-dependent carbohydrate-binding proteins. In the present study, a C-type lectin (designated as AiCTL5) was identified and characterized from Argopecten irradians. The full-length cDNA of AiCTL5 was of 673 bp, containing a 5' untranslated region (UTR) of 24 bp, a 3' UTR of 130 bp with a poly (A) tail, and an open reading frame (ORF) of 519 bp encoding a polypeptide of 172 amino acids with a putative signal peptide of 17 amino acids. A C-type lectin-like domain (CRD) containing 6 conserved cysteines and a putative glycosylation sites were identified in the deduced amino acid sequence of AiCTL5. AiCTL5 shared 11%-27.5% identity with the previous reported C-type lectin from A. irradians. The cDNA fragment encoding the mature peptide of AiCTL5 was recombined into pET-21a (+) with a C-terminal hexa-histidine tag fused in-frame, and expressed in Escherichia coli Origami (DE3). The recombinant AiCTL5 (rAiCTL5) agglutinated Gram-negative E. coli TOP10F' and Listonella anguillarum, but did not agglutinate Gram-positive bacteria Bacillus thuringiensis and Micrococcus luteus, and the agglutination could be inhibited by EDTA, indicating that AiCTL5 was a Ca(2+)-dependent lectin. rAiCTL5 exhibited a significantly strong activity to bind LPS from E. coli, which conformed to the agglutinating activity toward Gram-negative bacteria. Moreover, rAiCTL5 also agglutinated rabbit erythrocytes. These results indicated that AiCTL5 could function as a pattern recognition receptor to protect bay scallop from Gram-negative bacterial infection, and also provide evidence to understand the structural and functional diverse of lectin. Copyright © 2012 Elsevier Ltd. All rights reserved.

Lambda-cyhalothrin-induced changes in oxidative stress biomarkers in rabbit erythrocytes and alleviation effect of some antioxidants.

PubMed

El-Demerdash, Fatma M

2007-04-01

Erythrocytes are a convenient model to understand the membrane oxidative damage induced by various xenobiotic-prooxidants. This study was designed to investigate (1) the possibility of lambda-cyhalothrin (LC), a type II pyrethroid, to induce oxidative stress response in rabbit erythrocytes in vitro and its effect on selected antioxidant enzymes and (2) the role of vitamin C (VC; 20mM) and vitamin E (VE; 2mM) in alleviating the cytotoxic effects of LC. Erythrocytes were divided into three groups. The first group, previously prepared erythrocytes was incubated for 4h at 37 degrees C with different concentrations (0, 0.1, 0.5, 1, 2.5, 5mM) of LC. The second and third groups were preincubated with VC or VE, respectively for 20 min and followed by LC incubation for 4h. Following in vitro exposure, LC caused a significant induction of oxidative damage in erythrocytes at different concentrations as evidenced by increased thiobarbituric acid reactive substances (TBARS) levels. However, a significant decrease in the content of sulfhydryl groups (SH-groups), and the activities of acetylcholinesterase (AChE), superoxide dismutase (SOD), catalase (CAT) and glutathione S-transferase (GST) were observed. The response was concentration dependent. VC or VE pretreated erythrocytes showed a significant protection against the cytotoxic effects induced by LC on the studied parameters. In conclusion, antioxidant vitamins especially VE could be able to ameliorate LC-induced oxidative stress by decreasing lipid peroxidation and altering antioxidant defense system in erythrocytes.

Use of RBC-O and S-MCV parameters of SYSMEX XE-2100 in a patient with RBC cold agglutination.

PubMed

Wang, Hong; Lu, Lin; Zhou, Yun; Liu, Jian; Qian, Min; Tang, Weiming; Jie, Zhang; Pan, Shiyang

2013-01-01

Sometimes EDTA blood of erythrocyte agglutination cannot be well resolved by incubation at 37 degrees C. In this case report, however, such a specimen was detected from a lymphoma patient at room temperature by using RBC-O and S-MCV parameters of the SYSMEX XE-2100 hematology analyzer. The specimen was diluted with 0.9% NaCL solution at 1:1 before measurement. HCT, MCV, and MCHC, corrected by RBC-O, HGB and S-MCV, were all in their normal ranges. This case indicates that RBC-O and S-MCV parameters of XE-2100 can be used in the routine blood examination of erythrocyte agglutination specimen at room temperature.

Avian P1 antigens inhibit agglutination mediated by P fimbriae of uropathogenic Escherichia coli.

PubMed Central

Johnson, J R; Swanson, J L; Neill, M A

1992-01-01

Whole egg white from pigeon, dove, and cockatiel eggs, as well as the ovomucoid fraction of pigeon egg white, exhibited strong P1 antigenic activities and inhibited agglutination of human P1 erythrocytes and of digalactoside-coated latex beads by P-fimbriated Escherichia coli strains. In contrast, chicken egg white exhibited only weak P1 antigenic activity and had little impact on P-fimbrial agglutination. These preparations did not affect hemagglutination by E. coli strains expressing mannose-resistant adhesins other than P fimbriae, i.e., Dr, F1845, and S adhesins. Human anti-P1 serum diminished the P-fimbrial inhibitory activities of pigeon egg white and pigeon ovomucoid. Pigeon ovomucoid was equipotent on a molar basis with globoside, and the pigeon, dove, and cockatiel egg white preparations were equipotent with each other in P-fimbrial inhibition. Incubation of p erythrocytes in whole egg whites or in pigeon ovomucoid did not render them agglutinable by P-fimbriated bacteria, whereas incubation in globoside did. These data demonstrate that whole egg whites (and their ovomucoid fraction) from members of the families Columbidae (pigeons and doves) and Psittacidae (parrots) specifically and potently inhibit P-fimbrial agglutination, probably by providing P1 antigen as a receptor for the P-fimbrial adhesin. Avian egg white preparations may facilitate adhesin characterization of wild-type uropathogenic strains and may useful in preventing upper urinary tract infections due to P-fimbriated E. coli. PMID:1346125

EFFECT OF IONIZING RADIATION OF THE HEMOLYSIS OF ERYTHROCYTES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Belousov, A.P.

1957-05-01

The saponin hemolysis method is a very effective way of determining the resistance of erythrocytes to radiolysis. The irradiation of rabbits with a dose of 700 r induces the formation of erythrocytes resistant to chemical hemolysis and the rapid disappearance from the blood stream of non-resistant ones. In the case of burns produced by boiling water, blood cell hemolysis is temporarily increased during a period of acute toxicosis. In rabbits irradiated with a dose of 1000 to 1300 r, intensive hemolysis of erythrocytes starts immediately and continues for up to 30 days. The appearance of resistant erythrocytes in the bloodmore » is preceded by a period of active hemopoiesis and the restoration of hemoglobin. Increased resistance of erythrocytes to saponin hemolysis has been observed in rabbits who suffered loss of blood and were subsequently irradiated. Irradiation of the blood in vitro in large doses, as contrasted to small doses, lowers the resistance of erythrocytes to chemical hemolysis. Changes in the resistance of erythrocytes to saponin hemolysis are conditioned by the direct action of radiation on the blood cells and the secondary effect of hemolysins. Thus, knowing the mechanism of the hemolysis of erythrocytes under the influence of ionizing radiation allows a better insight into the pathogenesis of radiation sickness and helps the development of protective means to prevent the onset of hemolysis. (auth)« less

Study of rabbit erythrocytes membrane solubilization by sucrose monomyristate using laurdan and phasor analysis.

PubMed

Günther, German; Herlax, Vanesa; Lillo, M Pilar; Sandoval-Altamirano, Catalina; Belmar, Libnny N; Sánchez, Susana A

2018-01-01

The study of surfactant and bio membranes interaction is particularly complex due to the diversity in lipid composition and the presence of proteins in natural membranes. Even more difficult is the study of this interaction in vivo since cellular damage may complicate the interpretation of the results, therefore for most of the studies in this field either artificial or model systems are used. One of the model system most used to study biomembranes are erythrocytes due to their relatively simple structure (they lack nuclei and organelles having only the plasma membrane), their convenient experimental manipulation and availability. In this context, we used rabbit erythrocytes as a model membrane and Laurdan (6-lauroyl-2-dimethylaminonaphthalene) as the fluorescent probe to study changes promoted in the membrane by the interaction with the sucrose monoester of myristic acid, β-d-fructofuranosyl-6-O-myristoyl-α-d-glucopyranoside (MMS). Surfactant and erythrocytes interaction was studied by measuring hemoglobin release and the changes in water content in the membrane sensed by Laurdan. Using two-photon excitation, three types of measurements were performed: Generalized Polarization (analyzed as average GP values), Fluorescence Lifetime Imaging, FLIM (analyzed using phasor plots) and Spectral imaging (analyzed using spectral phasor). Our data indicate that at sublytical concentration of surfactant (20μM MMS), there is a decrease of about 35% in erythrocytes size, without changes in Laurdan lifetime or emission spectra. We also demonstrate that as hemolysis progress, Laurdan lifetime increased due to the decrease in hemoglobin (strong quencher of Laurdan emission) content inside the erythrocytes. Under these conditions, Laurdan spectral phasor analyses can extract the information on the water content in the membrane in the presence of hemoglobin. Our results indicate an increase in membrane fluidity in presence of MMS. Copyright © 2017 Elsevier B.V. All rights

Effect of adrenaline on the response of erythrocyte 2,3-diphosphoglycerate in rabbits in vivo.

PubMed

Odje, O E; Ramsey, J M

1996-06-01

1. A 6 hr time-course response of erythrocyte 2,3-diphosphoglycerate was studied in rabbits following adrenaline administration. 2. Eight female New Zealand white rabbits weighing about 3.6 Kg each were injected intra-peritoneally with a total of 0.97 mg/kg of adrenaline (0.56 mg/kg at time 0 min and 0.41 mg/kg at time 0.5 hr), and the venous level of red blood cell (RBC) 2,3-DPG was monitored at 0 hr, 1 hr, 3 hr, and 6 hr, respectively. As controls, the level of 2,3-DPG was also monitored in these rabbits weeks prior to the experiment. 3. A significant (p < 0.05) rise in the mean level of 2.3-DPG (mumol.ml-1 RBC) was reached 3 hr after the initial injection of adrenaline, and the level returned to the preexposure level by the end of 6 hr. 4. It is speculated that adrenaline may be one of the contributors that increases the level of 2,3-DPG during the resting period following exhaustive exercise because this catecholamine has been reported to increase following this type of hypoxia.

Hybridoma cell agglutination as a novel test to detect circulating antigen of Schistosoma japonicum.

PubMed

Li, Yong-Long; Liu, Wenqi; Ruppel, Andreas

2003-01-01

We developed a serodiagnostic test which is based on the agglutination of hybridoma cells. In the presence of specific antigen, agglutination of the fixed and stained cells occurs and can be visualized in analogy to traditional erythrocyte agglutination. The procedures were developed with a murine cell line producing a monoclonal antibody against a schistosome gut protein and sera of patients and mice infected with Schistosoma japonicum. This test is capable of detecting circulating antigen during pre-patency in mice infected with 50 cercariae. Its sensitivity was high with acute schistosomiasis japonica (97%, n = 32) and moderate with chronic cases (75%, n = 57). No positive reactions were obtained with healthy persons (n = 78) or patients infected with other parasites (Chlonorchis sinensis, n = 20; Paragonimus westermani, n = 20; Plasmodium vivax, n = 10) or suffering from lupus erythomatodus (n = 5) or mononucleosis (n = 10).

Dielectric inspection of erythrocyte morphology.

PubMed

Hayashi, Yoshihito; Oshige, Ikuya; Katsumoto, Yoichi; Omori, Shinji; Yasuda, Akio; Asami, Koji

2008-05-21

We performed a systematic study of the sensitivity of dielectric spectroscopy to erythrocyte morphology. Namely, rabbit erythrocytes of four different shapes were prepared by precisely controlling the pH of the suspending medium, and their complex permittivities over the frequency range from 0.1 to 110 MHz were measured and analyzed. Their quantitative analysis shows that the characteristic frequency and the broadening parameter of the dielectric relaxation of interfacial polarization are highly specific to the erythrocyte shape, while they are insensitive to the cell volume fraction. Therefore, these two dielectric parameters can be used to differentiate erythrocytes of different shapes, if dielectric spectroscopy is applied to flow-cytometric inspection of single blood cells. In addition, we revealed the applicability and limitations of the analytical theory of interfacial polarization to explain the experimental permittivities of non-spherical erythrocytes.

Light-scattering analysis of ultrasonic wave's influence on the RBC agglutination in vitro

NASA Astrophysics Data System (ADS)

Doubrovski, Valeri A.; Dvoretski, Costanten N.

1999-04-01

Elastic light scattering is one of the most often used optical methods to analyze the cells agglutination reaction - the base of a great number of medical diagnostic test and biomedical investigations. The increase of the resolution of methods and apparatus towards the induced cells aggregation - the foundation of the reaction of agglutination, is quite an actual problem. The solution of this problem increases the reliability of the diagnostic test and gives an opportunity to achieve the diagnostic information in the cases when the traditional approaches do not lead to the diagnostic results. The attempt to increase the resolution of the immune reaction analyzer by means of ultrasonic waves action on the reagent mixture in vitro is taken in this paper. The RBC agglutination reaction which is usually used for the blood group type examination is chosen as an example of an object of the investigation. Different laser optical trains of the devices based on the turbidimetric and nephelometric methods and their combination are analyzed here. The influence of the ultrasonic wave time interval action and of the features of the sample preparation procedure on the resolution towards the agglutination process was investigated in this work. It is shown that the ultrasonic wave action on the reagent mixture leads to a large gain in the resolution of the device towards the RBC agglutination process. The experiments showed that the resolution of the device was enough to register the agglutination process even for the erythrocytes with weak agglutination ability when the reaction was invisible without ultrasonic action. It occurred that the diagnostic test time was more than by an order shortened due to the ultrasonic wave action. The optimal ultrasonic time interval action, the sample preparation technology and experimental technique were defined. The principle of the ultrasonic wave action on the cells agglutination process suggested here can be spread out on the immune

The Staphylococcus aureus ArlRS Two-Component System Is a Novel Regulator of Agglutination and Pathogenesis

PubMed Central

Walker, Jennifer N.; Crosby, Heidi A.; Spaulding, Adam R.; Salgado-Pabón, Wilmara; Malone, Cheryl L.; Rosenthal, Carolyn B.; Schlievert, Patrick M.; Boyd, Jeffrey M.; Horswill, Alexander R.

2013-01-01

Staphylococcus aureus is a prominent bacterial pathogen that is known to agglutinate in the presence of human plasma to form stable clumps. There is increasing evidence that agglutination aids S. aureus pathogenesis, but the mechanisms of this process remain to be fully elucidated. To better define this process, we developed both tube based and flow cytometry methods to monitor clumping in the presence of extracellular matrix proteins. We discovered that the ArlRS two-component system regulates the agglutination mechanism during exposure to human plasma or fibrinogen. Using divergent S. aureus strains, we demonstrated that arlRS mutants are unable to agglutinate, and this phenotype can be complemented. We found that the ebh gene, encoding the Giant Staphylococcal Surface Protein (GSSP), was up-regulated in an arlRS mutant. By introducing an ebh complete deletion into an arlRS mutant, agglutination was restored. To assess whether GSSP is the primary effector, a constitutive promoter was inserted upstream of the ebh gene on the chromosome in a wildtype strain, which prevented clump formation and demonstrated that GSSP has a negative impact on the agglutination mechanism. Due to the parallels of agglutination with infective endocarditis development, we assessed the phenotype of an arlRS mutant in a rabbit combined model of sepsis and endocarditis. In this model the arlRS mutant displayed a large defect in vegetation formation and pathogenesis, and this phenotype was partially restored by removing GSSP. Altogether, we have discovered that the ArlRS system controls a novel mechanism through which S. aureus regulates agglutination and pathogenesis. PMID:24367264

Studies on a Factor in Sweet Potato Root Which Agglutinates Spores of Ceratocystis fimbriata, Black Rot Fungus 1

PubMed Central

Kojime, Mineo; Kawakita, Kazuhito; Uritani, Ikuzo

1982-01-01

A factor which agglutinated the spores of Ceratocystis fimbriata in the presence of Ca2+ was purified from sweet potato (Ipomea batatas Lam cv. Norin[1]) root. Element composition of the purified factor was as follows; analysis found: C (29.8%), H (3.97%), O (65.34%), N (0.81%): calculated for C43H69O70N1: C (30.02%), H (4.01%), O (65.15%), N (0.81%). The factor was mainly composed of galacturonic acid (53% of dry weight) and contained arabinose, fucose, and unidentified component as minor components. The factor also agglutinated A-, B-, AB-, and O types of human erythrocytes to almost the same degree in the presence of Ca2+. The differential spore-agglutinating activity of the factor depended on the pH of the assay medium; it agglutinated similarly the germinated spores of sweet potato and coffee strains at pH 7.5 and 5.5, whereas it displayed a distinct differential agglutinating activity at pH 6.5. The factor was assayed for spore-agglutinating activity at pH 6.5, using the germinated and ungerminated spores of seven strains of C. fimbriata; sweet potato, coffee, prune, cacao, oak, taro, and almond strains. The factor agglutinated ungerminated spores of all seven strains similarly, although small differences were observed among strains. On the other hand, a clear differential agglutination was observed among the germinated spores of various strains; sweet potato and almond strains were highly insensitive in comparison with other strains. The growth of the agglutinated spores of C. fimbriata was inhibited. These results are discussed in relation to host-parasite specificity. Images PMID:16662232

[Blood clots in erythrocyte concentrates during transfusion].

PubMed

Wagner, T; Drexler, C; Kröll, W; Jüngling, G; Lanzer, G; Gabriel, C

2008-12-01

The presence of multiple blood clots in leucocyte-depleted erythrocyte concentrates during a transfusion gave rise to an investigation to find the exact cause. Determination of the various blood group systems was carried out using the gel centrifugation method and also the polymerase chain reaction (PCR) using sequence-specific primers. In addition the human leucocyte antigens (HLA) class 1 and class 2 markers were determined with molecular biological methods. The erythrocytes in the blood bags containing the blood clots showed a mixed-field agglutination in each blood group where the donor and recipient had different phenotypes. The HLA groups, however, could be solely attributed to the patient, since during the preparation of erythrocyte concentrates all leucocytes are removed and only very few residual cells containing DNA are present. To the best of our knowledge, this is the first detailed report on blood clots from patient blood in erythrocyte concentrates, which occurred during a transfusion. The retrograde filling of the blood bag with patient blood during the transfusion led to coagulation in the bag. Therefore, careful attention must be taken when dealing with stored blood and corresponding training must be regularly carried out.

Lectin activity in mycelial extracts of Fusarium species.

PubMed

Bhari, Ranjeeta; Kaur, Bhawanpreet; Singh, Ram S

2016-01-01

Lectins are non-immunogenic carbohydrate-recognizing proteins that bind to glycoproteins, glycolipids, or polysaccharides with high affinity and exhibit remarkable ability to agglutinate erythrocytes and other cells. In the present study, ten Fusarium species previously not explored for lectins were screened for the presence of lectin activity. Mycelial extracts of F. fujikuroi, F. beomiformii, F. begoniae, F. nisikadoi, F. anthophilum, F. incarnatum, and F. tabacinum manifested agglutination of rabbit erythrocytes. Neuraminidase treatment of rabbit erythrocytes increased lectin titers of F. nisikadoi and F. tabacinum extracts, whereas the protease treatment resulted in a significant decline in agglutination by most of the lectins. Results of hapten inhibition studies demonstrated unique carbohydrate specificity of Fusarium lectins toward O-acetyl sialic acids. Activity of the majority of Fusarium lectins exhibited binding affinity to d-ribose, l-fucose, d-glucose, l-arabinose, d-mannitol, d-galactosamine hydrochloride, d-galacturonic acid, N-acetyl-d-galactosamine, N-acetyl-neuraminic acid, 2-deoxy-d-ribose, fetuin, asialofetuin, and bovine submaxillary mucin. Melibiose and N-glycolyl neuraminic acid did not inhibit the activity of any of the Fusarium lectins. Mycelial extracts of F. begoniae, F. nisikadoi, F. anthophilum, and F. incarnatum interacted with most of the carbohydrates tested. F. fujikuroi and F. anthophilum extracts displayed strong interaction with starch. The expression of lectin activity as a function of culture age was investigated. Most species displayed lectin activity on the 7th day of cultivation, and it varied with progressing of culture age. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

Formation of 5-Oxoproline from Glutathione in Erythrocytes by the γ-Glutamyltranspeptidase-Cyclotransferase Pathway

PubMed Central

Palekar, Anil G.; Tate, Suresh S.; Meister, Alton

1974-01-01

γ-Glutamyltranspeptidase activity was demonstrated in the membrane fraction of rabbit erythrocytes. The activity observed (with glutathione and various amino-acid acceptors) was similar in magnitude to that of the γ-glutamylcyclotransferase and γ-glutamylcysteine synthetase activities found in the soluble fraction of the cell. No transpeptidase activity was observed with either γ-glutamyl p-nitroanilide or oxidized glutathione in contrast to the rabbit-kidney enzyme for which these compounds and glutathione serve as substrates. Erythrocyte suspensions and hemolysates formed 5-oxoproline (pyroglutamate; pyrrolidone carboxylate); the rate of 5-oxoproline formation from glutathione by hemolysates was increased by addition of methionine. The findings indicate that 5-oxoproline is an end-product of glutathione metabolism in erythrocytes, and that 5-oxoproline passes out of the erythrocyte and is metabolized in other tissues. The observed rate of 5-oxoproline formation is consistent with the conclusion that the γ-glutamyltranspeptidase-cyclotransferase pathway, together with the synthesis of glutathione from glycine, cysteine, and glutamate, account for a large fraction of the observed amino-acid turnover of erythrocyte glutathione. PMID:4150022

Anemia and mechanism of erythrocyte destruction in ducks with acute Leucocytozoon infections

USGS Publications Warehouse

Kocan, R.M.

1968-01-01

In the anemia which accompanies infection by Leucocytozoon simondi in Pekin ducks there was a far greater loss of erythrocytes than could be accounted for as a result of direct physical rupture by the parasite. Erythrocyte loss began at the same time the 1st parasites appeared in the blood and was severest just prior to maximum parasitemia. Blood replacement and parasite loss occurred simultaneously. Examination of the spleen and bone marrow revealed that erythrophagocytosis was not the cause of anemia as reported for infections of Plasmodium, Babesia and Anaplasma. An anti-erythrocyte (A-E) factor was found in the serum of acutely infected ducks which agglutinated and hemolyzed normal untreated duck erythrocytes as well as infected cells. This A-E factor appeared when the 1st red cell loss was detected and reached its maximum titer just prior to the greatest red cell loss. Titers of the A-E factor were determined using normal uninfected erythrocytes at temperatures between 4 and 42 C. Cells agglutinated below 25 C and hemolyzed at 37 and 42 C. These results indicated that the A-E factor could be responsible for loss of cells other than those which were infected and could thus produce an excess loss of red cells. Attempts to implicate the A-E factor as an autoantibody were all negative. The A-E factor was present in the gamma fraction of acute serum but no anamnestic response could be detected when recovered ducks were reinfected. Anemia was never as severe in reinfections as in primary infections. The A-E factor also never reached as high a titer and was removed from the circulation very rapidly in reinfected ducks. It is concluded that red cell loss in ducks with acute Leucocytozoon disease results from intravascular hemolysis rather than erythrophagocytosis. The A-E factor responsible for hemolysis is more likely a parasite product rather than autoantibody.

Structural relationships between human erythrocyte sialoglycoproteins beta and gamma and abnormal sialoglycoproteins found in certain rare human erythrocyte variants lacking the Gerbich blood-group antigen(s).

PubMed Central

Reid, M E; Anstee, D J; Tanner, M J; Ridgwell, K; Nurse, G T

1987-01-01

The human erythrocyte membrane sialoglycoproteins beta and gamma are important for the maintenance of the discoid shape of the normal erythrocyte. In this paper we show that the human erythrocyte sialoglycoproteins beta and gamma (hereafter called beta and gamma) are structurally related. Rabbit antisera produced against purified beta and beta 1 and rendered specific to the cytoplasmic portion of these proteins also react with the cytoplasmic portion of gamma. Some human anti-Gerbich (Ge) sera react with the extracellular portion of both beta and gamma. This reactivity is shown to be directed towards a common epitope on beta and gamma. However, most anti-Ge sera do not react with beta, but react with an extracellular epitope only present on gamma. All individuals who lack the Ge antigens lack beta and gamma. In some cases abnormal sialoglycoproteins are present in the erythrocytes, and these are shown to be structurally related to beta and gamma. Rabbit antisera raised against the purified abnormal sialoglycoprotein from a Ge-negative erythrocyte type reacted with the cytoplasmic portion of both beta and gamma. Unlike normal beta and gamma, the abnormal sialoglycoproteins found in Ge-negative erythrocytes migrate as a diffuse band on SDS/polyacrylamide-gel electrophoresis. Studies using endoglycosidases suggest that the diffuse nature of these bands results from carbohydrate heterogeneity and that the abnormal sialoglycoproteins contain N-glycosidically linked oligosaccharides with repeating lactosamine units. Such polylactosamine chains are not present on normal beta or gamma. Images Fig. 1. Fig. 2. Fig. 3. PMID:2444210

Chemical aspects of agglutinate formation - Relationships between agglutinate composition and the composition of the bulk soil. [lunar surface composition

NASA Technical Reports Server (NTRS)

Via, W. N.; Taylor, L. A.

1976-01-01

Attention is centered on the nature and intensity of geochemical fractionation accompanying agglutination of several size fractions of the immature Apollo-16 soil sample 67460, from North Ray Crater. The soil features coarse mean grain size about 150 microns, low (20 wt.%) magnetic agglutinate content, and a bimodal grain size distribution. The magnetic fraction included both agglutinates and magnetic non-agglutinates (glass-free microbreccias with 30-60 micron native FeNi grains hosted in a matrix of pyroxene, ilmenite, and olivine). The separation process residue contained nonmagnetic agglutinates with compositions near pure plagioclase. The magnetic agglutinate fraction appears selectively enriched in ferromagnesian elements to the partial exclusion of plagioclase elements. Agglutinate glass chemistry based solely on magnetic separation is deprecated on the basis of the results.

Age-Related Buildup of Humoral Immunity against Epitopes for Rosette Formation and Agglutination in African Areas of Malaria Endemicity

PubMed Central

Barragan, Antonio; Kremsner, Peter G.; Weiss, Walter; Wahlgren, Mats; Carlson, Johan

1998-01-01

In this report, we show an age-related buildup of agglutinating activity as well as serum activity against rosette formation in children living in areas of Kenya and Gabon where malaria is endemic. Sera from Kenyans in general exhibited a stronger and wider immune response toward the epitopes, probably reflecting a difference in transmission patterns between the two areas. Thus, our results indicate that repeated malaria attacks in areas of endemicity, and consequently exposure to different isolate-specific antigens, will elicit an antibody-mediated response eventually enabling recognition of the majority of rosetting and agglutinating antigens. The correlation between antirosetting and agglutinating capacity was poor in individual cases, indicating that the rosetting epitopes are only a minor part of the highly diverse surface-exposed antigens (mainly PfEMP1) on the surface of parasitized erythrocytes toward which antibodies may react. These data together with our previous findings that the protection against cerebral malaria correlates with presence of antirosetting antibodies shed new light on our understanding of the gradual acquisition of immunity toward severe complications of malarial infection which children reared in areas of endemicity attain. PMID:9746579

[Effect of a tissue oxygenator (almitrine + raubasine) on the metabolism of 2,3-diphosphoglycerate of rabbits submitted by hypoxia].

PubMed

Callis, A; Dorance, M; Magnan de Bornier, B

1980-01-01

In normoxic rabbits, the intravenous injection (1 mg/kg) of the product (almitrine + raubasine) do not modify the erythrocytic level of 2,3-DPG. But, after hypoxia (the rabbits being submitted to an oxygen pressure of 7,8 kPa during 20 minutes) the same dose of this product induce a durable rise of erythrocytic 2,3-DPG level which remain, 24 hours latter, + 15% above normal.

Seroprevalence of Toxoplasma gondii infection in domestic rabbits in Durango State, Mexico.

PubMed

Alvarado-Esquivel, Cosme; Alvarado-Esquivel, Domingo; Villena, I; Dubey, J P

2013-09-01

There is a lack of information concerning the seroprevalence of Toxoplasma gondii infection in rabbits in northern Mexico. Through a cross sectional study, antibodies to T. gondii were determined in 429 domestic rabbits in Durango State, Mexico using the modified agglutination test. Rabbits were raised in 29 properties in 6 municipalities. Overall, antibodies to T. gondii were found in 70 (16.3%) of 429 rabbits, with titers of 1:25 in 42, 1:50 in 19, 1:100 in 5, 1:200 in 3, and 1:800 in 1. Seropositive rabbits were found in 21 (72.4%) of 29 properties, including 16 of 21 homes, 4 of 5 farms, and 1 of 3 pet shops. This is the first study of T. gondii infection in rabbits in Durango, Mexico. Results indicate that infected rabbits are a potential source of T. gondii infection in humans in Durango State. Published by Elsevier B.V.

Agglutination of Helicobacter pylori coccoids by lectins

PubMed Central

Khin, Mar Mar; Hua, Jie Song; Ng, Han Cong; Wadström, Torkel; Ho, Bow

2000-01-01

AIM: To study the agglutination pattern of Helicobacter pylori coccoid and spiral forms. METHODS: Assays of agglutination and agglutination inhibition were applied using fifteen commercial lectins. RESULTS: Strong agglutination was observed with mannose-specific Concanavalin A (Con A), fucose-specific Tetragonolobus purpureas (Lotus A) and N-acetyl glucosamine-specific Triticum vulgaris (WGA) lectins. Mannose and fucose specific lectins were reactive with all strains of H. pylori coccoids as compared to the spirals. Specific carbohydrates, glycoproteins and mucin were shown to inhibit H. pylori lectin-agglutination reactions. Pre-treatment of the bacterial cells with formalin and sulphuric acid did not alter the agglutination patterns with lectins. However, sodium periodate treatment of bacterial cells were shown to inhibit agglutination reaction with Con A, Lotus A and WGA lectins. On the contrary, enzymatic treatment of coccoids and spirals did not show marked inhibition of H. pylori lectin agglutination. Interes tingly, heating of H. pylori cells at 60 °C for 1 h was shown to augment the agglutination with all of the lectins tested. CONCLUSION: The considerable differences in lectin agglutination patterns seen among the two differentiated forms of H. pylori might be attributable to the structural changes during the events of morphological transformation, resulting in exposing or masking some of the sugar residues on the cell surface. Possibility of various sugar residues on the cell wall of the coccoids may allow them to bind to different carbohydrate receptors on gastric mucus and epithelial cells. The coccoids with adherence characteristics like the spirals could aid in the pathogenic process of Helicobacter infection. This may probably lead to different clinical outcome of H. pylori associated gastroduodenal disease. PMID:11819557

Preliminary evaluation of a gel tube agglutination major cross-match method in dogs.

PubMed

Villarnovo, Dania; Burton, Shelley A; Horney, Barbara S; MacKenzie, Allan L; Vanderstichel, Raphaël

2016-09-01

A major cross-match gel tube test is available for use in dogs yet has not been clinically evaluated. This study compared cross-match results obtained using the gel tube and the standard tube methods for canine samples. Study 1 included 107 canine sample donor-recipient pairings cross-match tested with the RapidVet-H method gel tube test and compared results with the standard tube method. Additionally, 120 pairings using pooled sera containing anti-canine erythrocyte antibody at various concentrations were tested with leftover blood from a hospital population to assess sensitivity and specificity of the gel tube method in comparison with the standard method. The gel tube method had a good relative specificity of 96.1% in detecting lack of agglutination (compatibility) compared to the standard tube method. Agreement between the 2 methods was moderate. Nine of 107 pairings showed agglutination/incompatibility on either test, too few to allow reliable calculation of relative sensitivity. Fifty percent of the gel tube method results were difficult to interpret due to sample spreading in the reaction and/or negative control tubes. The RapidVet-H method agreed with the standard cross-match method on compatible samples, but detected incompatibility in some sample pairs that were compatible with the standard method. Evaluation using larger numbers of incompatible pairings is needed to assess diagnostic utility. The gel tube method results were difficult to categorize due to sample spreading. Weak agglutination reactions or other factors such as centrifuge model may be responsible. © 2016 American Society for Veterinary Clinical Pathology.

Electrophoretic mobilities of erythrocytes in various buffers

NASA Technical Reports Server (NTRS)

Plank, L. D.; Kunze, M. E.; Todd, P. W.

1985-01-01

The calibration of space flight equipment depends on a source of standard test particles, this test particle of choice is the fixed erythrocyte. Erythrocytes from different species have different electrophoretic mobilities. Electrophoretic mobility depends upon zeta potential, which, in turn depends upon ionic strength. Zeta potential decreases with increasing ionic strength, so cells have high electrophoretic mobility in space electrophoresis buffers than in typical physiological buffers. The electrophoretic mobilities of fixed human, rat, and rabbit erythrocytes in 0.145 M salt and buffers of varying ionic strength, temperature, and composition, to assess the effects of some of the unique combinations used in space buffers were characterized. Several effects were assessed: glycerol or DMSO (dimethylsulfoxide) were considered for use as cryoprotectants. The effect of these substances on erythrocyte electrophoretic mobility was examined. The choice of buffer depended upon cell mobility. Primary experiments with kidney cells established the choice of buffer and cryoprotectant. A nonstandard temperature of EPM in the suitable buffer was determined. A loss of ionic strength control occurs in the course of preparing columns for flight, the effects of small increases in ionic strength over the expected low values need to be evaluated.

Red cell surface changes in cold agglutination

PubMed Central

Salsbury, A. J.; Clarke, J. A.; Shand, W. S.

1968-01-01

Surface changes in red blood cells undergoing cold agglutination have been investigated using the Cambridge Stereoscan electron microscope. On incubation of red cells with a cold agglutinin of anti-I specificity at 4°C, circular shadows on the red cell membrane developed within 2 min. At the same time the membrane showed a granularity and processes began to develop on the surface. These processes increased in length, the processes of contiguous cells became interlinked and agglutination was complete after incubation of 1 hr. On warming an agglutinated specimen, the process was reversed with separation of red cells and retraction of the finger-like processes to yield discrete red cells of normal appearance. The addition of heparin in vivo prevented agglutination but did not inhibit surface changes completely. Complement appeared to play no part in the production of cold agglutination due to these antibodies or in the reversal of agglutination by warming. The significance of the surface changes described in relation to previous information on the mechanism of agglutination, has been discussed. ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6Fig. 7Fig. 8Fig. 9Fig. 10Fig. 11 PMID:5655472

Agglutination reactions of human leucocytes

PubMed Central

Schulz, Jeanette; Muller, Helga

1963-01-01

Agglutination tests with various sera and leucocytes from 58 leukaemic patients and 61 patients without leukaemia are reported. The agglutination of white blood cells by guinea-pig serum is of limited value in the diagnosis of leukaemia, though the test may be helpful in distinguishing leukaemia from other lymphomatous disorders. Leuco-autoagglutinins were demonstrated more frequently than expected. Eleven leukaemic and six non-leukaemic sera agglutinated autologous leucocytes. White blood cell agglutinins showed no apparent relationship to maturity or numbers of circulating leucocytes or to previous blood transfusions, x-irradiation, or therapy with antimetabolites. PMID:14044034

Incidence of diarrhea with antibiotics and the increase of clostridia in rabbits.

PubMed

Hara-Kudo, Y; Morishita, Y; Nagaoka, Y; Kasuga, F; Kumagai, S

1996-12-01

Rabbits were treated with a single intravenous injection of various antibiotics. More than 40 per cent of the animals showed diarrhea after being treated with sulbactam/cefoperazone, cefmetazole, clindamycin, piperacillin or aspoxicillin. Clostridium difficile was isolated from sulbactam/cefoperazone-treated diarrheic rabbits, with their cecal contents showing positive reaction in a latex agglutination test for C. difficile enterotoxin. However, 27 cefmetazole-induced diarrheic cases were not associated with C. difficile. Other enteropathogenic bacteria, such as Campylobacter spp., Bacillus cereus, enteropathogenic Escherichia coli, coagulase positive Staphylococcus aureus, Salmonella spp., Vibrio spp., Clostridium perfringens and Clostridium spiroforme, were not isolated from either of diarrheic rabbit. However, the counts of clostridia remarkably increased in the intestine of cefmetazole-associated diarrheic rabbits. This was ascribed to the overgrowth of Clostridium innocuum and Clostridium sporogenes. There were no remarkable differences in changes in other bacterial population between diarrheic and non-diarrheic rabbits.

Primary structure of the 175K Plasmodium falciparum erythrocyte binding antigen and identification of a peptide which elicits antibodies that inhibit malaria merozoite invasion.

PubMed

Sim, B K; Orlandi, P A; Haynes, J D; Klotz, F W; Carter, J M; Camus, D; Zegans, M E; Chulay, J D

1990-11-01

The Plasmodium falciparum gene encoding erythrocyte binding antigen-175 (EBA-175), a putative receptor for red cell invasion (Camus, D., and T. J. Hadley. 1985. Science (Wash. DC). 230:553-556.), has been isolated and characterized. DNA sequencing demonstrated a single open reading frame encoding a translation product of 1,435 amino acid residues. Peptides corresponding to regions on the deduced amino acid sequence predicted to be B cell epitopes were assessed for immunogenicity. Immunization of mice and rabbits with EBA-peptide 4, a synthetic peptide encompassing amino acid residues 1,062-1,103, produced antibodies that recognized P. falciparum merozoites in an indirect fluorescent antibody assay. When compared to sera from rabbits immunized with the same adjuvant and carrier protein, sera from rabbits immunized with EBA-peptide 4 inhibited merozoite invasion of erythrocytes in vitro by 80% at a 1:5 dilution. Furthermore, these sera inhibited the binding of purified, authentic EBA-175 to erythrocytes, suggesting that their activity in inhibiting merozoite invasion of erythrocytes is mediated by blocking the binding of EBA-175 to erythrocytes. Since the nucleotide sequence of EBA-peptide 4 is conserved among seven strains of P. falciparum from throughout the world (Sim, B. K. L. 1990. Mol. Biochem. Parasitol. 41:293-296.), these data identify a region of the protein that should be a focus of vaccine development efforts.

INFECTIOUS MYXOMATOSIS OF RABBITS

PubMed Central

Rivers, Thomas M.; Ward, S. M.

1937-01-01

From the results of the experiments described in this paper it is obvious that large amounts of elementary bodies of myxoma can be obtained in a relatively pure state by means of the methods used. Furthermore, it is evident that infectious myxomatosis is a viral disease in which elementary bodies of the same order of magnitude as vaccinal elementary bodies play a conspicuous rô1e in that they either represent the etiological agent or are intimately associated with it. The bodies are specifically agglutinated by antimyxoma serum and are agglutinated to a less extent by serum from rabbits convalescing from fibroma, a disease closely related to myxoma. In virus-free filtrates of emulsions prepared from infected skin there is a soluble precipitinogen or precipitinogens specific for the malady. Moreover, a specific precipitinogen or precipitinogens are demonstrable in virus-free serum of animals acutely ill as a result of extensive infection with myxoma virus. It is believed that this is the second viral disease, yellow fever (14) being the first, in which a specific soluble antigen free from virus has been found in the serum of ill animals. PMID:19870643

[Secondary immune blood transfusion shock in calves due to the donor immune erythrocyte isoantibodies].

PubMed

Golemanov, D

1980-01-01

Experiments were carried out on 2 cows, used as donors and 10 calves at the age from 1 to 6 months, taken in the experiment as recipients. The calves were made a blood-transfusion in a dose of 9 cm(3)/kg T. from donors whose serum contained immune erythroantibodies with a titer of 1:4--1:64, directed against their erythrocytes. The recipients had not had antibodies, directed against the donors' erythrocytes. For the purposes of the investigations were used a hemalitic test and an agglutination in a vidal test-tube. The post-transfusional immune reactions and complications observed were related to the hematransfusional shock as a result of a collision between the donor's immune isoerythroantibodies and their corresponding erythrocytic antigens in the recipients. This shock is of great practical value for transfusional hematology in calves. The immune isoerythroantibodies, built up after blood transfusion of immunized, in advance, donors, were formed in 60% of the cases on the 7th--9th days afer the blood-transfusion and disappeared from peripheral blood on the 30ieth day afterwards.

Characterization and antimicrobial activity of lectins from Penicillium sp.

PubMed

Singh, R S; Jain, P; Kaur, H P

2013-11-01

Ten Penicillium sp. were screened for lectin activity for occurrence of lectins. Mycelial extracts from submerged cultures of P. corylophilum, P. expansum and P. purpurogenum showed agglutination against human (A, B, AB and O), goat, sheep, pig and rabbit erythrocytes. Neuraminidase treatment to human blood- type O erythrocytes substantially increased their agglutinability by all the lectins as compared to untreated erythrocytes. Modification of erythrocyte surfaces by protease increased the lectin titre only of P. corylophilum with no effect on other two lectins. P. corylophilum and P. expansum displayed relatively lower titres in mycelial extracts prepared from agar plate cultures as compared to broth cultures. A panel of sugars was tested for inhibition of lectin activity. All the lectins were found to be specific for asialofetuin, bovine submaxillary mucin, porcine stomach mucin, chondroitin-6-sulphate, D-sucrose and D-glucose. P. corylophilum lectin was expressed (Titre 8) by 5 day old cultures, reaching its maximum level (Titre 32) upon 8 days of cultivation, thereafter declin in lectin activity was observed. P. purpurogenum lectin was expressed by 7-10 days old cultures, while in P. expansum maximum lectin activity was elaborated by 5-8 days old cultures. Lectin extracts from all the three species were found to possess antimicrobial activities. Lectin extracts from the three Penicillium species displayed antifungal activity and antibacterial activity against Gram-negative and Gram-positive bacterial strains.

[Response of Calliphora vicina larval hemocytes to abiotic and biotic foreign particles injection].

PubMed

Kind, T V

2012-01-01

Human erythrocytes injection into the body cavity of Calliphora vicina postfeeding larvae results to their fast binding by thrombocytoidal fragments with agglutinates formation. There were almost none sites of lysis and degradation of erythrocytes in agglutinates even after shape modification and strands generation. Exceptions are zones of agglutinates with juvenile hemocytes, where destruction of erythrocytes is seen. The sequential injection of erythrocytes and charcoal particles leads to charcoal adhesion at first to agglutinates periphery and later to more deep stratum of cytoplasm between the erythrocytes. Under such conditions agglutinate formation period is accompanied with morphology variations which do not influence the intensity of agglutinating reaction. Juvenile plasmatocytes phagocytized the charcoal particles regardless of their concentration and duration of previous contact with erythrocytes. When mixture of abiotic and biotic particles was injected into post feeding larvae, crythrocytes and charcoal generate independent aggregations in the range of separate agglutinates. At the same time plasmatocytes form nodules consisting of temporary cell aggregations covered with cores of non phagocytized charcoal particles. These data testified that presumably lectin receptors responsible for foreign biotic and abiotic particles recognition are very near but not identical for different types of hemocytes. They may be specifical (for plasmatocytes) or integrated to different parts of cellular membrane (in thrombocytoids).

Plasmodium vivax Invasion of Human Erythrocytes Inhibited by Antibodies Directed against the Duffy Binding Protein

PubMed Central

Grimberg, Brian T; Udomsangpetch, Rachanee; Xainli, Jia; McHenry, Amy; Panichakul, Tasanee; Sattabongkot, Jetsumon; Cui, Liwang; Bockarie, Moses; Chitnis, Chetan; Adams, John; Zimmerman, Peter A; King, Christopher L

2007-01-01

Background Plasmodium vivax invasion requires interaction between the human Duffy antigen on the surface of erythrocytes and the P. vivax Duffy binding protein (PvDBP) expressed by the parasite. Given that Duffy-negative individuals are resistant and that Duffy-negative heterozygotes show reduced susceptibility to blood-stage infection, we hypothesized that antibodies directed against region two of P. vivax Duffy binding protein (PvDBPII) would inhibit P. vivax invasion of human erythrocytes. Methods and Findings Using a recombinant region two of the P. vivax Duffy binding protein (rPvDBPII), polyclonal antibodies were generated from immunized rabbits and affinity purified from the pooled sera of 14 P. vivax–exposed Papua New Guineans. It was determined by ELISA and by flow cytometry, respectively, that both rabbit and human antibodies inhibited binding of rPvDBPII to the Duffy antigen N-terminal region and to Duffy-positive human erythrocytes. Additionally, using immunofluorescent microscopy, the antibodies were shown to attach to native PvDBP on the apical end of the P. vivax merozoite. In vitro invasion assays, using blood isolates from individuals in the Mae Sot district of Thailand, showed that addition of rabbit anti-PvDBPII Ab or serum (antibodies against, or serum containing antibodies against, region two of the Plasmodium vivax Duffy binding protein) (1:100) reduced the number of parasite invasions by up to 64%, while pooled PvDBPII antisera from P. vivax–exposed people reduced P. vivax invasion by up to 54%. Conclusions These results show, for what we believe to be the first time, that both rabbit and human antibodies directed against PvDBPII reduce invasion efficiency of wild P. vivax isolated from infected patients, and suggest that a PvDBP-based vaccine may reduce human blood-stage P. vivax infection. PMID:18092885

Purification of a PHA-like chitin-binding protein from Acacia farnesiana seeds: a time-dependent oligomerization protein.

PubMed

Santi-Gadelha, T; Rocha, B A M; Oliveira, C C; Aragão, K S; Marinho, E S; Gadelha, C A A; Toyama, M H; Pinto, V P T; Nagano, C S; Delatorre, P; Martins, J L; Galvani, F R; Sampaio, A H; Debray, H; Cavada, B S

2008-07-01

A lectin-like protein from the seeds of Acacia farnesiana was isolated from the albumin fraction, characterized, and sequenced by tandem mass spectrometry. The albumin fraction was extracted with 0.5 M NaCl, and the lectin-like protein of A. farnesiana (AFAL) was purified by ion-exchange chromatography (Mono-Q) followed by chromatofocusing. AFAL agglutinated rabbit erythrocytes and did not agglutinate human ABO erythrocytes either native or treated with proteolytic enzymes. In sodium dodecyl sulfate gel electrophoresis under reducing and nonreducing conditions, AFAL separated into two bands with a subunit molecular mass of 35 and 50 kDa. The homogeneity of purified protein was confirmed by chromatofocusing with a pI = 4.0 +/- 0.5. Molecular exclusion chromatography confirmed time-dependent oligomerization in AFAL, in accordance with mass spectrometry analysis, which confers an alteration in AFAL affinity for chitin. The protein sequence was obtained by a liquid chromatography quadrupole time-of-flight experiment and showed that AFAL has 68% and 63% sequence similarity with lectins of Phaseolus vulgaris and Dolichos biflorus, respectively.

Production of latex agglutination reagents for pneumococcal serotyping

PubMed Central

2013-01-01

Background The current ‘gold standard’ for serotyping pneumococci is the Quellung test. This technique is laborious and requires a certain level of training to correctly perform. Commercial pneumococcal latex agglutination serotyping reagents are available, but these are expensive. In-house production of latex agglutination reagents can be a cost-effective alternative to using commercially available reagents. This paper describes a method for the production and quality control (QC) of latex reagents, including problem solving recommendations, for pneumococcal serotyping. Results Here we describe a method for the production of latex agglutination reagents based on the passive adsorption of antibodies to latex particles. Sixty-five latex agglutination reagents were made using the PneuCarriage Project (PCP) method, of which 35 passed QC. The other 30 reagents failed QC due to auto-agglutination (n=2), no reactivity with target serotypes (n=8) or cross-reactivity with non-target serotypes (n=20). Dilution of antisera resulted in a further 27 reagents passing QC. The remaining three reagents passed QC when prepared without centrifugation and wash steps. Protein estimates indicated that latex reagents that failed QC when prepared using the PCP method passed when made with antiserum containing ≤ 500 μg/ml of protein. Sixty-one nasopharyngeal isolates were serotyped with our in-house latex agglutination reagents, with the results showing complete concordance with the Quellung reaction. Conclusions The method described here to produce latex agglutination reagents allows simple and efficient serotyping of pneumococci and may be applicable to latex agglutination reagents for typing or identification of other microorganisms. We recommend diluting antisera or removing centrifugation and wash steps for any latex reagents that fail QC. Our latex reagents are cost-effective, technically undemanding to prepare and remain stable for long periods of time, making them ideal for

The effects of erythrocyte deformability upon hematocrit assessed by the conductance method.

PubMed

Hayashi, Yoshihito; Katsumoto, Yoichi; Oshige, Ikuya; Omori, Shinji; Yasuda, Akio; Asami, Koji

2009-04-21

A comparative study of centrifugation and conductance methods for the estimation of cell volume fraction (phi) was performed to examine whether the strong forces exerted upon erythrocytes during centrifugation affect their volume, and the results are discussed in terms of erythrocyte deformability. Rabbit erythrocytes of four shapes (spherocytes, echinocytes, stomatocyte-like enlarged erythrocytes and discocytes) were prepared by controlling the pH of the suspending media. The packed cell volumes of the suspensions were measured by standard hematocrit determination methods using centrifugation in capillary tubes. Simultaneously, the same suspensions and their supernatants were used in dielectric spectroscopy measurements, and the low-frequency limits of their conductivities were used for the numerical estimation of phi. The hematocrit values of spherocytes and echinocytes were markedly less than the volume fractions obtained by the conductance method. Namely, the centrifugation reduced the cell volume. For enlarged erythrocytes and discocytes, however, the reduction of cell volume was not observed. These findings showed that phi obtained by the centrifugation method can be greatly affected by the deformability of the cells, but the level of the effect depends on the cell types. Consequently, phi obtained by the centrifugation method should be carefully interpreted.

Naturally occurring pepsin agglutinators in the serum of subhuman primates*

PubMed Central

Litwin, S. D.

1970-01-01

Antibodies directed against both human and infrahuman pepsin digested γ-globulin were present in a majority of the primate sera tested. The subhuman pepsin agglutinators paralleled previously described human pepsin agglutinators in respect to their wide distribution in normal sera, their specificity and cross-reactivity, and their immunochemical features. The pepsin agglutinators† at different primate levels appeared closely related. Among the subhuman pepsin agglutinators a subspecificity was described for a subhuman primate antigen. This finding suggested some limited differences between the subhuman pepsin agglutinators and the human pepsin agglutinators. Experimental immunization of four cynomologous monkeys failed to elicit or alter these serum reactants. PMID:4097824

Agglutinating mouse IgG3 compares favourably with IgMs in typing of the blood group B antigen: Functionality and stability studies

PubMed Central

Klaus, Tomasz; Bzowska, Monika; Kulesza, Małgorzata; Kabat, Agnieszka Martyna; Jemioła-Rzemińska, Małgorzata; Czaplicki, Dominik; Makuch, Krzysztof; Jucha, Jarosław; Karabasz, Alicja; Bereta, Joanna

2016-01-01

Mouse immunoglobulins M (IgMs) that recognize human blood group antigens induce haemagglutination and are used worldwide for diagnostic blood typing. Contrary to the current belief that IgGs are too small to simultaneously bind antigens on two different erythrocytes, we obtained agglutinating mouse IgG3 that recognized antigen B of the human ABO blood group system. Mouse IgG3 is an intriguing isotype that has the ability to form Fc-dependent oligomers. However, F(ab′)2 fragments of the IgG3 were sufficient to agglutinate type B red blood cells; therefore, IgG3-triggered agglutination did not require oligomerization. Molecular modelling indicated that mouse IgG3 has a larger range of Fab arms than other mouse IgG subclasses and that the unique properties of mouse IgG3 are likely due to the structure of its hinge region. With a focus on applications in diagnostics, we compared the stability of IgG3 and two IgMs in formulated blood typing reagents using an accelerated storage approach and differential scanning calorimetry. IgG3 was much more stable than IgMs. Interestingly, the rapid decrease in IgM activity was caused by aggregation of the molecules and a previously unknown posttranslational proteolytic processing of the μ heavy chain. Our data point to mouse IgG3 as a potent diagnostic tool. PMID:27484487

Antibody blocks acquisition of bacterial colonization through agglutination

PubMed Central

Roche, A. M.; Richard, A. L.; Rahkola, J. T.; Janoff, E. N.; Weiser, J. N.

2014-01-01

Invasive infection often begins with asymptomatic colonization of mucosal surfaces. A murine model of bacterial colonization with Streptococcus pneumoniae was used to study the mechanism for mucosal protection by immunoglobulin. In previously colonized immune mice, bacteria were rapidly sequestered within large aggregates in the nasal lumen. To further examine the role of bacterial agglutination in protection by specific antibodies, mice were passively immunized with IgG purified from anti-pneumococcal sera or pneumococcal type-specific monoclonal human IgA (hIgA1 or hIgA2). Systemically-delivered IgG accessed the mucosal surface and blocked acquisition of colonization and transmission between littermates. Optimal protection by IgG was independent of Fc fragment and complement and, therefore, did not involve an opsonophagocytic mechanism. Enzymatic digestion or reduction of IgG prior to administration showed that protection required divalent binding that maintained its agglutinating effect. Divalent hIgA1 is cleaved by the pneumococcal member of a family of bacterial proteases that generate monovalent Fabα fragments. Thus, passive immunization with hIgA1 blocked colonization by an IgA1-protease deficient mutant (agglutinated), but not the protease-producing wild-type parent (not agglutinated), whereas protease-resistant hIgA2 agglutinated and blocked colonization by both. Our findings highlight the importance of agglutinating antibodies in mucosal defense and reveal how successful pathogens evade this effect. PMID:24962092

EDTA-temperature-Induced pseudohematocytopenia in a patient with multiple myeloma.

PubMed

Zhang, Lixia; Pan, Shiyang; Zhang, Jie; Lu, Lin; Xie, Erfu; Ye, Qin

2012-01-01

Platelet clumping caused by ethylenediamine tetraacetic acid (EDTA) and erythrocyte agglutination caused by cold agglutinins are often found in clinical findings. However, erythrocyte agglutination induced by EDTA has not been reported as yet. Spurious low red blood cell (RBC), white blood cell (WBC), and platelet counts were observed in a patient blood sample collected in EDTA in vitro at room temperature and 37 degrees C. However, the phenomena were only observed in the sodium citrate and heparin anticoagulated blood at room temperature, but not at 37 degrees C. Both erythrocyte agglutination and platelet clumping were observed in the peripheral blood smear. These data suggest an EDTA-temperature-induced pseudohematocytopenia. It is a very rare phenomenon to observe erythrocyte agglutination induced by EDTA and temperature.

Weak "A" blood subgroup discrimination by a rheo-optical method: a new application of laser backscattering

NASA Astrophysics Data System (ADS)

Rasia, Rodolfo J.; Rasia-Valverde, Juana R.; Stoltz, Jean F.

1996-01-01

Laser backscattering is an excellent tool to investigate size and concentration of suspended particles. It was successfully applied to the analysis of erythrocyte aggregation. A method is proposed that applies laser backscattering to the evaluation of the strength of the immunologic erythrocyte agglutination by approaching the energy required for the mechanical dissociation of agglutinates. Mills and Snabre have proposed a theory of laser backscattering for erythrocyte aggregation analysis. It is applied here to analyze the dissociation process of erythrocyte agglutinates performed by imposing a constant shear rate to the agglutinate suspension in a couette viscometer until a dispersion of isolated red cells is attained. Experimental verifications of the method were performed on the erythrocytes of the ABO group reacting against an anti-A test serum in twofold series dilutions. Spent energy is approached by a numerical process carried out on the backscattered intensity data registered during mechanical dissociation. Velocities of agglutination and dissociation lead to the calculation of dissociation parameters These values are used to evaluate the strength of the immunological reaction and to discriminate weak subgroups of ABO system.

Simulation of Mechanical Behavior of Agglutinates

NASA Technical Reports Server (NTRS)

Nakagawa, Masami; Moon, Tae-Hyun

2005-01-01

Due to lack of "real" lunar soil or even lunar simulant, it is difficult to characterize the interaction between lunar soil (or simulant) with different surfaces that are involved in excavation and processing machinery. One unique feature possessed by lunar soil is the agglutinates produced by repeated high-speed micrometeoroid impacts and subsequent pulverization[l and 2]. The large particles are impacted by micrometeoroids [Fig.l] and pulverized to produce finer particles. This process continues until there are no more "large" particles left on the surface of the moon. Due to high impact speed, the impact melting process fuses fines to make agglutinates such as shown in Fig. 2. We will present a series of simulation results and movies will be shown to indicate brittle behavior of each individual agglutinate and also similar compressibility charts shown by Carrier et al. [3]. Fig. 3 shows our preliminary result of the simulated oedometer tests.

Discriminating the hemolytic risk of blood type A plasmas using the complement hemolysis using human erythrocytes (CHUHE) assay.

PubMed

Cunnion, Kenji M; Hair, Pamela S; Krishna, Neel K; Sass, Megan A; Enos, Clinton W; Whitley, Pamela H; Maes, Lanne Y; Goldberg, Corinne L

2017-03-01

The agglutination-based cross-matching method is sensitive for antibody binding to red blood cells but is only partially predictive of complement-mediated hemolysis, which is important in many acute hemolytic transfusion reactions. Here, we describe complement hemolysis using human erythrocytes (CHUHE) assays that directly evaluate complement-mediated hemolysis between individual serum-plasma and red blood cell combinations. The CHUHE assay is used to evaluate correlations between agglutination titers and complement-mediated hemolysis as well as the hemolytic potential of plasma from type A blood donors. Plasma or serum from each type A blood donor was incubated with AB or B red blood cells in the CHUHE assay and measured for free hemoglobin release. CHUHE assays for serum or plasma demonstrate a wide, dynamic range and high sensitivity for complement-mediated hemolysis for individual serum/plasma and red blood cell combinations. CHUHE results suggest that agglutination assays alone are only moderately predictive of complement-mediated hemolysis. CHUHE results also suggest that plasma from particular type A blood donors produce minimal complement-mediated hemolysis, whereas plasma from other type A blood donors produce moderate to high-level complement-mediated hemolysis, depending on the red blood cell donor. The current results indicate that the CHUHE assay can be used to assess complement-mediated hemolysis for plasma or serum from a type A blood donor, providing additional risk discrimination over agglutination titers alone. © 2016 AABB.

Measurement of RBC agglutination with microscopic cell image analysis in a microchannel chip.

PubMed

Cho, Chi Hyun; Kim, Ju Yeon; Nyeck, Agnes E; Lim, Chae Seung; Hur, Dae Sung; Chung, Chanil; Chang, Jun Keun; An, Seong Soo A; Shin, Sehyun

2014-01-01

Since Landsteiner's discovery of ABO blood groups, RBC agglutination has been one of the most important immunohematologic techniques for ABO and RhD blood groupings. The conventional RBC agglutination grading system for RhD blood typings relies on macroscopic reading, followed by the assignment of a grade ranging from (-) to (4+) to the degree of red blood cells clumping. However, with the new scoring method introduced in this report, microscopically captured cell images of agglutinated RBCs, placed in a microchannel chip, are used for analysis. Indeed, the cell images' pixel number first allows the differentiation of agglutinated and non-agglutinated red blood cells. Finally, the ratio of agglutinated RBCs per total RBC counts (CRAT) from 90 captured images is then calculated. During the trial, it was observed that the agglutinated group's CRAT was significantly higher (3.77-0.003) than that of the normal control (0). Based on these facts, it was established that the microchannel method was more suitable for the discrimination between agglutinated RBCs and non-agglutinated RhD negative, and thus more reliable for the grading of RBCs agglutination than the conventional method.

Rapid detection of hepatitis B virus surface antigen by an agglutination assay mediated by a bispecific diabody against both human erythrocytes and hepatitis B virus surface antigen.

PubMed

Chen, Yu-Ping; Qiao, Yuan-Yuan; Zhao, Xiao-Hang; Chen, Hong-Song; Wang, Yan; Wang, Zhuozhi

2007-06-01

Bispecific antibodies have immense potential for use in clinical applications. In the present study, a bispecific diabody against human red blood cells (RBCs) and hepatitis B virus surface antigen (HBsAg) was used to detect HBsAg in blood specimens. The bispecific diabody was constructed by crossing over the variable region of the heavy chains and the light chains of anti-RBC and anti-HBsAg antibodies with a short linker, SRGGGS. In enzyme-linked immunosorbent assays, this bispecific diabody showed specific binding to both RBCs and HBsAg. When this bispecific diabody was mixed with human blood specimens in the presence of HBsAg, the dual binding sites of the diabody caused agglutination of human RBCs. This diabody-mediated agglutination assay was then used to test 712 clinical blood specimens and showed 97.7% sensitivity and 100% specificity when the results were compared with those of the conventional immunoassay, which was used as a reference. This autologous RBC agglutination assay provides a simple approach for rapid screening for HBsAg in blood specimens.

Rapid Detection of Hepatitis B Virus Surface Antigen by an Agglutination Assay Mediated by a Bispecific Diabody against Both Human Erythrocytes and Hepatitis B Virus Surface Antigen▿

PubMed Central

Chen, Yu-Ping; Qiao, Yuan-Yuan; Zhao, Xiao-Hang; Chen, Hong-Song; Wang, Yan; Wang, Zhuozhi

2007-01-01

Bispecific antibodies have immense potential for use in clinical applications. In the present study, a bispecific diabody against human red blood cells (RBCs) and hepatitis B virus surface antigen (HBsAg) was used to detect HBsAg in blood specimens. The bispecific diabody was constructed by crossing over the variable region of the heavy chains and the light chains of anti-RBC and anti-HBsAg antibodies with a short linker, SRGGGS. In enzyme-linked immunosorbent assays, this bispecific diabody showed specific binding to both RBCs and HBsAg. When this bispecific diabody was mixed with human blood specimens in the presence of HBsAg, the dual binding sites of the diabody caused agglutination of human RBCs. This diabody-mediated agglutination assay was then used to test 712 clinical blood specimens and showed 97.7% sensitivity and 100% specificity when the results were compared with those of the conventional immunoassay, which was used as a reference. This autologous RBC agglutination assay provides a simple approach for rapid screening for HBsAg in blood specimens. PMID:17442848

Ultraviolet and visible light spectrophotometric approach to blood typing: objective analysis by agglutination index.

PubMed

Narayanan, S; Orton, S; Leparc, G F; Garcia-Rubio, L H; Potter, R L

1999-10-01

A new blood typing technology based on ultraviolet (UV) and visible light spectroscopy (UV/visible spectroscopy) has been developed. Blood groups and types are determined by quantifying reproducible changes in the UV and visible light spectra of blood in the presence of agglutinating antibodies. Samples of red cells in the presence and absence of agglutinating antibodies were examined by UV/visible spectroscopy. Blood groups and types were determined by comparing the optical density spectra obtained between 665 and 1000 nm. These comparisons generate numbers (agglutination index) ranging from 0 to 100, with smaller numbers corresponding to lack of agglutination and larger numbers corresponding to agglutination. The optical density of agglutinated blood is dramatically different from that of unagglutinated blood. The agglutination index derived from the relative slopes of the spectra is an objective indicator of agglutination strength. An agglutination index greater than 17 consistently and accurately established blood group- and type-specific agglutination. The method accurately predicted A, B, and O blood groups, and D type in over 275 samples. Scattering theory-based calculations of relative volumes of red cells before and after agglutination show a direct correlation with the agglutination index and provide the theoretical basis of the analysis. This quantitative technique is reproducible and has the potential for automation.

Binding of selected extracellular matrix proteins to enterococci and Streptococcus bovis of animal origin.

PubMed

Styriak, I; Lauková, A; Fallgren, C; Wadström, T

1999-12-01

Thirty-three enterococcal strains and 10 Streptococcus bovis strains were investigated for their protein-binding cell surface components. Seven extracellular matrix (ECM) proteins were immobilized on Difco latex beads to detect these components on the surface of all enterococcal strains and eight non-autoaggregating S. bovis strains by a particle agglutination assay (PAA). Twenty-three selected strains were also examined in microtiter plate assays. According to the absorbance readings (A(570nm)), 11 strains were classified as nonadherent (A(570nm) < 0.1), 10 strains as weakly adherent (0.1 < A(570nm) > 0.3), and 2 strains as strongly adherent (A(570nm) > 0.3) in these assays. A direct correlation was found between the values obtained in PAA and A(570nm) readings of microtiter plate assays. Binding of (125)I-labeled bovine lactoferrin to enterococci and streptococci was in the range of 6%-30% and of (125)I-labeled human vitronectin in the range of 9%-33% to streptococci. The binding of(125)I-labeled ECM proteins to selected strains was much more effectively inhibited by sulfated carbohydrates than by non-sulfated hyaluronic acid, indicating the importance of the sulfate groups of these inhibitors. An inhibition effect of heparin on bLf binding to four selected strains was higher in comparison with fucoidan in the microtiter plates. Thirty-five out of 44 strains had agglutinated rabbit erythrocytes. However, these strains showed no ability to agglutinate bovine or sheep erythrocytes.

Surgical management of vulvovaginal agglutination due to lichen planus.

PubMed

Fairchild, Pamela S; Haefner, Hope K

2016-02-01

Lichen planus is a rare dermatological disorder that is often associated with painful and disfiguring vulvovaginal effects. At the University of Michigan Center for Vulvar Diseases, we see many women with vulvovaginal lichen planus each year, with marked scarring and vulvovaginal agglutination that precludes vaginal intercourse and causes difficulty with urination. Through our experience, we developed a protocol for the operative management and postoperative care for severe vulvovaginal agglutination. Our objective is to share this protocol with a wider audience so that providers who see patients with these devastating effects of lichen planus can benefit from our experience to better serve this patient population. The figure represents a case of erosive lichen planus with early vaginal agglutination. The video reviews the pathophysiology and presentation of lichen planus. We then present a case of scarring and agglutination in a young woman, including our surgical management and postoperative care recommendations. Copyright © 2016 Elsevier Inc. All rights reserved.

Direct agglutination test for serologic diagnosis of Neospora caninum infection.

PubMed

Romand, S; Thulliez, P; Dubey, J P

1998-01-01

A direct agglutination test was evaluated for the detection and quantitation of IgG antibodies to Neospora caninum in both experimental and natural infections in various animal species. As compared with results obtained by the indirect fluorescent antibody test, the direct agglutination test appeared reliable for the serologic diagnosis of neosporosis in a variety of animal species. The direct agglutination test should provide easily available and inexpensive tools for serologic testing for antibodies to N. caninum in many host species.

Systems, devices, and methods for agglutination assays using sedimentation

DOEpatents

Schaff, Ulrich Y.; Sommer, Gregory J.; Singh, Anup K.

2016-01-26

Embodiments of the present invention include methods for conducting agglutination assays using sedimentation. Aggregates may be exposed to sedimentation forces and travel through a density medium to a detection area. Microfluidic devices, such as microfluidic disks, are described for conducting the agglutination assays, as are systems for conducting the assays.

[The incidence of agglutination and its influence on sperm quality and fertility of boar semen].

PubMed

Bollwein, Heinrich; Petschow, Karola; Weber, Frank; Leiding, Claus; Stolla, Rudolf

2004-01-01

The aim of this study was to examine the incidence of sperm agglutinations and their relationships with sperm quality and fertility. Semen samples of 40 boars of an AI-station were investigated. Nineteen of the 40 investigated boars showed a constantly low (< 10% agglutinated sperm), 3 an intermediate (10-20%) and 6 boars a high level (> 20%) of agglutination in raw semen. The degree of agglutination in sperm samples of 12 boars varied distinctly during the investigation period. During summer more (P < 0.05) agglutinated sperm were observed (11.0 +/- 11.6%) than during winter (6.2 +/- 7.3%). There was no association between bacterial contamination and incidence of agglutinations (P > 0.05). After dilution in extender the percentage of agglutinated sperm decreased from 6.2 +/- 7.3% to 1.1 +/- 1.4% (P < 0.0001). Twenty-four hours after dilution the percentage of progressively motile sperm was 7.4% lower (P < 0.05) in ejaculates with an initially high degree of agglutination (> 20% agglutinated sperm) compared to samples with an initially low degree of agglutinated sperm (< 10%). Plasma membrane integrity, mitochondrial membrane potential, acrosome reaction and chromatin structure were independent (P > 0.05) from the level of agglutination. Fertility data did not differ (P > 0.05) between boars with low and high numbers of agglutinated sperm in raw semen. The results show that there are individual, ejaculatory and seasonal variations in the incidence and degree of agglutination. Agglutinations have a negative effect on motility of sperm and disappear to a large extent after dilution in sperm extender. They have no negative consequences on fertility.

The specificity of Centruroides sculpturatus Ewing (Arizona lethal scorpion) hemolymph agglutinins.

PubMed

Vasta, G R; Cohen, E

1982-01-01

C. sculpturatus sera agglutinate human erythrocytes independently of the ABO blood group, enzyme treatment, incubation temperature or sex of the scorpions. Tested with human lymphocytes and reptile and bird erythrocytes, C. sculpturatus serum reacts like an anti-sialic acid agglutinin. With leukemic lymphocytes, titers are higher than with normal lymphocytes. Mammalian erythrocytes show characteristic agglutination patterns for C. sculpturatus for Limulus polyphemus (horseshoe crab) that suggest different receptors for agglutinins of both species. Cross absorption and elution experiments indicate the presence of at least two specific agglutinins in C. sculpturatus serum. Agglutination is inhibited by N-acetylneuraminic acid and N-glycolyneuraminic acid, for all erythrocytes tested. Calcium is required for optimal activity of C. sculpturatus agglutinins. C. sculpturatus agglutinating activity is destroyed at 65% degrees C for 20 minutes. Titers are decreased by 2-mercaptoethanol, and more so after alkylation with iodoacetic acid suggesting that disulfide bonds are present in C. sculpturatus agglutinin molecules.

Differential Lectin Agglutination of Fetal, Dividing-Postnatal, and Malignant Hepatocytes

PubMed Central

Becker, F. F.

1974-01-01

Numerous studies have reported the capacity of the lectin, concanavalin A, to agglutinate selected cell-types. The finding that cells transformed in culture, embryonic cells, and malignant cells are all agglutinated by this substance, may contribute to our understanding of the oncogenic process. The present study compared the response to concanavalin A of rat hepatocytes derived from livers of differing developmental and mitotic-status as well as those derived from malignant liver tumors (hepatomas). Fetal hepatocytes and hepatoma cells were highly susceptible to agglutination while hepatocytes from post-natal livers, whether dividing or quiescent, were not. Treatment with protease(s) did not make the interphase hepatocyte agglutinable. These data emphasize the importance of examining a wide variety of cells in attempting to understand the interaction of lectins on cell surfaces, and further, demonstrate the value of obtaining cells directly from tissue(s) during differing physiologic and pathologic states. Images PMID:4373708

V(H)H (nanobody) directed against human glycophorin A: a tool for autologous red cell agglutination assays.

PubMed

Habib, Ibrahim; Smolarek, Dorota; Hattab, Claude; Grodecka, Magdalena; Hassanzadeh-Ghassabeh, Gholamreza; Muyldermans, Serge; Sagan, Sandrine; Gutiérrez, Carlos; Laperche, Syria; Le-Van-Kim, Caroline; Aronovicz, Yves Colin; Wasniowska, Kazimiera; Gangnard, Stephane; Bertrand, Olivier

2013-07-01

The preparation of a V(H)H (nanobody) named IH4 that recognizes human glycophorin A (GPA) is described. IH4 was isolated by screening a library prepared from the lymphocytes of a dromedary immunized by human blood transfusion. Phage display and panning against GPA as the immobilized antigen allowed isolating this V(H)H. IH4, representing 67% of the retrieved V(H)H sequences, was expressed as a soluble correctly folded protein in SHuffle Escherichia coli cells, routinely yielding approximately 100 mg/L fermentation medium. Because IH4 recognizes GPA independently of the blood group antigens, it recognizes red cells of all humans with the possible exception of those with some extremely rare genetic background. The targeted linear epitope comprises the GPA Y52PPE55 sequence. Based on surface plasmon resonance results, the dissociation constant of the IH4-GPA equilibrium is 33 nM. IH4 is a stable protein with a transition melting temperature of 75.8 °C (measured by differential scanning calorimetry). As proof of concept, we fused HIV p24 to IH4 and used the purified construct expressed in E. coli to show that IH4 was amenable to the preparation of autologous erythrocyte agglutination reagents: reconstituted blood prepared with serum from an HIV-positive patient was readily agglutinated by the addition of the bifunctional reagent. Copyright © 2013 Elsevier Inc. All rights reserved.

A single Alal 39-to-Glu substitution in the Renibacterium salmoninarum virulence-associated protein p57 results in antigenic variation and is associated with enhanced p57 binding to Chinook salmon leukocytes

USGS Publications Warehouse

Wiens, Gregory D.; Pascho, Ron; Winton, James R.

2002-01-01

The gram-positive bacterium Renibacterium salmoninarum produces relatively large amounts of a 57-kDa protein (p57) implicated in the pathogenesis of salmonid bacterial kidney disease. Antigenic variation in p57 was identified by using monoclonal antibody 4C11, which exhibited severely decreased binding to R. salmoninarum strain 684 p57 and bound robustly to the p57 proteins of seven other R. salmoninarum strains. This difference in binding was not due to alterations in p57 synthesis, secretion, or bacterial cell association. The molecular basis of the 4C11 epitope loss was determined by amplifying and sequencing the two identical genes encoding p57, msa1 and msa2. The 5′ and coding sequences of the 684 msa1 and msa2 genes were identical to those of the ATCC 33209 msa1and msa2 genes except for a single C-to-A nucleotide mutation. This mutation was identified in both the msa1 and msa2 genes of strain 684 and resulted in an Ala139-to-Glu substitution in the amino-terminal region of p57. We examined whether this mutation in p57 altered salmonid leukocyte and rabbit erythrocyte binding activities. R. salmoninarum strain 684 extracellular protein exhibited a twofold increase in agglutinating activity for chinook salmon leukocytes and rabbit erythrocytes compared to the activity of the ATCC 33209 extracellular protein. A specific and quantitative p57 binding assay confirmed the increased binding activity of 684 p57. Monoclonal antibody 4C11 blocked the agglutinating activity of the ATCC 33209 extracellular protein but not the agglutinating activity of the 684 extracellular protein. These results indicate that the Ala139-to-Glu substitution altered immune recognition and was associated with enhanced biological activity of R. salmoninarum 684 p57.

A novel flow cytometry-based assay for the quantification of antibody-dependent pneumococcal agglutination

PubMed Central

van der Gaast—de Jongh, Christa E.; Diavatopoulos, Dimitri A.; de Jonge, Marien I.

2017-01-01

The respiratory pathogen Streptococcus pneumoniae is a major cause of diseases such as otitis media, pneumonia, sepsis and meningitis. The first step towards infection is colonization of the nasopharynx. Recently, it was shown that agglutinating antibodies play an important role in the prevention of mucosal colonization with S. pneumoniae. Here, we present a novel method to quantify antibody-dependent pneumococcal agglutination in a high-throughput manner using flow cytometry. We found that the concentration of agglutinating antibodies against pneumococcal capsule are directly correlated with changes in the size and complexity of bacterial aggregates, as measured by flow cytometry and confirmed by light microscopy. Using the increase in size, we determined the agglutination index. The cutoff value was set by measuring a series of non-agglutinating antibodies. With this method, we show that not only anti-polysaccharide capsule antibodies are able to induce agglutination but that also anti-PspA protein antibodies have agglutinating capabilities. In conclusion, we have described and validated a novel method to quantify pneumococcal agglutination, which can be used to screen sera from murine or human vaccination studies, in a high-throughput manner. PMID:28288168

Tube and column agglutination technology for autocontrol testing.

PubMed

Courtney, J E; Vincent, J L; Indrikovs, A J

2001-01-01

The incidence of positive autocontrol test results with column agglutination technology is a concern. This study investigates the incidence and significance of positive autocontrols in the ID Micro Typing System (gel) and the Gamma ReACT (ReACT). The study encompassed a total of 1021 randomly selected samples from patients and 95 samples from donors collected during 1 month. The autocontrol testing was carried out according to the manufacturer's instructions for the column agglutination tests. The tube method was carried out using low-ionic-strength solution (LISS). The direct antiglobulin test (DAT) was performed using the tube method, and further investigated with elution studies if warranted. Seventy-nine patient's samples (7.74%) had a positive autocontrol: the gel test, 72 (91.13%); ReACT, 21 (26.58%); and the tube method, 27 (34.18%). Of the 79 positive autocontrols, 44 samples had a negative DAT. Of the samples with positive DAT results, only one possessed a clinically significant antibody, anti-D. Moreover, the same sample also tested positive in all three methods. Column agglutination techniques have increased sensitivity for a positive autocontrol beyond the conventional tube method. However, ReACT and gel tests differ significantly in their frequency of positives. Investigation of the significance of a positive autocontrol in column agglutination technology when the conventional tube method is also positive is suggested.

Agglutination of intravenously administered phosphatidylcholine-containing lipid emulsions with serum C-reactive protein.

PubMed

Tugirimana, Pierrot; Speeckaert, Marijn M; Fiers, Tom; De Buyzere, Marc L; Kint, Jos; Benoit, Dominique; Delanghe, Joris R

2013-04-01

C-reactive protein (CRP) is able to bind phospholipids in the presence of calcium. We wanted to investigate the reaction of CRP with various commercial fat emulsions and to explore the impact of CRP agglutination on serum CRP levels. Serum specimens were mixed with Intralipid 20% (soybean oil-based fat emulsion), Structolipid (structured oil-based fat emulsion), Omegaven (fish oil-based fat emulsion), or SMOFlipid (mixed soybean oil-, olive oil-, and fish oil-based emulsion) in Tris-calcium buffer (pH 7.5). After 30 minutes of incubation at 37°C, CRP-phospholipid complexes were turbidimetrically quantified and flow cytometric analysis was performed. Similarly, CRP complexes were monitored in vivo, following administration of fat emulsion. CRP was able to agglutinate phospholipid-containing lipid droplets present in the soybean oil-based fat emulsion and the structured oil-based fat emulsion. To a lesser extent, agglutination was observed for fish oil-containing fat emulsions, whereas no agglutination was noticed for the mixed soybean oil-, olive oil-, and fish oil-based emulsion. Results for propofol-containing emulsions were comparable. Agglutination correlated with phospholipid content of the emulsions. When in vivo agglutination occurred, plasma CRP values dropped due to consumption of CRP by phospholipid-induced agglutination. In this in vitro experiment, we demonstrated agglutination of CRP with phospholipids in various fat emulsions. Research studies are required in patients to determine which effects occur with various intravenous fat emulsions.

9 CFR 147.1 - The standard tube agglutination test. 1

Code of Federal Regulations, 2014 CFR

2014-01-01

... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false The standard tube agglutination test. 1 147.1 Section 147.1 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... Blood Testing Procedures § 147.1 The standard tube agglutination test. 1 1 The procedure described is a...

9 CFR 147.1 - The standard tube agglutination test. 1

Code of Federal Regulations, 2011 CFR

2011-01-01

... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false The standard tube agglutination test. 1 147.1 Section 147.1 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... Blood Testing Procedures § 147.1 The standard tube agglutination test. 1 1 The procedure described is a...

9 CFR 147.1 - The standard tube agglutination test. 1

Code of Federal Regulations, 2013 CFR

2013-01-01

... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false The standard tube agglutination test. 1 147.1 Section 147.1 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... Blood Testing Procedures § 147.1 The standard tube agglutination test. 1 1 The procedure described is a...

9 CFR 147.1 - The standard tube agglutination test. 1

Code of Federal Regulations, 2010 CFR

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false The standard tube agglutination test. 1 147.1 Section 147.1 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... Blood Testing Procedures § 147.1 The standard tube agglutination test. 1 1 The procedure described is a...

9 CFR 147.1 - The standard tube agglutination test. 1

Code of Federal Regulations, 2012 CFR

2012-01-01

... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false The standard tube agglutination test. 1 147.1 Section 147.1 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... Blood Testing Procedures § 147.1 The standard tube agglutination test. 1 1 The procedure described is a...

Preventing Staphylococcus aureus Sepsis through the Inhibition of Its Agglutination in Blood

PubMed Central

McAdow, Molly; Kim, Hwan Keun; DeDent, Andrea C.; Hendrickx, Antoni P. A.; Schneewind, Olaf; Missiakas, Dominique M.

2011-01-01

Staphylococcus aureus infection is a frequent cause of sepsis in humans, a disease associated with high mortality and without specific intervention. When suspended in human or animal plasma, staphylococci are known to agglutinate, however the bacterial factors responsible for agglutination and their possible contribution to disease pathogenesis have not yet been revealed. Using a mouse model for S. aureus sepsis, we report here that staphylococcal agglutination in blood was associated with a lethal outcome of this disease. Three secreted products of staphylococci - coagulase (Coa), von Willebrand factor binding protein (vWbp) and clumping factor (ClfA) – were required for agglutination. Coa and vWbp activate prothrombin to cleave fibrinogen, whereas ClfA allowed staphylococci to associate with the resulting fibrin cables. All three virulence genes promoted the formation of thromboembolic lesions in heart tissues. S. aureus agglutination could be disrupted and the lethal outcome of sepsis could be prevented by combining dabigatran-etexilate treatment, which blocked Coa and vWbp activity, with antibodies specific for ClfA. Together these results suggest that the combined administration of direct thrombin inhibitors and ClfA-antibodies that block S. aureus agglutination with fibrin may be useful for the prevention of staphylococcal sepsis in humans. PMID:22028651

Preventing Staphylococcus aureus sepsis through the inhibition of its agglutination in blood.

PubMed

McAdow, Molly; Kim, Hwan Keun; Dedent, Andrea C; Hendrickx, Antoni P A; Schneewind, Olaf; Missiakas, Dominique M

2011-10-01

Staphylococcus aureus infection is a frequent cause of sepsis in humans, a disease associated with high mortality and without specific intervention. When suspended in human or animal plasma, staphylococci are known to agglutinate, however the bacterial factors responsible for agglutination and their possible contribution to disease pathogenesis have not yet been revealed. Using a mouse model for S. aureus sepsis, we report here that staphylococcal agglutination in blood was associated with a lethal outcome of this disease. Three secreted products of staphylococci--coagulase (Coa), von Willebrand factor binding protein (vWbp) and clumping factor (ClfA)--were required for agglutination. Coa and vWbp activate prothrombin to cleave fibrinogen, whereas ClfA allowed staphylococci to associate with the resulting fibrin cables. All three virulence genes promoted the formation of thromboembolic lesions in heart tissues. S. aureus agglutination could be disrupted and the lethal outcome of sepsis could be prevented by combining dabigatran-etexilate treatment, which blocked Coa and vWbp activity, with antibodies specific for ClfA. Together these results suggest that the combined administration of direct thrombin inhibitors and ClfA-antibodies that block S. aureus agglutination with fibrin may be useful for the prevention of staphylococcal sepsis in humans.

Haemagglutination and surface structures in strains of Clostridium spiroforme.

PubMed

Baldassarri, L; Pantosti, A; Caprioli, A; Mastrantonio, P; Donelli, G

1989-07-01

Five strains of Clostridium spiroforme were examined for their surface properties. All strains were able to agglutinate human erythrocytes. Electron microscopy showed a ruthenium red-positive capsule mediating the attachment of bacteria to erythrocytes. Two strains, showing the lowest degree of haemagglutination, exhibited an additional external layer of filamentous structures, possibly interfering with the agglutinating activity. In spite of their agglutinating ability, the C. spiroforme strains did not show surface hydrophobicity, thus suggesting the possible existence of a new type of clostridial adhesin.

Comparison of gel column, card, and cartridge techniques for dog erythrocyte antigen 1.1 blood typing

PubMed Central

Seth, Mayank; Jackson, Karen V.; Winzelberg, Sarah; Giger, Urs

2012-01-01

Objective To compare accuracy and ease of use of a card agglutination assay, an immunochromatographic cartridge method, and a gel-based method for canine blood typing. Sample Blood samples from 52 healthy blood donor dogs, 10 dogs with immune-mediated hemolytic anemia (IMHA), and 29 dogs with other diseases. Procedures Blood samples were tested in accordance with manufacturer guidelines. Samples with low PCVs were created by the addition of autologous plasma to separately assess the effects of anemia on test results. Results Compared with a composite reference standard of agreement between 2 methods, the gel-based method was found to be 100% accurate. The card agglutination assay was 89% to 91% accurate, depending on test interpretation, and the immunochromatographic cartridge method was 93% accurate but 100% specific. Errors were observed more frequently in samples from diseased dogs, particularly those with IMHA. In the presence of persistent autoagglutination, dog erythrocyte antigen (DEA) 1.1 typing was not possible, except with the immunochromatographic cartridge method. Conclusions and Clinical Relevance The card agglutination assay and immunochromatographic cartridge method, performed by trained personnel, were suitable for in-clinic emergency DEA 1.1 blood typing. There may be errors, particularly for samples from dogs with IMHA, and the immunochromatographic cartridge method may have an advantage of allowing typing of samples with persistent autoagglutination. The laboratory gel-based method would be preferred for routine DEA 1.1 typing of donors and patients if it is available and time permits. Current DEA 1.1 typing techniques appear to be appropriately standardized and easy to use. PMID:22280380

Evolution of Shock Melt Compositions in Lunar Agglutinates

NASA Technical Reports Server (NTRS)

Vance, A. M.; Christoffersen, R.; Keller, L. P.

2015-01-01

Lunar agglutinates are aggregates of regolith grains fused together in a glassy matrix of shock melt produced during smaller-scale (mostly micrometeorite) impacts. Agglutinate formation is a key space weathering process under which the optically-active component of nanophase metallic Fe (npFe(sup 0)) is added to the lunar regolith. Here we have used energy-dispersive X-ray (EDX) compositional spectrum imaging in the SEM to quantify the chemical homogeneity of agglutinitic glass, correlate its homogeneity to its parent soil maturity, and identify the principle chemical components contributing to the shock melt compositional variations.

Agglutinates as recorders of regolith evolution - Application to the Apollo 17 drill core

NASA Technical Reports Server (NTRS)

Laul, J. C.; Smith, M. R.; Papike, J. J.; Simon, S. B.

1984-01-01

Chemical data are reported for agglutinates from 26 depth intervals of the Apollo 17 deep drill core, and the compositions of the agglutinates are compared with those of the soils in which they occur. The agglutinate sequence suggests a scenario in which several closely-spaced depositional events were involved in the formation of the drill core, rather than a continuous accumulation process.

Agglutinates as recorders of regolith evolution - Application to the Apollo 17 drill core

DOE Office of Scientific and Technical Information (OSTI.GOV)

Laul, J.C.; Smith, M.R.

1984-11-15

Chemical data are reported for agglutinates from 26 depth intervals of the Apollo 17 deep drill core, and the compositions of the agglutinates are compared with those of the soils in which they occur. The agglutinate sequence suggests a scenario in which several closely-spaced depositional events were involved in the formation of the drill core, rather than a continuous accumulation process.

Prevalence of naturally occurring antibodies against dog erythrocyte antigen 7 in a population of dog erythrocyte antigen 7-negative dogs from Spain and Italy.

PubMed

Spada, Eva; Proverbio, Daniela; Viñals Flórez, Luis Miguel; Del Rosario Perlado Chamizo, Maria; Serra Y Gómez de la Serna, Blanca; Perego, Roberta; Baggiani, Luciana

2016-08-01

OBJECTIVE To determine the prevalence of naturally occurring anti-dog erythrocyte antigen (DEA) 7 antibodies in DEA 7-negative dogs from Spain and Italy. ANIMALS 252 DEA 7-negative dogs from a population of 312 dogs that were previously tested for DEA 1, DEA 4, and DEA 7. PROCEDURES A plasma sample was obtained from each dog and evaluated for anti-DEA 7 antibodies by the use of gel column agglutination. Each plasma sample underwent major crossmatching with RBCs from DEA 7-positive dogs. Samples that resulted in agglutination were then crossmatched with RBCs from DEA 1-negative, DEA 4-positive, and DEA 7-negative dogs to confirm the presence of anti-DEA 7 antibodies. Results were then used to calculate the risk for a delayed transfusion reaction in a DEA 7-negative dog with anti-DEA 7 antibodies after a transfusion with blood that was not crossmatched or typed for DEA 7. RESULTS 96 of 252 (38.1%) plasma samples contained anti-DEA 7 antibodies. A DEA 7-negative dog with anti-DEA 7 antibodies had a 5.9% chance of developing a delayed hemolytic reaction after transfusion with blood not crossmatched or typed for DEA 7. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that canine blood used for transfusion should be crossmatched with the blood or plasma of the intended recipient prior to transfusion to minimize the likelihood that the recipient will develop a hemolytic reaction associated with anti-DEA 7 antibodies. Ideal canine blood donors should be negative for both DEA 1 and DEA 7.

Identification of cytosolic phosphodiesterases in the erythrocyte: A possible role for PDE5

PubMed Central

Adderley, Shaquria P.; Thuet, Kelly M.; Sridharan, Meera; Bowles, Elizabeth A.; Stephenson, Alan H.; Ellsworth, Mary L.; Sprague, Randy S.

2011-01-01

Summary Background Within erythrocytes (RBCs), cAMP levels are regulated by phosphodiesterases (PDEs). Increases in cAMP and ATP release associated with activation of β-adrenergic receptors (βARs) and prostacyclin receptors (IPRs) are regulated by PDEs 2, 4 and PDE 3, respectively. Here we establish the presence of cytosolic PDEs in RBCs and determine a role for PDE5 in regulating levels of cGMP. Material/Methods Purified cytosolic proteins were obtained from isolated human RBCs and western analysis was performed using antibodies against PDEs 3A, 4 and 5. Rabbit RBCs were incubated with dbcGMP, a cGMP analog, to determine the effect of cGMP on cAMP levels. To determine if cGMP affects receptor-mediated increases in cAMP, rabbit RBCs were incubated with dbcGMP prior to addition of isoproterenol (ISO), a βAR receptor agonist. To demonstrate that endogenous cGMP produces the same effect, rabbit and human RBCs were incubated with SpNONOate (SpNO), a nitric oxide donor, and YC1, a direct activator of soluble guanylyl cyclase (sGC), in the absence and presence of a selective PDE5 inhibitor, zaprinast (ZAP). Results Western analysis identified PDEs 3A, 4D and 5A. dbcGMP produced a concentration dependent increase in cAMP and ISO-induced increases in cAMP were potentiated by dbcGMP. In addition, incubation with YC1 and SpNO in the presence of ZAP potentiated βAR-induced increases in cAMP. Conclusions PDEs 2, 3A and 5 are present in the cytosol of human RBCs. PDE5 activity in RBCs regulates cGMP levels. Increases in intracellular cGMP augment cAMP levels. These studies suggest a novel role for PDE5 in erythrocytes. PMID:21525805

Identification of a human erythrocyte receptor for colonization factor antigen I pili expressed by H10407 enterotoxigenic Escherichia coli.

PubMed Central

Pieroni, P; Worobec, E A; Paranchych, W; Armstrong, G D

1988-01-01

We have identified a receptor for colonization factor antigen I (CFA/I) pili in human erythrocyte membranes. Erythrocyte binding assays, using whole organisms, suggested that the CFA/I receptor was a glycoprotein containing important sialic acid moieties. Subsequently, human erythrocyte membranes were extracted with lithium diiodosalicylate to obtain a soluble glycoprotein fraction from which to isolate receptors. The extracted material caused agglutination of the CFA/I+ but not the CFA/I- organisms at a protein concentration of 0.5 mg/ml. The CFA/I receptor was identified in iodinated extract by an affinity isolation procedure, using whole bacterial cells. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and autoradiography of the washed, extract-coated H10407 CFA/I+ organisms revealed a band with an apparent molecular weight of 26,000 which was present in the original extract but was not observed on extract-coated H10407 CFA/I- bacteria. The addition of purified CFA/I pili reduced binding of the 26,000-molecular-weight receptor to CFA/I+ bacteria. The CFA/I-specific receptor species also bound to wheat germ agglutinin-agarose. This observation supported the suggestion that the CFA/I receptor identified in this report is a sialoglycoprotein. Images PMID:2895745

Alpha Hemolysin Induces an Increase of Erythrocytes Calcium: A FLIM 2-Photon Phasor Analysis Approach

PubMed Central

Sanchez, Susana; Bakás, Laura; Gratton, Enrico; Herlax, Vanesa

2011-01-01

α-hemolysin (HlyA) from Escherichia coli is considered as the prototype of a family of toxins called RTX (repeat in toxin), a group of proteins that share genetic and structural features. HlyA is an important virulence factor in E. coli extraintestinal infections, such as meningitis, septicemia and urinary infections. High concentrations of the toxin cause the lysis of several cells such as erythrocytes, granulocytes, monocytes, endothelial and renal epithelial cells of different species. At low concentrations it induces the production of cytokines and apoptosis. Since many of the subcytolytic effects in other cells have been reported to be triggered by the increase of intracellular calcium, we followed the calcium concentration inside the erythrocytes while incubating with sublytic concentrations of HlyA. Calcium concentration was monitored using the calcium indicator Green 1, 2-photon excitation, and fluorescence lifetime imaging microscopy (FLIM). Data were analyzed using the phasor representation. In this report, we present evidence that, at sublytic concentrations, HlyA induces an increase of calcium concentration in rabbit erythrocytes in the first 10 s. Results are discussed in relation to the difficulties of measuring calcium concentrations in erythrocytes where hemoglobin is present, the contribution of the background and the heterogeneity of the response observed in individual cells. PMID:21698153

Typing of Haemophilus influenzae by Coagglutination and Conventional Slide Agglutination

PubMed Central

Shively, Roxanne G.; Shigel, Janet T.; Peterson, Ellena M.; De La Maza, Luis M.

1981-01-01

Coagglutination was compared with conventional slide agglutination for the typing of 297 clinical isolates of Haemophilus sp. A 100% correlation was found with the H. influenzae type b isolates. Coagglutination showed no false-positive reactions with the nontypable strains of H. influenzae and H. parainfluenzae isolates; however, conventional slide agglutination exhibited many false-positive and non-interpretable reactions. PMID:6977555

Erythrocyte permeability to urea and water: comparative study in rodents, ruminants, carnivores, humans, and birds.

PubMed

Liu, Lifeng; Lei, Tianluo; Bankir, Lise; Zhao, Dan; Gai, Xiaodong; Zhao, Xuejian; Yang, Baoxue

2011-01-01

Mammalian erythrocytes exhibit high urea permeability (P (urea)) due to UT-B expression in their cytoplasmic membrane. This high P (urea) allows fast equilibration of urea in erythrocytes during their transit in the hyperosmotic renal medulla. It also allows more urea (in addition to that in plasma) to participate in counter-current exchange between ascending and descending vasa recta, thus improving the trapping of urea in the medulla and improving urine concentrating ability. To determine if P (urea) in erythrocytes is related to diet and urine concentrating ability, we measured P (urea) in erythrocytes from 11 different mammals and 5 birds using stopped-flow light scattering. Carnivores (dog, fox, cat) exhibited high P (urea) (in x10(-5) cm/s, 5.3 ± 0.6, 3.8 ± 0.5 and 2.8 ± 0.7, respectively). In contrast, herbivores (cow, donkey, sheep) showed much lower P (urea) (0.8 ± 0.2, 0.7 ± 0.2, 1.0 ± 0.1, respectively). Erythrocyte P (urea) in human (1.1 ± 0.2), and pig (1.5 ± 0.1), the two omnivores, was intermediate. Rodents and lagomorphs (mouse, rat, rabbit) had P (urea) intermediate between carnivores and omnivores (3.3 ± 0.4, 2.5 ± 0.3 and 2.4 ± 0.3, respectively). Birds that do not excrete urea and do not express UT-B in their erythrocytes had very low values (<0.1 × 10(-5) cm/s). In contrast to P (urea), water permeability, measured simultaneously, was relatively similar in all mammals. The species differences in erythrocytes P (urea) most probably reflect adaptation to the different types of diet and resulting different needs for concentrating urea in the urine.

Passive immunization with Leptospira LPS-specific agglutinating but not non-agglutinating monoclonal antibodies protect guinea pigs from fatal pulmonary hemorrhages induced by serovar Copenhageni challenge.

PubMed

Challa, Sreerupa; Nally, Jarlath E; Jones, Carroll; Sheoran, Abhineet S

2011-06-15

Leptospira interrogans serovar Copenhageni causes pulmonary hemorrhages with respiratory failure, a major cause of death in leptospirosis patients. Protective immunity to Leptospira is known to correlate with the production of leptospiral lipopolysaccharide (L-LPS)-specific agglutinating antibodies. We generated L-LPS-specific mouse monoclonal antibodies (MAbs) and investigated if these MAbs can protect guinea pigs against fatal pulmonary hemorrhages caused by serovar Copenhageni. The MAbs L8H4 and L9B11 against 22kDa L-LPS agglutinated leptospires and completely protected guinea pigs from the development of fatal pulmonary hemorrhages by serovar Copenhageni, whereas the MAb L4C1 against 8kDa L-LPS neither agglutinated the bacteria nor protected the animals against the fatal pulmonary hemorrhages. Copyright © 2011 Elsevier Ltd. All rights reserved.

An integrated fiberoptic-microfluidic device for agglutination detection and blood typing.

PubMed

Ramasubramanian, Melur K; Alexander, Stewart P

2009-02-01

In this paper, an integrated fiberoptic-microfluidic device for the detection of agglutination for blood type cross-matching has been described. The device consists of a straight microfluidic channel through with a reacted RBC suspension is pumped with the help of a syringe pump. The flow intersects an optical path created by an emitter-received fiber optic pair integrated into the microfluidic device. A 650 nm laser diode is used as the light source and a silicon photodiode is used to detect the light intensity. The spacing between the tips of the two optic fibers can be adjusted. When fiber spacing is large and the concentration of the suspension is high, scattering phenomenon becomes the dominant mechanism for agglutination detection while at low concentrations and small spacing, optointerruption becomes the dominant mechanism. An agglutination strength factor (ASF) is calculated from the data. Studies with a variety of blood types indicate that the sensing method correctly identifies the agglutination reaction in all cases. A disposable integrated device can be designed for future implementation of the method for near-bedside pre-transfusion check.

Studies of the antibody nature of the rheumatoid factor

PubMed Central

Aho, K.; Harboe, M.; Leikola, J.

1964-01-01

The reaction of the rheumatoid factor (RF) with 7S γ-globulin antibodies of nine persons immunized with sheep erythrocytes was studied. All of a panel of rheumatoid sera with high Waaler-Rose titres agglutinated sheep cells sensitized with the human anti-sheep cell antibodies and O Rh positive cells sensitized with the `diagnostic' anti-CD serum Ripley. The RF measurable with these systems could be absorbed to diphtheria toxoid—human antitoxin precipitate, whereas the absorption with egg albumin—rabbit anti-egg albumin precipitate did not result in any appreciable titre reduction. However, the eluate from the rabbit precipitate was highly active in these systems, whereas Rh positive cells sensitized with anti-Rh sera suitable for Gm(a) typing were not regularly agglutinated. A markedly greater concentration of native than of heat-aggregated γ-globulin was needed for inhibition of the agglutination by the RF of cells heavily sensitized with the human anti-sheep cell antibodies. No appreciable difference in this respect was seen when using lightly sensitized cells. Only the heavily sensitized cells fixed complement. The `natural' 7S γ-globulin antibodies against sheep cells were neither suited for demonstration of RF nor did they fix complement. Sheep cells coated with 7S γ-globulin antibodies of a Gm(a+) person were agglutinated by a non-rheumatoid anti-Gm(a) serum, and this system was well suited for Gm(a) typing, whereas cells coated with antibodies of a Gm(a-) person were not agglutinated. Rheumatoid anti-Gm(a) sera agglutinated cells sensitized with antibodies of both Gm(a+) and Gm(a-) persons. Using cells coated with Gm(a+) antibodies, some distinction between Gm(a+) and Gm(a-) sera could be obtained under carefully controlled conditions. The use of a Gm(a-) coat resulted in a slight difference in the inhibiting capacity, which had no relation to the serum's Gm(a) type. The results suggest that the reaction of the RF with sheep cells heavily sensitized

Red Blood Cell Agglutination for Blood Typing Within Passive Microfluidic Biochips.

PubMed

Huet, Maxime; Cubizolles, Myriam; Buhot, Arnaud

2018-04-19

Pre-transfusion bedside compatibility test is mandatory to check that the donor and the recipient present compatible groups before any transfusion is performed. Although blood typing devices are present on the market, they still suffer from various drawbacks, like results that are based on naked-eye observation or difficulties in blood handling and process automation. In this study, we addressed the development of a red blood cells (RBC) agglutination assay for point-of-care blood typing. An injection molded microfluidic chip that is designed to enhance capillary flow contained anti-A or anti-B dried reagents inside its microchannel. The only blood handling step in the assay protocol consisted in the deposit of a blood drop at the tip of the biochip, and imaging was then achieved. The embedded reagents were able to trigger RBC agglutination in situ, allowing for us to monitor in real time the whole process. An image processing algorithm was developed on diluted bloods to compute real-time agglutination indicator and was further validated on undiluted blood. Through this proof of concept, we achieved efficient, automated, real time, and quantitative measurement of agglutination inside a passive biochip for blood typing which could be further generalized to blood biomarker detection and quantification.

Mutant botrocetin-2 inhibits von Willebrand factor-induced platelet agglutination.

PubMed

Matsui, T; Hori, A; Hamako, J; Matsushita, F; Ozeki, Y; Sakurai, Y; Hayakawa, M; Matsumoto, M; Fujimura, Y

2017-03-01

Essentials Botrocetin-2 (Bot2) binds to von Willebrand factor (VWF) and induces platelet agglutination. We identified Bot2 residues that are required for binding to VWF and glycoprotein (GP) Ib. We produced a mutant Bot2 that binds to VWF but inhibits platelet agglutination. Mutant Bot2 could be used as a potential anti-thrombotic reagent to block VWF-GPIb interaction. Background Botrocetin-2 (Bot2) is a botrocetin-like protein composed of α and β subunits that have been cloned from the snake Bothrops jararaca. Bot2 binds specifically to von Willebrand factor (VWF), and the complex induces glycoprotein (GP) Ib-dependent platelet agglutination. Objectives To exploit Bot2's VWF-binding capacity in order to attempt to create a mutant Bot2 that binds to VWF but inhibits platelet agglutination. Methods and Results Several point mutations were introduced into Bot2 cDNA, and the recombinant protein (recombinant Bot2 [rBot2]) was purified on an anti-botrocetin column. The mutant rBot2 with either Ala at Asp70 in the β subunit (Aspβ70Ala), or Argβ115Ala and Lysβ117Ala, showed reduced platelet agglutination-inducing activity. rBot2 with Aspβ70Ala showed little binding activity towards immobilized VWF on an ELISA plate, whereas rBot2 with Argβ115Ala/Lysβ117Ala showed reduced binding activity towards GPIb (glycocalicin) after forming a complex with VWF. rBot2 point-mutated to oppositely charged Glu at both Argβ115 and Lysβ117 showed normal binding activity towards VWF but no platelet-agglutinating activity. Furthermore, this doubly mutated protein inhibited ristocetin-induced or high shear stress-induced platelet aggregation, and restrained thrombus formation under flow conditions. Conclusions Asp70 in the β subunit of botrocetin is important for VWF binding, and Arg115 and Lys117 in the β subunit are essential for interaction with GPIb. Doubly mutated rBot2, with Argβ115Glu and Lysβ117Glu, repels GPIb and might have potential as an antithrombotic reagent that

Sm10.3, a Member of the Micro-Exon Gene 4 (MEG-4) Family, Induces Erythrocyte Agglutination In Vitro and Partially Protects Vaccinated Mice against Schistosoma mansoni Infection

PubMed Central

Martins, Vicente P.; Morais, Suellen B.; Pinheiro, Carina S.; Assis, Natan R. G.; Figueiredo, Barbara C. P.; Ricci, Natasha D.; Alves-Silva, Juliana; Caliari, Marcelo V.; Oliveira, Sergio C.

2014-01-01

Background The parasitic flatworm Schistosoma mansoni is a blood fluke that causes schistosomiasis. Current schistosomiasis control strategies are mainly based on chemotherapy, but many researchers believe that the best long-term strategy to control disease is a combination of drug treatment and immunization with an anti-schistosome vaccine. Numerous antigens that are expressed at the interface between the parasite and the mammalian host have been assessed. Among the most promising molecules are the proteins present in the tegument and digestive tract of the parasite. Methodology/Principal Findings In this study, we evaluated the potential of Sm10.3, a member of the micro-exon gene 4 (MEG-4) family, for use as part of a recombinant vaccine. We confirmed by real-time PCR that Sm10.3 was expressed at all stages of the parasite life cycle. The localization of Sm10.3 on the surface and lumen of the esophageal and intestinal tract in adult worms and lung-stage schistosomula was confirmed by confocal microscopy. We also show preliminary evidence that rSm10.3 induces erythrocyte agglutination in vitro. Immunization of mice with rSm10.3 induced a mixed Th1/Th2-type response, as IFN-γ, TNF-α, and low levels of IL-5 were detected in the supernatant of cultured splenocytes. The protective effect conferred by vaccination with rSm10.3 was demonstrated by 25.5–32% reduction in the worm burden, 32.9–43.6% reduction in the number of eggs per gram of hepatic tissue, a 23.8% reduction in the number of granulomas, an 11.8% reduction in the area of the granulomas and a 39.8% reduction in granuloma fibrosis. Conclusions/Significance Our data suggest that Sm10.3 is a potential candidate for use in developing a multi-antigen vaccine to control schistosomiasis and provide the first evidence for a possible role for Sm10.3 in the blood feeding process. PMID:24651069

Sm10.3, a member of the micro-exon gene 4 (MEG-4) family, induces erythrocyte agglutination in vitro and partially protects vaccinated mice against Schistosoma mansoni infection.

PubMed

Martins, Vicente P; Morais, Suellen B; Pinheiro, Carina S; Assis, Natan R G; Figueiredo, Barbara C P; Ricci, Natasha D; Alves-Silva, Juliana; Caliari, Marcelo V; Oliveira, Sergio C

2014-03-01

The parasitic flatworm Schistosoma mansoni is a blood fluke that causes schistosomiasis. Current schistosomiasis control strategies are mainly based on chemotherapy, but many researchers believe that the best long-term strategy to control disease is a combination of drug treatment and immunization with an anti-schistosome vaccine. Numerous antigens that are expressed at the interface between the parasite and the mammalian host have been assessed. Among the most promising molecules are the proteins present in the tegument and digestive tract of the parasite. In this study, we evaluated the potential of Sm10.3, a member of the micro-exon gene 4 (MEG-4) family, for use as part of a recombinant vaccine. We confirmed by real-time PCR that Sm10.3 was expressed at all stages of the parasite life cycle. The localization of Sm10.3 on the surface and lumen of the esophageal and intestinal tract in adult worms and lung-stage schistosomula was confirmed by confocal microscopy. We also show preliminary evidence that rSm10.3 induces erythrocyte agglutination in vitro. Immunization of mice with rSm10.3 induced a mixed Th1/Th2-type response, as IFN-γ, TNF-α, and low levels of IL-5 were detected in the supernatant of cultured splenocytes. The protective effect conferred by vaccination with rSm10.3 was demonstrated by 25.5-32% reduction in the worm burden, 32.9-43.6% reduction in the number of eggs per gram of hepatic tissue, a 23.8% reduction in the number of granulomas, an 11.8% reduction in the area of the granulomas and a 39.8% reduction in granuloma fibrosis. Our data suggest that Sm10.3 is a potential candidate for use in developing a multi-antigen vaccine to control schistosomiasis and provide the first evidence for a possible role for Sm10.3 in the blood feeding process.

Agglutination by anti-capsular polysaccharide antibody is associated with protection against experimental human pneumococcal carriage

PubMed Central

Reiné, J; Zangari, T; Owugha, JT; Pennington, SH; Gritzfeld, JF; Wright, AD; Collins, AM; van Selm, S; de Jonge, MI; Gordon, SB; Weiser, JN; Ferreira, DM

2016-01-01

The ability of pneumococcal conjugate vaccine (PCV) to decrease transmission by blocking the acquisition of colonization has been attributed to herd immunity. We describe the role of mucosal IgG to capsular polysaccharide (CPS) in mediating protection from carriage, translating our findings from a murine model to humans. We used a flow-cytometric assay to quantify antibody-mediated agglutination demonstrating that hyperimmune sera generated against an unencapsulated mutant was poorly agglutinating. Passive immunization with this antiserum was ineffective to block acquisition of colonization compared to agglutinating antisera raised against the encapsulated parent strain. In the human challenge model samples were collected from PCV and control vaccinated adults. In PCV-vaccinated subjects IgG levels to CPS were increased in serum and nasal wash (NW). IgG to the inoculated strain CPS dropped in NW samples after inoculation suggesting its sequestration by colonizing pneumococci. In post-vaccination NW samples pneumococci were heavily agglutinated compared to pre-vaccination samples in subjects protected against carriage. Our results indicate that pneumococcal agglutination mediated by CPS specific antibodies is a key mechanism of protection against acquisition of carriage. Capsule may be the only vaccine target that can elicit strong agglutinating antibody responses, leading to protection against carriage acquisition and generation of herd immunity. PMID:27579859

Spiral computed tomography evaluation of rabbit VX2 hepatic tumors treated with 20 kHz ultrasound and microbubbles

PubMed Central

Shen, Zhi-Yong; Liu, Chun; Wu, Ming-Feng; Shi, Hai-Feng; Zhou, Yu-Feng; Zhuang, Wei; Xia, Gan-Lin

2017-01-01

The aim of the present study was to explore the therapeutic effect of 20 kHz ultrasound (US) and microbubbles (MBs) on rabbit VX2 liver tumors by spiral computed tomography (CT) scanning. A total of 16 New Zealand rabbits with hepatic VX2 tumors were divided into four groups: Control, MB, low-frequency US and US + MB. The treatment effect was evaluated by spiral CT scanning prior to, during and following treatment (at 0 weeks and the end of 1 and 2 weeks). The tumor growth rate was recorded. The specimens of VX2 tumors were collected for histological examination and transmission electron microscopy (TEM). No significant differences were observed between tumor areas measured by CT and pathology after 2-week treatment (P>0.05). The mean tumor growth rates in the control, MB, US and US + MB groups after 2 weeks of treatment were 385±21, 353±12, 302±14 and 154±9%, respectively (P<0.05, US + MB vs. the other three groups). Hematoxylin and eosin staining in the US + MB group revealed coagulation necrosis, interstitial hemorrhage and intravascular thrombosis. In the control, MB and US groups, tumor cells exhibited clear nuclear hyperchromatism. TEM of US + MB revealed vascular endothelial cell wall rupture, widened endothelial cell gaps, interstitial erythrocyte leakage and microvascular thrombosis, while intact vascular endothelial cells and normal erythrocytes in the tumor vessels were observed in the control, MB and US groups. A combination of 20 kHz US and MBs may effectively inhibit rabbit VX2 tumors. Spiral CT scanning is an ideal method to evaluate the US treatment on rabbit tumors. PMID:28928850

Taurine flux in chicken erythrocytes.

PubMed

Porter, D W; Martin, W G

1992-05-01

1. The intracellular taurine concentration in chick erythrocytes increased with age. 2. Erythrocyte taurine influx and efflux rates increased with age. 3. Erythrocyte taurine influx decreased when the extracellular sodium concentration was below normal physiological concentrations. 4. Under hypo-osmotic conditions, taurine efflux from erythrocytes increased. 5. The data suggest that chick erythrocyte taurine metabolism changes during early post-hatch development and that one taurine function may be as an osmoregulator.

Purification and characterization of a lectin from the white shrimp Litopenaeus setiferus (Crustacea decapoda) hemolymph.

PubMed

Alpuche, Juan; Pereyra, Ali; Agundis, Concepción; Rosas, Carlos; Pascual, Cristina; Slomianny, Marie-Christine; Vázquez, Lorena; Zenteno, Edgar

2005-06-20

A 291-kDa lectin (LsL) was purified from the hemolymph of the white shrimp Litopenaeus setiferus by affinity chromatography on glutaraldehyde-fixed stroma from rabbit erythrocytes. LsL is a heterotetramer of two 80-kDa and two 52-kDa subunits, with no covalently-liked carbohydrate, and mainly composed by aspartic and glutamic acids, glycine and alanine, with relatively lower methionine and cysteine contents. Edman degradation indicated that the NH2-terminal of the 80-kDa subunit is composed DASNAQKQHDVNFLL, whereas the NH2-terminal of the 52-kDa subunit is blocked. The peptide mass fingerprint of LsL was predicted from tryptic peptides from each subunit by MALDI-TOF, and revealed that each subunit showed 23 and 22%, respectively, homology with the hemocyanin precursor from Litopenaeus vannamei. Circular dichroism analysis revealed beta sheet and alpha helix contents of 52.7 and 6.1%, respectively. LsL agglutinate at higher titers guinea pig, murine, and rabbit erythrocytes its activity is divalent cation-dependent. N-acetylated sugars, such as GlcNAc, GalNAc, and NeuAc, were the most effective inhibitors of the LsL hemagglutinating activity. Sialylated O-glycosylated proteins, such as bovine submaxillary gland mucin, human IgA, and fetuin, showed stronger inhibitory activity than sialylated N-glycosylated proteins, such as human orosomucoid, IgG, transferrin, and lactoferrin. Desialylation of erythrocytes or inhibitory glycoproteins abolished their capacity to bind LsL, confirming the relevance of sialic acid in LsL-ligand interactions.

Soybean extracts facilitate bacterial agglutination and prevent biofilm formation on orthodontic wire.

PubMed

Lee, Heon-Jin; Kwon, Tae-Yub; Kim, Kyo-Han; Hong, Su-Hyung

2014-01-01

Soybean is an essential food ingredient that contains a class of organic compounds known as isoflavones. It is also well known that several plant agglutinins interfere with bacterial adherence to smooth surfaces. However, little is known about the effects of soybean extracts or genistein (a purified isoflavone from soybean) on bacterial biofilm formation. We evaluated the effects of soybean (Glycine max) extracts, including fermented soybean and genistein, on streptococcal agglutination and attachment onto stainless steel orthodontic wire. After cultivating streptococci in biofilm medium containing soybean extracts and orthodontic wire, the viable bacteria attached to the wire were counted. Phase-contrast microscopy and scanning electron microscopy (SEM) analyses were conducted to evaluate bacterial agglutination and attachment. Our study showed that soybean extracts induce agglutination between streptococci, which results in bacterial precipitation. Conversely, viable bacterial counting and SEM image analysis of Streptococcus mutans attached to the orthodontic wire show that bacterial attachment decreases significantly when soybean extracts were added. However, there was no significant change in pre-attached S. mutans biofilm in response to soybean. A possible explanation for these results is that increased agglutination of planktonic streptococci by soybean extracts results in inhibition of bacterial attachment onto the orthodontic wire.

Prevalence of antinuclear and anti-erythrocyte antibodies in healthy cats.

PubMed

Abrams-Ogg, Anthony C G; Lim, Sophia; Kocmarek, Helen; Ho, Kim; Blois, Shauna L; Shewen, Patricia E; Wood, R Darren; Bienzle, Dorothee

2018-03-01

Positive antinuclear antibody and direct antiglobulin tests support diagnoses such as systemic lupus erythematosus and immune-mediated anemia, respectively. Positive tests may occur in cats, but the prevalence of positive results in healthy cats is not well known. The study's purpose was to determine prevalences of positive antinuclear antibody and direct antiglobulin tests in healthy cats. Antinuclear antibody titers were measured by indirect immunofluorescence, and anti-erythrocyte antibodies were measured by the microtitration direct antiglobulin test at 37, 23, and 4°C in 61 client-owned and 28 facility-owned cats. Differences between the 2 groups were examined using chi-squared tests. For the antinuclear antibody tests, 70% of client-owned cats were negative, 10% had weak titers (1:40-1:80), and 20% had strong titers (1:160-1:320). Facility-owned cats had significantly fewer positive titers with 96% negative and one positive (1:8). For the antiglobulin test at 37°C, 93% of all cats were negative, 2 cats in each group were positive at low dilutions (1:2), and 2 client-owned cats were transiently positive at high dilutions (≥ 1:2048). At 23°C, 90% of all cats were negative, and 2 client-owned and 5 facility-owned cats were positive at low dilutions (1:2-1:8). At 4°C, 67% of client-owned cats had invalid results (negative control well agglutination), and 33% had negative results, while of facility-owned cats 14% had invalid results, 14% had agglutination at low dilutions, and 72% were negative. Healthy cats may have positive antinuclear antibody and direct antiglobulin tests, but the prevalence of strong reactions is low. © 2018 American Society for Veterinary Clinical Pathology.

Klebsiella pneumoniae type 3 fimbriae agglutinate yeast in a mannose-resistant manner.

PubMed

Stahlhut, Steen G; Struve, Carsten; Krogfelt, Karen A

2012-03-01

The ability of bacterial pathogens to express different fimbrial adhesins plays a significant role in virulence. Thus, specific detection of fimbrial expression is an important task in virulence characterization and epidemiological studies. Most clinical Klebsiella pneumoniae isolates express type 1 and type 3 fimbriae, which are characterized by mediation of mannose-sensitive agglutination of yeast cells and agglutination of tannic acid-treated ox red blood cells (RBCs), respectively. It has been observed that K. pneumoniae isolates agglutinate yeast cells and commercially available sheep RBCs in a mannose-resistant manner. Thus, this study was initiated to identify the adhesin involved. Screening of a mutant library surprisingly revealed that the mannose-resistant agglutination of yeast and sheep RBCs was mediated by type 3 fimbriae. Specific detection of type 1 fimbriae expression in K. pneumoniae was feasible only by the use of guinea pig RBCs. This was further verified by the use of isogenic fimbriae mutants and by cloning and expressing K. pneumoniae fimbrial gene clusters in Escherichia coli. Yeast agglutination assays are commonly used to detect type 1 fimbriae expression but should not be used for bacterial species able to express type 3 fimbriae. For these species, the use of guinea pig blood for specific type 1 fimbriae detection is essential. The use of commercially available sheep RBCs or yeast is an easy alternative to traditional methods to detect type 3 fimbriae expression. Easy and specific detection of expression of type 1 and type 3 fimbriae is essential in the continuous characterization of these important adhesive virulence factors present in members of the Enterobacteriaceae.

Are the Major Agglutinative Languages Genetically Related?

ERIC Educational Resources Information Center

Hakola, H. P. A.

1989-01-01

Examination of accidental CVC and CV correspondences among languages representing 5 large families of agglutinative languages found that comparison pairs had much more similarity between basic 100-word vocabularies than would have been possible by mere chance, supporting the hypothesis that those 5 language families were mutually related.…

[Influence of S-nitrosoglutathione on agglutination and nitric oxide concentration in frozen platelets].

PubMed

Wu, Tao; Liu, Jing-Han; Li, Hui; Zhou, Wu; Wang, Shu-Ying

2012-04-01

The aim of this study was to investigate the influence of S-nitrosoglutathione (GSNO) on agglutination and nitric oxide (NO) concentration in frozen platelets. The agglutination of platelets was detected by using platelet agglutination apparatus, the level of NO in platelets was detected by the nitrate enzyme reduction method. The results showed that the rates of agglutination in freeze platelets and frozen platelets treated with GSNO were (35.47 ± 2.93) and (24.43 ± 3.07), which were significantly lower than that in fresh liquid platelets (63.44 ± 2.96). The level of NO concentration in frozen platelets was (22.16 ± 6.38), which was significantly lower than that in fresh liquid platelets (31.59 ± 16.88). The level of NO concentration in frozen platelets treated with GSNO was (45.64 ± 6.31), which was significantly higher than that in fresh liquid platelets (P < 0.01). It is concluded that GSNO increases the concentration of NO in frozen platelets, inhibits platelet activation and maintains platelet function, thus GSNO can be used as a frozen protective agent.

Comparative evaluation of recombinant LigB protein and heat-killed antigen-based latex agglutination test with microscopic agglutination test for diagnosis of bovine leptospirosis.

PubMed

Nagalingam, Mohandoss; Thirumalesh, Sushma Rahim Assadi; Kalleshamurthy, Triveni; Niharika, Nakkala; Balamurugan, Vinayagamurthy; Shome, Rajeswari; Sengupta, Pinaki Prasad; Shome, Bibek Ranjan; Prabhudas, Krishnamsetty; Rahman, Habibur

2015-10-01

This study aimed to develop latex agglutination test (LAT) using recombinant leptospiral immunoglobulin-like protein (LigB) (rLigB) antigen and compare its diagnostic efficacy with LAT using conventional heat-killed leptospiral antigen and microscopic agglutination test (MAT) in diagnosing bovine leptospirosis. The PCR-amplified 1053-bp ligB gene sequences from Leptospira borgpetersenii Hardjo serovar were cloned in pET 32 (a) vector at EcoRI and NotI sites and expressed in BL21 E. coli cells as fusion protein with thioredoxin (-57 kDa) and characterized by SDS-PAGE and immunoblot. Out of 390 serum samples [cattle (n = 214), buffaloes (n = 176)] subjected to MAT, 115 samples showed reciprocal titre≥100 up to 1600 against one or more serovars. For recombinant LigB protein/antigen-based LAT, agglutination was observed in the positive sample, while no agglutination was observed in the negative sample. Similarly, heat-killed leptospiral antigen was prepared from and used in LAT for comparison with MAT. A two-sided contingency table was used for analysis of LAT using both the antigens separately against MAT for 390 serum samples. The sensitivity, specificity and positive and negative predictive values of recombinant LigB LAT were found to be 75.65, 91.27, 78.38 and 89.96 %, respectively, and that of heat-killed antigen-based LAT were 72.17, 89.82, 74.77 and 88.53 %, respectively, in comparison with MAT. This developed test will be an alternative/complementary to the existing battery of diagnostic assays/tests for specific detection of pathogenic Leptospira infection in bovine population.

Simplified spectraphotometric method for the detection of red blood cell agglutination.

PubMed

Ramasubramanian, Melur; Anthony, Steven; Lambert, Jeremy

2008-08-01

Human error is the most significant factor attributed to incompatible blood transfusions. A spectrophotometric approach to blood typing has been developed by examining the spectral slopes of dilute red blood cell (RBC) suspensions in saline, in the presence and absence of various antibodies, offering a technique for the quantitative determination of agglutination intensity [Transfusion39, 1051, 1999TRANAT0041-113210.1046/j.1537-2995.1999.39101051.x]. We offer direct theoretical prediction of the observed change in slope in the 660-1000 nm range through the use of the T-matrix approach and Lorenz-Mie theory for light scattering by dilute RBC suspensions. Following a numerical simulation using the T-matrix code, we present a simplified sensing method for detecting agglutination. The sensor design has been prototyped, fully characterized, and evaluated through a complete set of tests with over 60 RBC samples and compared with the full spectrophotometric method. The LED and photodiode pairs are found to successfully reproduce the spectroscopic determination of red blood cell agglutination.

Single agglutinates: A comparative study of compositions of agglutinitic glass, whole-grain, bulk soil, and FMR

NASA Technical Reports Server (NTRS)

Basu, A.; Robinson, R.; Mckay, D. S.; Blanchard, D. P.; Morris, R. V.; Wentworth, Susan J.

1994-01-01

Previous workers on single agglutinates have variously interpreted the composition of agglutinitic glass to represent impact melts of (1) bulk soil, (2) mixed components in finer sizes, and (3) microtargets. Separately, Papike has argued in favor of fusion of the finest fraction of bulk soils. Thirty-four single agglutinates were hand-picked from the mature Apollo 16 soil 61181 (I(sub s)/FeO = 82) and the FMR and chemical composition (INAA for Fe, Sc, Sm, Co, Ni, and Cr) of each agglutinate particle were measured. Thirteen of these single agglutinates were selected for electron beam microanalysis and imaging. Less than 1 micron spots were analyzed (for Na, Mg, Al, Si, P, S, K, Ca, Ti, Cr, Mn, Fe, Ni, and Ba) on pure glassy areas (approximately ten in each particle) selected on the basis of optical and BSE images (avoiding all clasts and inclusions) with an electron microprobe to obtain average glass compositions of each single agglutinate.

Process to create simulated lunar agglutinate particles

NASA Technical Reports Server (NTRS)

Gustafson, Robert J. (Inventor); Gustafson, Marty A. (Inventor); White, Brant C. (Inventor)

2011-01-01

A method of creating simulated agglutinate particles by applying a heat source sufficient to partially melt a raw material is provided. The raw material is preferably any lunar soil simulant, crushed mineral, mixture of crushed minerals, or similar material, and the heat source creates localized heating of the raw material.

Experimental shock metamorphism of terrestrial basalts: Agglutinate-like particle formation, petrology, and magnetism

NASA Astrophysics Data System (ADS)

Badyukov, Dmitrii D.; Bezaeva, Natalia S.; Rochette, Pierre; Gattacceca, Jérôme; Feinberg, Joshua M.; Kars, Myriam; Egli, Ramon; Raitala, Jouko; Kuzina, Dilyara M.

2018-01-01

Hypervelocity impacts occur on bodies throughout our solar system, and play an important role in altering the mineralogy, texture, and magnetic properties in target rocks at nanometer to planetary scales. Here we present the results of hypervelocity impact experiments conducted using a two-stage light-gas gun with 5 mm spherical copper projectiles accelerated toward basalt targets with 6 km s-1 impact velocities. Four different types of magnetite- and titanomagnetite-bearing basalts were used as targets for seven independent experiments. These laboratory impacts resulted in the formation of agglutinate-like particles similar in texture to lunar agglutinates, which are an important fraction of lunar soil. Materials recovered from the impacts were examined using a suite of complementary techniques, including optical and scanning electron microscopy, micro-Raman spectroscopy, and high- and low-temperature magnetometry, to investigate the texture, chemistry, and magnetic properties of newly formed agglutinate-like particles and were compared to unshocked basaltic parent materials. The use of Cu-projectiles, rather than Fe- and Ni-projectiles, avoids magnetic contamination in the final shock products and enables a clearer view of the magnetic properties of impact-generated agglutinates. Agglutinate-like particles show shock features, such as melting and planar deformation features, and demonstrate shock-induced magnetic hardening (two- to seven-fold increases in the coercivity of remanence Bcr compared to the initial target materials) and decreases in low-field magnetic susceptibility and saturation magnetization.

Disorders of erythrocyte hydration.

PubMed

Gallagher, Patrick G

2017-12-21

The erythrocyte contains a network of pathways that regulate salt and water content in the face of extracellular and intracellular osmotic perturbations. This allows the erythrocyte to maintain a narrow range of cell hemoglobin concentration, a process critical for normal red blood cell function and survival. Primary disorders that perturb volume homeostasis jeopardize the erythrocyte and may lead to its premature destruction. These disorders are marked by clinical, laboratory, and physiologic heterogeneity. Recent studies have revealed that these disorders are also marked by genetic heterogeneity. They have implicated roles for several proteins, PIEZO1, a mammalian mechanosensory protein; GLUT1, the glucose transporter; SLC4A1, the anion transporter; RhAG, the Rh-associated glycoprotein; KCNN4, the Gardos channel; and ABCB6, an adenosine triphosphate-binding cassette family member, in the maintenance of erythrocyte volume homeostasis. Secondary disorders of erythrocyte hydration include sickle cell disease, thalassemia, hemoglobin CC, and hereditary spherocytosis, where cellular dehydration may be a significant contributor to disease pathology and clinical complications. Understanding the pathways regulating erythrocyte water and solute content may reveal innovative strategies to maintain normal volume in disorders associated with primary or secondary cellular dehydration. These mechanisms will serve as a paradigm for other cells and may reveal new therapeutic targets for disease prevention and treatment beyond the erythrocyte. © 2017 by The American Society of Hematology.

Dodecamer is required for agglutination of Litopenaeus vannamei hemocyanin with bacterial cells and red blood cells.

PubMed

Pan, Jian-yi; Zhang, Yue-ling; Wang, San-ying; Peng, Xuan-xian

2008-01-01

Hemocyanins are multi-functional proteins, although they are well known to be respiratory proteins of invertebrate to date. In the present study, the agglutination ability of two oligomers of hemocyanin, hexamer and dodecamer, with pathogenic bacteria and red blood cells (RBCs) is investigated in pacific white shrimp, Litopenaeus vannamei. Hexameric hemocyanin exhibits an extremely high stability even in the absence of Ca(2+) and in alkaline pH. Dodecamer (di-hexamer) is easily dissociated into hexamers in unphysiological conditions. Hexamer and dodecamer are interchanged reciprocally with environmental conditions. Both oligomers can bind to bacteria and RBCs, but agglutination is observed only using dodecamer but not using hexamer in agglutination assay. However, the agglutination is detected when hexamer is utilized in the presence of antiserum against hemocyanin. These results indicate that dodecamer of hemocyanin is required for agglutination with bacteria and RBCs. It can be logically inferred that there is only one carbohydrate-binding site to bacterial cells and RBCs in the hexamer, while at least two sites in the dodecamer. Our finding has provided new insights into structural-functional relationship of hemocyanin.

Mapping of hemoglobin in erythrocytes and erythrocyte ghosts using two photon excitation fluorescence microscopy

NASA Astrophysics Data System (ADS)

Bukara, Katarina; Jovanić, Svetlana; Drvenica, Ivana T.; Stančić, Ana; Ilić, Vesna; Rabasović, Mihailo D.; Pantelić, Dejan; Jelenković, Branislav; Bugarski, Branko; Krmpot, Aleksandar J.

2017-02-01

The present study describes utilization of two photon excitation fluorescence (2PE) microscopy for visualization of the hemoglobin in human and porcine erythrocytes and their empty membranes (i.e., ghosts). High-quality, label- and fixation-free visualization of hemoglobin was achieved at excitation wavelength 730 nm by detecting visible autofluorescence. Localization in the suspension and spatial distribution (i.e., mapping) of residual hemoglobin in erythrocyte ghosts has been resolved by 2PE. Prior to the 2PE mapping, the presence of residual hemoglobin in the bulk suspension of erythrocyte ghosts was confirmed by cyanmethemoglobin assay. 2PE analysis revealed that the distribution of hemoglobin in intact erythrocytes follows the cells' shape. Two types of erythrocytes, human and porcine, characterized with discocyte and echinocyte morphology, respectively, showed significant differences in hemoglobin distribution. The 2PE images have revealed that despite an extensive washing out procedure after gradual hypotonic hemolysis, a certain amount of hemoglobin localized on the intracellular side always remains bound to the membrane and cannot be eliminated. The obtained results open the possibility to use 2PE microscopy to examine hemoglobin distribution in erythrocytes and estimate the purity level of erythrocyte ghosts in biotechnological processes.

Effect of salivary agglutination on oral streptococcal clearance by human polymorphonuclear neutrophil granulocytes

PubMed Central

Itzek, Andreas; Chen, Zhiyun; Merritt, Justin; Kreth, Jens

2016-01-01

Salivary agglutination is an important host defense mechanism to aggregate oral commensal bacteria as well as invading pathogens. Saliva flow and subsequent swallowing more easily clear aggregated bacteria compared to single cells. Phagocytic clearance of bacteria through polymorphonuclear neutrophil granulocytes also seems to increase to a certain extent with the size of bacterial aggregates. To determine a connection between salivary agglutination and the host innate immune response by phagocytosis, an in vitro agglutination assay was developed reproducing the average size of salivary bacterial aggregates. Using the oral commensal Streptococcus gordonii as a model organism, the effect of salivary agglutination to the phagocytic clearance through polymorphonuclear neutrophil granulocytes was investigated. Here we describe that salivary aggregates of S. gordonii are readily cleared through phagocytosis, while single bacterial cells showed a significant delay in being phagocytosed and killed. Furthermore, prior to phagocytosis the polymorphonuclear neutrophil granulocytes were able to induce a specific de-aggregation, which was dependent on serine protease activity. The herein presented data suggest that salivary agglutination of bacterial cells leads to an ideal size for recognition by polymorphonuclear neutrophil granulocytes. As a first line of defense, these phagocytic cells are able to recognize the aggregates and de-aggregate them via serine proteases to a more manageable size for efficient phagocytosis and subsequent killing in the phagolysosome. This observed mechanism not only prevents the rapid spreading of oral bacterial cells while entering the bloodstream but would also avoid degranulation of involved polymorphonuclear neutrophil granulocytes thus preventing collateral damage to nearby tissue. PMID:27194631

Effect of salivary agglutination on oral streptococcal clearance by human polymorphonuclear neutrophil granulocytes.

PubMed

Itzek, A; Chen, Z; Merritt, J; Kreth, J

2017-06-01

Salivary agglutination is an important host defense mechanism to aggregate oral commensal bacteria as well as invading pathogens. Saliva flow and subsequent swallowing more easily clear aggregated bacteria compared with single cells. Phagocytic clearance of bacteria through polymorphonuclear neutrophil granulocytes also seems to increase to a certain extent with the size of bacterial aggregates. To determine a connection between salivary agglutination and the host innate immune response by phagocytosis, an in vitro agglutination assay was developed reproducing the average size of salivary bacterial aggregates. Using the oral commensal Streptococcus gordonii as a model organism, the effect of salivary agglutination on phagocytic clearance through polymorphonuclear neutrophil granulocytes was investigated. Here we describe how salivary aggregates of S. gordonii are readily cleared through phagocytosis, whereas single bacterial cells showed a significant delay in being phagocytosed and killed. Furthermore, before phagocytosis the polymorphonuclear neutrophil granulocytes were able to induce a specific de-aggregation, which was dependent on serine protease activity. The data presented suggest that salivary agglutination of bacterial cells leads to an ideal size for recognition by polymorphonuclear neutrophil granulocytes. As a first line of defense, these phagocytic cells are able to recognize the aggregates and de-aggregate them via serine proteases to a more manageable size for efficient phagocytosis and subsequent killing in the phagolysosome. This observed mechanism not only prevents the rapid spreading of oral bacterial cells while entering the bloodstream but would also avoid degranulation of involved polymorphonuclear neutrophil granulocytes, so preventing collateral damage to nearby tissue. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Conventional Rapid Latex Agglutination in Estimation of von Willebrand Factor: Method Revisited and Potential Clinical Applications

PubMed Central

Che Hussin, Che Maraina

2014-01-01

Measurement of von Willebrand factor antigen (VWF : Ag) levels is usually performed in a specialised laboratory which limits its application in routine clinical practice. So far, no commercial rapid test kit is available for VWF : Ag estimation. This paper discusses the technical aspect of latex agglutination method which was established to suit the purpose of estimating von Willebrand factor (VWF) levels in the plasma sample. The latex agglutination test can be performed qualitatively and semiquantitatively. Reproducibility, stability, linearity, limit of detection, interference, and method comparison studies were conducted to evaluate the performance of this test. Semiquantitative latex agglutination test was strongly correlated with the reference immunoturbidimetric assay (Spearman's rho = 0.946, P < 0.001, n = 132). A substantial agreement (κ = 0.77) was found between qualitative latex agglutination test and the reference assay. Using the scoring system for the rapid latex test, no agglutination is with 0% VWF : Ag (control negative), 1+ reaction is equivalent to <20% VWF : Ag, and 4+ reaction indicates >150% VWF : Ag (when comparing with immunoturbidimetric assay). The findings from evaluation studies suggest that latex agglutination method is suitable to be used as a rapid test kit for the estimation of VWF : Ag levels in various clinical conditions associated with high levels and low levels of VWF : Ag. PMID:25759835

A method for measuring different classes of human immunoglobulins specific for the penicilloyl group

PubMed Central

Wheeler, A. W.

1971-01-01

A method is described for the detection of human immunoglobulins of the four main classes specific for the penicilloyl group. The technique is an adaptation of the red cell linked antigen antiglobulin reaction based on the finding that benzyl penicilloylated rabbit γ-globulin, specific for human erythrocytes, reacted specifically with erythrocytes but did not agglutinate them. In turn this complex reacted specifically with human penicilloyl antibody and it was then possible to titrate each immunoglobulin class by the addition of anti-immunoglobulin sera. The method described here was used to compare titres of penicilloyl specific immunoglobulins of the same class between different sera. The test was found to be less sensitive than the hapten modified bacteriophage reduction test but had the advantage that individual immunoglobulin classes could be compared. In the absence of a reliable method for the diagnosis of pencillin allergy, it is hoped that the technique described will be a useful addition to existing in vivo and in vitro methods of determining the antibody response of the patient to the penicilloyl group. PMID:4105475

The incomplete anti-Rh antibody agglutination mechanism of trypsinized ORh+ red cells.

PubMed Central

Margni, R A; Leoni, J; Bazzurro, M

1977-01-01

The capacity for binding to trypsinized and non-trypsinized ORh+ red cells, of the IgG incomplete anti-Rh antibody and its F(ab')2 and Fc fragments has been investigated. An analysis has also been made of the capacity of non-specific human IgG, aggregated non-specific human IgG, human IgM (19S) and IgM (7S), and of fragments Fcgamma, Fcmu and Fc5mu to inhibit the agglutination of trypsinized ORh+ red cells by the IgG incomplete anti-Rh antibody. The results obtained indicate that these antibodies behave in a similar manner to that of nonprecipitating antibodies, and that the agglutination of trypsinized red cells seems to be a mixed reaction due to the interaction of an Fab fragment with its Rh antigenic determinant present in the surface of a red cell and the Fc of the same molecule with a receptor for Fc present in adjacent red cells. The trypsin treatment apparently results in the liberation of occult Fc receptors. It has also been demonstrated that in the agglutination of ORh+ red cells by IgG incomplete anti-Rh antibody in the presence of albumin, interaction must occur in some manner between the albumin and the Fc fragment since the F(ab')2 fragment does not give rise to agglutination under such conditions. Images Figure 1 PMID:415968

Evaluation of agglutination strength by a flow-induced cell movement assay based surface plasmon resonance (SPR) technique.

PubMed

Sudprasert, Krisda; Peungthum, Patjaree; Vongsakulyanon, Apirom; Amarit, Ratthasart; Somboonkaew, Armote; Sutapun, Boonsong; Kitpoka, Pimpun; Kunakorn, Mongkol; Srikhirin, Toemsak

2015-02-07

A flow-induced cell movement assay combined with a surface plasmon resonance (SPR) technique was developed to quantify the agglutination strength, derived from the standard tube-agglutination test. Red blood cells (RBCs), based on the ABO blood group system, were specifically captured by anti-A and/or anti-B antibodies immobilized on a sensor surface. The agglutination strength corresponds to the amount of antigen-antibody interactions or the strength of RBC adhesion. Under a shear flow, the adherent RBCs were forced to move out of the region of interest with different average cell velocities (vc) depending upon the adhesion strength and wall shear stress (WSS). That is, a higher adhesion strength (higher agglutination strength) or lower WSS represents a lower vc or vice versa. In this work, the agglutination strength was derived from the vc that was calculated from the time derivative of the relative SPR signal by using a simple model of cell movement response, whose validity was verified. The vc values of different samples were correlated with their agglutination strengths at a given WSS and antibody surface density. The vc decreased as the agglutination strength increased, which can be considered as a linear regression. The coefficient of variation of the calculated vc decreased to 0.1 as vc increased to 30 μm min(-1). The sensitivity of this assay can be controlled by optimizing the antibody surface density or the WSS. This assay has the capability to resolve the antigen density of A1 and B RBCs from that of A1B RBCs.

Erythrocyte and blood antibacterial defense

PubMed Central

2014-01-01

It is an axiom that blood cellular immunity is provided by leukocytes. As to erythrocytes, it is generally accepted that their main function is respiration. Our research provides objective video and photo evidence regarding erythrocyte bactericidal function. Phase-contrast immersion vital microscopy of the blood of patients with bacteremia was performed, and the process of bacteria entrapping and killing by erythrocytes was shot by means of video camera. Video evidence demonstrates that human erythrocytes take active part in blood bactericidal action and can repeatedly engulf and kill bacteria of different species and size. Erythrocytes are extremely important integral part of human blood cellular immunity. Compared with phagocytic leukocytes, the erythrocytes: a) are more numerous; b) are able to entrap and kill microorganisms repeatedly without being injured; c) are more resistant to infection and better withstand the attacks of pathogens; d) have longer life span and are produced faster; e) are inauspicious media for proliferation of microbes and do not support replication of chlamidiae, mycoplasmas, rickettsiae, viruses, etc.; and f) are more effective and uncompromised bacterial killers. Blood cellular immunity theory and traditional view regarding the function of erythrocytes in human blood should be revised. PMID:24883200

Clostridial toxins active locally in the gastrointestinal tract.

PubMed

Wilkins, T; Krivan, H; Stiles, B; Carman, R; Lyerly, D

1985-01-01

Clostridium difficile and Clostridium spiroforme have only in recent years been recognized as intestinal pathogens. They both produce toxins that are also produced by other clostridia. C. difficile toxins A and B are produced by C. sordellii and a few strains of C. perfringens whereas C. spiroforme produces the same toxins as C. perfringens Type E (iota toxin). Iota toxin activity may be the product of two proteins. Toxigenic strains of C. spiroforme and Type E produce two antigens which possess much more biological activity when administered together than when given alone. C. difficile was thought for some time to produce only a single toxin, but then the enterotoxic activity was shown to be due to a separate toxin (toxin A). This toxin increases the oral toxicity of toxin B (the main cytotoxin) and may increase the permeability of the colon. Toxin A binds to a specific receptor in hamster brush border membranes and in the membranes of rabbit erythrocytes. This receptor appears to be a glycoprotein. The receptor can be extracted from the membrane with Triton and binds to immobilized toxin A. The receptor can be extracted and used to coat plastic plates as a first phase in an ELISA assay. Another assay has been developed in which the toxin A binds to the red cells and then the erythrocytes are agglutinated with antitoxin. An even more sensitive assay consists of using rabbit erythrocyte ghosts to bind the toxin and then precipitating the ghosts with antibody to toxin A attached to latex beads. Monoclonal antibodies to toxin A also have been developed and are used in these and other assays.

The reactivities of human erythrocyte autoantibodies anti-Pr2, anti-Gd, Fl and Sa with gangliosides in a chromatogram binding assay.

PubMed Central

Uemura, K; Roelcke, D; Nagai, Y; Feizi, T

1984-01-01

The thin layer chromatogram binding assay was used to study the reaction of several natural-monoclonal autoantibodies which recognize sialic acid-dependent antigens of human erythrocytes. Immunostaining of gangliosides derived from human and bovine erythrocytes was achieved with four autoantibodies designated anti-Pr2, anti-Gd, Sa and Fl, each of which has a different haemagglutination pattern with untreated and proteinase-treated erythrocytes and with cells of I and i antigen types. From the chromatogram binding patterns of anti-Pr2 with gangliosides of the neolacto and the ganglio series, it is deduced that this antibody reacts best with N-acetylneuraminic acid when it is alpha 2-3- or alpha 2-6-linked to a terminal Gal(beta 1-4)Glc/GlcNAc GlcNAc sequence and to a lesser extent when it is alpha 2-3-linked to a terminal Gal(beta 1-3)GalNAc sequence or to an internal galactose and when it is alpha 2-8-linked to another, internal N-acetylneuraminic acid residue. The other three antibodies differ from anti-Pr2 in their lack of reaction with glycolipids of the ganglio series. They react with the NeuAc(alpha 2-3)Gal(beta 1-4)Glc/GlcNAc sequence as found in GM3 and in glycolipids of the neolacto series, but show a preference for the latter, longer sequences. Thus all four antibodies react with sialylated oligosaccharides containing i type (linear) and I type (branched) neolacto backbones. Fl antibody differs from the other three in its stronger reaction with branched neolacto sequences in accordance with its stronger agglutination of erythrocytes of I rather than i type. The four antibodies show a specificity for N-acetyl- rather than N-glycolyl-neuraminic acid. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. PMID:6204642

[Erythrocytic enzymopathy in Uzbekistan].

PubMed

Bakhramov, S M; Ashrabhodzhaeva, K K

2011-01-01

Erythrocyte enzymes participate in the main interactions promoting utilization of glucose-glycolytic, pentosophosphate cycles and glutation system. In this report we study on erythrocyte G6PD deficiency which is the impairment related to the gender and expressed with development of acute drug-associated hemolytic anemia. Out of 13187 studied subjects 122 showed carrying of deficiency of erythrocyte G6PD activity, from them 98 (80.3%) subjects were male, and 24 (19.7%) female. As a whole, among the revealed in the population studies, and also verified in clinic of the persons with deficiency of erythrocyte G6PD there were marked different pathological phenotypes: hereditary nonspherecytary hemolytic anemia, acute drug-induced hemolytic anemia, asymptomatic gene carrying and, selected by us disease with few symptoms. As a whole, among the revealed in the population studies, and also verified in clinic of the persons with deficiency of erythrocyte G6PD there were marked different pathological phenotypes: hereditary nonspherecytary hemolytic anemia, acute drug-induced hemolytic anemia, asymptomatic gene carrying and, selected by us disease with few symptoms.

Fetal-maternal erythrocyte distribution

MedlinePlus

... under the skin) Infection (a slight risk any time the skin is broken) Alternative Names Kleihauer-Betke stain; Flow cytometry - fetal-maternal erythrocyte distribution; Rh incompatibility - erythrocyte distribution References Chernecky CC, Berger ...

'Agglutination and flocculation' of stem cells collected by apheresis due to cryofibrinogen.

PubMed

Siegenthaler, M A; Vu, D-H; Ebnöther, M; Ketterer, N; Luthi, F; Schmid, P; Bargetzi, M; Gasparini, D; Tissot, J-D

2004-04-01

Collection of peripheral stem cells by apheresis is a well-described process. Here, investigations concerning 'agglutination and flocculation' of stem cells collected from two patients are described. In both cases, cryoproteins were observed and cryofibrinogen was identified using high-resolution two-dimensional electrophoresis. In one case, peripheral stem cells were collected after a second course of mobilization, and the cells were immediately washed at 37 degrees C before being frozen, allowing their use, despite the presence of cryofibrinogen. In the other case, 'agglutination' was reversed by warming the bag, and plasma was removed before freezing.

Interfering lipoproteins in magnetic field-assisted agglutination of superparamagnetic particles immunoassay.

PubMed

Cauet, Gilles; Daynès, Aurélien; Temurok, Nevzat

2016-04-01

The technology of magnetic field-assisted immuno-agglutination of superparamagnetic particles allows sensitive detection of biomarkers in whole blood. However, we observed non-specific agglutination (NSA), due to interfering plasma proteins, that negatively affects C-reactive protein immunoassay. The objective of the study was to identify the plasma proteins involved and to eliminate these interferences. Plasma was fractionated by size exclusion HPLC and each fraction was tested for non-specific agglutination. In addition, plasma proteins bound to magnetic particles were analyzed by SDS-gel electrophoresis and identified by mass spectrometry. We found that NSA was due to the binding of some lipoproteins to the particles. NSA was observed in the presence of purified LDL and VLDL but not HDL. NSA was mediated by the binding of ApoB100 to magnetic particles through its heparin binding sites. These interferences could be eliminated by addition of heparin or other polyanions like dextran sulfate to the assay buffer. NSA results from the binding of some plasma lipoproteins to magnetic particles. The use of a polyanion to eliminate these interferences allows the formulation of a stable reagent.

Real time observation and automated measurement of red blood cells agglutination inside a passive microfluidic biochip containing embedded reagents.

PubMed

Huet, Maxime; Cubizolles, Myriam; Buhot, Arnaud

2017-07-15

The process of agglutination is commonly used for the detection of biomarkers like proteins or viruses. The multiple bindings between micrometer sized particles, either latex beads or red blood cells (RBCs), create aggregates that are easily detectable and give qualitative information about the presence of the biomarkers. In most cases, the detection is made by simple naked-eye observation of agglutinates without any access to the kinetics of agglutination. In this study, we address the development of a real-time time observation of RBCs agglutination. Using ABO blood typing as a proof-of-concept, we developed i) an integrated biological protocol suitable for further use as point-of-care (POC) analysis and ii) two dedicated image processing algorithms for the real-time and quantitative measurement of agglutination. Anti-A or anti-B typing reagents were dried inside the microchannel of a passive microfluidic chip designed to enhance capillary flow. A blood drop deposit at the tip of the biochip established a simple biological protocol. In situ agglutination of autologous RBCs was achieved by means of embedded reagents and real time agglutination process was monitored by video recording. Using a training set of 24 experiments, two real-time indicators based on correlation and variance of gray levels were optimized and then further confirmed on a validation set. 100% correct discrimination between positive and negative agglutinations was performed within less than 2min by measuring real-time evolution of both correlation and variance indicators. Copyright © 2016 Elsevier B.V. All rights reserved.

The Production of Nominal and Verbal Inflection in an Agglutinative Language: Evidence from Hungarian

PubMed Central

Peckham, Don; Szanka, Szilvia; Gazso, Dorottya; Lovassy, Noemi; Ullman, Michael T.

2015-01-01

The contrast between regular and irregular inflectional morphology has been useful in investigating the functional and neural architecture of language. However, most studies have examined the regular/irregular distinction in non-agglutinative Indo-European languages (primarily English) with relatively simple morphology. Additionally, the majority of research has focused on verbal rather than nominal inflectional morphology. The present study attempts to address these gaps by introducing both plural and past tense production tasks in Hungarian, an agglutinative non-Indo-European language with complex morphology. Here we report results on these tasks from healthy Hungarian native-speaking adults, in whom we examine regular and irregular nominal and verbal inflection in a within-subjects design. Regular and irregular nouns and verbs were stem on frequency, word length, and phonological structure, and both accuracy and response times were acquired. The results revealed that the regular/irregular contrast yields similar patterns in Hungarian, for both nominal and verbal inflection, as in previous studies of non-agglutinative Indo-European languages: the production of irregular inflected forms was both less accurate and slower than of regular forms, both for plural and past-tense inflection. The results replicate and extend previous findings to an agglutinative language with complex morphology. Together with previous studies, the evidence suggests that the regular/irregular distinction yields a basic behavioral pattern that holds across language families and linguistic typologies. Finally, the study sets the stage for further research examining the neurocognitive substrates of regular and irregular morphology in an agglutinative non-Indo-European language. PMID:25769039

Influence of Erythrocyte Membrane Stability in Atherosclerosis.

PubMed

da Silva Garrote-Filho, Mario; Bernardino-Neto, Morun; Penha-Silva, Nilson

2017-04-01

The purpose of this study is to show how an excess of cholesterol in the erythrocyte membrane contributes stochastically to the progression of atherosclerosis, leading to damage in blood rheology and O 2 transport, deposition of cholesterol (from trapped erythrocytes) in an area of intraplaque hemorrhage, and local exacerbation of oxidative stress. Cholesterol contained in the membrane of erythrocytes trapped in an intraplaque hemorrhage contributes to the growth of the necrotic nucleus. There is even a relationship between the amount of cholesterol in the erythrocyte membrane and the severity of atherosclerosis. In addition, the volume variability among erythrocytes, measured by RDW, is predictive of a worsening of this disease. Erythrocytes contribute to the development of atherosclerosis in several ways, especially when trapped in intraplate hemorrhage. These erythrocytes are oxidized and phagocytosed by macrophages. The cholesterol present in the membrane of these erythrocytes subsequently contributes to the growth of the atheroma plaque. In addition, when they rupture, erythrocytes release hemoglobin, which leads to the generation of free radicals. Finally, increased RDW may predict the worsening of atherosclerosis, due to the effects of inflammation and oxidative stress on erythropoiesis and erythrocyte volume. A better understanding of erythrocyte participation in atherosclerosis may contribute to the improvement of the prevention and treatment strategies of this disease.

THE EFFECTS OF INTRAVENOUS INJECTIONS OF DICHLOROETHYLSULFIDE IN RABBITS, WITH SPECIAL REFERENCE TO ITS LEUCOTOXIC ACTION

PubMed Central

Pappenheimer, Alwin M.; Vance, Morgan

1920-01-01

1. The lethal dose of dichloroethylsulfide (distilled from a German yellow cross shell), when injected intravenously into rabbits is from 0.005 to 0.01 gm. per kilo. 2. Rabbits dying within 24 hours showed extensive hemorrhages, and edema of the lungs. 3. Severe lesions of the intestinal tract were present in about one-third of the rabbits. 4. Dichloroethylsulfide injected intravenously is specifically poisonous for the hematopoietic tissues. Severe lesions are caused in the bone marrow, and the number of circulating leucocytes is markedly deminished. In animals surviving the injection regeneration occurs. The granular cells of the bone marrow seem to be more sensitive than the lymphoid cells and the erythrocytes. 5. The effect upon the blood and hematopoietic tissues is not due to the admixture of nitrobenzene or chlorobenzene in the shell filling. Injection of these substances in animals in amounts many times greater than the total dose of dichloroethylsulfide used produced no changes in the blood picture, and the subsequent injection of dichloroethylsulfide free from these solvents produced a typical reaction. PMID:19868389

Elemental X-ray mapping of agglutinated foraminifer tests: A non- destructive technique for determining compositional characteristics.

USGS Publications Warehouse

Commeau, R.F.; Reynolds, Leslie A.; Poag, C.W.

1985-01-01

The composition of agglutinated foraminiferal tests vary remarkably in response to local substrate characteristics, physiochemical properties of the water column and species- dependant selectivity of test components. We have employed a technique that combines a scanning electron microscope with an energy dispersive X-ray spectrometer system to identify major and minor elemental constituents of agglutinated foraminiferal walls. As a sample is bombarded with a beam of high energy electrons, X-rays are generated that are characteristic of the elements present. As a result, X- ray density maps can be produced for each of several elements present in the tests of agglutinated foraminifers. 

The utility of direct agglutination (DAT) and fast agglutination screening (FAST) tests in serodiagnosis of experimental microsporidiosis.

PubMed

Abou El Naga, Iman F; Gaafar, Maha R; El-Zawawy, Lobna A; El-Said, Doaa; Mossallam, Sherin F

2008-12-01

The present study was designed to evaluate the efficiency of two serodiagnostic tests; the direct agglutination test (DAT) and the fast agglutination screening test (FAST) in the diagnosis of Microsporidia in experimentally infected mice and to differentiate between different species of the parasite. The swiss albino mice were divided into non infected control and infected experimental groups which were further subdivided into ten subgroups. Ten samples of microsporidial spores were isolated from ten human stools and each one was used to infect each subgroup of mice. Stool and sera were collected weekly from each subgroup from the 1st to the 4th week post infection (PI). DAT & FAST tests, using antigen prepared from the different species of microsporidial spores were used to detect antibodies in sera of different mice subgroups. The cross reactivity of microsporidial spores with the antibodies of Cyclospora cyatenensis and Cryptosporidium parvum was investigated by DAT & FAST. The results proved that DAT & FAST were effective in detecting microsporidial antibodies in sera of experimentally infected mice from the 2nd week PI till the end of the study, without cross reactivity with C. cyatenensis or C. parvum. They failed to differentiate between different Microspoiridia species used but, they gave good interpretation and they were specific and sensitive, and did not need sophisticated equipments.

Latex agglutination inhibition card test for gentamicin assay: clinical evaluation and comparison with radioimmunoassay and bioassay.

PubMed Central

Standiford, H C; Bernstein, D; Nipper, H C; Caplan, E; Tatem, B; Hall, J S; Reynolds, J

1981-01-01

Gentamicin levels were determined in 100 serum specimens by a new latex agglutination inhibition card test, a radioimmunoassay (RIA), and a bioassay. Correlation coefficients determined by linear regression analysis demonstrated that the levels obtained by the latex agglutination inhibition card test had a high degree of correlation with the RIA and could be performed much faster and more economically when processing small numbers of specimens. The bioassay had a slightly lower degree of correlation with both the RIA and the latex test and was adversely influenced by concurrently administered antibiotics which could not be eliminated by beta-lactamase. When measuring gentamicin concentrations above 2 micrograms/ml, the coefficient of variation was less than 14% for the latex agglutination assay compared with 15% for the bioassay and 12% for RIA. The latex agglutination inhibition card test is a rapid, accurate, specific, and reproducible method for monitoring gentamicin levels in patients and is particularly applicable for laboratories processing small numbers of specimens. PMID:7247384

[Evaluation of the usefulness of the agglutination test with Mangifera indica extract for the identification of pathogenic Yersinia enterocolitica strains].

PubMed

Kałuzewski, S; Gierczyński, R; Szych, J; Jagielski, M

1997-01-01

The study was performed on 137 Y. enterocolitica strains belonging to various serological groups, including 75 03 group strains isolated form human clinical material. The agglutination test on slides was carried out on this strains using Mangifera indica extract of own production. Agglutinating preparation obtained from the seeds of M. indica agglutinated Y. enterocolitica organisms possessing the pVY plasmid and CRMOX+ phenotype in dilutions to 1.56 micrograms/ml. In identification tests conducted parallelly agglutination solution was used in concentrations of 100 and 10 micrograms/ml. All clones of Y. enterocolitica from O3 group from cultures at 37 degrees C and with CRMOX+ phenotype possessing the pVY plasmid were agglutinated by the extract. Agglutination failed to develop in the cultures of these clones incubated at 25 degrees C. Yersinia clones not containing the pVY plasmid with CRMOX- phenotype were resistant to agglutination. The virulence plasmid was found in 44 out of 75 strains of Y. enterocolitica O3 and was identified by restriction analysis after plasmid DNA digestion with Eco RI enzyme. The obtained results agreed with those of Wauters et al. in 1995 and confirmed the opinion of these authors on the usefulness of the test with M. indica agglutinin for the identification of virulent Y. enterocolitica strains.

Erythrocyte and blood antibacterial defense.

PubMed

Minasyan, Hayk

2014-06-01

It is an axiom that blood cellular immunity is provided by leukocytes. As to erythrocytes, it is generally accepted that their main function is respiration. Our research provides objective video and photo evidence regarding erythrocyte bactericidal function. Phase-contrast immersion vital microscopy of the blood of patients with bacteremia was performed, and the process of bacteria entrapping and killing by erythrocytes was shot by means of video camera. Video evidence demonstrates that human erythrocytes take active part in blood bactericidal action and can repeatedly engulf and kill bacteria of different species and size. Erythrocytes are extremely important integral part of human blood cellular immunity. a) are more numerous; b) are able to entrap and kill microorganisms repeatedly without being injured; c) are more resistant to infection and better withstand the attacks of pathogens; d) have longer life span and are produced faster; e) are inauspicious media for proliferation of microbes and do not support replication of chlamidiae, mycoplasmas, rickettsiae, viruses, etc.; and f) are more effective and uncompromised bacterial killers. Blood cellular immunity theory and traditional view regarding the function of erythrocytes in human blood should be revised.

Agglutinates as recorders of fossil soil compositions. [of Apollo 17 lunar probes

NASA Technical Reports Server (NTRS)

Taylor, G. J.; Wentworth, S.; Warner, R. D.; Keil, K.

1978-01-01

The composition of agglutinates in polished sections of the Apollo 17 drill core was studied in an attempt to deduce the nature of the Taurus-Littrow valley regolith prior to the formation of the Camelot and Central Cluster craters. The agglutinate compositions in the soils differed from the host soil compositions except for samples from the North Massif. Local materials from the valley floor and the massifs appear to form the pre-Central Cluster regolith. It is also shown that chemical mixing models for bulk soil compositions can be misleading unless the petrologic characteristics of each soil are taken into account.

Synthesis for Lunar Simulants: Glass, Agglutinate, Plagioclase, Breccia

NASA Technical Reports Server (NTRS)

Weinstein, Michael; Wilson, Stephen A.; Rickman, Douglas L.; Stoeser, Douglas

2012-01-01

The video describes a process for making glass for lunar regolith simulants that was developed from a patented glass-producing technology. Glass composition can be matched to simulant design and specification. Production of glass, pseudo agglutinates, plagioclase, and breccias is demonstrated. The system is capable of producing hundreds of kilograms of high quality glass and simulants per day.

Comparative evaluation of gel column agglutination and erythrocyte magnetized technology for red blood cell alloantibody titration.

PubMed

Dubey, Anju; Sonker, Atul; Chaudhary, Rajendra K

2015-01-01

Antibody titration is traditionally performed using a conventional test tube (CTT) method, which is subjected to interlaboratory variations because of a lack of standardization and reproducibility. The aim of this study is to compare newer methods such as get column technology (GCT) and erythrocyte magnetized technology (EMT) for antibody titration in terms of accuracy and precision. Patient serum samples that contained immunoglobin G (IgG) red blood cell (RBC) alloantibodies of a single specificity for Rh or K anitgens were identified during routine transfusion service testing and stored. Titration and scoring were performed separately by and stored. Titration and scoring were performed separately by different laboratory personnel on CTT, GCT, and EMT. Testing was performed a total of three times on each sample. Results were analyzed for accuracy and precision. A total of 50 samples were tested. Only 20 percent of samples tested with GCT shoed titers identical to CTT, whereas 48 percent of samples tested with EMT showed titers identical to CTT. Overall, the mean of th titer difference from CTT was higher using GCT (+0.31) compared with that using EMT (+0.13). Precision shown by CTT was 30 percent, EMT was 76 percent, and GCT was 92 percent on repeat testing. GCT showed higher titer values in comparison with CTT but was found to be the most precise. EMT titers were comparable to CTT, and its precision was intermediate. Further studies to validate this method are required.

Comparison of hemagglutinating, receptor-destroying, and acetylesterase activities of avirulent and virulent bovine coronavirus strains.

PubMed

Storz, J; Zhang, X M; Rott, R

1992-01-01

Hemagglutinating and acetylesterase functions as well as the 124 kDa glycoprotein were present in the highly cell-culture adapted, avirulent bovine coronavirus strain BCV-L9, in the Norden vaccine strain derived from it, and in 5 wild-type, virulent strains that multiplied in HRT-18 cells but were restricted in several types of cultured bovine cells. The BCV-L9 and the wild-type strain BCV-LY-138 agglutinated chicken and mouse erythrocytes. The acetylesterase facilitated break-down of the BCV-erythrocyte complex with chicken but only to a minimal extent with mouse erythrocytes in the receptor-destroying enzyme test. Purified preparations of the vaccine and the wild-type strains agglutinated chicken erythrocytes at low titers and mouse erythrocytes at 128 to 256 times higher titers whereas receptor destroying enzyme activity was detectable only with chicken erythrocytes. When wild-type strains were propagated in HRT cells at low passage levels, they produced 5 x 10(5) to 4.5 x 10(6) plaque forming units per 50 microliters which agglutinated erythrocytes from mice but not from chickens. Diisopropylfluoro-phosphate moderately increased the hemagglutination titers, but completely inhibited the receptor destroying enzyme of purified virus of all strains. It had virtually no influence on the plaque-forming infectivity of the different BCV strains. The acetylesterase of strain BCV-L9 reacting in the receptor-destroying enzyme test was stable for 3 h at 37 and 42 degrees C. It was inactivated within 30 min at 56 degrees C while the hemagglutinin function of this strain was stable for 3 h at 37, 42, and 56 degrees C, but it was inactivated at 65 degrees C within 1 h.

A Demonstration of Erythrocyte Membrane Asymmetry.

ERIC Educational Resources Information Center

Pederson, Philip; And Others

1985-01-01

A three-period experiment was developed to help students visualize asymmetric distribution of proteins within membranes. It includes: (1) isolating erythrocyte membranes; (2) differential labeling of intact erythrocytes and isolated erythrocyte membranes with an impermeable fluorescent dye; and (3) separating proteins by polyacrylamide gel…

Mechanisms of red blood cells agglutination in antibody-treated paper.

PubMed

Jarujamrus, Purim; Tian, Junfei; Li, Xu; Siripinyanond, Atitaya; Shiowatana, Juwadee; Shen, Wei

2012-05-07

Recent reports on using bio-active paper and bio-active thread to determine human blood type have shown a tremendous potential of using these low-cost materials to build bio-sensors for blood diagnosis. In this work we focus on understanding the mechanisms of red blood cell agglutination in the antibody-loaded paper. We semi-quantitatively evaluate the percentage of antibody molecules that are adsorbed on cellulose fibres and can potentially immobilize red blood cells on the fibre surface, and the percentage of the molecules that can desorb from the cellulose fibre surface into the blood sample and cause haemagglutination reaction in the bulk of a blood sample. Our results show that 34 to 42% of antibody molecules in the papers treated with commercial blood grouping antibodies can desorb from the fibre surface. When specific antibody molecules are released into the blood sample via desorption, haemagglutination reaction occurs in the blood sample. The reaction bridges the red cells in the blood sample bulk to the layer of red cells immobilized on the fibre surface by the adsorbed antibody molecules. The desorbed antibody also causes agglutinated lumps of red blood cells to form. These lumps cannot pass through the pores of the filter paper. The immobilization and filtration of agglutinated red cells give reproducible identification of positive haemagglutination reaction. Results from this study provide information for designing new bio-active paper-based devices for human blood typing with improved sensitivity and specificity.

P-gp expression in brown trout erythrocytes: evidence of a detoxification mechanism in fish erythrocytes.

PubMed

Valton, Emeline; Amblard, Christian; Wawrzyniak, Ivan; Penault-Llorca, Frederique; Bamdad, Mahchid

2013-12-05

Blood is a site of physiological transport for a great variety of molecules, including xenobiotics. Blood cells in aquatic vertebrates, such as fish, are directly exposed to aquatic pollution. P-gp are ubiquitous "membrane detoxification proteins" implicated in the cellular efflux of various xenobiotics, such as polycyclic aromatic hydrocarbons (PAHs), which may be pollutants. The existence of this P-gp detoxification system inducible by benzo [a] pyrene (BaP), a highly cytotoxic PAH, was investigated in the nucleated erythrocytes of brown trout. Western blot analysis showed the expression of a 140-kDa P-gp in trout erythrocytes. Primary cultures of erythrocytes exposed to increasing concentrations of BaP showed no evidence of cell toxicity. Yet, in the same BaP-treated erythrocytes, P-gp expression increased significantly in a dose-dependent manner. Brown trout P-gp erythrocytes act as membrane defence mechanism against the pollutant, a property that can be exploited for future biomarker development to monitor water quality.

Variant Rabbit Hemorrhagic Disease Virus in Young Rabbits, Spain

PubMed Central

Dalton, Kevin P.; Nicieza, Inés; Balseiro, Ana; Muguerza, María A.; Rosell, Joan M.; Casais, Rosa; Álvarez, Ángel L.

2012-01-01

Outbreaks of rabbit hemorrhagic disease have occurred recently in young rabbits on farms on the Iberian Peninsula where rabbits were previously vaccinated. Investigation identified a rabbit hemorrhagic disease virus variant genetically related to apathogenic rabbit caliciviruses. Improved antivirus strategies are needed to slow the spread of this pathogen. PMID:23171812

Development of enhancing agglutination reaction using gold nanoparticle for pre-transfusion testing.

PubMed

Choktaweesak, N; Krasathong, P; Ammaranond, P

2016-10-01

To explore an alternative way for antibody detection testing, the examination of gold nanoparticle solution for enhancing unexpected antibodies for pre-transfusion testing was investigated. Exposure of foreign antigens on red blood cells from transfusion can trigger the immune system to produce unexpected antibodies. This immunological response may cause the complication to future transfusion. For detection of unexpected antibodies, the antibody screening test is performed approximately 30-60 min. To reduce turnaround time, enhancing reagent, low-ionic strength solution (LISS), is widely used. However, cost of enhancing reagent is an issue which has concerned in resource limited countries. Gold nanoparticle solution can increase red blood cells agglutination reaction. To solve this issue, study of gold nanoparticle solution was investigated. Samples were performed comparing between LISS and gold nanoparticle solution at antiglobulin phase. After reading the agglutination reaction, supernatants were collected and measured at the optical density at 760 nm by spectrophotometer. The optical density in the tube of gold nanoparticle solution was higher than in the tube of 2-5% cell suspension and monoclonal antibody. It has been observed that gold nanoparticle solution enhanced the reaction of agglutination 98% while LISS enhanced the agglutination only 60·8%. Employing a commercially available enhancing reagent, parallel samples confirmed results providing validation of the assay. It approximately costs $1 US dollars compared to $30 for a commercially available reagent. The low cost and yet effective time-consuming test for antibody screening is a practical and viable solution alternative way for performing in antibody screening test in resource limited countries. © 2016 British Blood Transfusion Society.

Evaluation of the usefulness of six commercial agglutination assays for serologic diagnosis of toxoplasmosis.

PubMed

Villard, Odile; Cimon, Bernard; Franck, Jacqueline; Fricker-Hidalgo, Hélène; Godineau, Nadine; Houze, Sandrine; Paris, Luc; Pelloux, Hervé; Villena, Isabelle; Candolfi, Ermanno

2012-07-01

Six agglutination tests for detecting Toxoplasma gondii-specific antibodies (immunoglobulin G or M) in serum were performed and compared. In total, 599 sera were examined using direct and indirect agglutination assays. Sensitivity varied from 93.7% to 100% and specificity from 97.1% to 99.2%. In a selected population with interfering diseases, the percentage of false positives ranged from 4.3% to 10.9%. Although an overall agreement of 100% was found for chronic toxoplasmosis, sensitivity for the detection of confirmed acute toxoplasmosis ranged from 86.4% to 97.3%. Regarding the large variability in terms of the performance of the 6 assays, tests based on the hemagglutination principle were found to be better than the other agglutination tests for all the panels evaluated, meaning that they could be used as qualitative or semiquantitative low-cost screening assays. Copyright © 2012 Elsevier Inc. All rights reserved.

Typhoid fever in a Tertiary Hospital in Nigeria: Another look at the Widal agglutination test as a preferred option for diagnosis.

PubMed

Enabulele, Osahon; Awunor, Simeon Nyemike

2016-01-01

Single Widal agglutination test rather than blood culture, is commonly employed to diagnose typhoid fever in Nigeria. We took another look at the Widal agglutination test as a preferred option for diagnosis of typhoid fever by determining the specificity and sensitivity of Widal agglutination test in febrile adult patients. Two hundred and seventy-one blood samples from consecutive adults (>18 years) with febrile illness attending the General Practice Clinic of the University of Benin Teaching Hospital were tested using the Widal agglutination test, blood culture, and malaria parasite test on each sample to establish the diagnosis of typhoid fever. Of the 271 blood samples 124 (45.76%) were positive following a Widal agglutination test, 60 (22.10%) blood samples grew Salmonella organisms on blood culture while 55 (20.29%) blood samples showed a co-infection of typhoid fever and malaria. A sensitivity of 35%, specificity of 51%, positive predictive value of 17%, and a negative predictive value of 73% were observed for Widal agglutination test as a diagnostic modality for typhoid fever infection. A single Widal agglutination test is not a valid diagnostic option for typhoid fever while co-infection with malaria parasite is the preponderant microbiological finding in typhoid fever infections. The severity of malaria parasitemia is associated with positive titers on Widal test.

Antigenic and functional characterization of p57 produced by Renibacterium salmoninarum

USGS Publications Warehouse

Weins, G.; Chien, M.S.; Winton, J.R.; Kaatari, S.L.

1999-01-01

Renibacterium salmoninarum, the causative agent of bacterial kidney disease, produces large quantities of a 57-58 kDa protein (p57) during growth in broth culture and during infection of salmonid fish. Biological activities of secreted p57 include agglutination of salrnonid leucocytes and rabbit erythrocytes. We define the location of epitopes on p57 recognized by agglutination-blocking monoclonal antibodies (MAbs) 4Cl1, 4H8 and 4D3, and demonstrate that the majority of secreted p57 is a nlonomer that retains salrnonid leucocyte agglutinat~ng activity. The 3 MAbs bound a recombinant, amino-terminal fragment of p57 (211 aa) but not a carboxy-terminal fragment (315 aa) demonstrating that the neutralizing epitopes are located within the amino-terminal portion of p57. When combinations of the MAbs were used in an antigen capture ELISA. the epitopes recognized by the 3 MAbs were shown to be sterically separate. However, when the same MAb was used as both the coating and detection MAb, binding of the biotinylated detection MAb was not observed. These data indicate that the epitopes recognized by the 3 agglutination-blocking antibodies are functionally available only once per molecule and that native p57 exists as a monomer Similar ELISA results were obtained when kidney tissues from 3 naturally infected chinook salmon were assayed. Finally, a p57 monomer was purified using anion exchange and size exclusion chromatography that retained in vitro agglutinating activity. A model in which p57 is released from R. salmoninarum as a biologically active monomer during infection of salmonid fish is proposed.

Tocopherol transport in the rat erythrocyte

PubMed Central

Silber, R.; Winter, R.; Kayden, H. J.

1969-01-01

The transport of vitamin E (α-tocopherol) has been studied in the rat erythrocyte in vivo and in vitro. Uptake and efflux are independent of energy, but sensitive to temperature. Tocopherol is localized to the cell membrane. Rapid exchange takes place between erythrocytes and serum with an hourly fractional tocopherol efflux of 26%. The vitamin is transferred from the erythrocyte to the low density lipoproteins. These experiments indicate that tocopherol, like cholesterol, is a constituent of the erythrocyte membrane which is in dynamic equilibrium with the corresponding plasma compound. PMID:5824074

STUDIES OF TWO KINDS OF VIRUS PARTICLES WHICH COMPRISE INFLUENZA A2 VIRUS STRAINS

PubMed Central

Choppin, Purnell W.; Tamm, Igor

1960-01-01

Two kinds of virus particles have been found in varying proportions in influenza A2 strains isolated during the 1957 pandemic. Pure populations of the different particles were obtained, and these substrains were genetically stable on serial passage in the chick embryo. The two virus particles differ markedly in several biological properties though they are antigenically similar. One kind of particle, designated "+," is relatively sensitive to specific antibody, is highly sensitive to inhibition by serum inhibitors and urinary mucoprotein, fails to elute or elutes very slowly from human erythrocytes, and is capable of agglutinating erythrocytes treated extensively with V. cholerae filtrate. The other particle, designated "-," is relatively insensitive to antibodies and urinary mucoprotein, completely insensitive to serum inhibitors, elutes rapidly from erythrocytes, and can agglutinate erythrocytes treated extensively with V. cholerae filtrate. Both "+" and "-" particles destroy virus receptors on urinary mucoprotein. The relative proportions of these two particles determine the characteristics of parent strains in reactions with specific antibody, mucoprotein inhibitors, and erythrocytes. The "+" and "-" particles with several easily identifiable markers are well suited for genetic studies. PMID:19867182

The value of automated gel column agglutination technology in the identification of true inherited D blood types in massively transfused patients.

PubMed

Summers, Thomas; Johnson, Viviana V; Stephan, John P; Johnson, Gloria J; Leonard, George

2009-08-01

Massive transfusion of D- trauma patients in the combat setting involves the use of D+ red blood cells (RBCs) or whole blood along with suboptimal pretransfusion test result documentation. This presents challenges to the transfusion service of tertiary care military hospitals who ultimately receive these casualties because initial D typing results may only reflect the transfused RBCs. After patients are stabilized, mixed-field reaction results on D typing indicate the patient's true inherited D phenotype. This case series illustrates the utility of automated gel column agglutination in detecting mixed-field reactions in these patients. The transfusion service test results, including the automated gel column agglutination D typing results, of four massively transfused D- patients transfused D+ RBCs is presented. To test the sensitivity of the automated gel column agglutination method in detecting mixed-field agglutination reactions, a comparative analysis of three automated technologies using predetermined mixtures of D+ and D- RBCs is also presented. The automated gel column agglutination method detected mixed-field agglutination in D typing in all four patients and in the three prepared control specimens. The automated microwell tube method identified one of the three prepared control specimens as indeterminate, which was subsequently manually confirmed as a mixed-field reaction. The automated solid-phase method was unable to detect any mixed fields. The automated gel column agglutination method provides a sensitive means for detecting mixed-field agglutination reactions in the determination of the true inherited D phenotype of combat casualties transfused massive amounts of D+ RBCs.

Latex agglutination test (LAT) for the diagnosis of typhoid fever.

PubMed

Sahni, Gopal Shankar

2013-06-01

The efficacy of latex agglutination test in the rapid diagnosis of typhoid fever was studied and the result compared with that of blood culture. This study included 80 children suffering from typhoid fever, among which 40 were confirmed by blood culture isolation and 40 had possible typhoid fever based on high Widal's titre (a four-fold rise in the titre of antibody to typhi "O" and "H" antigen was considered as a positive Widal's test result). Eighty children, 40 with febrile illness confirmed to be other than typhoid and 40 normal healthy children were used as negative controls. The various groups were: (i) Study group ie, group I had 40 children confirmed by culture isolation of Salmonella typhi(confirmed typhoid cases). (ii) Control groups ie, (a) group II with 40 febrile controls selected from paediatrics ward where cause other than S typhi has been established, (b) group III with 40 afebrile healthy controls that were siblings of the children admitted in paediatric ward for any reason with no history of fever and TAB vaccination in the last one year, and (c) group IV with 40 children with high Widal's titre in paired sera sample. Widal's test with paired sera with a one week interval between collections were done in all 40 patients. Latex aggtutination test which could detect 900 ng/ml of antigen as observed in checker board titration, was positive in all 40 children from group I who had positive blood culture and in 30 children from group IV who had culture negative and had high Widal's titre positive. Latex agglutination test was positive in 4 children in group II and none in group III. Using blood culture positive cases as true positive and children in groups II and III as true negative, the test had a sensitivity of 100% and specificity of 96%. Latex agglutination test was found to be significantly sensitive (100%) and specific (96%) and could detect 75% more cases in group IV (possible typhoid cases). Thus latex agglutination test can be used for rapid

Pneumonic Tularemia in Rabbits Resembles the Human Disease as Illustrated by Radiographic and Hematological Changes after Infection

PubMed Central

Reed, Douglas S.; Smith, Le'Kneitah; Dunsmore, Tammy; Trichel, Anita; Ortiz, Luis A.; Cole, Kelly Stefano; Barry, Eileen

2011-01-01

Background Pneumonic tularemia is caused by inhalation of the gram negative bacterium, Francisella tularensis. Because of concerns that tularemia could be used as a bioterrorism agent, vaccines and therapeutics are urgently needed. Animal models of pneumonic tularemia with a pathophysiology similar to the human disease are needed to evaluate the efficacy of these potential medical countermeasures. Principal Findings Rabbits exposed to aerosols containing Francisella tularensis strain SCHU S4 developed a rapidly progressive fatal pneumonic disease. Clinical signs became evident on the third day after exposure with development of a fever (>40.5°C) and a sharp decline in both food and water intake. Blood samples collected on day 4 found lymphopenia and a decrease in platelet counts coupled with elevations in erythrocyte sedimentation rate, alanine aminotransferase, cholesterol, granulocytes and monocytes. Radiographs demonstrated the development of pneumonia and abnormalities of intestinal gas consistent with ileus. On average, rabbits were moribund 5.1 days after exposure; no rabbits survived exposure at any dose (190–54,000 cfu). Gross evaluation of tissues taken at necropsy showed evidence of pathology in the lungs, spleen, liver, kidney and intestines. Bacterial counts confirmed bacterial dissemination from the lungs to the liver and spleen. Conclusions/Significance The pathophysiology of pneumonic tularemia in rabbits resembles what has been reported for humans. Rabbits therefore are a relevant model of the human disease caused by type A strains of F. tularensis. PMID:21931798

[Ceruloplasmin receptor on human erythrocytes].

PubMed

Saenko, E L; Basevich, V V; Iaropolov, A I

1988-08-01

The structural fragments of the human ceruloplasmin (CP) molecule and of erythrocyte receptors which provide for the specific interaction of CP with erythrocytes were identified, and their properties were investigated. The interaction of CP with erythrocytes, both intact and treated with neuroaminidase and proteolytic enzymes (trypsin, chymotrypsin, papaine, pronase E) is described. Experiments with CP reception were performed at 4 degrees C, using [125I]CP and [125I]asialo-CP. The parameters of binding were determined in Scatchard plots. It was demonstrated that the specific binding of CP to erythrocyte receptors is determined by its interaction with two structural sites of the carbohydrate moiety of the CP molecule, i.e., the terminal residues of sialic acids and a site, (formula; see text) located at a large distance from the chain terminus.

Typhoid fever in a Tertiary Hospital in Nigeria: Another look at the Widal agglutination test as a preferred option for diagnosis

PubMed Central

Enabulele, Osahon; Awunor, Simeon Nyemike

2016-01-01

Background: Single Widal agglutination test rather than blood culture, is commonly employed to diagnose typhoid fever in Nigeria. We took another look at the Widal agglutination test as a preferred option for diagnosis of typhoid fever by determining the specificity and sensitivity of Widal agglutination test in febrile adult patients. Materials and Methods: Two hundred and seventy-one blood samples from consecutive adults (>18 years) with febrile illness attending the General Practice Clinic of the University of Benin Teaching Hospital were tested using the Widal agglutination test, blood culture, and malaria parasite test on each sample to establish the diagnosis of typhoid fever. Results: Of the 271 blood samples 124 (45.76%) were positive following a Widal agglutination test, 60 (22.10%) blood samples grew Salmonella organisms on blood culture while 55 (20.29%) blood samples showed a co-infection of typhoid fever and malaria. A sensitivity of 35%, specificity of 51%, positive predictive value of 17%, and a negative predictive value of 73% were observed for Widal agglutination test as a diagnostic modality for typhoid fever infection. Conclusion: A single Widal agglutination test is not a valid diagnostic option for typhoid fever while co-infection with malaria parasite is the preponderant microbiological finding in typhoid fever infections. The severity of malaria parasitemia is associated with positive titers on Widal test. PMID:27397952

Construction of live vaccines by using genetically engineered poxviruses: biological activity of recombinant vaccinia virus expressing influenza virus hemagglutinin.

PubMed Central

Panicali, D; Davis, S W; Weinberg, R L; Paoletti, E

1983-01-01

Recombinant vaccinia viruses containing the cloned hemagglutinin (HA) gene from influenza virus were constructed. The biological activity of these poxvirus vectors was demonstrated both in vitro and in vivo. Expression of HA in cells infected with recombinant vaccinia was detected by using specific anti-HA antiserum and 125I-labeled protein A, showing that HA synthesized under the regulation of vaccinia virus was antigenic. Immunization of rabbits with these recombinant poxviruses resulted in the production of antibodies reactive with authentic influenza HA as detected by radioimmunoassay, by inhibition of HA erythrocyte agglutination, and by neutralization of influenza virus infectivity. The production of antibodies directed against influenza HA suggested that the HA gene expressed in vaccinia is immunogenic. These data indicate the potential of genetically engineered poxviruses for use as generic live vaccine vehicles that have both human and veterinary applications. Images PMID:6310573

The relationship of the lunar regolith less than 10 micrometer fraction and agglutinates. I - A model for agglutinate formation and some indirect supportive evidence

NASA Technical Reports Server (NTRS)

Papike, J. J.; Simon, S. B.; White, C.; Laul, J. C.

1982-01-01

The first part of a study of the 'less than 10 micrometer' soil fraction and agglutinates is concerned with the chemical systematics of the considered fraction of lunar soils, taking into account a model for agglutinate formation based on the fusion of the finest fraction (FFF). Attention is given to some evidence which supports the FFF model. The evidence is based on some indirect approaches to an estimation of the composition of the fused soil component. It is found that the 'less than 10 micrometer' soil fraction from all Apollo sites except Apollo 16 (which can be explained) is more feldspathic and enriched in incompatible elements (e.g., K and Th) than the bulk soil. It is concluded that these systematics result from simple comminution in which feldspar breaks down to finer sizes than pyroxene and olivine and the fine-grained incompatible-element-enriched mesostasis concentrates in the 'less than 10 micrometer' soil fraction.

The relationship between fluorescent, agglutinating, and precipitating antibodies to Candida albicans and their immunoglobin classes

PubMed Central

Lehner, T.; Buckley, Helen R.; Murray, I. G.

1972-01-01

A parallel study of fluorescent, agglutinating, and precipitating antibodies to Candida albicans revealed that precipitating antibodies belong to the IgG class, whereas agglutinating antibodies reside in the IgG, IgM, and IgA classes. The three types as well as the three classes of antibodies were found in Candida endocarditis and mucocutaneous candidiasis. Immuno-absorption studies suggest that the three serological tests estimate antibodies to mannan determinants of Candida albicans. Images PMID:4555044

Pheromone induction of agglutination in Saccharomyces cerevisiae a cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Terrance, K.; Lipke, P.N.

1987-10-01

a-Agglutinin, the cell surface sexual agglutinin of yeast a cells, was assayed by its ability to bind its complementary agglutinin, ..cap alpha..-agglutinin. The specific binding of /sup 125/I-..cap alpha..-agglutinin to a cells treated with the sex pheromone ..cap alpha..-factor was 2 to 2.5 times that of binding to a cells not treated with ..cap alpha..-factor. Competition with unlabeled ..cap alpha..-agglutinin revealed that the increased binding was due to increased cell surface expression of a-agglutinin, with no apparent change in the binding constant. The increase in site number was similar to the increase in cellular agglutinability. Increased expression of a-agglutinin followedmore » the same kinetics as the increase in cellular agglutinability, with a 10-min lag followed by a 15- to 20-min response time. Induction kinetics were similar in cells in phases G1 and G2 of the cell cycle. Maximal expression levels were similar in cells treated with excess pheromone and in cells exposed to pheromone after destruction of constitutively expressed a-agglutinin.« less

The mechanism of erythrocyte sedimentation. Part 2: The global collapse of settling erythrocyte network.

PubMed

Pribush, A; Meyerstein, D; Meyerstein, N

2010-01-01

Results reported in the companion paper showed that erythrocytes in quiescent blood are combined into a network followed by the formation of plasma channels within it. This study is focused on structural changes in the settling dispersed phase subsequent to the channeling and the effect of the structural organization on the sedimentation rate. It is suggested that the initial, slow stage of erythrocyte sedimentation is mainly controlled by the gravitational compactness of the collapsed network. The lifetime of RBC network and hence the duration of the slow regime of erythrocyte sedimentation decrease with an increase in the intercellular pair potential and with a decrease in Hct. The gravitational compactness of the collapsed network causes its rupture into individual fragments. The catastrophic collapse of the network transforms erythrocyte sedimentation from slow to fast regime. The size of RBC network fragment is insignificantly affected by Hct and is mainly determined by the intensity of intercellular attractive interactions. When cells were suspended in the weak aggregating medium, the Stokes radius of fragments does not differ measurably from that of individual RBCs. The proposed mechanism provides a reasonable explanation of the effects of RBC aggregation, Hct and the initial height of the blood column on the delayed erythrocyte sedimentation.

Erythrocyte fluorescence and lead intoxication.

PubMed Central

Clark, K G

1976-01-01

Blood samples from people exposed to inorganic lead were examined by fluorescence microscopy for excess erythrocyte porphyrin. With continued lead absorption, fluorescent erythrocytes appeared in the circulation of workers handling this metal or its compounds, and they progressively increased in number and brilliance. These changes ensued if the blood lead concentration was maintained above 2-42 mumol/l (50 mug/100 ml), and preceded any material fall in the haemoglobin value. At one factory, 62-5% of 81 symptomless workers showed erythrocyte fluorescence attributable to the toxic effects of lead. Excess fluorocytes were found in blood samples from a child with pica and three of her eight siblings. These four were subsequently shown to have slightly increased blood lead concentrations (2-03 to 2-32 mumol/l). Fluorescence microscopy for excess erythrocyte porphyrin is a sensitive method for the detection of chronic lead intoxication. A relatively slight increase in the blood lead is associated with demonstrabel changes in erythrocyte porphyrin content. The procedure requires little blood, and may be performed upon stored samples collected for lead estimation. The results are not readily influenced by contamination, and provide good confirmatory evidence for the absorption of biochemically active lead. PMID:963005

Erythrocyte ion channels in regulation of apoptosis.

PubMed

Lang, Florian; Birka, Christina; Myssina, Svetlana; Lang, Karl S; Lang, Philipp A; Tanneur, Valerie; Duranton, Christophe; Wieder, Thomas; Huber, Stephan M

2004-01-01

Erythrocytes lack mitochondria and nuclei, key organelles in the regulation of apoptosis. Until recently, erythrocytes were thus not considered subject to this type of cell death. However, exposure of erythrocytes to the Ca2+ ionophore ionomycin was shown to induce cell shrinkage, cell membrane blebbing and breakdown of phosphatidylserine asymmetry with subsequent phosphatidylserine exposure at the cell surface, all typical features of apoptosis. Further studies revealed the participation of ion channels in the regulation of erythrocyte "apoptosis." Osmotic shock, oxidative stress and energy depletion all activate a Ca2(+)-permeable non-selective cation channel in the erythrocyte cell membrane. The subsequent increase of Ca2+ concentration stimulates a scramblase leading to breakdown of cell membrane phosphatidylserine asymmetry and activates Ca2+ sensitive K+ (Gardos) channels leading to KCl loss and (further) cell shrinkage. Phosphatidylserine exposure and cell shrinkage are blunted in the nominal absence of extracellular Ca2+, in the presence of the cation channel inhibitors amiloride or ethylisopropylamiloride, at increased extracellular K+ or in the presence of the Gardos channel inhibitors clotrimazole or charybdotoxin. Thus, increase of cytosolic Ca2+ and cellular loss of K+ participate in the triggering of erythrocyte scramblase. Nevertheless, phosphatidylserine exposure is not completely abrogated in the nominal absence of Ca2+, pointing to additional Ca2(+)-independent pathways. One of those is activation of sphingomyelinase with subsequent formation of ceramide which in turn leads to stimulation of erythrocyte scramblase. The exposure of phosphatidylserine at the extracellular face of the cell membrane stimulates phagocytes to engulf the apoptotic erythrocytes. Thus, sustained activation of the cation channels eventually leads to clearance of affected erythrocytes from peripheral blood. Erythropoietin inhibits the non-selective cation channel and thus

A low cost and high throughput magnetic bead-based immuno-agglutination assay in confined droplets.

PubMed

Teste, Bruno; Ali-Cherif, Anaïs; Viovy, Jean Louis; Malaquin, Laurent

2013-06-21

Although passive immuno-agglutination assays consist of one step and simple procedures, they are usually not adapted for high throughput analyses and they require expensive and bulky equipment for quantitation steps. Here we demonstrate a low cost, multimodal and high throughput immuno-agglutination assay that relies on a combination of magnetic beads (MBs), droplets microfluidics and magnetic tweezers. Antibody coated MBs were used as a capture support in the homogeneous phase. Following the immune interaction, water in oil droplets containing MBs and analytes were generated and transported in Teflon tubing. When passing in between magnetic tweezers, the MBs contained in the droplets were magnetically confined in order to enhance the agglutination rate and kinetics. When releasing the magnetic field, the internal recirculation flows in the droplet induce shear forces that favor MBs redispersion. In the presence of the analyte, the system preserves specific interactions and MBs stay in the aggregated state while in the case of a non-specific analyte, redispersion of particles occurs. The analyte quantitation procedure relies on the MBs redispersion rate within the droplet. The influence of different parameters such as magnetic field intensity, flow rate and MBs concentration on the agglutination performances have been investigated and optimized. Although the immuno-agglutination assay described in this work may not compete with enzyme linked immunosorbent assay (ELISA) in terms of sensitivity, it offers major advantages regarding the reagents consumption (analysis is performed in sub microliter droplet) and the platform cost that yields to very cheap analyses. Moreover the fully automated analysis procedure provides reproducible analyses with throughput well above those of existing technologies. We demonstrated the detection of biotinylated phosphatase alkaline in 100 nL sample volumes with an analysis rate of 300 assays per hour and a limit of detection of 100 pM.

Determination of degree of RBC agglutination for blood typing using a small quantity of blood sample in a microfluidic system.

PubMed

Chang, Yaw-Jen; Ho, Ching-Yuan; Zhou, Xin-Miao; Yen, Hsiu-Rong

2018-04-15

Blood typing assay is a critical test to ensure the serological compatibility of a donor and an intended recipient prior to a blood transfusion. This paper presents a microfluidic blood typing system using a small quantity of blood sample to determine the degree of agglutination of red blood cell (RBC). Two measuring methods were proposed: impedimetric measurement and electroanalytical measurement. The charge transfer resistance in the impedimetric measurement and the power parameter in the electroanalytical measurement were used for the analysis of agglutination level. From the experimental results, both measuring methods provide quantitative results, and the parameters are linearly and monotonically related to the degree of RBC agglutination. However, the electroanalytical measurement is more reliable than the impedimetric technique because the impedimetric measurement may suffer from many influencing factors, such as chip conditions. Five levels from non-agglutination (level 0) to strong agglutination (level 4+) can be discriminated in this study, conforming to the clinical requirement to prevent any risks in transfusion. Copyright © 2017 Elsevier B.V. All rights reserved.

Calcium transport in the early conceptus and associated maternal tissues in the rabbit

PubMed Central

McIntosh, J. E. A.; Lutwak-Mann, C.

1974-01-01

1. The kinetics of calcium transport were studied in unmated (oestrous) and pregnant rabbits in the first half of gestation, with the aim of establishing evidence of hormonal (ovarian) influence on the pattern of transport. 2. The following tissues were examined at short- (45min and 2h) and long-duration (4, 16 and 48h) intervals after parenteral administration of 45Ca or 47Ca: maternal blood plasma, endometrium, uterine fluid, placental tissues, two developmentally disparate stages of rabbit conceptus, namely the unattached blastocyst and the early post-implantation foetus, and bone (femur). 3. Marked variability in calcium content characterized rabbit tissues and body fluids. 4. Compartmental analysis was applied to measurements of specific radioactivity. Oestrous endometrium had the largest rapidly exchanging calcium fraction (turnover time of 12min) and the highest value for calcium flux (500μg of Ca exchanged/h per g fresh wt. of tissue). A marked downward gradient in values of flux existed between the progestational endometrium, uterine fluid and blastocyst; there was a similar gradient between placental tissues and foetus. 5. An hormonal influence on calcium transport was evident in (i) the decrease in specific radioactivity of rabbit blood plasma with advancing pregnancy, (ii) the extraordinarily rapid calcium transport between blood plasma and endometrium, especially in the oestrous stage, and (iii) the effectiveness of ovarian hormone substitution in ovariectomized rabbits. 6. The very low specific radioactivity recorded for bone indicated that only a minute fraction of its calcium was exchanging with that of blood plasma under the experimental conditions examined. 7. The rate of uptake of 45Ca by rabbit blastocysts growing in vitro was one-tenth of that of 22Na, or that recorded for calcium in vivo. 8. Inhibition of carbonic anhydrase activity with acetazolamide in vivo, in maternal erythrocytes, endometrium and placental tissues, produced no

[Yes, we should keep ABO agglutination test within bedside transfusion checks].

PubMed

Daurat, G

2008-11-01

ABO incompatible transfusions are still a frequent cause of serious adverse transfusion reactions. Bedside check is intended to detect patient errors and prevent ABO mismatch. France is one of the few countries that includes ABO agglutination test for red blood cells in bedside checks. Evaluation of this ABO agglutination test, performed with a special card, shows that, on the field, despite frequent users' mishandling, it can detect up to 93% of ABO incompatibilities. This is not enough to rely on this sole test for bedside checks. But, linking it with an another test, currently, checks that the right blood is given to the right patient, rises the sensitivity of the whole bedside procedure up to an estimated 99.65%, for detection of ABO incompatibilities. This linkage has been introduced in the French regulation in 2003. Since then, the incidence of ABO incompatible transfusions has decreased dramatically and faster than in any other country, so France has now, probably, the lowest rate of ABO incompatible transfusions. The investigation of the few ABO accidents that still occur, shows that professionals have always bypassed this linkage. On the other hand, introducing bedside recipient and blood products barcode or radio-chip checks in all the 1500 French hospitals, though technically possible, would provide very little enhancement and lead to major difficulties and expenses. Linkage of ABO agglutination test to patient and blood checks within the bedside procedure has proved to be efficient and should be kept.

Construction of Recombinant Hemagglutinin Derived from the Gingipain-Encoding Gene of Porphyromonas gingivalis, Identification of Its Target Protein on Erythrocytes, and Inhibition of Hemagglutination by an Interdomain Regional Peptide▿

PubMed Central

Sakai, Eiko; Naito, Mariko; Sato, Keiko; Hotokezaka, Hitoshi; Kadowaki, Tomoko; Kamaguchi, Arihide; Yamamoto, Kenji; Okamoto, Kuniaki; Nakayama, Koji

2007-01-01

Porphyromonas gingivalis, an anaerobic gram-negative bacterium associated with chronic periodontitis, can agglutinate human erythrocytes. In general, hemagglutination can be considered the ability to adhere to host cells; however, P. gingivalis-mediated hemagglutination has special significance because heme markedly accelerates growth of this bacterium. Although a number of studies have indicated that a major hemagglutinin of P. gingivalis is intragenically encoded by rgpA, kgp, and hagA, direct evidence has not been obtained. We demonstrated in this study that recombinant HGP44720-1081, a fully processed HGP44 domain protein, had hemagglutinating activity but that an unprocessed form, HGP44720-1138, did not. A peptide corresponding to residues 1083 to 1102, which was included in HGP44720-1138 but not in HGP44720-1081, could bind HGP44720-1081 in a dose-dependent manner and effectively inhibited HGP44720-1081-mediated hemagglutination, indicating that the interdomain regional amino acid sequence may function as an intramolecular suppressor of hemagglutinating activity. Analyses by solid-phase binding and chemical cross-linking suggested that HGP44 interacted with glycophorin A on the erythrocyte membrane. Glycophorin A and, more effectively, asialoglycophorin, which were added exogenously, inhibited HGP44720-1081-mediated hemagglutination. Treatment of erythrocytes with RgpB proteinase resulted in degradation of glycophorin A on the membrane and a decrease in HGP44720-1081-mediated hemagglutination. Surface plasmon resonance detection analysis revealed that HGP44720-1081 could bind to asialoglycophorin with a dissociation constant of 3.0 × 10−7 M. These results indicate that the target of HGP44 on the erythrocyte membrane appears to be glycophorin A. PMID:17384191

Effects of Hemagglutination Activity in the Serum of a Deep-Sea Vent Endemic Crab, Shinkaia Crosnieri, on Non-Symbiotic and Symbiotic Bacteria

PubMed Central

Fujiyoshi, So; Tateno, Hiroaki; Watsuji, Tomoo; Yamaguchi, Hideyuki; Fukushima, Daisuke; Mino, Sayaka; Sugimura, Makoto; Sawabe, Tomoo; Takai, Ken; Sawayama, Shigeki; Nakagawa, Satoshi

2015-01-01

In deep-sea hydrothermal environments, most invertebrates associate with dense populations of symbiotic microorganisms in order to obtain nutrition. The molecular interactions between deep-sea animals and environmental microbes, including their symbionts, have not yet been elucidated in detail. Hemagglutinins/lectins, which are carbohydrate-binding proteins, have recently been reported to play important roles in a wide array of biological processes, including the recognition and control of non-self materials. We herein assessed hemagglutination activity in the serum of a deep-sea vent endemic crab, Shinkaia crosnieri, which harbors chemosynthetic epibionts on its plumose setae. Horse and rabbit erythrocytes were agglutinated using this serum (opt. pH 7.5 and opt. temperature 15°C). Agglutinating activity was inhibited by eight kinds of sugars and several divalent cations, did not require any divalent metal ions, and remained detectable even after heating the serum at 100°C for 30 min. By using fluorescently labeled serum, we demonstrated that deep-sea crab serum components bound to the epibionts even in the presence of sugars. This study represents the first immunological assessment of a deep-sea vent endemic crab and demonstrated the possibility of a non-lectin-mediated symbiont-host interaction. PMID:26212518

Interaction of Clostridium perfringens delta toxin with erythrocyte and liposome membranes and relation with the specific binding to the ganglioside GM2.

PubMed

Jolivet-Reynaud, C; Hauttecoeur, B; Alouf, J E

1989-01-01

The specific interaction of the cytolytic Clostridium perfringens delta toxin with membrane GM2 was indicated by: (i) characterization of this glycolipid in the membrane of sheep and goat erythrocytes, which are lysed by the toxin, whereas GM2 was undetectable in insensitive rabbit erythrocytes, (ii) demonstration of 125I-toxin binding to GM2, by autoradiography, following incubation with thin-layer chromatograms containing separated neuroblastoma gangliosides, and (iii) toxin fixation by phospholipid-cholesterol unilamellar vesicles containing either sheep gangliosides or GM2. In order to investigate the intramembrane events leading to membrane disruption following toxin binding, the photoreactive probe 12(4-azido-2-nitrophenoxy)stearoyl 1-14C glucosamine, which inserts into the outer layer and labels integral membrane proteins, was used to establish whether delta toxin penetrates into target cell membrane. No toxin labeling was found, suggesting that toxin action takes place at the membrane surface. This contention is supported by the observation that despite toxin binding, GM2 liposomes did not release entrapped 14C-glucose. Treatment of toxin with carboxypeptidases, but not aminopeptidases, abolished both toxin binding capacity onto erythrocytes and its combination with antitoxin neutralizing antibodies, suggesting that the carboxy terminal end of the toxin is critical for binding to cell membrane.

Antimicrobial Action and Cell Agglutination by the Eosinophil Cationic Protein Are Modulated by the Cell Wall Lipopolysaccharide Structure

PubMed Central

Pulido, David; Moussaoui, Mohammed; Andreu, David; Nogués, M. Victòria

2012-01-01

Antimicrobial proteins and peptides (AMPs) are essential effectors of innate immunity, acting as a first line of defense against bacterial infections. Many AMPs exhibit high affinity for cell wall structures such as lipopolysaccharide (LPS), a potent endotoxin able to induce sepsis. Hence, understanding how AMPs can interact with and neutralize LPS endotoxin is of special relevance for human health. Eosinophil cationic protein (ECP) is an eosinophil secreted protein with high activity against both Gram-negative and Gram-positive bacteria. ECP has a remarkable affinity for LPS and a distinctive agglutinating activity. By using a battery of LPS-truncated E. coli mutant strains, we demonstrate that the polysaccharide moiety of LPS is essential for ECP-mediated bacterial agglutination, thereby modulating its antimicrobial action. The mechanism of action of ECP at the bacterial surface is drastically affected by the LPS structure and in particular by its polysaccharide moiety. We have also analyzed an N-terminal fragment that retains the whole protein activity and displays similar cell agglutination behavior. Conversely, a fragment with further minimization of the antimicrobial domain, though retaining the antimicrobial capacity, significantly loses its agglutinating activity, exhibiting a different mechanism of action which is not dependent on the LPS composition. The results highlight the correlation between the protein's antimicrobial activity and its ability to interact with the LPS outer layer and promote bacterial agglutination. PMID:22330910

Antimicrobial action and cell agglutination by the eosinophil cationic protein are modulated by the cell wall lipopolysaccharide structure.

PubMed

Pulido, David; Moussaoui, Mohammed; Andreu, David; Nogués, M Victòria; Torrent, Marc; Boix, Ester

2012-05-01

Antimicrobial proteins and peptides (AMPs) are essential effectors of innate immunity, acting as a first line of defense against bacterial infections. Many AMPs exhibit high affinity for cell wall structures such as lipopolysaccharide (LPS), a potent endotoxin able to induce sepsis. Hence, understanding how AMPs can interact with and neutralize LPS endotoxin is of special relevance for human health. Eosinophil cationic protein (ECP) is an eosinophil secreted protein with high activity against both Gram-negative and Gram-positive bacteria. ECP has a remarkable affinity for LPS and a distinctive agglutinating activity. By using a battery of LPS-truncated E. coli mutant strains, we demonstrate that the polysaccharide moiety of LPS is essential for ECP-mediated bacterial agglutination, thereby modulating its antimicrobial action. The mechanism of action of ECP at the bacterial surface is drastically affected by the LPS structure and in particular by its polysaccharide moiety. We have also analyzed an N-terminal fragment that retains the whole protein activity and displays similar cell agglutination behavior. Conversely, a fragment with further minimization of the antimicrobial domain, though retaining the antimicrobial capacity, significantly loses its agglutinating activity, exhibiting a different mechanism of action which is not dependent on the LPS composition. The results highlight the correlation between the protein's antimicrobial activity and its ability to interact with the LPS outer layer and promote bacterial agglutination.

Development of a blocking latex agglutination test for the detection of antibodies to chicken anemia virus.

PubMed

Trinh, Dai Quang; Ogawa, Haruko; Bui, Vuong Nghia; Nguyen, Tham Thi Hong; Gronsang, Dulyatad; Baatartsogt, Tugsbaatar; Kizito, Mugimba Kahoza; AboElkhair, Mohammed; Yamaguchi, Shigeo; Nguyen, Viet Khong; Imai, Kunitoshi

2015-09-01

A blocking latex agglutination test (b-LAT) developed in this study was evaluated for the detection of antibodies against chicken anemia virus (CAV) in chickens. Polystyrene latex beads were coupled with a neutralizing monoclonal antibody (mAb) to CAV (mAb-beads). When mAb-beads were mixed with antigens prepared from the lysate of MDCC-MSB1 cells infected with CAV, agglutination occurred. A short pre-incubation of CAV antigens with CAV-specific antiserum inhibited the agglutination of mAb-beads. The test results were obtained within 5min. The specificity of b-LAT was evaluated using sera from specific pathogen-free chickens and sera containing antibodies to avian influenza virus, Newcastle disease virus, infectious bursal disease virus, and Marek's disease virus; nonspecific agglutination and cross-reactivity with antibodies to unrelated viruses were not observed. The examination of 94 serum samples collected from commercial breeder chickens of various ages (17-63 weeks) revealed good agreement (93.6%, Kappa value=0.82) between b-LAT and a virus neutralization test, known to be most sensitive and specific in the detection of antibodies to CAV. These results indicate that b-LAT, a simple and rapid test, is a useful and reliable tool in CAV serology. Copyright © 2015 Elsevier B.V. All rights reserved.

Lack of chemical fractionation in major and minor elements during agglutinate formation. [in lunar soil

NASA Technical Reports Server (NTRS)

Hu, H.-N.; Taylor, L. A.

1977-01-01

Rhodes et al. (1975, 1976) and Adams et al. (1975) have reported that the agglutinate fraction of the soils on the lunar surface displays a marked enrichment in Fe, Mg, Ti, K, and La, and a depletion in Ca, Na, Al, and Eu, relative to the bulk soils. The reported investigation is concerned with a testing of the theory of chemical fractionation involving magnetic separation which was developed in connection with these findings. Soils 64421 and 71501 were sieved and the magnetic fractions separated according to the method developed by Adams and McCord (1973). Analyses of agglutinitic glass did not indicate any appreciable chemical fractionation for the major and minor elements accompanying the agglutination process. It was found that most, if not all fractionations reported can be accounted for completely by the magnetic nonagglutinate impurities in the agglutinate fraction. It is, therefore, concluded that there appears to be no reason to make use of any chemical fractionation theory, whose validity remains to be demonstrated.

Determinants of Erythrocyte Hydration In Current Opinion in Hematology

PubMed Central

Rinehart, Jesse; Gulcicek, Erol E.; Joiner, Clinton H.; Lifton, Richard P.; Gallagher, Patrick G.

2012-01-01

Purpose of Review Maintenance of cellular water and solute homeostasis is critical for survival of the erythrocyte. Inherited or acquired disorders that perturb this homeostasis jeopardize the erythrocyte, leading to its premature destruction. This report reviews recent progress in our understanding the determinants of erythrocyte hydration and its related disorders. Recent Findings The molecular and genetic bases of primary disorders of erythrocyte hydration are poorly understood. Recent studies have implicated roles for the anion transporter, SLC4A1, and the Rh-associated glycoprotein, RhAG. The most common secondary disorder associated with perturbed hydration of the erythrocyte is sickle cell disease, where dehydration contributes to disease pathology and clinical complications. Advances in understanding the mechanisms regulating erythrocyte solute and water content, particularly associated with KCl cotransport and Gardos channel activation, have revealed novel signaling mechanisms controlling erythrocyte hydration. These signaling pathways may provide innovative strategies to prevent erythrocyte dehydration in sickle cell disease. Summary Clinical, translational and biologic studies all contribute to our knowledge of erythrocyte hydration. Understanding the mechanisms controlling erythrocyte water and solute homeostasis will serve as a paradigm for other cells and may reveal new therapeutic targets for disease prevention and treatment. PMID:20182354

Conjugated Bilirubin Triggers Anemia by Inducing Erythrocyte Death

PubMed Central

Lang, Elisabeth; Gatidis, Sergios; Freise, Noemi F; Bock, Hans; Kubitz, Ralf; Lauermann, Christian; Orth, Hans Martin; Klindt, Caroline; Schuier, Maximilian; Keitel, Verena; Reich, Maria; Liu, Guilai; Schmidt, Sebastian; Xu, Haifeng C; Qadri, Syed M; Herebian, Diran; Pandyra, Aleksandra A; Mayatepek, Ertan; Gulbins, Erich; Lang, Florian; Häussinger, Dieter; Lang, Karl S; Föller, Michael; Lang, Philipp A

2015-01-01

Hepatic failure is commonly associated with anemia, which may result from gastrointestinal bleeding, vitamin deficiency, or liver-damaging diseases, such as infection and alcohol intoxication. At least in theory, anemia during hepatic failure may result from accelerated clearance of circulating erythrocytes. Here we show that bile duct ligation (BDL) in mice leads to severe anemia despite increased reticulocyte numbers. Bilirubin stimulated suicidal death of human erythrocytes. Mechanistically, bilirubin triggered rapid Ca2+ influx, sphingomyelinase activation, formation of ceramide, and subsequent translocation of phosphatidylserine to the erythrocyte surface. Consistent with our in vitro and in vivo findings, incubation of erythrocytes in serum from patients with liver disease induced suicidal death of erythrocytes in relation to their plasma bilirubin concentration. Consistently, patients with hyperbilirubinemia had significantly lower erythrocyte and significantly higher reticulocyte counts compared to patients with low bilirubin levels. Conclusion: Bilirubin triggers suicidal erythrocyte death, thus contributing to anemia during liver disease. (Hepatology 2015;61:275–284) PMID:25065608

Python erythrocytes are resistant to α-hemolysin from Escherichia coli.

PubMed

Larsen, Casper K; Skals, Marianne; Wang, Tobias; Cheema, Muhammad U; Leipziger, Jens; Praetorius, Helle A

2011-12-01

α-Hemolysin (HlyA) from Escherichia coli lyses mammalian erythrocytes by creating nonselective cation pores in the membrane. Pore insertion triggers ATP release and subsequent P2X receptor and pannexin channel activation. Blockage of either P2X receptors or pannexin channels reduces HlyA-induced hemolysis. We found that erythrocytes from Python regius and Python molurus are remarkably resistant to HlyA-induced hemolysis compared to human and Trachemys scripta erythrocytes. HlyA concentrations that induced maximal hemolysis of human erythrocytes did not affect python erythrocytes, but increasing the HlyA concentration 40-fold did induce hemolysis. Python erythrocytes were more resistant to osmotic stress than human erythrocytes, but osmotic stress tolerance per se did not confer HlyA resistance. Erythrocytes from T. scripta, which showed higher osmotic resistance than python erythrocytes, were as susceptible to HlyA as human erythrocytes. Therefore, we tested whether python erythrocytes lack the purinergic signalling known to amplify HlyA-induced hemolysis in human erythrocytes. P. regius erythrocytes increased intracellular Ca²⁺ concentration and reduced cell volume when exposed to 3 mM ATP, indicating the presence of a P2X₇-like receptor. In addition, scavenging extracellular ATP or blocking P2 receptors or pannexin channels reduced the HlyA-induced hemolysis. We tested whether the low HlyA sensitivity resulted from low affinity of HlyA to the python erythrocyte membrane. We found comparable incorporation of HlyA into human and python erythrocyte membranes. Taken together, the remarkable HlyA resistance of python erythrocytes was not explained by increased osmotic resistance, lack of purinergic hemolysis amplification, or differences in HlyA affinity.

Trichostatin A (TSA) improves the development of rabbit-rabbit intraspecies cloned embryos, but not rabbit-human interspecies cloned embryos.

PubMed

Shi, Li-Hong; Miao, Yi-Liang; Ouyang, Ying-Chun; Huang, Jun-Cheng; Lei, Zi-Li; Yang, Ji-Wen; Han, Zhi-Ming; Song, Xiang-Fen; Sun, Qing-Yuan; Chen, Da-Yuan

2008-03-01

The interspecies somatic cell nuclear transfer (iSCNT) technique for therapeutic cloning gives great promise for treatment of many human diseases. However, the incomplete nuclear reprogramming and the low blastocyst rate of iSCNT are still big problems. Herein, we observed the effect of TSA on the development of rabbit-rabbit intraspecies and rabbit-human interspecies cloned embryos. After treatment with TSA for 6 hr during activation, we found that the blastocyst rate of rabbit-rabbit cloned embryos was more than two times higher than that of untreated embryos; however, the blastocyst rate of TSA-treated rabbit-human interspecies cloned embryos decreased. We also found evident time-dependent histone deacetylation-reacetylation changes in rabbit-rabbit cloned embryos, but not in rabbit-human cloned embryos from fusion to 6 hr after activation. Our results suggest that TSA-treatment does not improve blastocyst development of rabbit-human iSCNT embryos and that abnormal histone deacetylation-reacetylation changes in iSCNT embryos may account for their poor blastocyst development. (c) 2008 Wiley-Liss, Inc.

Lectin-Like Constituents of Foods Which React with Components of Serum, Saliva, and Streptococcus mutans

PubMed Central

Gibbons, R. J.; Dankers, I.

1981-01-01

Hot and cold aqueous extracts were prepared from 22 commonly ingested fruits, vegetables, and seeds. When tested by agar diffusion, extracts from 13 and 10 of the foods formed precipitin bands with samples of normal rabbit serum and human saliva, respectively; extracts from four of the foods also reacted with antigen extracts of strains of Streptococcus mutans. When added to rabbit antiserum, extracts from 18 of 21 foods tested inhibited reactivity with antigen extracts derived from S. mutans MT3. Extracts from 16 foods agglutinated whole S. mutans cells, whereas those from 10 foods agglutinated human erythrocytes of blood types A and B. The lectin-like activities of extracts which reacted with human saliva were studied further. Pretreatment of saliva-coated hydroxyapatite (S-HA) beads with extracts of bananas, coconuts, carrots, alfalfa, and sunflower seeds markedly reduced the subsequent adsorption of S. mutans MT3. Pretreatment of S-HA with banana extract also strongly inhibited adsorption of S. mutans H12 and S. sanguis C1, but it had little effect on attachment of Actinomyces naeslundii L13 or A. viscosus LY7. Absorption experiments indicated that the component(s) in banana extract responsible for inhibiting streptococcal adsorption to S-HA was identical to that which bound to human erythrocytes. The banana hemagglutinin exhibited highest activity between pH 7 and 8, and it was inhibited by high concentrations of glucosamine, galactosamine, and, to a lesser extent, mannosamine. Other sugars tested had no effect. The selective bacterial adsorption-inhibiting effect noted for banana extract was also observed in studies with purified lectins. Thus, pretreating S-HA with wheat germ agglutinin and concanavalin A inhibited adsorption of S. mutans MT3 cells, whereas peanut agglutinin, Ulex agglutinin, Dolichos agglutinin, and soybean agglutinin had little effect; none of these lectins affected attachment of A. viscosus LY7. Collectively, the observations suggest that

Evidence that forskolin binds to the glucose transporter of human erythrocytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lavis, V.R.; Lee, D.P.; Shenolikar, S.

1987-10-25

Binding of (4-/sup 3/H)cytochalasin B and (12-/sup 3/H)forskolin to human erythrocyte membranes was measured by a centrifugation method. Glucose-displaceable binding of cytochalasin B was saturable, with KD = 0.11 microM, and maximum binding approximately 550 pmol/mg of protein. Forskolin inhibited the glucose-displaceable binding of cytochalasin B in an apparently competitive manner, with K1 = 3 microM. Glucose-displaceable binding of (12-/sup 3/H)forskolin was also saturable, with KD = 2.6 microM and maximum binding approximately equal to 400 pmol/mg of protein. The following compounds inhibited binding of (12-/sup 3/H)forskolin and (4-/sup 3/H)cytochalasin B equivalently, with relative potencies parallel to their reported affinitiesmore » for the glucose transport system: cytochalasins A and D, dihydrocytochalasin B, L-rhamnose, L-glucose, D-galactose, D-mannose, D-glucose, 2-deoxy-D-glucose, 3-O-methyl-D-glucose, phloretin, and phlorizin. A water-soluble derivative of forskolin, 7-hemisuccinyl-7-desacetylforskolin, displaced equivalent amounts of (4-/sup 3/H)cytochalasin B or (12-/sup 3/H)forskolin. Rabbit erythrocyte membranes, which are deficient in glucose transporter, did not bind either (4-/sup 3/H)cytochalasin B or (12-/sup 3/H)forskolin in a glucose-displaceable manner. These results indicate that forskolin, in concentrations routinely employed for stimulation of adenylate cyclase, binds to the glucose transporter. Endogenous ligands with similar specificities could be important modulators of cellular metabolism.« less

Studies on chemical modification of cold agglutinin from the snail Achatina fulica.

PubMed Central

Sarkar, M; Mitra, D; Sen, A K

1987-01-01

The cold agglutinin isolated from the albumin gland of the snail Achatina fulica was modified with various chemical reagents in order to detect the amino acids and/or carbohydrate residues present in its carbohydrate-binding sites. Treatment with reagents considered specific for modification of lysine, arginine and tryptophan residues of the cold agglutinin did not affect the carbohydrate-binding activity of the agglutinin. Modification of tyrosine residues showed some change. However, modification with carbodiimide followed by alpha-aminobutyric acid methyl ester causes almost complete loss of its binding activity, indicating the involvement of aspartic acid and glutamic acid in its carbohydrate-binding activity. The carbohydrate residues of the cold agglutinin were removed by beta-elimination reaction, indicating that the sugars are O-glycosidically linked to protein part of the molecule. Removal of galactose residues from the cold agglutinin by the action of beta-galactosidase indicated that the galactose molecules are beta-linked. These carbohydrate-modified glycoproteins showed a marked change in agglutination property, i.e. they agglutinated rabbit erythrocytes at both 10 degrees C and 25 degrees C, indicating that the galactose residues of the glycoprotein play an important role in the cold-agglutination property of the glycoprotein. The c.d. data showed the presence of an almost identical type of random-coil conformation in the native cold agglutinin at 10 degrees C and in the carbohydrate-modified glycoprotein at 10 degrees C and 25 degrees C. This particular random-coil conformation is essential for carbohydrate-binding property of the agglutinin. Images Fig. 1. PMID:3118867

A critical role for the regulation of Syk from agglutination to aggregation in human platelets.

PubMed

Shih, Chun-Ho; Chiang, Tin-Bin; Wang, Wen-Jeng

2014-01-10

Agglucetin, a tetrameric glycoprotein (GP) Ibα agonist from Formosan Agkistrodon acutus venom, has been characterized as an agglutination inducer in human washed platelets (WPs). In platelet-rich plasma (PRP), agglucetin dramatically elicits a biphasic response of agglutination and subsequent aggregation. For clarifying the intracellular signaling events from agglutination to aggregation in human platelets, we examined the essential signaling molecules involved through the detection of protein tyrosine phosphorylation (PTP). In WPs, an anti-GPIbα monoclonal antibody (mAb) AP1, but not a Src kinase inhibitor PP1, completely inhibited agglucetin-induced agglutination. However, PP1 but not AP1 had a potent suppression on platelet aggregation by a GPVI activator convulxin. The PTP analyses showed agglucetin alone can cause a weak pattern involving sequential phosphorylation of Lyn/Fyn, Syk, SLP-76 and phospholipase Cγ2 (PLCγ2). Furthermore, a Syk-selective kinase inhibitor, piceatannol, significantly suppressed the aggregating response in agglucetin-activated PRP. Analyzed by flow cytometry, the binding capacity of fluorophore-conjugated PAC-1, a mAb recognizing activated integrin αIIbβ3, was shown to increase in agglucetin-stimulated platelets. Again, piceatannol but not PP1 had a concentration-dependent suppression on agglucetin-induced αIIbβ3 exposure. Moreover, the formation of signalosome, including Syk, SLP-76, VAV, adhesion and degranulation promoting adapter protein (ADAP) and PLCγ2, are required for platelet aggregation in agglucetin/fibrinogen-activated platelets. In addition, GPIbα-ligation via agglucetin can substantially promote the interactions between αIIbβ3 and fibrinogen. Therefore, the signal pathway of Lyn/Fyn/Syk/SLP-76/ADAP/VAV/PLCγ2/PKC is sufficient to trigger platelet aggregation in agglucetin/fibrinogen-pretreated platelets. Importantly, Syk may function as a major regulator for the response from GPIbα-initiated agglutination to

The role of RhD agglutination for the detection of weak D red cells by anti-D flow cytometry.

PubMed

Grey, D E; Davies, J I; Connolly, M; Fong, E A; Erber, W N

2005-04-01

Anti-D flow cytometry is an accurate method for quantifying feto-maternal haemorrhage (FMH). However, weak D red cells with <1000 RhD sites are not detectable using this methodology but are immunogenic. As quantitation of RhD sites is not practical, an alternative approach is required to identify those weak D fetal red cells where anti-D flow cytometry is inappropriate. We describe a simple algorithm based on RhD agglutination and flow cytometry peak separation. All weak D (n = 34) gave weak agglutination with RUM-1 on immediate spin (grading agglutination (grading 3) was observed and the red cells were undetectable by flow cytometry. In the second subgroup, agglutination was strong (grading 4) and the red cells were detectable by anti-D flow cytometry. The accuracy of the quantitation was dependent on adequate separation of the weak D and RhD-negative peaks as in seven of 11 samples <1.11% of an expected 2% red cells were detectable. Monitoring RhD agglutination and flow cytometric peak separation are pivotal if anti-D flow cytometry is to be maintained as the primary technique for FMH quantitation in the routine laboratory.

[Kinetics of Cu crossing human erythrocyte membrane].

PubMed

Dun, Zhu Ci Ren

2014-12-01

This study was aimed to investigate various factors influencing the proceduction of Cu(II) crossing human erythrocyte membrane, including concentration of Cu²⁺, pH value of the medium, temperature and time of incubation, and to derive kinetic equation of Cu(II) crossing human erythrocyte membrane. Suspension red blood cells were incubated by Cu²⁺, then content of Cu²⁺ crossed human erythrocyte membrane was determined by atomic absorption spectrometry under various conditions after digestion. The results showed that content of Cu²⁺ crossed human erythrocyte membrane increased with the increase of extracellular Cu²⁺ and enhancement of incubation temperature, and the content of Cu²⁺ crossed human erythrocyte membrane showed a increasing tendency when pH reached to 6.2-7.4, and to maximum at pH 7.4, then gradually decreased at range of pH 7.4-9.2. It is concluded that the Cu²⁺ crossing human erythrocyte has been confirmed to be the first order kinetics characteristics within 120 min, and the linear equation is 10³ × Y = 0.0497t +6.5992.

Stimulation of erythrocyte death by phloretin.

PubMed

Bissinger, Rosi; Fischer, Salome; Jilani, Kashif; Lang, Florian

2014-01-01

Phloretin, a natural component of apples, pears and strawberries, has previously been shown to stimulate apoptosis of nucleated cells. Erythrocytes may similarly enter suicidal death or eryptosis, which is characterized by cell shrinkage and phospholipid scrambling of the erythrocyte cell membrane with phosphatidylserine translocation to the erythrocyte surface. Stimulators of eryptosis include increase of cytosolic Ca(2+)-activity ([Ca(2+)]i), ceramide, ATP depletion, and activation of protein kinase C (PKC) as well as p38 mitogen activated protein kinase (p38 kinase). Phosphatidylserine exposure at the cell surface was estimated from annexin V binding, cell volume from forward scatter, [Ca(2+)]i from Fluo3-fluorescence, and ceramide abundance from binding of specific antibodies. A 48 h exposure of human erythrocytes to phloretin significantly increased the percentage of annexin-V-binding cells (≥100 µM) without significantly influencing forward scatter. Phloretin did not significantly modify [Ca(2+)]i and the stimulation of annexin-V-binding by phloretin (300 µM) did not require presence of extracellular Ca(2+). Phloretin did not significantly modify erythrocyte ATP levels, and the effect of phloretin on annexin-V-binding was not significantly altered by PKC inhibitor staurosporine (1 µM) or p38 kinase inhibitor SB2203580 (2 µM). However, phloretin significantly increased the ceramide abundance at the cell surface. Phloretin stimulates phospholipid scrambling of the erythrocyte cell membrane, an effect at least partially due to up-regulation of ceramide abundance.

The Classroom-Friendly ABO Blood Types Kit: Blood Agglutination Simulation

ERIC Educational Resources Information Center

Arnold, Savittree Rochanasmita; Kruatong, Tussatrin; Dahsah, Chanyah; Suwanjinda, Duongdearn

2012-01-01

The classroom-friendly ABO blood type kit was developed by combining advantages of modelling and a simulation laboratory to teach the topics of ABO blood types and blood transfusion. Teachers can easily simulate the agglutination reaction on a blood type testing plate in the classroom, and show the students how this reaction occurs by using the…

Studying red blood cell agglutination by measuring membrane viscosity with optical tweezers

NASA Astrophysics Data System (ADS)

Fernandes, Heloise P.; Fontes, Adriana; de Thomaz, André A.; Barbosa, Luiz C.; Barjas-Castro, Maria L.; Cesar, Carlos L.

2007-09-01

The red blood cell (RBC) viscoelastic membrane contains proteins and glycoproteins embedded in a fluid lipid bilayer that are responsible for cell agglutination. Manipulating RBCs rouleaux with a double optical tweezers, we observed that the cells slide easily one over the others but are strongly connected by their edges. An explanation for this behavior could be the fact that when the cells slide one over the others, proteins are dragged through the membrane. It confers to the movement a viscous characteristic that is dependent of the velocity between the RBCs and justifies why is so easy to slide them apart. Therefore, in a first step of this work, by measuring the force as a function of the relative velocity between two cells, we confirmed this assumption and used this viscous characteristic of the RBC rouleaux to determine the apparent membrane viscosity of the cell. As this behavior is related to the proteins interactions, we can use the apparent membrane viscosity to obtain a better understanding about cell agglutination. Methods related to cell agglutination induced by antigen-antibody interactions are the basis of most of tests used in transfusion centers. Then, in a second step of this work, we measured the apparent membrane viscosity using antibodies. We observed that this methodology is sensitive to different kinds of bindings between RBCs. Better comprehension of the forces and bindings between RBCs could improve the sensibility and specificity of the hemagglutination reactions and also guides the development of new potentiator substances.

Comparison of agglutinating and neutralizing antibodies to serovar hardjo in sows immunized with two commercial whole culture polivalent anti-leptospira bacterins

PubMed Central

Soto, Francisco Rafael Martins; Pinheiro, Sônia Regina; Morais, Zenaide Maria; Gonçales, Amane Paldês; de Azevedo, Sérgio Santos; Bernardi, Fernanda; Camargo, Sebastião Rodrigues; Vasconcellos, Silvio Arruda

2008-01-01

It was performed the comparison of the intensity and duration of agglutinating and neutralizing antibodies to serovar Hardjo in swines vaccinated with two commercial anti-leptospira bacterins. Sows no reactive to 24 Leptospira sp serovars in the microscopic agglutination test (MAT) were divided in three groups: Group A (n=08): received two vaccine A doses with 30 days interval, Group B (n=08) two vaccine B doses with 30 days interval and Group C (n=08): control no vaccinated against leptospirosis.Blood samples were collected each 30 days during six months following the first vaccination. The sera were tested by MAT and growth inhibition test (GIT) to serovar Hardjo in order to evaluate respectively agglutinating and neutralizing antibodies. It was found that neutralizing antibodies persisted for a longer time than the agglutinating ones and that the absence of agglutinating antibodies does not means in the absence of the neutralizing. The peaks of agglutinating antibodies was obtained at least 30 days earlier than that produced by neutralizing. The duration of both kinds of antibodies measured differed between the two bacterines tested. The period for inducing neutralizing antibodies against serovar Hardjo indicated that gilts must be immunized with two doses of whole culture anti-leptospira bacterines applied 30 days each other at least 90 days before the first mating. For the maintenance of hight levels of neutralizing antibodies the revaccinations must be performed every six months after the first vaccination. PMID:24031250

The malaria parasite RhopH protein complex interacts with erythrocyte calmyrin identified from a comprehensive erythrocyte protein library.

PubMed

Miura, Toyokazu; Takeo, Satoru; Ntege, Edward H; Otsuki, Hitoshi; Sawasaki, Tatsuya; Ishino, Tomoko; Takashima, Eizo; Tsuboi, Takafumi

2018-06-02

Malaria merozoite apical organelles; microneme and rhoptry secreted proteins play functional roles during and following invasion of host erythrocytes. Among numerous proteins, the rhoptries discharge high molecular weight proteins known as RhopH complex. Recent reports suggest that the RhopH complex is essential for growth and survival of the malaria parasite within erythrocytes. However, an in-depth understanding of the host-parasite molecular interactions is indispensable. Here we utilized a comprehensive mouse erythrocyte protein library consisting of 443 proteins produced by a wheat germ cell-free system, combined with AlphaScreen technology to identify mouse erythrocyte calmyrin as an interacting molecule of the rodent malaria parasite Plasmodium yoelii RhopH complex (PyRhopH). The PyRhopH interaction was dependent on the calmyrin N-terminus and divalent cation capacity. The finding unveils a recommendable and invaluable usefulness of our comprehensive mouse erythrocyte protein library together with the AlphaScreen technology in investigating a wide-range of host-parasite molecular interactions. Copyright © 2018 Elsevier Inc. All rights reserved.

Patterns of purine nucleotides in fish erythrocytes.

PubMed

Leray, C

1979-01-01

1. The purine nucleotides were determined in the whole blood of 9 fresh water teleosts and 2 marine selachians. 2. GTP and ATP accounted for 88-99% of the total erythrocytes purines. 3. The ATP/ADP ratio ranged from 11 to 60 in the erythrocytes of the fish examined. 4. GTP is widely distributed in fish erythrocytes but its level ranged from 1 to 33 nmol/mg Hb (0.4 to 9 mumol/ml erythrocyte). 5. Lepomis and Esox exhibited a GTP/ATP ratio as elevated as in Anguilla; moreover the concentration of GTP per mol of Hb (physiologically most indicative) is higher in Lepomis, Esox, Ictalurus and Silurus than in Anguilla.

Mechanisms of Human Erythrocytic Bioactivation of Nitrite*

PubMed Central

Liu, Chen; Wajih, Nadeem; Liu, Xiaohua; Basu, Swati; Janes, John; Marvel, Madison; Keggi, Christian; Helms, Christine C.; Lee, Amber N.; Belanger, Andrea M.; Diz, Debra I.; Laurienti, Paul J.; Caudell, David L.; Wang, Jun; Gladwin, Mark T.; Kim-Shapiro, Daniel B.

2015-01-01

Nitrite signaling likely occurs through its reduction to nitric oxide (NO). Several reports support a role of erythrocytes and hemoglobin in nitrite reduction, but this remains controversial, and alternative reductive pathways have been proposed. In this work we determined whether the primary human erythrocytic nitrite reductase is hemoglobin as opposed to other erythrocytic proteins that have been suggested to be the major source of nitrite reduction. We employed several different assays to determine NO production from nitrite in erythrocytes including electron paramagnetic resonance detection of nitrosyl hemoglobin, chemiluminescent detection of NO, and inhibition of platelet activation and aggregation. Our studies show that NO is formed by red blood cells and inhibits platelet activation. Nitric oxide formation and signaling can be recapitulated with isolated deoxyhemoglobin. Importantly, there is limited NO production from erythrocytic xanthine oxidoreductase and nitric-oxide synthase. Under certain conditions we find dorzolamide (an inhibitor of carbonic anhydrase) results in diminished nitrite bioactivation, but the role of carbonic anhydrase is abrogated when physiological concentrations of CO2 are present. Importantly, carbon monoxide, which inhibits hemoglobin function as a nitrite reductase, abolishes nitrite bioactivation. Overall our data suggest that deoxyhemoglobin is the primary erythrocytic nitrite reductase operating under physiological conditions and accounts for nitrite-mediated NO signaling in blood. PMID:25471374

Characterization of carrier erythrocytes for biosensing applications

NASA Astrophysics Data System (ADS)

Bustamante López, Sandra C.; Meissner, Kenith E.

2017-09-01

Erythrocyte abundance, mobility, and carrying capacity make them attractive as a platform for blood analyte sensing as well as for drug delivery. Sensor-loaded erythrocytes, dubbed erythrosensors, could be reinfused into the bloodstream, excited noninvasively through the skin, and used to provide measurement of analyte levels in the bloodstream. Several techniques to load erythrocytes, thus creating carrier erythrocytes, exist. However, their cellular characteristics remain largely unstudied. Changes in cellular characteristics lead to removal from the bloodstream. We hypothesize that erythrosensors need to maintain native erythrocytes' (NEs) characteristics to serve as a long-term sensing platform. Here, we investigate two loading techniques and the properties of the resulting erythrosensors. For loading, hypotonic dilution requires a hypotonic solution while electroporation relies on electrical pulses to perforate the erythrocyte membrane. We analyze the resulting erythrosensor signal, size, morphology, and hemoglobin content. Although the resulting erythrosensors exhibit morphological changes, their size was comparable with NEs. The hypotonic dilution technique was found to load erythrosensors much more efficiently than electroporation, and the sensors were loaded throughout the volume of the erythrosensors. Finally, both techniques resulted in significant loss of hemoglobin. This study points to the need for continued development of loading techniques that better preserve NE characteristics.

The calcium content of human erythrocytes

PubMed Central

Harrison, D. G.; Long, C.

1968-01-01

1. The calcium content of human erythrocytes, after removal of the buffy coat and washing free from plasma with isotonic sodium chloride, has been determined by atomic absorption spectrophotometry. The mean value found for normal subjects was 0·634 μg/ml. of packed erythrocytes (0·0158 μg-atom/ml.). The corresponding values for magnesium and zinc were 79·7 and 20·1 μg/ml., respectively. 2. The calcium is considered to be mostly and perhaps exclusively located in the erythrocyte membrane, since, after osmotic haemolysis, the same amount was found in the ghost cells as was present in the erythrocytes from which they were prepared. By contrast, magnesium and zinc, which are essentially intracellular, were lost to the extent of about 96 and 92%, respectively. 3. About 90% of the calcium was removed from erythrocytes by washing with isotonic sodium chloride containing 5 mM ethylenediaminetetraacetate (EDTA), or other complexing agents of high stability constant for calcium. A small fraction of the magnesium but none of the zinc was removed by this treatment. 4. Other complexing agents of lower stability constant removed somewhat less calcium from the erythrocytes. Citrate was totally ineffective. 5. The buffy coat had a high calcium content, but this could not be removed by washing with EDTA. 6. Calcium was also determined in trichloroacetic acid extracts of ghost cells after ashing and treatment with bis-(o-hydroxyphenylimino)-ethane and measuring the red complex spectrophotometrically. The values obtained confirmed the atomic absorption measurements. PMID:4972779

Metabolism of acetylcholine in human erythrocytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chapman, E.S.

1990-01-01

In order to examine the possible role of erythrocyte acetylcholinesterase in the maintenance of membrane phospholipid content and membrane fluidity, experiments were performed to monitor the activity of the enzyme and follow the fate of one of its hydrolytic products, choline. Intact human erythrocytes were incubated with acetylcholine (choline methyl-{sup 14}C). The incubation resulted in the hydrolysis of acetylcholine to acetate and choline; the reaction was catalyzed by membrane acetylcholinesterase. The studies demonstrate the further metabolism of choline. Experiments were carried out to determine rate of hydrolysis of acetylcholine, uptake of choline, identification of intracellular metabolites of choline, and identificationmore » of radiolabeled membrane components. Erythrocytes at a 25% hematocrit were incubated in an isoosmotic bicarbonate buffer pH 7.4, containing glucose, adenosine, streptomycin and penicillin with 0.3 {mu}Ci of acetylcholine (choline methyl-{sup 14}C), for 24 hours. Aliquots of the erythrocyte suspension were taken throughout for analysis. Erythrocytes were washed free of excess substrate, lysed, and the hemolysate was extracted for choline and its metabolites. Blank samples containing incubation buffer and radiolabeled acetylcholine only, and erythrocyte hemolysate extracts were analyzed for choline content, the difference between blank samples and hemolysate extracts was the amount of choline originating from acetylcholine and attributable to acetylcholinesterase activity. The conversion of choline to {sup 14}C-betaine is noted after several minutes of incubation; at 30 minutes, more than 80% of {sup 14}C-choline is taken up and after several hours, detectable levels of radiolabeled S-adenosylmethionine were present in the hemolysate extract.« less

Disposable rabbit

DOEpatents

Lewis, Leroy C.; Trammell, David R.

1986-01-01

A disposable rabbit for transferring radioactive samples in a pneumatic transfer system comprises aerated plastic shaped in such a manner as to hold a radioactive sample and aerated such that dissolution of the rabbit in a solvent followed by evaporation of the solid yields solid waste material having a volume significantly smaller than the original volume of the rabbit.

Disposal rabbit

DOEpatents

Lewis, L.C.; Trammell, D.R.

1983-10-12

A disposable rabbit for transferring radioactive samples in a pneumatic transfer system comprises aerated plastic shaped in such a manner as to hold a radioactive sample and aerated such that dissolution of the rabbit in a solvent followed by evaporation of the solid yields solid waste material having a volume significantly smaller than the original volume of the rabbit.

Calpain-1 knockout reveals broad effects on erythrocyte deformability and physiology

PubMed Central

Wieschhaus, Adam; Khan, Anwar; Zaidi, Asma; Rogalin, Henry; Hanada, Toshihiko; Liu, Fei; De Franceschi, Lucia; Brugnara, Carlo; Rivera, Alicia; Chishti, Athar H.

2014-01-01

Pharmacological inhibitors of cysteine proteases have provided useful insights into the regulation of calpain activity in erythrocytes. However, the precise biological function of calpain activity in erythrocytes remains poorly understood. Erythrocytes express calpain-1, an isoform regulated by calpastatin, the endogenous inhibitor of calpains. In the present study, we investigated the function of calpain-1 in mature erythrocytes using our calpain-1-null [KO (knockout)] mouse model. The calpain-1 gene deletion results in improved erythrocyte deformability without any measurable effect on erythrocyte lifespan in vivo. The calcium-induced sphero-echinocyte shape transition is compromised in the KO erythrocytes. Erythrocyte membrane proteins ankyrin, band 3, protein 4.1R, adducin and dematin are degraded in the calcium-loaded normal erythrocytes but not in the KO erythrocytes. In contrast, the integrity of spectrin and its state of phosphorylation are not affected in the calcium-loaded erythrocytes of either genotype. To assess the functional consequences of attenuated cytoskeletal remodelling in the KO erythrocytes, the activity of major membrane transporters was measured. The activity of the K+–Cl− co-transporter and the Gardos channel was significantly reduced in the KO erythrocytes. Similarly, the basal activity of the calcium pump was reduced in the absence of calmodulin in the KO erythrocyte membrane. Interestingly, the calmodulin-stimulated calcium pump activity was significantly elevated in the KO erythrocytes, implying a wider range of pump regulation by calcium and calmodulin. Taken together, and with the atomic force microscopy of the skeletal network, the results of the present study provide the first evidence for the physiological function of calpain-1 in erythrocytes with therapeutic implications for calcium imbalance pathologies such as sickle cell disease. PMID:22870887

Calpain-1 knockout reveals broad effects on erythrocyte deformability and physiology.

PubMed

Wieschhaus, Adam; Khan, Anwar; Zaidi, Asma; Rogalin, Henry; Hanada, Toshihiko; Liu, Fei; De Franceschi, Lucia; Brugnara, Carlo; Rivera, Alicia; Chishti, Athar H

2012-11-15

Pharmacological inhibitors of cysteine proteases have provided useful insights into the regulation of calpain activity in erythrocytes. However, the precise biological function of calpain activity in erythrocytes remains poorly understood. Erythrocytes express calpain-1, an isoform regulated by calpastatin, the endogenous inhibitor of calpains. In the present study, we investigated the function of calpain-1 in mature erythrocytes using our calpain-1-null [KO (knockout)] mouse model. The calpain-1 gene deletion results in improved erythrocyte deformability without any measurable effect on erythrocyte lifespan in vivo. The calcium-induced sphero-echinocyte shape transition is compromised in the KO erythrocytes. Erythrocyte membrane proteins ankyrin, band 3, protein 4.1R, adducin and dematin are degraded in the calcium-loaded normal erythrocytes but not in the KO erythrocytes. In contrast, the integrity of spectrin and its state of phosphorylation are not affected in the calcium-loaded erythrocytes of either genotype. To assess the functional consequences of attenuated cytoskeletal remodelling in the KO erythrocytes, the activity of major membrane transporters was measured. The activity of the K+-Cl- co-transporter and the Gardos channel was significantly reduced in the KO erythrocytes. Similarly, the basal activity of the calcium pump was reduced in the absence of calmodulin in the KO erythrocyte membrane. Interestingly, the calmodulin-stimulated calcium pump activity was significantly elevated in the KO erythrocytes, implying a wider range of pump regulation by calcium and calmodulin. Taken together, and with the atomic force microscopy of the skeletal network, the results of the present study provide the first evidence for the physiological function of calpain-1 in erythrocytes with therapeutic implications for calcium imbalance pathologies such as sickle cell disease.

Potassium transport in monkey erythrocytes.

PubMed

Stewart, G W; Blackstock, E J; Hall, A C; Ellory, J C

1989-01-01

K transport in Rhesus and Cynomolgus monkey erythrocytes has been characterised and compared to that in human erythrocytes. Transport due to the NaK pump, residual (diffusional) leak, volume-, pressure- and N-ethyl-maleimide-stimulated KCl system and internal Ca2+-stimulated K channel were similar to that in man but in the monkey it differed, in lacking the loop-diuretic-sensitive NaKCl cotransport system.

Automated point-of-care testing for ABO agglutination test: proof of concept and validation.

PubMed

El Kenz, H; Corazza, F

2015-07-01

ABO-incompatible red blood cell transfusions still represent an important hazard in transfusion medicine. Therefore, some countries have introduced a systematic bedside ABO agglutination test checking that the right blood is given to the right patient. However, this strategy requires an extremely time-consuming learning programme and relies on a subjective interpretation of ABO test cards agglutination. We developed a prototype of a fully automated device performing the bedside agglutination test that could be completed by reading of a barcoded wristband. This POCT checks the ABO compatibility between the patient and the blood bag. Proof of concept and analytical validation of the prototype has been completed on 451 blood samples: 238 donor packed red blood cells, 137 consecutive unselected patients for whom a blood group determination had been ordered and on 76 patient samples selected with pathology that could possibly interfere with or impair performances of the assay. We observed 100% concordance for ABO blood groups between the POCT and the laboratory instrument. These preliminary results demonstrate the feasibility of ABO determination with a simple POCT device eliminating manipulation and subjective interpretation responsible for transfusion errors. This device should be linked to the blood bank system allowing all cross-check of the results. © 2015 International Society of Blood Transfusion.

Platelet-independent adhesion of calcium-loaded erythrocytes to von Willebrand factor

PubMed Central

Bierings, Ruben; Meems, Henriet; Mul, Frederik P. J.; Geerts, Dirk; Vlaar, Alexander P. J.; Voorberg, Jan; Hordijk, Peter L.

2017-01-01

Adhesion of erythrocytes to endothelial cells lining the vascular wall can cause vaso-occlusive events that impair blood flow which in turn may result in ischemia and tissue damage. Adhesion of erythrocytes to vascular endothelial cells has been described in multiple hemolytic disorders, especially in sickle cell disease, but the adhesion of normal erythrocytes to endothelial cells has hardly been described. It was shown that calcium-loaded erythrocytes can adhere to endothelial cells. Because sickle erythrocyte adhesion to ECs can be enhanced by ultra-large von Willebrand factor multimers, we investigated whether calcium loading of erythrocytes could promote binding to endothelial cells via ultra-large von Willebrand factor multimers. We used (immunofluorescent) live-cell imaging of washed erythrocytes perfused over primary endothelial cells at venular flow rate. Using this approach, we show that calcium-loaded erythrocytes strongly adhere to histamine-stimulated primary human endothelial cells. This adhesion is mediated by ultra-large von Willebrand factor multimers. Von Willebrand factor knockdown or ADAMTS13 cleavage abolished the binding of erythrocytes to activated endothelial cells under flow. Platelet depletion did not interfere with erythrocyte binding to von Willebrand factor. Our results reveal platelet-independent adhesion of calcium-loaded erythrocytes to endothelium-derived von Willebrand factor. Erythrocyte adhesion to von Willebrand factor may be particularly relevant for venous thrombosis, which is characterized by the formation of erythrocyte-rich thrombi. PMID:28249049

Antibodies to Coprococcus comes in sera of patients with Crohn's disease. Isolation and purification of the agglutinating antigen tested with an ELISA technique.

PubMed

Hazenberg, M P; van de Merwe, J P; Peña, A S; Pennock-Schröder, A M; van Lieshout, L M

1987-07-01

Previous studies showed that agglutinating antibodies to Coprococcus comes, an anaerobic Gram-positive coccoid rod isolated from the faecal flora of patients with Crohn's disease, are more frequently found in sera of Crohn patients than in ulcerative colitis patients and healthy subjects. Isolation of the antigen may be useful in developing a more sensitive and specific diagnostic test. The present study describes first a method to improve the presentation of the relevant agglutinating antigen by the bacterium and second, the purification by column chromatography of a relatively crude antigen extract of C. comes described previously by Hazenberg et al. (1). Comparative results with the agglutination reactions and ELISA technique of extensive series of patients with Crohn's disease and healthy subjects have shown that the agglutinating antigen of C. comes has been isolated. Although the present ELISA technique cannot replace the simple and reliable agglutination reaction for screening purposes, the purified antigen will allow further immunological studies and it is to be hoped that a deeper insight into pathogenesis of the disease will be gained.

From rabbit antibody repertoires to rabbit monoclonal antibodies.

PubMed

Weber, Justus; Peng, Haiyong; Rader, Christoph

2017-03-24

In this review, we explain why and how rabbit monoclonal antibodies have become outstanding reagents for laboratory research and increasingly for diagnostic and therapeutic applications. Starting with the unique ontogeny of rabbit B cells that affords highly distinctive antibody repertoires rich in in vivo pruned binders of high diversity, affinity and specificity, we describe the generation of rabbit monoclonal antibodies by hybridoma technology, phage display and alternative methods, along with an account of successful humanization strategies.

Innate Immunity in Lobsters: Partial Purification and Characterization of a Panulirus cygnus Anti-A Lectin.

PubMed

Flower, Robert L P

2012-01-01

A lectin detected in haemolymph from the Australian spiny lobster Panulirus cygnus agglutinated human ABO Group A cells to a higher titre than Group O or B. The lectin also agglutinated rat and sheep erythrocytes, with reactivity with rat erythrocytes strongly enhanced by treatment with the proteolytic enzyme papain, an observation consistent with reactivity via a glycolipid. The lectin, purified by affinity chromatography on fixed rat-erythrocyte stroma, was inhibited equally by N-acetylglucosamine and N-acetylgalactosamine. Comparison of data from gel filtration of haemolymph (behaving as a 1,800,000 Da macromolecule), and polyacrylamide gel electrophoresis of purified lectin (a single 67,000 Da band), suggested that in haemolymph the lecin was a multimer. The purified anti-A lectin autoprecipitated unless the storage solution contained chaotropic inhibitors (125 mmol/L sucrose: 500 mmol/L urea). The properties of this anti-A lectin and other similar lectins are consistent with a role in innate immunity in these invertebrates.

Response of the rat erythrocyte to ozone exposure

NASA Technical Reports Server (NTRS)

Larkin, E. C.; Kimzey, S. L.; Siler, K.

1978-01-01

Sprague-Dawley rats were exposed to high (6-8 ppm) and moderate (1.5 ppm) amounts of ozone (O3) for various time periods. Response of the rat erythrocyte to ozone was monitored with red blood cell potassium (rubidium) influx studies, with storage stress combined with ultrastructural studies and with levels of erythrocyte glutathione peroxidase and superoxide dismutase. Erythrocytes of rats exposed to O3 showed no significant changes either in their potassium influx or in their glutathione peroxidase and superoxide dismutase activities compared to controls. Erythrocyte differential counts on O3-exposed animals showed significant changes initially as well as following storage stress compared to controls. Rats exposed to 8 ppm O3 for 4 h showed a marked increase in echinocytes. These consistent transformations from discocytes to echinocytes following O3 exposure suggest latent erythrocyte damage has occurred.

A critical review of published methods for analysis of red cell antigen-antibody reactions by flow cytometry, and approaches for resolving problems with red cell agglutination.

PubMed

Arndt, Patricia A; Garratty, George

2010-07-01

Flow cytometry operators often apply familiar white blood cell (WBC) methods when studying red blood cell (RBC) antigens and antibodies. Some WBC methods are not appropriate for RBCs, as the analysis of RBCs requires special considerations, for example, avoidance of agglutination. One hundred seventy-six published articles from 88 groups studying RBC interactions were reviewed. Three fourths of groups used at least one unnecessary WBC procedure for RBCs, and about one fourth did not use any method to prevent/disperse RBC agglutination. Flow cytometric studies were performed to determine the effect of RBC agglutination on results and compare different methods of preventing and/or dispersing agglutination. The presence of RBC agglutinates have been shown to be affected by the type of pipette tip used for mixing RBC suspensions, the number of antigen sites/RBC, the type and concentration of primary antibody, and the type of secondary antibody. For quantitation methods, for example, fetal maternal hemorrhage, the presence of agglutinates have been shown to adversely affect results (fewer fetal D+ RBCs detected). Copyright 2010 Elsevier Inc. All rights reserved.

Rabbit analgesia.

PubMed

Barter, Linda S

2011-01-01

With the increasing popularity of rabbits as household pets, the complexity of diagnostic and surgical procedures performed on rabbits is increasing, along with the frequency of routine surgical procedures. More practitioners are faced with the need to provide adequate analgesia for this species. Preemptive analgesia prior to planned surgical interventions may reduce nervous system changes in response to noxious input, as well as reduce postoperative pain levels and analgesic drug requirements. Concurrent administration of analgesic drugs to anesthetized rabbits undergoing painful procedures is warranted both pre- and intraoperatively as well as postoperatively. This article discusses the neuropharmacologic and pharmacologic aspects of pain in rabbits, and reviews current protocols for the use of analgesic drugs. Published by Elsevier Inc.

The specificity of the cross-reacting antibodies in blood group O sera which produce mixed agglutination

PubMed Central

Franks, D.; Liske, Rosemary

1968-01-01

γM cross-reacting antibodies in group O sera produce mixed agglutination with secretor buccal cells, but not with non-secretor cells. The mixed agglutination with sera which also contain immune anti-B is produced only with A buccal cells and B indicator red cells, and not with B buccal cells, and is inhibited by B secretor saliva or galactose, but not by A secretor saliva. Mixed agglutination with sera containing immune anti-A is produced only with B buccal cells and A indicator red cells, and is inhibited by A secretor saliva or 2-acetamido-2-deoxygalactose (N-acetyl-D-galactosamine), but not by B secretor saliva. If two sera, one containing immune anti-A and the other containing immune anti-B, are mixed together in equal volumes, mixed agglutination is no longer produced with either A buccal cells (and B indicator red cells) or B buccal cells (and A indicator red cells). These observations are thought to be most readily explicable by the hypothesis that the combining site on the cross-reacting antibody is smaller than on specific anti-A or anti-B, and that it reacts with that part of the antigenic determinant which is common to both A and B antigens. As a consequence of the restricted size of the combining site, it is suggested that cross-reacting antibody will have a lower affinity for A or B antigens than specific anti-A or anti-B does, and competes unsuccessfully with specific anti-A or anti-B for combination with antigen on buccal cells. PMID:5638582

[Morphological characteristic of erythrocytes in experimental hypervitaminosis A].

PubMed

Minashkina, T A

2011-01-01

This investigation was aimed at the analysis of the shape and morpho-densitometric parameters of the erythrocytes in rats with experimental hypervitaminosis A. Male Wistar rats received 0.64 mg/g (1167 IU/g) of retinol palmitate (RP) in oil solution orally for 11 consecutive days. Rats fed oil alone and intact animals were used as control groups. At days 5 and 6 of the experiment, the first manifestations of hypervitaminosis A were observed (body mass loss, localized erythema and hemorrhages). In contrast to control groups, in rats with hypervitaminosis A, the area of erythrocyte cytoplasm decreased gradually in response to RP administration. Discocyte/spherocyte/stomatocyte ratio also changed dynamically: the proportion of discocytes progressively decreased, while the amount of spherocytes and stomatocytes increased. These results show that excess of the vitamin A alters the erythrocyte membrane structure. Integral optical density of erythrocyte cytoplasm in RP-treated rats as well as in oil-fed rats was lower than in intact animals. This may be an indirect evidence of the fall in erythrocyte hemoglobin content. The changes observed in erythrocytes of RP-treated rats may serve as an additional criterion for evaluation of hypervitaminosis A severity.

Effect of solution non-ideality on erythrocyte volume regulation.

PubMed

Levin, R L; Cravalho, E G; Huggins, C E

1977-03-01

A non-ideal, hydrated, non-dilute pseudo-binary salt-protein-water solution model of the erythrocyte intracellular solution is presented to describe the osmotic behavior of human erythrocytes. Existing experimental activity data for salts and proteins in aqueous solutions are used to formulate van Laar type expressions for the solvent and solute activity coefficients. Reasonable estimates can therefore be made of the non-ideality of the erythrocyte intracellular solution over a wide range of osmolalities. Solution non-ideality is shown to affect significantly the degree of solute polarization within the erythrocyte intracellular solution during freezing. However, the non-ideality has very little effect upon the amount of water retained within erythrocytes cooled at sub-zero temperatures.

Cysticercosis in laboratory rabbits.

PubMed

Owiny, J R

2001-03-01

There are no data on the current incidence of Taenia pisiformis in laboratory rabbits. Two cases of cysticercosis most likely due to T. pisiformis in laboratory rabbits (intermediate host) are presented. Both rabbits had no contact with dogs (final host); their caretakers did not work with dogs, and these caretakers changed into facility scrubs and wore gloves when working with the rabbits. Rabbit 1 may have been infected after being fed hay at our facility. In light of the life cycle of the parasite and the history of rabbit 2, it potentially could have been infected prior to arrival at our facility. There have been only three cases of tapeworm cysts in rabbits in our facility (average daily census, 250) during the last 10 years (incidence, < 1%). This report indicates that although cysticercosis is rare in laboratory rabbits, one should always be aware of such incidental findings. Although it may not produce overt illness in the rabbit, hepatic migration could adversely affect the outcome of some experimental procedures

Dynamic adhesion of eryptotic erythrocytes to immobilized platelets via platelet phosphatidylserine receptors.

PubMed

Walker, Britta; Towhid, Syeda T; Schmid, Evi; Hoffmann, Sascha M; Abed, Majed; Münzer, Patrick; Vogel, Sebastian; Neis, Felix; Brucker, Sara; Gawaz, Meinrad; Borst, Oliver; Lang, Florian

2014-02-01

Glucose depletion of erythrocytes triggers suicidal erythrocyte death or eryptosis, which leads to cell membrane scrambling with phosphatidylserine exposure at the cell surface. Eryptotic erythrocytes adhere to endothelial cells by a mechanism involving phosphatidylserine at the erythrocyte surface and CXCL16 as well as CD36 at the endothelial cell membrane. Nothing has hitherto been known about an interaction between eryptotic erythrocytes and platelets, the decisive cells in primary hemostasis and major players in thrombotic vascular occlusion. The present study thus explored whether and how glucose-depleted erythrocytes adhere to platelets. To this end, adhesion of phosphatidylserine-exposing erythrocytes to platelets under flow conditions was examined in a flow chamber model at arterial shear rates. Platelets were immobilized on collagen and further stimulated with adenosine diphosphate (ADP, 10 μM) or thrombin (0.1 U/ml). As a result, a 48-h glucose depletion triggered phosphatidylserine translocation to the erythrocyte surface and augmented the adhesion of erythrocytes to immobilized platelets, an effect significantly increased upon platelet stimulation. Adherence of erythrocytes to platelets was blunted by coating of erythrocytic phosphatidylserine with annexin V or by neutralization of platelet phosphatidylserine receptors CXCL16 and CD36 with respective antibodies. In conclusion, glucose-depleted erythrocytes adhere to platelets. The adhesive properties of platelets are augmented by platelet activation. Erythrocyte adhesion to immobilized platelets requires phosphatidylserine at the erythrocyte surface and CXCL16 as well as CD36 expression on platelets. Thus platelet-mediated erythrocyte adhesion may foster thromboocclusive complications in diseases with stimulated phosphatidylserine exposure of erythrocytes.

Focusing and alignment of erythrocytes in a viscoelastic medium

NASA Astrophysics Data System (ADS)

Go, Taesik; Byeon, Hyeokjun; Lee, Sang Joon

2017-01-01

Viscoelastic fluid flow-induced cross-streamline migration has recently received considerable attention because this process provides simple focusing and alignment over a wide range of flow rates. The lateral migration of particles depends on the channel geometry and physicochemical properties of particles. In this study, digital in-line holographic microscopy (DIHM) is employed to investigate the lateral migration of human erythrocytes induced by viscoelastic fluid flow in a rectangular microchannel. DIHM provides 3D spatial distributions of particles and information on particle orientation in the microchannel. The elastic forces generated in the pressure-driven flows of a viscoelastic fluid push suspended particles away from the walls and enforce erythrocytes to have a fixed orientation. Blood cell deformability influences the lateral focusing and fixed orientation in the microchannel. Different from rigid spheres and hardened erythrocytes, deformable normal erythrocytes disperse from the channel center plane, as the flow rate increases. Furthermore, normal erythrocytes have a higher angle of inclination than hardened erythrocytes in the region near the side-walls of the channel. These results may guide the label-free diagnosis of hematological diseases caused by abnormal erythrocyte deformability.

Analysis of free zone electrophoresis of fixed erythrocytes performed in microgravity

NASA Technical Reports Server (NTRS)

Snyder, Robert S.; Rhodes, Percy H.; Herren, Blair J.; Miller, Teresa Y.; Seaman, Geoffrey V. F.

1985-01-01

A free fluid zone electrophoresis experiment was performed in the microgravity environment of Space Shuttle flight STS-3 (March 1983). The experiment was designed to confirm observations made on the Apollo-Soyuz mission of 1975 and to test the effect of high red blood cell (RBC) concentration on free fluid electrophoresis. Photographic documentation of cell zone progression in one-hour separations of mixtures of formaldehyde-fixed human and rabbit erythrocytes, which were subjected to a field of approximately 13 V/cm in low ionic strength buffer, was analyzed. One of two columns contained 2 x 10 to the 8th RBC/ml; (low concentration), and the other contained 1 x 10 to the 9th RBC/ml (high concentration). The observed and calculated leading edge displacements of the RBC in the two columns were in agreement, indicating the absence of unexpected effects of the reduced gravity environment. Post-flight analyses of the contents of the columns was not possible, and additional microgravity experiments are needed to evaluate the role of particle-particle interactions in concentrated suspensions undergoing electrophoresis.

The Effect of Sepsis on the Erythrocyte

PubMed Central

Bateman, Ryon M.; Sharpe, Michael D.; Singer, Mervyn; Ellis, Christopher G.

2017-01-01

Sepsis induces a wide range of effects on the red blood cell (RBC). Some of the effects including altered metabolism and decreased 2,3-bisphosphoglycerate are preventable with appropriate treatment, whereas others, including decreased erythrocyte deformability and redistribution of membrane phospholipids, appear to be permanent, and factors in RBC clearance. Here, we review the effects of sepsis on the erythrocyte, including changes in RBC volume, metabolism and hemoglobin’s affinity for oxygen, morphology, RBC deformability (an early indicator of sepsis), antioxidant status, intracellular Ca2+ homeostasis, membrane proteins, membrane phospholipid redistribution, clearance and RBC O2-dependent adenosine triphosphate efflux (an RBC hypoxia signaling mechanism involved in microvascular autoregulation). We also consider the causes of these effects by host mediated oxidant stress and bacterial virulence factors. Additionally, we consider the altered erythrocyte microenvironment due to sepsis induced microvascular dysregulation and speculate on the possible effects of RBC autoxidation. In future, a better understanding of the mechanisms involved in sepsis induced erythrocyte pathophysiology and clearance may guide improved sepsis treatments. Evidence that small molecule antioxidants protect the erythrocyte from loss of deformability, and more importantly improve septic patient outcome suggest further research in this area is warranted. While not generally considered a critical factor in sepsis, erythrocytes (and especially a smaller subpopulation) appear to be highly susceptible to sepsis induced injury, provide an early warning signal of sepsis and are a factor in the microvascular dysfunction that has been associated with organ dysfunction. PMID:28885563

The Effect of Sepsis on the Erythrocyte.

PubMed

Bateman, Ryon M; Sharpe, Michael D; Singer, Mervyn; Ellis, Christopher G

2017-09-08

Sepsis induces a wide range of effects on the red blood cell (RBC). Some of the effects including altered metabolism and decreased 2,3-bisphosphoglycerate are preventable with appropriate treatment, whereas others, including decreased erythrocyte deformability and redistribution of membrane phospholipids, appear to be permanent, and factors in RBC clearance. Here, we review the effects of sepsis on the erythrocyte, including changes in RBC volume, metabolism and hemoglobin's affinity for oxygen, morphology, RBC deformability (an early indicator of sepsis), antioxidant status, intracellular Ca 2+ homeostasis, membrane proteins, membrane phospholipid redistribution, clearance and RBC O₂-dependent adenosine triphosphate efflux (an RBC hypoxia signaling mechanism involved in microvascular autoregulation). We also consider the causes of these effects by host mediated oxidant stress and bacterial virulence factors. Additionally, we consider the altered erythrocyte microenvironment due to sepsis induced microvascular dysregulation and speculate on the possible effects of RBC autoxidation. In future, a better understanding of the mechanisms involved in sepsis induced erythrocyte pathophysiology and clearance may guide improved sepsis treatments. Evidence that small molecule antioxidants protect the erythrocyte from loss of deformability, and more importantly improve septic patient outcome suggest further research in this area is warranted. While not generally considered a critical factor in sepsis, erythrocytes (and especially a smaller subpopulation) appear to be highly susceptible to sepsis induced injury, provide an early warning signal of sepsis and are a factor in the microvascular dysfunction that has been associated with organ dysfunction.

Comparative serological investigation between cat and tiger blood for transfusion

PubMed Central

THENGCHAISRI, Naris; SINTHUSINGHA, Chayakrit; ARTHITWONG, Surapong; SATTASATHUCHANA, Panpicha

2017-01-01

Evidence suggests that non-domesticated felids inherited the same AB-erythrocyte antigens as domestic cats. To study the possible compatibility of tiger blood with that of other endangered felidae, blood samples from captive tigers and domestic cats were subjected to an in vitro study. The objectives of this study were to (1) identify whether the captive tigers had blood type AB and (2) determine the compatibility between the blood of captive tigers and that of domestic cats with a similar blood type. The anti-coagulated blood with ethylenediaminetetraacetic acid of 30 tigers was examined to determine blood type, and a crossmatching test was performed between tiger and cat blood. All 30 tigers had blood type A. Tube agglutination tests using tiger plasma with cat erythrocytes resulted in 100% agglutination (n=30) with type B cat erythrocytes and 76.7% agglutination (n=23) with type A cat erythrocytes. The 80% of major and 60% of minor compatibilities between blood from 10 tigers and 10 domestic cats with blood type A were found to pass compatibility tests. Interestingly, 3/10 of the tigers’ red blood cell samples were fully compatible with all cat plasmas, and 1/10 of the tiger plasma samples were fully compatible with the type A red cells of domestic cats. Although the result of present findings revealed type-A blood group in the surveyed tigers, the reaction of tiger plasma with Type-A red cell from cats suggested a possibility of other blood type in tigers. PMID:28450662

Comparative serological investigation between cat and tiger blood for transfusion.

PubMed

Thengchaisri, Naris; Sinthusingha, Chayakrit; Arthitwong, Surapong; Sattasathuchana, Panpicha

2017-06-29

Evidence suggests that non-domesticated felids inherited the same AB-erythrocyte antigens as domestic cats. To study the possible compatibility of tiger blood with that of other endangered felidae, blood samples from captive tigers and domestic cats were subjected to an in vitro study. The objectives of this study were to (1) identify whether the captive tigers had blood type AB and (2) determine the compatibility between the blood of captive tigers and that of domestic cats with a similar blood type. The anti-coagulated blood with ethylenediaminetetraacetic acid of 30 tigers was examined to determine blood type, and a crossmatching test was performed between tiger and cat blood. All 30 tigers had blood type A. Tube agglutination tests using tiger plasma with cat erythrocytes resulted in 100% agglutination (n=30) with type B cat erythrocytes and 76.7% agglutination (n=23) with type A cat erythrocytes. The 80% of major and 60% of minor compatibilities between blood from 10 tigers and 10 domestic cats with blood type A were found to pass compatibility tests. Interestingly, 3/10 of the tigers' red blood cell samples were fully compatible with all cat plasmas, and 1/10 of the tiger plasma samples were fully compatible with the type A red cells of domestic cats. Although the result of present findings revealed type-A blood group in the surveyed tigers, the reaction of tiger plasma with Type-A red cell from cats suggested a possibility of other blood type in tigers.

Erythrocyte membrane stability to hydrogen peroxide is decreased in Alzheimer disease.

PubMed

Gilca, Marilena; Lixandru, Daniela; Gaman, Laura; Vîrgolici, Bogdana; Atanasiu, Valeriu; Stoian, Irina

2014-01-01

The brain and erythrocytes have similar susceptibility toward free radicals. Therefore, erythrocyte abnormalities might indicate the progression of the oxidative damage in Alzheimer disease (AD). The aim of this study was to investigate erythrocyte membrane stability and plasma antioxidant status in AD. Fasting blood samples (from 17 patients with AD and 14 healthy controls) were obtained and erythrocyte membrane stability against hydrogen peroxide and 2,2'-azobis-(2-amidinopropane) dihydrochloride (AAPH), serum Trolox equivalent antioxidant capacity (TEAC), residual antioxidant activity or gap (GAP), erythrocyte catalase activity (CAT), erythrocyte superoxide dismutase (SOD) activity, erythrocyte nonproteic thiols, and total plasma thiols were determined. A significant decrease in erythrocyte membrane stability to hydrogen peroxide was found in AD patients when compared with controls (P<0.05). On the contrary, CAT activity (P<0.0001) and total plasma thiols (P<0.05) were increased in patients with AD compared with controls. Our results indicate that the most satisfactory measurement of the oxidative stress level in the blood of patients with AD is the erythrocyte membrane stability to hydrogen peroxide. Reduced erythrocyte membrane stability may be further evaluated as a potential peripheral marker for oxidative damage in AD.

Erythrocyte and platelet fatty acids in retinitis pigmentosa.

PubMed

Stanzial, A M; Bonomi, L; Cobbe, C; Olivieri, O; Girelli, D; Trevisan, M T; Bassi, A; Ferrari, S; Corrocher, R

1991-05-01

The fatty acid composition and the glutathione-peroxidase activity (GSH-Px) of erythrocytes and platelets, the production of malondialdehyde (MDA) by platelets and the activity of the main systems of transmembrane cation transport in erythrocyte have been studied in 12 patients (5 males and 7 females) affected by retinitis pigmentosa (RP). A remarkable increase of saturated fatty acids (SFA), particularly of stearic acid (C18:0), has been noted in these patients. The reduced unsaturated/saturated fatty acids ratio (PUFA/SFA) observed in both erythrocytes and platelets and the decrease of arachidonic acid in platelets may depend by an active peroxidation process as documented by the increase of MDA. Platelet glutathione-peroxidase (PTL-GSH-PX) and plasma retinol were in the normal range, whereas erythrocyte glutathione-peroxidase (E-GSH-PX), MDA and plasma alfa-toco-pherol were increased in patients with RP. The activities of Na(+)-K+ pump, cotransport and Na(+)-Li+ countertransport were normal in RP erythrocytes.

Lead isotopic studies of lunar soils - Their bearing on the time scale of agglutinate formation

NASA Technical Reports Server (NTRS)

Church, S. E.; Tilton, G. R.; Chen, J. H.

1976-01-01

Fines (smaller than 75 microns) and bulk soil were studied to analyze loss of volatile lead; losses of the order of 10% to 30% radiogenic lead during the production of agglutinates are assessed. Lead isotope data from fine-agglutinate pairs are analyzed for information on the time scale of micrometeorite bombardment, from the chords generated by the data in concordia diagrams. Resulting mean lead loss ages were compared to spallogenic gas exposure ages for all samples. Labile parentless radiogenic Pb residing preferentially on or in the fines is viewed as possibly responsible for aberrant lead loss ages. Bulk soils plot above the concordia curve (in a field of excess radiogenic Pb) for all samples with anomalous ages.

Agglutinated foraminifera from the Ludlow (Silurian) of Ireland

NASA Astrophysics Data System (ADS)

Kaminski, Michael; Ferretti, Annalisa; Messori, Fabio; Papazzoni, Cesare Andrea; Sevastopulo, George

2017-04-01

Agglutinated foraminifera are one of the most primitive groups of foraminifera, possibly already appearing in the Cryogenian but usually rare in lower Paleozoic rocks. Their mean standing diversity slowly increased during Cambrian and Ordovician times, reaching a stable value of about 50 genera in the mid-Silurian which remained fairly constant up to the Triassic. An assemblage of agglutinated foraminifera was unexpectedly found in conodont residue from material collected in the Dingle Peninsula, County Kerry, southwestern Ireland. This material comes from rare calcareous occurrences in volcanoclastics previously known for their rich trilobite and conodont assemblages. The limestones are trilobite-crinoidal silty wackestone to packstone, with local brachiopod concentrations, documenting brachiopod-trilobite-crinoidal dominated communities of shallow and well-ventilated water that might have periodically colonized the bottom intercalating with volcanic events and then successively redeposited in deeper waters. The conodont fauna indicates an early Ludlow (Gorstian-earliest Ludfordian) age (Kaminski et al., 2016). The foraminiferal assemblage has limited potential for stratigraphical correlation as long-range taxa are present, but it represents the first record from the Silurian of Ireland. The assemblage is dominated by tubothalamids (Rectoammodiscus and rare Sansabaina), with less abundant monothalamids (Psammosiphonella and Psammosphaera). The assemblage displays low diversity compared with other assemblages described from the British Isles (Kircher & Brasier, 1989). At the species level, this assemblage is identical to those described previously from the Silurian of North America but with lower diversity. Only Rectoammodiscus diai had apparently a wider geographic distribution, including not only the central USA (Oklahoma and Kansas) but also the Welsh Borderlands and Senegal. The affinities with the assemblages reported at several localities in the central

Kinetics of viral load and erythrocytic inclusion body formation in pacific herring artificially infected with erythrocytic necrosis virus

USGS Publications Warehouse

Glenn, Jolene A.; Emmenegger, Eveline J.; Grady, Courtney A.; Roon, Sean R.; Gregg, Jacob L.; Conway, Carla M.; Winton, James R.; Hershberger, Paul K.

2012-01-01

Viral erythrocytic necrosis (VEN) is a condition that affects marine and anadromous fish species, including herrings and salmonids, in the Atlantic and Pacific oceans. Infection is frequently associated with severe anemia and causes episodic mortality among wild and hatchery fish when accompanied by additional stressors; VEN can be presumptively diagnosed by (1) light microscopic identification of a single characteristic—a round, magenta-colored, 0.8-μm-diameter inclusion body (IB) within the cytoplasm of erythrocytes and their precursors on Giemsa-stained blood films; or (2) observation (via transmission electron microscopy [TEM]) of the causative iridovirus, erythrocytic necrosis virus (ENV), within erythrocytes or their precursors. To better understand the kinetics of VEN, specific-pathogen-free Pacific herring Clupea pallasii were infected with ENV by intraperitoneal injection. At 1, 4, 7, 10, 14, 21, and 28 d postexposure, samples of blood, spleen, and kidney were collected and assessed (1) via light microscopy for the number of intracytoplasmic IBs in blood smears and (2) via TEM for the number of virions within erythrocytes. The mean prevalence of intracytoplasmic IBs in the blood cells increased from 0% at 0–4 d postexposure to 94% at 28 d postexposure. Viral load within circulating red blood cells peaked at 7 d postexposure, fell slightly, and then reached a plateau. However, blood cells observed within the kidney and spleen tissues demonstrated high levels of ENV between 14 and 28 d postexposure. The results indicate that the viral load within erythrocytes does not correlate well with IB prevalence and that the virus can persist in infected fish for more than 28 d.

False-positive cryptococcal antigen latex agglutination caused by disinfectants and soaps.

PubMed Central

Blevins, L B; Fenn, J; Segal, H; Newcomb-Gayman, P; Carroll, K C

1995-01-01

Five disinfectants or soaps were tested to determine if any could be responsible for false-positive results obtained with the Latex-Crypto Antigen Detection System kit (Immuno-Mycologics, Inc., Norman, Okla.). Three disinfectants or soaps (Derma soap, 7X, and Bacdown) produced false-positive agglutination after repeated washing of ring slides during testing of a known negative cerebrospinal fluid specimen. PMID:7650214

Factors influencing erythrocyte choline concentrations.

PubMed

Miller, B L; Jenden, D J; Tang, C; Read, S

1989-01-01

Choline concentrations in human erythrocytes increase after freezing and thawing, during incubation in Krebs-phosphate for 30 min or on storage at 0 degrees C for 3-24 hr. The increase is prevented by protein precipitation by 10% perchloric acid, 10% zinc hydroxide, 10% sodium tungstate or boiling in water. It is not prevented by EDTA (10 mM) and is increased by oleate (5 mM). We suggest that the increase is due to the action of phospholipase D on erythrocyte phospholipids.

Response of the iron-deficient erythrocyte in the rat to hyperoxia

NASA Technical Reports Server (NTRS)

Larkin, E. C.; Kimzey, S. L.; Siler, K.

1978-01-01

Normal and iron-deficient rats were exposed to 90% O2 at 760 Torr for 24 or 48 h. Erythrocyte response to hyperoxia was monitored by potassium (rubidium) influx studies, by storage stress, and by ultrastructural studies. Normal rat erythrocytes exhibited morphological changes and decrease of ouabain-sensitive potassium influx compared to unexposed controls. Both components of erythrocyte potassium influx were affected by iron deficiency. Erythrocytes from unexposed iron-deficient rats showed a 50% increase in ouabain-sensitive potassium influx compared to controls. Iron-deficient rats exposed to hyperoxia for 24 or 48 h, had erythrocytes with morphological changes. Erythrocytes of iron-deficient rats exposed for 24 h showned no influx change; those exposed for 48 h showed a decrease of ouabain-sensitive influx compared to erythrocytes of controls.

ABO Blood Groups Influence Macrophage-mediated Phagocytosis of Plasmodium falciparum-infected Erythrocytes

PubMed Central

Branch, Donald R.; Hult, Annika K.; Olsson, Martin L.; Liles, W. Conrad; Cserti-Gazdewich, Christine M.; Kain, Kevin C.

2012-01-01

Erythrocyte polymorphisms associated with a survival advantage to Plasmodium falciparum infection have undergone positive selection. There is a predominance of blood group O in malaria-endemic regions, and several lines of evidence suggest that ABO blood groups may influence the outcome of P. falciparum infection. Based on the hypothesis that enhanced innate clearance of infected polymorphic erythrocytes is associated with protection from severe malaria, we investigated whether P. falciparum-infected O erythrocytes are more efficiently cleared by macrophages than infected A and B erythrocytes. We show that human macrophages in vitro and mouse monocytes in vivo phagocytose P. falciparum-infected O erythrocytes more avidly than infected A and B erythrocytes and that uptake is associated with increased hemichrome deposition and high molecular weight band 3 aggregates in infected O erythrocytes. Using infected A1, A2, and O erythrocytes, we demonstrate an inverse association of phagocytic capacity with the amount of A antigen on the surface of infected erythrocytes. Finally, we report that enzymatic conversion of B erythrocytes to type as O before infection significantly enhances their uptake by macrophages to observed level comparable to that with infected O wild-type erythrocytes. These data provide the first evidence that ABO blood group antigens influence macrophage clearance of P. falciparum-infected erythrocytes and suggest an additional mechanism by which blood group O may confer resistance to severe malaria. PMID:23071435

High-Throughput Incubation and Quantification of Agglutination Assays in a Microfluidic System.

PubMed

Castro, David; Conchouso, David; Kodzius, Rimantas; Arevalo, Arpys; Foulds, Ian G

2018-06-04

In this paper, we present a two-phase microfluidic system capable of incubating and quantifying microbead-based agglutination assays. The microfluidic system is based on a simple fabrication solution, which requires only laboratory tubing filled with carrier oil, driven by negative pressure using a syringe pump. We provide a user-friendly interface, in which a pipette is used to insert single droplets of a 1.25-µL volume into a system that is continuously running and therefore works entirely on demand without the need for stopping, resetting or washing the system. These assays are incubated by highly efficient passive mixing with a sample-to-answer time of 2.5 min, a 5⁻10-fold improvement over traditional agglutination assays. We study system parameters such as channel length, incubation time and flow speed to select optimal assay conditions, using the streptavidin-biotin interaction as a model analyte quantified using optical image processing. We then investigate the effect of changing the concentration of both analyte and microbead concentrations, with a minimum detection limit of 100 ng/mL. The system can be both low- and high-throughput, depending on the rate at which assays are inserted. In our experiments, we were able to easily produce throughputs of 360 assays per hour by simple manual pipetting, which could be increased even further by automation and parallelization. Agglutination assays are a versatile tool, capable of detecting an ever-growing catalog of infectious diseases, proteins and metabolites. A system such as this one is a step towards being able to produce high-throughput microfluidic diagnostic solutions with widespread adoption. The development of analytical techniques in the microfluidic format, such as the one presented in this work, is an important step in being able to continuously monitor the performance and microfluidic outputs of organ-on-chip devices.

A comparison of sperm agglutination and immobilization assays with a quantitative ELISA for anti-sperm antibody in serum.

PubMed

Lynch, D M; Leali, B A; Howe, S E

1986-08-01

An enzyme-linked immunosorbent assay (ELISA) that quantitates antisperm antibody in serum was compared with standard sperm agglutination and immobilization assays with the use of sera from 40 normal and 292 subfertile individuals. Quantitation of the assay was accomplished by standardizing assay parameters, including the incorporation of a standard reference curve, the number of whole target sperm, the optimal dilution of serum, the selection of microtiter plate, and the time and temperatures involved in the adsorption and incubation phases. With this method, the level of antisperm antibody binding to target sperm in 40 normal fertile individuals was found to be 2.3 (+/- 1.1 standard deviation [SD]) fg immunoglobulin (Ig)/sperm. An increased mean level of 7.4 +/- 3.7 fg Ig/sperm was determined in 84 infertile patients with positive agglutination and/or immobilization tests. In 208 individuals with negative agglutination and immobilization tests the mean concentration of antisperm antibody was 2.5 +/- 1.3 fg Ig/sperm. Postvasectomy patients assayed by this method had a mean Ig binding value of 7.1 +/- 2.4 fg Ig/sperm. The infertile group with positive agglutination and/or immobilization tests had a significantly higher mean antisperm antibody level than the normal fertile group, according to the Student's t-test for independent samples (P less than 0.001). This indirect serum-based assay reproducibly quantitates antisperm antibody binding to whole target sperm, suggests the normal and abnormal levels of antisperm antibody, and correlates with standard functional assays.

RNA-Seq Reveals an Integrated Immune Response in Nucleated Erythrocytes

PubMed Central

Morera, Davinia; Roher, Nerea; Ribas, Laia; Balasch, Joan Carles; Doñate, Carmen; Callol, Agnes; Boltaña, Sebastian; Roberts, Steven; Goetz, Giles; Goetz, Frederick W.; MacKenzie, Simon A.

2011-01-01

Background Throughout the primary literature and within textbooks, the erythrocyte has been tacitly accepted to have maintained a unique physiological role; namely gas transport and exchange. In non-mammalian vertebrates, nucleated erythrocytes are present in circulation throughout the life cycle and a fragmented series of observations in mammals support a potential role in non-respiratory biological processes. We hypothesised that nucleated erythrocytes could actively participate via ligand-induced transcriptional re-programming in the immune response. Methodology/Principal Findings Nucleated erythrocytes from both fish and birds express and regulate specific pattern recognition receptor (PRR) mRNAs and, thus, are capable of specific pathogen associated molecular pattern (PAMP) detection that is central to the innate immune response. In vitro challenge with diverse PAMPs led to de novo specific mRNA synthesis of both receptors and response factors including interferon-alpha (IFNα) that exhibit a stimulus-specific polysomal shift supporting active translation. RNA-Seq analysis of the PAMP (Poly (I∶C), polyinosinic∶polycytidylic acid)-erythrocyte response uncovered diverse cohorts of differentially expressed mRNA transcripts related to multiple physiological systems including the endocrine, reproductive and immune. Moreover, erythrocyte-derived conditioned mediums induced a type-1 interferon response in macrophages thus supporting an integrative role for the erythrocytes in the immune response. Conclusions/Significance We demonstrate that nucleated erythrocytes in non-mammalian vertebrates spanning significant phylogenetic distance participate in the immune response. RNA-Seq studies highlight a mRNA repertoire that suggests a previously unrecognized integrative role for the erythrocytes in other physiological systems. PMID:22046430

Modeling of Virion Collisions in Cervicovaginal Mucus Reveals Limits on Agglutination as the Protective Mechanism of Secretory Immunoglobulin A

PubMed Central

Chen, Alex; McKinley, Scott A.; Shi, Feng; Wang, Simi; Mucha, Peter J.; Harit, Dimple; Forest, M. Gregory; Lai, Samuel K.

2015-01-01

Secretory immunoglobulin A (sIgA), a dimeric antibody found in high quantities in the gastrointestinal mucosa, is broadly associated with mucosal immune protection. A distinguishing feature of sIgA is its ability to crosslink pathogens, thereby creating pathogen/sIgA aggregates that are too large to traverse the dense matrix of mucin fibers in mucus layers overlying epithelial cells and consequently reducing infectivity. Here, we use modeling to investigate this mechanism of “immune exclusion” based on sIgA-mediated agglutination, in particular the potential use of sIgA to agglutinate HIV in cervicovaginal mucus (CVM) and prevent HIV transmission. Utilizing reported data on HIV diffusion in CVM and semen, we simulate HIV collision kinetics in physiologically-thick mucus layers–a necessary first step for sIgA-induced aggregation. We find that even at the median HIV load in semen of acutely infected individuals possessing high viral titers, over 99% of HIV virions will penetrate CVM and reach the vaginal epithelium without colliding with another virion. These findings imply that agglutination is unlikely to be the dominant mechanism of sIgA-mediated protection against HIV or other sexually transmitted pathogens. Rather, we surmise that agglutination is most effective against pathogens either present at exceedingly high concentrations or that possess motility mechanisms other than Brownian diffusion that significantly enhance encounter rates. PMID:26132216

The erythrocyte sodium and potassium in patients treated with digoxin.

PubMed Central

Morgan, D B; Cumberbatch, M; Cohn, S; Scott, D; Gunasuntharam, T; Davidson, C; Chapman, C

1980-01-01

1 Four healthy persons and ten patients with heart failure were studied for 5 to 20 days after they started taking digoxin. The sodium content of their erythrocytes increased and there was an equimolar decrease in potassium content. 2 The increase in erythrocyte sodium for a given increase in plasma digoxin during this acute digitalization was less on average and varied more in the patients than in the healthy persons, that is the patients' erythrocytes were less responsive to digoxin. 3 The average erythrocyte sodium was greater in 183 patients who had been taking digoxin for at least 2 months than in 100 healthy persons not taking digoxin but there was no significant correlation between the plasma digoxin concentrations and erythrocyte sodium concentration in the patients. Indeed, there was no apparent change in the erythrocyte sodium in many of the patients taking digoxin. 4 If the erythrocyte sodium concentration is a reliable guide to the tissue effects of digoxin then the results suggest that there is a wide variation in the response to digoxin between patients both during acute digitalization and during chronic treatment with digoxin. PMID:7426274

Transformation of Human Erythrocyte Shape by Endotoxic Lipopolysaccharide

PubMed Central

Warren, John R.; Harris, Alan S.; Wallas, Charles H.

1983-01-01

Human erythrocytes were observed to undergo a discocyte to echinocyte to spheroechinocyte shape transformation during brief incubation with endotoxic lipopolysaccharide. It was concluded that lipopolysaccharide-membrane interactions alter the curvature of erythrocyte membranes. Images PMID:6822423

Erythrocyte survival time in Greyhounds as assessed by use of in vivo biotinylation.

PubMed

Garon, Catherine L; Cohn, Leah A; Scott, Michael A

2010-09-01

To determine erythrocyte survival time in Greyhounds. 6 Greyhounds used as blood donors and 3 privately owned non-Greyhound dogs. In vivo biotinylation of erythrocytes was performed by infusion of biotin-N-hydroxysuccinimide into each dog via a jugular vein catheter. Blood samples were collected 12 hours later and then at weekly intervals and were used to determine the percentage of biotin-labeled erythrocytes at each time point. Erythrocytes were washed, incubated with avidin-fluorescein isothiocyanate, and washed again before the percentage of biotinylated erythrocytes was measured by use of flow cytometry. Survival curves for the percentage of biotinylated erythrocytes were generated, and erythrocyte survival time was defined as the x-intercept of a least squares best-fit line for the linear portion of each curve. The R2 for survival curves ranged from 0.93 to 0.99 during the first 10 weeks after infusion of erythrocytes. Erythrocyte survival time for the 3 non-Greyhound dogs was 94, 98, and 116 days, respectively, which was consistent with previously reported values. Erythrocyte survival time for the 6 Greyhounds ranged from 83 to 110 days (mean, 93 days; median, 88 days). As determined by use of in vivo biotinylation, erythrocyte survival times in Greyhounds were similar to those determined for non-Greyhound dogs and did not differ significantly from erythrocyte survival times reported previously for non-Greyhound dogs. Erythrocyte survival time was similar in Greyhounds and non-Greyhound dogs. Greyhounds can be used as erythrocyte donors without concerns about inherently shorter erythrocyte survival time.

Anti-Self Phosphatidylserine Antibodies Recognize Uninfected Erythrocytes Promoting Malarial Anemia.

PubMed

Fernandez-Arias, Cristina; Rivera-Correa, Juan; Gallego-Delgado, Julio; Rudlaff, Rachel; Fernandez, Clemente; Roussel, Camille; Götz, Anton; Gonzalez, Sandra; Mohanty, Akshaya; Mohanty, Sanjib; Wassmer, Samuel; Buffet, Pierre; Ndour, Papa Alioune; Rodriguez, Ana

2016-02-10

Plasmodium species, the parasitic agents of malaria, invade erythrocytes to reproduce, resulting in erythrocyte loss. However, a greater loss is caused by the elimination of uninfected erythrocytes, sometimes long after infection has been cleared. Using a mouse model, we found that Plasmodium infection induces the generation of anti-self antibodies that bind to the surface of uninfected erythrocytes from infected, but not uninfected, mice. These antibodies recognize phosphatidylserine, which is exposed on the surface of a fraction of uninfected erythrocytes during malaria. We find that phosphatidylserine-exposing erythrocytes are reticulocytes expressing high levels of CD47, a "do-not-eat-me" signal, but the binding of anti-phosphatidylserine antibodies mediates their phagocytosis, contributing to anemia. In human patients with late postmalarial anemia, we found a strong inverse correlation between the levels of anti-phosphatidylserine antibodies and plasma hemoglobin, suggesting a similar role in humans. Inhibition of this pathway may be exploited for treating malarial anemia. Copyright © 2016 Elsevier Inc. All rights reserved.

Morphometric analysis of erythrocytes from patients with thalassemia using tomographic diffractive microscopy

NASA Astrophysics Data System (ADS)

Lin, Yang-Hsien; Huang, Shin-Shyang; Wu, Shang-Ju; Sung, Kung-Bin

2017-11-01

Complete blood count is the most common test to detect anemia, but it is unable to obtain the abnormal shape of erythrocytes, which highly correlates with the hematologic function. Tomographic diffractive microscopy (TDM) is an emerging technique capable of quantifying three-dimensional (3-D) refractive index (RI) distributions of erythrocytes without labeling. TDM was used to characterize optical and morphological properties of 172 erythrocytes from healthy volunteers and 419 erythrocytes from thalassemic patients. To efficiently extract and analyze the properties of erythrocytes, we developed an adaptive region-growing method for automatically delineating erythrocytes from 3-D RI maps. The thalassemic erythrocytes not only contained lower hemoglobin content but also showed doughnut shape and significantly lower volume, surface area, effective radius, and average thickness. A multi-indices prediction model achieved perfect accuracy of diagnosing thalassemia using four features, including the optical volume, surface-area-to-volume ratio, sphericity index, and surface area. The results demonstrate the ability of TDM to provide quantitative, hematologic measurements and to assess morphological features of erythrocytes to distinguish healthy and thalassemic erythrocytes.

Antioxidative and Cholesterol-Lowering Effects of Lemon Essential Oil in Hypercholesterolemia-Induced Rabbits

PubMed Central

Lee, Hyunjoo; Woo, Minji; Kim, Mijeong; Noh, Jeong Sook

2018-01-01

The cholesterol-lowering and anti-atherogenic effects of lemon essential oil (LEO) were investigated and compared with the effects of limonene. Owing to their volatility, both LEO and limonene were microencapsulated before preparation of the diet (20%, w/w). Hypercholesterolemia-induced rabbits were divided into 3 groups based on plasma total cholesterol (TC) levels and fed coating matrix (control group), LEO (LEO group), or limonene (Limonene group) for 8 weeks. LEO dose-dependently inhibited low-density lipoprotein oxidation in vitro. Plasma TC levels were the lowest in the LEO group (P<0.05). Erythrocytes in the LEO group had a normal disc shape, whereas the erythrocytes in the limonene and control groups were aggregated and star-shaped, respectively. The aortic intima thickness was thinnest in the LEO group followed by the control and limonene groups. Plasma TC lowering and anti-atherogenic effects of LEO were greater than limonene, suggesting that other bioactive compounds besides limonene in LEO might contribute to these effects. The bioactive compounds in LEO were limonene (67.57%), β-pinene (10.00%), and γ-terpinene (9.95%). In addition, sabinene, α-pinene, myrcene, and geranial were also present but the amount was in the range of 1~2%. Several bioactive compounds were also detected. In conclusion, LEO had beneficial effects on hypercholesterolemia due to its antioxidative and cholesterol lowering effects. PMID:29662842

Tolerance of Erythrocytes in Poultry: Induction and Specificity

PubMed Central

Mitchison, N. A.

1962-01-01

Measurement of the rate of elimination of 51Cr-labelled erythrocytes provides a reliable test of immunity in fowls. Chickens can be rendered tolerant of homologous and turkey erythrocytes, as judged by this test, by receiving a series of transfusions of irradiated blood. The series were arranged so that foreign cells remained present in the circulation from the time of hatching. Tolerance induced by this treatment is generally incomplete, but can last indefinitely. In some chickens the manifestation of tolerance of turkey erythrocytes is delayed, probably because of passive transmission of antibody from the dam. Chickens old enough to react against small transfusions of homologous blood can still be rendered tolerant by massive transfusions. Tolerance of the erythrocytes from an individual donor extends only slightly to those from other donors. Tolerance acquired in this way, through transfusion of irradiated blood, stands in contrast to the more stable and complete tolerance that can be acquired through administration of viable cells. Viable cells, on the other hand, provide a less sensitive test, for birds which tolerate skin homografts often eliminate rapidly erythrocytes from the same donor. PMID:14474652

Light-induced protoporphyrin release from erythrocytes in erythropoietic protoporphyria.

PubMed Central

Sandberg, S; Brun, A

1982-01-01

The photohemolysis of normal erythrocytes incubated with protoporphyrin is reduced in the presence of albumin. When globin is added to normal erythrocytes loaded with protoporphyrin, protoporphyrin is bound to globin. During irradiation protoporphyrin moves from globin to the erythrocyte membrane and photohemolysis is initiated. Erythrocytes in patients with erythropoietic protoporphyria contain large amounts of protoporphyrin bound to hemoglobin. Upon irradiation of these cells in the absence of albumin, 40% of protoporphyrin and 80% of hemoglobin is released after 240 kJ/m2. The released protoporphyrin is hemoglobin bound. In contrast, when albumin is present only 8% of hemoglobin is released whereas protoporphyrin is released to 76%. The released protoporphyrin is albumin bound. A hypothesis for the release of erythrocyte protoporphyrin in erythropoietic protoporphyria without simultaneous hemolysis is proposed. Upon irradiation protoporphyrin photodamages its binding sites on hemoglobin, moves through the plasma membrane, and is bound to albumin in plasma. PMID:7107898

Experiment study and FEM simulation on erythrocytes under linear stretching of optical micromanipulation

NASA Astrophysics Data System (ADS)

Liu, Ying; Song, Huadong; Zhu, Panpan; Lu, Hao; Tang, Qi

2017-08-01

The elasticity of erythrocytes is an important criterion to evaluate the quality of blood. This paper presents a novel research on erythrocytes' elasticity with the application of optical tweezers and the finite element method (FEM) during blood storage. In this work, the erythrocytes with different in vitro times were linearly stretched by trapping force using optical tweezers and the time dependent elasticity of erythrocytes was investigated. The experimental results indicate that the membrane shear moduli of erythrocytes increased with the increasing in vitro time, namely the elasticity was decreasing. Simultaneously, an erythrocyte shell model with two parameters (membrane thickness h and membrane shear modulus H) was built to simulate the linear stretching states of erythrocytes by the FEM, and the simulations conform to the results obtained in the experiment. The evolution process was found that the erythrocytes membrane thicknesses were decreasing. The analysis assumes that the partial proteins and lipid bilayer of erythrocyte membrane were decomposed during the in vitro preservation of blood, which results in thin thickness, weak bending resistance, and losing elasticity of erythrocyte membrane. This study implies that the FEM can be employed to investigate the inward mechanical property changes of erythrocyte in different environments, which also can be a guideline for studying the erythrocyte mechanical state suffered from different diseases.

Proteome analysis of the triton-insoluble erythrocyte membrane skeleton.

PubMed

Basu, Avik; Harper, Sandra; Pesciotta, Esther N; Speicher, Kaye D; Chakrabarti, Abhijit; Speicher, David W

2015-10-14

Erythrocyte shape and membrane integrity is imparted by the membrane skeleton, which can be isolated as a Triton X-100 insoluble structure that retains the biconcave shape of intact erythrocytes, indicating isolation of essentially intact membrane skeletons. These erythrocyte "Triton Skeletons" have been studied morphologically and biochemically, but unbiased proteome analysis of this substructure of the membrane has not been reported. In this study, different extraction buffers and in-depth proteome analyses were used to more fully define the protein composition of this functionally critical macromolecular complex. As expected, the major, well-characterized membrane skeleton proteins and their associated membrane anchors were recovered in good yield. But surprisingly, a substantial number of additional proteins that are not considered in erythrocyte membrane skeleton models were recovered in high yields, including myosin-9, lipid raft proteins (stomatin, flotillin1 and 2), multiple chaperone proteins (HSPs, protein disulfide isomerase and calnexin), and several other proteins. These results show that the membrane skeleton is substantially more complex than previous biochemical studies indicated, and it apparently has localized regions with unique protein compositions and functions. This comprehensive catalog of the membrane skeleton should lead to new insights into erythrocyte membrane biology and pathogenic mutations that perturb membrane stability. Biological significance Current models of erythrocyte membranes describe fairly simple homogenous structures that are incomplete. Proteome analysis of the erythrocyte membrane skeleton shows that it is quite complex and includes a substantial number of proteins whose roles and locations in the membrane are not well defined. Further elucidation of interactions involving these proteins and definition of microdomains in the membrane that contain these proteins should yield novel insights into how the membrane skeleton

Influence of styryl dyes on blood erythrocytes

NASA Astrophysics Data System (ADS)

Nizomov, Negmat; Barakaeva, Mubaro; Kurtaliev, Eldar N.; Rahimov, Sherzod I.; Khakimova, Dilorom P.; Khodjayev, Gayrat; Yashchuk, Valeriy N.

2008-08-01

It was studied the influence of F, Sbt, Sil, Sbo monomer and homodimer Dst-5, Dst-10, Dbt-5, Dbt-10, Dil-10, Dbo-10 styryl dyes on blood erythrocytes of white rats. It was shown that the homodimer styryl dyes Dst-5, Dbt-5 and Dbo-10 decrease the erythrocytes quantity by 1.5-2 times more as compared with monomer dyes Sbt and Sbo. The main cause of dyes different action is the different oxidation degree of intracellular hemoglobin evoked by these dyes. It was established that the observed effects was connected with different penetration of these dyes through membrane of erythrocytes and with interaction of these dyes with albumin localized in membranes of cells.

The Role and Mechanism of Erythrocyte Invasion by Francisella tularensis.

PubMed

Schmitt, Deanna M; Barnes, Rebecca; Rogerson, Taylor; Haught, Ashley; Mazzella, Leanne K; Ford, Matthew; Gilson, Tricia; Birch, James W-M; Sjöstedt, Anders; Reed, Douglas S; Franks, Jonathan M; Stolz, Donna B; Denvir, James; Fan, Jun; Rekulapally, Swanthana; Primerano, Donald A; Horzempa, Joseph

2017-01-01

Francisella tularensis is an extremely virulent bacterium that can be transmitted naturally by blood sucking arthropods. During mammalian infection, F. tularensis infects numerous types of host cells, including erythrocytes. As erythrocytes do not undergo phagocytosis or endocytosis, it remains unknown how F. tularensis invades these cells. Furthermore, the consequence of inhabiting the intracellular space of red blood cells (RBCs) has not been determined. Here, we provide evidence indicating that residing within an erythrocyte enhances the ability of F. tularensis to colonize ticks following a blood meal. Erythrocyte residence protected F. tularensis from a low pH environment similar to that of gut cells of a feeding tick. Mechanistic studies revealed that the F. tularensis type VI secretion system (T6SS) was required for erythrocyte invasion as mutation of mglA (a transcriptional regulator of T6SS genes), dotU , or iglC (two genes encoding T6SS machinery) severely diminished bacterial entry into RBCs. Invasion was also inhibited upon treatment of erythrocytes with venom from the Blue-bellied black snake ( Pseudechis guttatus ), which aggregates spectrin in the cytoskeleton, but not inhibitors of actin polymerization and depolymerization. These data suggest that erythrocyte invasion by F. tularensis is dependent on spectrin utilization which is likely mediated by effectors delivered through the T6SS. Our results begin to elucidate the mechanism of a unique biological process facilitated by F. tularensis to invade erythrocytes, allowing for enhanced colonization of ticks.

The Role and Mechanism of Erythrocyte Invasion by Francisella tularensis

PubMed Central

Schmitt, Deanna M.; Barnes, Rebecca; Rogerson, Taylor; Haught, Ashley; Mazzella, Leanne K.; Ford, Matthew; Gilson, Tricia; Birch, James W.-M.; Sjöstedt, Anders; Reed, Douglas S.; Franks, Jonathan M.; Stolz, Donna B.; Denvir, James; Fan, Jun; Rekulapally, Swanthana; Primerano, Donald A.; Horzempa, Joseph

2017-01-01

Francisella tularensis is an extremely virulent bacterium that can be transmitted naturally by blood sucking arthropods. During mammalian infection, F. tularensis infects numerous types of host cells, including erythrocytes. As erythrocytes do not undergo phagocytosis or endocytosis, it remains unknown how F. tularensis invades these cells. Furthermore, the consequence of inhabiting the intracellular space of red blood cells (RBCs) has not been determined. Here, we provide evidence indicating that residing within an erythrocyte enhances the ability of F. tularensis to colonize ticks following a blood meal. Erythrocyte residence protected F. tularensis from a low pH environment similar to that of gut cells of a feeding tick. Mechanistic studies revealed that the F. tularensis type VI secretion system (T6SS) was required for erythrocyte invasion as mutation of mglA (a transcriptional regulator of T6SS genes), dotU, or iglC (two genes encoding T6SS machinery) severely diminished bacterial entry into RBCs. Invasion was also inhibited upon treatment of erythrocytes with venom from the Blue-bellied black snake (Pseudechis guttatus), which aggregates spectrin in the cytoskeleton, but not inhibitors of actin polymerization and depolymerization. These data suggest that erythrocyte invasion by F. tularensis is dependent on spectrin utilization which is likely mediated by effectors delivered through the T6SS. Our results begin to elucidate the mechanism of a unique biological process facilitated by F. tularensis to invade erythrocytes, allowing for enhanced colonization of ticks. PMID:28536678

Acetylsalicylic acid (aspirin) and salicylic acid interaction with the human erythrocyte membrane bilayer induce in vitro changes in the morphology of erythrocytes.

PubMed

Suwalsky, Mario; Belmar, Jessica; Villena, Fernando; Gallardo, María José; Jemiola-Rzeminska, Malgorzata; Strzalka, Kazimierz

2013-11-01

Despite the well-documented information, there are insufficient reports concerning the effects of salicylate compounds on the structure and functions of cell membranes, particularly those of human erythrocytes. With the aim to better understand the molecular mechanisms of the interaction of acetylsalicylic acid (ASA) and salicylic acid (SA) with cell membranes, human erythrocyte membranes and molecular models were utilized. These consisted of bilayers of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), representative of phospholipid classes located in the outer and inner monolayers of the human erythrocyte membrane, respectively. The capacity of ASA and SA to perturb the multibilayer structures of DMPC and DMPE was evaluated by X-ray diffraction while DMPC unilamellar vesicles (LUV) were studied by fluorescence spectroscopy. Moreover, we took advantage of the capability of differential scanning calorimetry (DSC) to detect the changes in the thermotropic phase behavior of lipid bilayers resulting from ASA and SA interaction with PC and PE molecules. In an attempt to further elucidate their effects on cell membranes, the present work also examined their influence on the morphology of intact human erythrocytes by means of defocusing and scanning electron microscopy, while isolated unsealed human erythrocyte membranes (IUM) were studied by fluorescence spectroscopy. Results indicated that both salicylates interact with human erythrocytes and their molecular models in a concentration-dependent manner perturbing their bilayer structures. Copyright © 2013 Elsevier Inc. All rights reserved.

Zoonoses of rabbits and rodents.

PubMed

Hill, William Allen; Brown, Julie Paige

2011-09-01

Millions of households in the US own rabbits or rodents, including hamsters, guinea pigs, and gerbils. Activities such as hunting and camping also involve human interactions with wild rabbits and rodents. In many environments, feral rabbits and rodents live in close proximity to humans, domesticated animals, and other wildlife. Education of rodent and rabbit owners and individuals with occupational or recreational exposures to these species is paramount to reduce the prevalence of zoonoses associated with rabbit and rodent exposure.

Erythrocyte Membrane Failure by Electromechanical Stress.

PubMed

Du, E; Qiang, Yuhao; Liu, Jia

2018-01-01

We envision that electrodeformation of biological cells through dielectrophoresis as a new technique to elucidate the mechanistic details underlying membrane failure by electrical and mechanical stresses. Here we demonstrate the full control of cellular uniaxial deformation and tensile recovery in biological cells via amplitude-modified electric field at radio frequency by an interdigitated electrode array in microfluidics. Transient creep and cyclic experiments were performed on individually tracked human erythrocytes. Observations of the viscoelastic-to-viscoplastic deformation behavior and the localized plastic deformations in erythrocyte membranes suggest that electromechanical stress results in irreversible membrane failure. Examples of membrane failure can be separated into different groups according to the loading scenarios: mechanical stiffening, physical damage, morphological transformation from discocyte to echinocyte, and whole cell lysis. These results show that this technique can be potentially utilized to explore membrane failure in erythrocytes affected by other pathophysiological processes.

Impacts of papain and neuraminidase enzyme treatment on electrohydrodynamics and IgG-mediated agglutination of type A red blood cells.

PubMed

Hyono, Atsushi; Gaboriaud, Fabien; Mazda, Toshio; Takata, Youichi; Ohshima, Hiroyuki; Duval, Jérôme F L

2009-09-15

The stability of native and enzyme-treated human red blood cells of type A (Rh D positive) against agglutination is investigated under conditions where it is mediated by immunoglobuline G (IgG) anti-D antibody binding. The propensity of cells to agglutinate is related to their interphasic (electrokinetic) properties. These properties significantly depend on the concentration of proteolytic papain enzyme and protease-free neuraminidase enzyme that the cells are exposed to. The analysis is based on the interpretation of electrophoretic data of cells by means of the numerical theory for the electrokinetics of soft (bio)particles. A significant reduction of the hydrodynamic permeability of the external soft glycoprotein layer of the cells is reported under the action of papain. This reflects a significant decrease in soft surface layer thickness and a loss in cell surface integrity/rigidity, as confirmed by nanomechanical AFM analysis. Neuraminidase action leads to an important decrease in the interphase charge density by removing sialic acids from the cell soft surface layer. This is accompanied by hydrodynamic softness modulations less significant than those observed for papain-treated cells. On the basis of these electrohydrodynamic characteristics, the overall interaction potential profiles between two native cells and two enzyme-treated cells are derived as a function of the soft surface layer thickness in the Debye-Hückel limit that is valid for cell suspensions under physiological conditions (approximately 0.16 M). The thermodynamic computation of cell suspension stability against IgG-mediated agglutination then reveals that a decrease in the cell surface layer thickness is more favorable than a decrease in interphase charge density for inducing agglutination. This is experimentally confirmed by agglutination data collected for papain- and neuraminidase-treated cells.

Erythrocyte signal transduction pathways, their oxygenation dependence and functional significance.

PubMed

Barvitenko, Nadezhda N; Adragna, Norma C; Weber, Roy E

2005-01-01

Erythrocytes play a key role in human and vertebrate metabolism. Tissue O2 supply is regulated by both hemoglobin (Hb)-O2 affinity and erythrocyte rheology, a key determinant of tissue perfusion. Oxygenation-deoxygenation transitions of Hb may lead to re-organization of the cytoskeleton and signalling pathways activation/deactivation in an O2-dependent manner. Deoxygenated Hb binds to the cytoplasmic domain of the anion exchanger band 3, which is anchored to the cytoskeleton, and is considered a major mechanism underlying the oxygenation-dependence of several erythrocyte functions. This work discusses the multiple modes of Hb-cytoskeleton interactions. In addition, it reviews the effects of Mg2+, 2,3-diphosphoglycerate, NO, shear stress and Ca2+, all factors accompanying the oxygenation-deoxygenation cycle in circulating red cells. Due to the extensive literature on the subject, the data discussed here, pertain mainly to human erythrocytes whose O2 affinity is modulated by 2,3-diphosphoglycerate, ectothermic vertebrate erythrocytes that use ATP, and to bird erythrocytes that use inositol pentaphosphate. Copyright 2005 S. Karger AG, Basel.

Dog erythrocyte antigens 1.1, 1.2, 3, 4, 7, and Dal blood typing and cross-matching by gel column technique.

PubMed

Kessler, Rebecca J; Reese, Jessica; Chang, Denise; Seth, Mayank; Hale, Anne S; Giger, Urs

2010-09-01

Testing for canine blood types other than dog erythrocyte antigen 1.1 (DEA 1.1) is controversial and complicated by reagent availability and methodology. The objectives of this study were to use available gel column technology to develop an extended blood-typing method using polyclonal reagents for DEA 1.1, 1.2, 3, 4, 7, and Dal and to assess the use of gel columns for cross-matching. Dogs (43-75) were typed for DEA 1.1, 1.2, 3, 4, 7, and Dal. METHODS included tube agglutination (Tube) using polyclonal reagents, a commercially available DEA 1.1 gel column test kit (Standard-Gel) using monoclonal reagent, and multiple gel columns (Extended-Gel) using polyclonal reagents. Blood from 10 recipient and 15 donor dogs was typed as described above and cross-matched using the gel column technique. Of 43 dogs typed for DEA 1.1, 23, 25, and 20 dogs were positive using Standard-Gel, Extended-Gel, and Tube, respectively. Typing for DEA 1.2 was not achievable with Extended-Gel. For 75 dogs typed for DEA 3, 4, and 7, concordance of Extended-Gel with Tube was 94.7%, 100%, and 84%, respectively. Dal, determined only by Extended-Gel, was positive for all dogs. Post-transfusion major cross-matches were incompatible in 10 of 14 pairings, but none were associated with demonstrable blood type incompatibilities. Gel column methodology can be adapted for use with polyclonal reagents for detecting DEA 1.1, 3, 4, 7, and Dal. Agglutination reactions are similar between Extended-Gel and Tube, but are more easily interpreted with Extended-Gel. When using gel columns for cross-matching, incompatible blood cross-matches can be detected following sensitization by transfusion, although in this study incompatibilities associated with any tested DEA or Dal antigens were not found. ©2010 American Society for Veterinary Clinical Pathology.

Peroxiredoxin 2 and peroxide metabolism in the erythrocyte.

PubMed

Low, Felicia M; Hampton, Mark B; Winterbourn, Christine C

2008-09-01

Peroxiredoxin 2 (Prx2) is an antioxidant enzyme that uses cysteine residues to decompose peroxides. Prx2 is the third most abundant protein in erythrocytes, and competes effectively with catalase and glutathione peroxidase to scavenge low levels of hydrogen peroxide, including that derived from hemoglobin autoxidation. Low thioredoxin reductase activity in the erythrocyte is able to keep up with this basal oxidation and maintain the Prx2 in its reduced form, but exposure to exogenous hydrogen peroxide causes accumulation of the disulfide-linked dimer. The high cellular concentration means that although turnover is slow, erythrocyte Prx2 can act as a noncatalytic scavenger of hydrogen peroxide and a sink for hydrogen peroxide before turnover becomes limiting. The consequences of Prx2 oxidation for the erythrocyte are not well characterized, but mice deficient in this protein develop severe hemolytic anemia associated with Heinz body formation. Prx2, also known as calpromotin, regulates ion transport by associating with the membrane and activating the Gárdos channel. How Prx2 redox transformations are linked to membrane association and channel activation is yet to be established. In this review, we discuss the functional properties of Prx2 and its role as a major component of the erythrocyte antioxidant system.

Monosaccharide uptake by erythrocytes of the embryonic and adult chicken.

PubMed

Ingermann, R L; Stock, M K; Metcalfe, J; Bissonnette, J M

1985-01-01

Rates of monosaccharide uptake by adult and 10-18 day old embryonic chicken erythrocytes were quantitated. The rate of carrier-mediated, stereospecific transport decreased 28% from day 10 to day 14 of incubation and was unchanged thereafter. At no time, however, did the rate of carrier-mediated transport by embryonic erythrocytes differ significantly from that of the adult cells. The rate of transfer by simple diffusion was 3-5 fold faster in embryonic than in adult erythrocytes. Uptake by simple diffusion decreased slightly as the embryo developed. Chronic hyperoxic incubation (70% O2) had little influence on total monosaccharide uptake by embryonic erythrocytes.

In Vitro Protective Effect of Phikud Navakot Extraction on Erythrocyte

PubMed Central

2016-01-01

Phikud Navakot (PN), Thai herbal remedy in National List of Essential Medicines, has been claimed to reduce many cardiovascular symptoms especially dizziness and fainting. Apart from blood supply, erythrocyte morphology, in both shape and size, is one of the main consideration factors in cardiovascular diseases and may be affected by vascular oxidative stress. However, little is known about antioxidative property of PN on erythrocyte to preserve red blood cell integrity. In this study, 1,000 μM hydrogen peroxide-induced oxidative stress was conducted on sheep erythrocyte. Three doses of PN (1, 0.5, and 0.25 mg/mL) and 10 μM of ascorbic acid were compared. The released hemoglobin absorbance was measured to demonstrate hemolysis. Electron microscopic and immunohistochemical studies were also performed to characterize dysmorphic erythrocyte and osmotic ability in relation to aquaporin- (AQP-) 1 expression, respectively. The results revealed that all doses of PN and ascorbic acid decreased the severity of dysmorphic erythrocyte, particularly echinocyte, acanthocyte, knizocyte, codocyte, clumping, and other malformations. However, the most effective was 0.5 mg/mL PN dosage. In addition, hydrostatic pressure may be increased in dysmorphic erythrocyte in association with AQP-1 upregulation. Our results demonstrated that PN composes antioxidative effect to maintain the integrity and osmotic ability on sheep erythrocyte. PMID:28003847

Nanoscale Mineralogy and Composition of Experimental Regolith Agglutinates Produced under Asteroidal Impact Conditions

NASA Technical Reports Server (NTRS)

Christoffersen, Roy; Cintala, M. J.; Keller, L. P.; See, T. H.; Horz, F.

2013-01-01

On the Moon, the energetics of smaller impactors and the physical/chemical characteristics of the granular regolith target combine to form a key product of lunar space weathering: chemically reduced shock melts containing optically-active nanophase Fe metal grains (npFe0) [1]. In addition to forming the optically dark glassy matrix phase in lunar agglutinitic soil particles [1], these shock melts are becoming increasingly recognized for their contribution to optically active patina coatings on a wide range of exposed rock and grain surfaces in the lunar regolith [2]. In applying the lessons of lunar space weathering to asteroids, the potential similarities and differences in regolith-hosted shock melts on the Moon compared to those on asteroids has become a topic of increasing interest [3,4]. In a series of impact experiments performed at velocities applicable to the asteroid belt [5], Horz et al. [6] and See and Horz [7] have previously shown that repeated impacts into a gabbroic regolith analog target can produce melt-welded grain aggregates morphologically very similar to lunar agglutinates [6,7]. Although these agglutinate-like particles were extensively analyzed by electron microprobe and scanning electron microscopy (SEM) as part of the original study [7], a microstructural and compositional comparison of these aggregates to lunar soil agglutinates at sub-micron scales has yet to be made. To close this gap, we characterized a representative set of these aggregates using a JEOL 7600 field-emission scanning electron microscope (FE-SEM), and JEOL 2500SE field-emission scanning transmission electron microscope (FE-STEM) both optimized for energy dispersive X-ray spectroscopy (EDX) compositional spectrum imaging at respective analytical spatial resolutions of 0.5 to 1 micron, and 2 to 4 nm.

MEMS reagent and sample handling procedure: Feasibility of viral antibody detection by passive immune agglutination

NASA Technical Reports Server (NTRS)

Bailey, G. D.; Tenoso, H. J.

1975-01-01

An attempt was made to develop a test requiring no preadsorption steps for the assessment of antibodies to rubella and mumps viruses using the passive immune agglutination (PIA) method. Both rubella and mumps antigens and antibodies were prepared. Direct PIA tests, using rubella antigen-coated beads, and indirect PIA tests, using rubella antibody-coated beads, were investigated. Attempts, using either method, were unsuccessful. Serum interference along with nonspecific agglutination of beads by the rubella antigen resulted in no specific response under the test conditions investigated. A new, highly sensitive approach, the enzyme immunoassay (EIA) test system, is recommended to overcome the nonspecificity. This system is a logical outgrowth of some of the solid phase work done on MEMS and represents the next generation tests system that can be directly applied to early disease detection and monitoring.

Engineering antigens for in situ erythrocyte binding induces T-cell deletion.

PubMed

Kontos, Stephan; Kourtis, Iraklis C; Dane, Karen Y; Hubbell, Jeffrey A

2013-01-02

Antigens derived from apoptotic cell debris can drive clonal T-cell deletion or anergy, and antigens chemically coupled ex vivo to apoptotic cell surfaces have been shown correspondingly to induce tolerance on infusion. Reasoning that a large number of erythrocytes become apoptotic (eryptotic) and are cleared each day, we engineered two different antigen constructs to target the antigen to erythrocyte cell surfaces after i.v. injection, one using a conjugate with an erythrocyte-binding peptide and another using a fusion with an antibody fragment, both targeting the erythrocyte-specific cell surface marker glycophorin A. Here, we show that erythrocyte-binding antigen is collected much more efficiently than free antigen by splenic and hepatic immune cell populations and hepatocytes, and that it induces antigen-specific deletional responses in CD4(+) and CD8(+) T cells. We further validated T-cell deletion driven by erythrocyte-binding antigens using a transgenic islet β cell-reactive CD4(+) T-cell adoptive transfer model of autoimmune type 1 diabetes: Treatment with the peptide antigen fused to an erythrocyte-binding antibody fragment completely prevented diabetes onset induced by the activated, autoreactive CD4(+) T cells. Thus, we report a translatable modular biomolecular approach with which to engineer antigens for targeted binding to erythrocyte cell surfaces to induce antigen-specific CD4(+) and CD8(+) T-cell deletion toward exogenous antigens and autoantigens.

Serotyping of Actinobacillus pleuropneumoniae serotype 5 strains using a monoclonal-based polystyrene agglutination test.

PubMed Central

Dubreuil, J D; Letellier, A; Stenbaek, E; Gottschalk, M

1996-01-01

A polystyrene agglutination test has been developed for serotyping Actinobacillus pleuropneumoniae serotype 5a and 5b strains. Protein A-coated polystyrene microparticles were sensitized with a murine monoclonal antibody recognizing an epitope on serotype 5 LPS-O chain as shown by SDS-PAGE and Western blotting. A total of 205 A. pleuropneumoniae, strains including all 12 serotype reference strains and 13 strains representing 8 common bacterial species associated with swine or related to A. pleuropneumoniae, were tested by mixing 25 microL of polystyrene reagent with the same volume of a dense suspension of bacterial cells grown for 18 h. All A. pleuropneumoniae strains had been previously serotyped using standard procedures. The polystyrene agglutination test was rapid (less than 3 min) and easy to perform. Overall a very good correlation (97.3%) with the standard techniques was found. The sensitized polystyrene particles were stable for at least 6 mo. Images Figure 1. PMID:8825998

Abnormalities of the erythrocyte membrane.

PubMed

Gallagher, Patrick G

2013-12-01

Primary abnormalities of the erythrocyte membrane are characterized by clinical, laboratory, and genetic heterogeneity. Among this group, hereditary spherocytosis patients are more likely to experience symptomatic anemia. Treatment of hereditary spherocytosis with splenectomy is curative in most patients. Growing recognition of the long-term risks of splenectomy has led to re-evaluation of the role of splenectomy. Management guidelines acknowledge these considerations and recommend discussion between health care providers, patient, and family. The hereditary elliptocytosis syndromes are the most common primary disorders of erythrocyte membrane proteins. However, most elliptocytosis patients are asymptomatic and do not require therapy. Copyright © 2013 Elsevier Inc. All rights reserved.

Autoantibodies against the inner aspect of erythrocyte membranes in NZB mice.

PubMed Central

Linder, E

1977-01-01

Erythrocyte autoantibodies in NZB mice react by hemagglutination methods with exposed and hidden red cell antigens. The hidden antigens can be exposed by treatment with proteolytic enzymes. By indirect immunofluorescence one antibody population can be shown to react with modified red cells. In the present study the location of the corresponding autoantigen within the membrane was studied. Mechanical or hypotonic lysis of the red cells exposed the antigen. Proteolytic digestion known to expose other erythrocyte autoantigens had no effect. The autoantigen was exposed on 'inside out' erythrocyte membrane vesicles, but not on 'right-side out' vesicles, prepared from isolated erythrocyte ghosts. Frezzing and thawing as well as mechanical disintergration of red cells liberated antigenically active material as saline-insuluble fibrillar material. The observations indicate that the autoantigen studied is located at the inner aspect of the erythrocyte membrane and suggest that it is associated with fibril-forming structural components. The observed reactivity distinguishes the described antibodies from previously identified erythrocyte autoantibodies. PMID:862240

Prevalence of dog erythrocyte antigens in retired racing Greyhounds.

PubMed

Iazbik, Maria Cristina; O'Donnell, Margee; Marin, Liliana; Zaldivar, Sara; Hudson, Dawn; Couto, C Guillermo

2010-12-01

Blood groups in dogs are designated as dog erythrocyte antigen (DEA) 1.1, 1.2, 3, 4, 5, 7, and Dal. There is limited information about the frequency of different antigens in Greyhound dogs, despite their frequent use as blood donors. The aims of this study were to determine the frequencies of DEA 1.1, 1.2, 3, 4, 5, and 7 in Greyhounds, to compare the frequencies with those of non-Greyhound dogs, and to evaluate the presence of naturally occurring anti-DEA antibodies. Blood was collected from 206 Greyhound and 66 non-Greyhound dogs being screened as potential blood donors. Blood-typing was performed at Animal Blood Resources International by tube agglutination utilizing polyclonal anti-DEA antibodies. Of the Greyhound dogs, 27/206 (13.1%) were positive for DEA 1.1, and this frequency was significantly lower (P<.0001) than for non-Greyhound dogs of which 40/66 (60.6%) were DEA 1.1-positive. The frequency of positivity for both DEA 1.1 and 1.2 was also lower in Greyhounds (P<.0001). There were no significant differences between Greyhounds and non-Greyhounds for DEA 1.2, 3, 4, 5, or 7. All 137 dogs (113 Greyhounds and 24 non-Greyhounds) that were evaluated for naturally occurring anti-DEA antibodies in serum were negative. A higher percentage of Greyhound dogs (57.3%, 118/206) were considered "universal donors" (negative for all DEAs except DEA 4) compared with non-Greyhound dogs (28%, 13/46). The frequency of positivity for DEA 1.1 in our population of Greyhounds was significantly lower than previously reported for dogs. Furthermore, a large majority of Greyhounds met the criteria for universal donors. ©2010 American Society for Veterinary Clinical Pathology.

The binding of calcium ions by erythrocytes and `ghost'-cell membranes

PubMed Central

Long, C.; Mouat, Barbara

1971-01-01

1. Washed human erythrocytes, suspended in iso-osmotic sucrose containing 2.5mm-calcium chloride, bind about 400μg-atoms of calcium/litre of packed cells. Sucrose may be replaced by other sugars. 2. Partial replacement of sucrose by iso-osmotic potassium chloride diminishes the uptake of calcium, 50% inhibition occurring at about 50mm-potassium chloride. 3. Other univalent cations behave like potassium, whereas bivalent cations are much more inhibitory. The tervalent cations, yttrium and lanthanum, however, are the most effective inhibitors of calcium uptake. 4. An approximate correlation exists between the calcium uptake and the sialic acid content of erythrocytes of various species and of human erythrocytes that have been partially depleted of sialic acid by treatment with neuraminidase. However, even after complete removal of sialic acid, human erythrocytes still bind about 140μg-atoms of calcium/litre of packed cells. 5. A Scatchard (1949) plot of calcium uptake at various Ca2+ concentrations in the suspending media shows the presence of three different binding sites on the external surface of the human erythrocyte membrane. 6. Erythrocyte `ghost' cells, the membranes of which appear to be permeable to Ca2+ ions, can bind about 1000μg-atoms of calcium per `ghost'-cell equivalent of 1 litre of packed erythrocytes. This indicates that there are also binding sites for calcium on the internal surface of the erythrocyte membrane. PMID:5124387

Erythrocyte deformability and oxidative stress in inflammatory bowel disease.

PubMed

Akman, Tulay; Akarsu, Mesut; Akpinar, Hale; Resmi, Halil; Taylan, Ebru; Sezer, Ebru

2012-02-01

Oxidative stress and reduced microvascular flow are important factors in the pathogenesis of inflammatory bowel disease (IBD). The increased oxidative stress reduces the erythrocyte deformability. However, in IBD, there are no studies in the literature which evaluate erythrocyte deformability. In our study, we investigated the effect of oxidative stress and erythrocyte deformability in IBD. Forty-three patients with active IBD, 48 patients with inactive IBD and 45 healthy controls were included. The erytrocyte deformability, malonyldialdehyde levels, glutation peroxidase and sulfhydryl levels were measured in peripheral venous blood samples. Erytrocyte malonyldialdehyde levels in both active and inactive IBD were significantly increased compared with control groups. Plasma glutation peroxidase levels did not show statistically significant difference between all groups. The decreased plasma sulfhydryl levels in active IBD were statistically significant compared with both the inactive IBD and the control group, but plasma sulfhydryl levels in inactive IBD group did not show statistically significant differences when compared with the control group. Elongation index values in both active and inactive IBD increased significantly compared with the control group. Statistically significant correlations were not found between the elongation index and glutation peroxidase, malonyldialdehyde, sulfhydryl levels in all groups. Our study is the first to evaluate the erythrocyte deformability in IBD. In our study, increased erytrocyte malonyldialdehyde levels and decreased plasma sulfhydryl levels manifested the role of oxidative stress in the pathogenesis of the disease. It is thought that the increased erythrocyte malonyldialdehyde values cause the reduction in erythrocyte deformability.

Genetic Characterization of Escherichia coli Type 1 Pilus Adhesin Mutants and Identification of a Novel Binding Phenotype

PubMed Central

Hamrick, Terri S.; Harris, Sandra L.; Spears, Patricia A.; Havell, Edward A.; Horton, John R.; Russell, Perry W.; Orndorff, Paul E.

2000-01-01

Five Escherichia coli type 1 pilus mutants that had point mutations in fimH, the gene encoding the type 1 pilus adhesin FimH, were characterized. FimH is a minor component of type 1 pili that is required for the pili to bind and agglutinate guinea pig erythrocytes in a mannose-inhibitable manner. Point mutations were located by DNA sequencing and deletion mapping. All mutations mapped within the signal sequence or in the first 28% of the predicted mature protein. All mutations were missense mutations except for one, a frameshift lesion that was predicted to cause the loss of approximately 60% of the mature FimH protein. Bacterial agglutination tests with polyclonal antiserum raised to a LacZ-FimH fusion protein failed to confirm that parental amounts of FimH cross-reacting material were expressed in four of the five mutants. The remaining mutant, a temperature-sensitive (ts) fimH mutant that agglutinated guinea pig erythrocytes after growth at 31°C but not at 42°C, reacted with antiserum at both temperatures in a manner similar to the parent. Consequently, this mutant was chosen for further study. Temperature shift experiments revealed that new FimH biosynthesis was required for the phenotypic change. Guinea pig erythrocyte and mouse macrophage binding experiments using the ts mutant grown at the restrictive and permissive temperatures revealed that whereas erythrocyte binding was reduced to a level comparable to that of a fimH insertion mutant at the restrictive temperature, mouse peritoneal macrophages were bound with parental efficiency at both the permissive and restrictive temperatures. Also, macrophage binding by the ts mutant was insensitive to mannose inhibition after growth at 42°C but sensitive after growth at 31°C. The ts mutant thus binds macrophages with one receptor specificity at 31°C and another at 42°C. PMID:10869080

Amodiaquine failure associated with erythrocytic glutathione in Plasmodium falciparum malaria

PubMed Central

Zuluaga, Lina; Pabón, Adriana; López, Carlos; Ochoa, Aleida; Blair, Silvia

2007-01-01

Objective To establish the relationship between production of glutathione and the therapeutic response to amodiaquine (AQ) monotherapy in Plasmodium falciparum non-complicated malaria patients. Methodology Therapeutic response to AQ was evaluated in 32 patients with falciparum malaria in two townships of Antioquia, Colombia, and followed-up for 28 days. For every patient, total glutathione and enzymatic activity (glutathione reductase, GR, and γ-glutamylcysteine synthetase, γ-GCS) were determined in parasitized erythrocytes, non-infected erythrocytes and free parasites, on the starting day (day zero, before ingestion of AQ) and on the day of failure (in case of occurrence). Results There was found an AQ failure of 31.25%. Independent of the therapeutic response, on the starting day and on the day of failure, lower total glutathione concentration and higher GR activities in parasitized erythrocytes were found, compared with non-infected erythrocytes (p < 0.003). In addition, only on the day of failure, γ-GCS activity of parasitized erythrocytes was higher, compared with that of healthy erythrocytes (p = 0.01). Parasitized and non-parasitized erythrocytes in therapeutic failure patients (TF) had higher total glutathione on the starting day compared with those of adequate clinical response (ACR) (p < 0.02). Parasitized erythrocytes of TF patients showed lower total glutathione on the failure day, compared with starting day (p = 0.017). No differences was seen in the GR and γ-GCS activities by compartment, neither between the two therapeutic response groups nor between the two treatment days. Conclusion This study is a first approach to explaining P. falciparum therapeutic failure in humans through differences in glutathione metabolism in TF and ACR patients. These results suggest a role for glutathione in the therapeutic failure to antimalarials. PMID:17451604

Evaluation of a latex agglutination assay for the identification of Burkholderia pseudomallei and Burkholderia mallei.

PubMed

Duval, Brea D; Elrod, Mindy G; Gee, Jay E; Chantratita, Narisara; Tandhavanant, Sarunporn; Limmathurotsakul, Direk; Hoffmaster, Alex R

2014-06-01

Cases of melioidosis and glanders are rare in the United States, but the etiologic agents of each disease (Burkholderia pseudomallei and Burkholderia mallei, respectively) are classified as Tier 1 select agents because of concerns about their potential use as bioterrorism agents. A rapid, highly sensitive, and portable assay for clinical laboratories and field use is required. Our laboratory has further evaluated a latex agglutination assay for its ability to identify B. pseudomallei and B. mallei isolates. This assay uses a monoclonal antibody that specifically recognizes the capsular polysaccharide produced by B. pseudomallei and B. mallei, but is absent in closely related Burkholderia species. A total of 110 B. pseudomallei and B. mallei were tested, and 36 closely related Burkholderia species. The latex agglutination assay was positive for 109 of 110 (99.1% sensitivity) B. pseudomallei and B. mallei isolates tested. © The American Society of Tropical Medicine and Hygiene.

Increased calcium deposits and decreased Ca2+ -ATPase in erythrocytes of ascitic broiler chickens.

PubMed

Li, Kai; Zhao, Lihong; Geng, Guangrui; Ma, Liqin; Dong, Shishan; Xu, Tong; Wang, Jianlin; Wang, Huiyu; Tian, Yong; Qiao, Jian

2011-06-01

The decrease of erythrocyte deformability may be one of the predisposing factors for pulmonary hypertension and ascites in broiler chickens. In mammals, the cytoplasmic calcium is a major regulator of erythrocyte deformability. In this study, the erythrocyte deformability was measured, and the precise locations of Ca2+ and Ca2+ -ATPase in the erythrocytes were investigated in chickens with ascites syndrome induced by low ambient temperature. The results showed that ascitic broilers had higher filtration index of erythrocyte compared with control groups, indicating a decrease in erythrocyte deformability in ascitic broilers. The more calcium deposits were observed in the erythrocytes of ascitic broilers compared with those of the age-matched control birds. The Ca2+ -ATPase reactive grains were significantly decreased on the erythrocyte membranes of ascitic broilers. Our data suggest that accumulation of intracellular calcium and inhibition of Ca2+ -ATPase might be important factors for the reduced deformability of the erythrocytes of ascitic broilers. Copyright © 2010 Elsevier Ltd. All rights reserved.

Functional consequences of sphingomyelinase-induced changes in erythrocyte membrane structure.

PubMed

Dinkla, S; Wessels, K; Verdurmen, W P R; Tomelleri, C; Cluitmans, J C A; Fransen, J; Fuchs, B; Schiller, J; Joosten, I; Brock, R; Bosman, G J C G M

2012-10-18

Inflammation enhances the secretion of sphingomyelinases (SMases). SMases catalyze the hydrolysis of sphingomyelin into phosphocholine and ceramide. In erythrocytes, ceramide formation leads to exposure of the removal signal phosphatidylserine (PS), creating a potential link between SMase activity and anemia of inflammation. Therefore, we studied the effects of SMase on various pathophysiologically relevant parameters of erythrocyte homeostasis. Time-lapse confocal microscopy revealed a SMase-induced transition from the discoid to a spherical shape, followed by PS exposure, and finally loss of cytoplasmic content. Also, SMase treatment resulted in ceramide-associated alterations in membrane-cytoskeleton interactions and membrane organization, including microdomain formation. Furthermore, we observed increases in membrane fragility, vesiculation and invagination, and large protein clusters. These changes were associated with enhanced erythrocyte retention in a spleen-mimicking model. Erythrocyte storage under blood bank conditions and during physiological aging increased the sensitivity to SMase. A low SMase activity already induced morphological and structural changes, demonstrating the potential of SMase to disturb erythrocyte homeostasis. Our analyses provide a comprehensive picture in which ceramide-induced changes in membrane microdomain organization disrupt the membrane-cytoskeleton interaction and membrane integrity, leading to vesiculation, reduced deformability, and finally loss of erythrocyte content. Understanding these processes is highly relevant for understanding anemia during chronic inflammation, especially in critically ill patients receiving blood transfusions.

Hypoxic exercise training causes erythrocyte senescence and rheological dysfunction by depressed Gardos channel activity.

PubMed

Mao, Tso-Yen; Fu, Li-Lan; Wang, Jong-Shyan

2011-08-01

Despite enhancing cardiopulmonary and muscular fitness, the effect of hypoxic exercise training (HE) on hemorheological regulation remains unclear. This study investigates how HE modulates erythrocyte rheological properties and further explores the underlying mechanisms in the hemorheological alterations. Twenty-four sedentary males were randomly divided into hypoxic (HE; n = 12) and normoxic (NE; n = 12) exercise training groups. The subjects were trained on 60% of maximum work rate under 15% (HE) or 21% (NE) O(2) condition for 30 min daily, 5 days weekly for 5 wk. The results demonstrated that HE 1) downregulated CD47 and CD147 expressions on erythrocytes, 2) decreased actin and spectrin contents in erythrocytes, 3) reduced erythrocyte deformability under shear flow, and 4) diminished erythrocyte volume changed by hypotonic stress. Treatment of erythrocytes with H(2)O(2) that mimicked in vivo prooxidative status resulted in the cell shrinkage, rigidity, and phosphatidylserine exposure, whereas HE enhanced the eryptotic responses to H(2)O(2). However, HE decreased the degrees of clotrimazole to blunt ionomycin-induced shrinkage, rigidity, and cytoskeleton breakdown of erythrocytes, referred to as Gardos effects. Reduced erythrocyte deformability by H(2)O(2) was inversely related to the erythrocyte Gardos effect on the rheological function. Conversely, NE intervention did not significantly change resting and exercise erythrocyte rheological properties. Therefore, we conclude that HE rather than NE reduces erythrocyte deformability and volume regulation, accompanied by an increase in the eryptotic response to oxidative stress. Simultaneously, this intervention depresses Gardos channel-modulated erythrocyte rheological functions. Results of this study provide further insight into erythrocyte senescence induced by HE.

A sperm-agglutinating lectin from seeds of Jack fruit (Artocarpus heterophyllus).

PubMed

Namjuntra, P; Muanwongyathi, P; Chulavatnatol, M

1985-04-30

A lectin specific for N-acetylgalactosamine was isolated from seed extract of Jack fruit (Artocarpus heterophyllus) by ammonium sulfate precipitation, followed by affinity chromatography on a Affigel-galactosamine-agarose column. The lectin possessed agglutinating activities for human and rat sperm as well as human red blood cells. It was found to have Mr = 62,000 consisting of two dissimilar subunits of Mr = 18,000 and 13,000. It also cross-reacted with an antibody against the lectin of Osage Orange (Maclura pomifera).

Erythrocyte antioxidant enzyme activities and lipid peroxidation in the erythrocyte membrane of stainless-steel welders exposed to welding fumes and gases.

PubMed

Imamoglu, Nalan; Yerer, Mükerrem-Betül; Donmez-Altuntas, Hamiyet; Saraymen, Recep

2008-03-01

The erythrocyte antioxidant system (superoxide dismutase, SOD; catalase, CAT) and lipid peroxidation (malondialdehyde, MDA) in the erythrocyte membrane were studied in workers continously exposed to welding fumes and gases, which are thought to be oxidant pollutants. Thirty-five welders using the manual metal arc method on stainless steel and 30 controls were studied. Plasma chromium (Cr), manganese (Mn), and cupper (Cu) levels were determined by atomic absorption spectrophotometer (AAS). The erythrocyte antioxidant system activity and lipid peroxidation in the erythrocyte membrane were evaluated. Not only the possible effects of welding fumes but also the effects of smoking were considered. The plasma concentrations of Cr, Mn, and Cu for the exposed welders were significantly higher compared to the control subjects (p<0.001, p<0.01, p<0.001, respectively,). The erythrocyte CAT (p<0.05) and SOD (p<0.05) enzyme activities were significantly higher in the welders but there were not any significant changes in the MDA levels which reflect the lipid peroxidation in the erythrocyte membrane (p>0.05). Smoking has increased the SOD activity in both controls (p<0.05) and welders (p<0.01) and increased the CAT activity in control subjects (p<0.05). Moreover, regardless of smoking, there were some significant correlations between the duration of the exposure to welding fumes and antioxidant defence system (SOD: p<0.05; CAT: p<0.05). The synergistic effects of smoking and other risk factors (welding fumes and gases), which had been shown previously by some clinical data should also be taken into account. As a consequence, the welders should be warned and informed of the synergistic effects of smoking on the adverse effect of welding fumes and gases.

Outbreak of uncommon O4 non-agglutinating Salmonella typhimurium linked to minced pork, Saxony-Anhalt, Germany, January to April 2013.

PubMed

Alt, Katja; Simon, Sandra; Helmeke, Carina; Kohlstock, Claudia; Prager, Rita; Tietze, Erhard; Rabsch, Wolfgang; Karagiannis, Ioannis; Werber, Dirk; Frank, Christina; Fruth, Angelika

2015-01-01

In January 2013, the National Reference Centre for Salmonella (NRC) detected a salmonellosis cluster in Saxony-Anhalt, Germany, caused by uncommon O4 non-agglutinating, monophasic Salmonella (S.) Typhimurium DT193. Circulating predominant monophasic S. Typhimurium DT193 clones typically display resistance phenotype ASSuT. We investigated common exposures to control the outbreak, and conducted microbiological investigations to assess the strains' phenotype. We conducted a case-control study defining cases as persons living or working in Saxony-Anhalt diagnosed with the O4 non-agglutinating strain between January and March 2013. We selected two controls contemporarily reported with norovirus infection, frequency-matched on residence and age group, per case. We interviewed regarding food consumption, especially pork and its place of purchase. We calculated odds ratios (ORs) with 95% confidence intervals (95% CI) using logistic regression. The NRC investigated human and food isolates by PCR, SDS-PAGE, MLST, PFGE, MLVA and susceptibility testing. Altogether, 68 O4 non-agglutinating human isolates were confirmed between January and April 2013. Of those, 61 were assigned to the outbreak (median age 57 years, 44% female); 83% cases ≥ 60 years were hospitalized. Eating raw minced pork from butcheries within 3 days was associated with disease (31 cases, 28 controls; OR adjusted for sex: 3.6; 95% CI: 1.0-13). Phage type DT193 and MLST ST34 were assigned, and isolates' lipopolysaccharide (LPS) matched control strains. Isolates linked to Saxony-Anhalt exhibited PFGE type 5. ASSuT- and ACSSuT phenotype proportions were 34 and 39% respectively; 54% were resistant to chloramphenicol. Three pork isolates matched the outbreak strain. Raw minced pork was the most likely infection vehicle in this first reported outbreak caused by O4 non-agglutinating, mostly chloramphenicol-resistant S. Typhimurium DT193. High hospitalization proportions demand awareness on the risk of consumption

Dog Erythrocyte Antigen 1 (DEA 1): Mode of Inheritance and Initial Characterization

PubMed Central

Polak, Klaudia; Acierno, Michelle; Raj, Karthik; Mizukami, Keijiro; Siegel, Don L.; Giger, Urs

2015-01-01

Background The Dog Erythrocyte Antigen (DEA) 1 blood group system remains poorly defined. Objectives The purpose of the study was to determine the DEA 1 mode of inheritance and to characterize the DEA 1 antigen and alloantibodies. Animals Canine research colony families, clinic canine patients, and DEA 1.2+ blood bank dogs were studied. Methods Canine blood was typed by flow cytometry and immunochromatographic strips using anti-DEA 1 monoclonal antibodies. Gel column experiments with polyclonal and immunoblotting with monoclonal anti-DEA 1 antibodies were performed to analyze select samples. Cross-reactivity of human typing reagents against canine RBCs and one monoclonal anti-DEA 1 antibody against human RBC panels was assessed. Results Typing of 12 families comprising 144 dogs indicated an autosomal dominant inheritance with ≥4 alleles: DEA 1− (0) and DEA 1+ weak (1+), intermediate (2+) and strong (3+ and 4+). Samples from 6 dogs previously typed as DEA 1.2+ were typed as DEA 1+ or DEA 1− using monoclonal antibodies. Human typing reagents produced varied reactions in tube agglutination experiments against DEA 1+ and DEA 1− RBCs. Polypeptide bands were not detected on immunoblots using a monoclonal anti-DEA 1 antibody, therefore the anti-DEA 1 antibody may be specific for conformational epitopes lost during denaturation. Conclusions The autosomal dominant inheritance of DEA 1 with ≥4 alleles indicates a complex blood group system; the antigenicity of each DEA 1+ type will need to be determined. The biochemical nature of the DEA 1 antigen(s) appears different from human blood group systems tested. PMID:26291052

Stimulation of ceramide formation and suicidal erythrocyte death by vitamin K(3) (menadione).

PubMed

Qadri, Syed M; Eberhard, Matthias; Mahmud, Hasan; Föller, Michael; Lang, Florian

2009-11-25

Vitamin K(3) is an essential micronutrient required for the activation of coagulation factors and thus hemostasis. Administration of vitamin K(3) analogues may cause anemia, which at least in theory could be due to stimulation of suicidal erythrocyte death or eryptosis characterized by cell shrinkage and phospholipid scrambling of the erythrocyte cell membrane leading to exposure of phosphatidylserine at the erythrocyte surface. Eryptosis is triggered by an increase in the cytosolic Ca(2+) activity, by ceramide and by energy depletion (decrease of cytosolic ATP). The present experiments explored, whether vitamin K(3) may influence eryptosis. Hemolysis was estimated from the supernatant hemoglobin concentration, phosphatidylserine-exposing erythrocytes from annexin V-binding in fluorescence-activated cell sorter (FACS) analysis, erythrocyte volume from forward scatter in FACS analysis, ceramide formation from binding of fluorescent antibodies, and erythrocyte ATP content from a luciferin-luciferase assay. As a result, vitamin K(3) (> or =1microM) caused lysis of an only small fraction of erythrocytes, but significantly increased ceramide formation, significantly increased the percentage of annexin V-binding erythrocytes, significantly decreased forward scatter and, at higher concentrations, significantly decreased the cellular ATP content. In conclusion, vitamin K(3) stimulates suicidal erythrocyte death, an effect at least partially due to ceramide formation and ATP depletion.

Physiological variations in levels of 2,3-diphosphoglycerate in horse erythrocytes.

PubMed

Lewis, I M; McLan, J G

1975-03-01

The levels of 2,3-diphosphoglycerate (2,3-DPG), which affects the transport of oxygen by haemoglobin, were examined in horse blood. Resting levels of erythrocyte 2,3-DPG were established in thoroughbred horses, and levels of 2,3-DPG together with haemoglobin levels, were examined in a variety of conditions. A negative correlation was observed between erythrocyte 2,3-DPG and haemoglobin levels. Mares had higher erythrocyte 2,3-DPG levels was observed during training, and this variation may have a significant effect on haemoglobin oxygen transport. Erythrocyte 2,3-DPG levels were not affected by age or exercise.

Determination of immune status in dogs against CPV-2 by recombinant protein based latex agglutination test.

PubMed

Thomas, Jobin; Singh, Mithilesh; Goswami, T K; Glora, Philma; Chakravarti, Soumendu; Chander, Vishal; Upmanyu, Vikramaditya; Verma, Suman; Sharma, Chhavi; Mahendran, K

2017-09-01

Canine parvoviral enteritis is a highly contagious viral illness caused by canine parvovirus-2 (CPV-2) which affects puppies of mainly 6-20 weeks of age. Vaccination is pivotal in preventing and controlling CPV-2 infection. Determination of antibody status is a critical determinant for successful vaccination. The hemagglutination inhibition (HI) test is 'gold standard' test for quantification of antibodies specific to CPV-2, although the execution of this test is not feasible under field conditions. The present study was undertaken to develop a point of care testing to determine immune status prior to CPV-2 vaccination or to detect seroconversion in immunized dogs by latex agglutination test (LAT) using recombinant antigen. Truncated portion of VP2 protein (tVP2) of CPV-2 was selected on the basis of antigenic indices, overexpressed the recombinant protein in E. coli system and was subsequently used in development of LAT. A total of 59 serum samples obtained from vaccinated (n = 54) and healthy unvaccinated (n = 5) dogs were tested. The positivity was observed in 85% (46/54) of these dogs with varying agglutination pattern. The overall sensitivity and specificity of latex agglutination test in comparison to HI test was recorded as 90% and 88% respectively with an agreement value of 90% (CI = 95%). Copyright © 2017 International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

Mortality in rabbits transported for slaughter.

PubMed

Voslarova, Eva; Vecerek, Vladimir; Bedanova, Iveta; Vecerkova, Lenka

2018-06-01

During transport rabbits may be exposed to various stressors which can compromise both their welfare and meat quality. Mortality related to the commercial transport of rabbits for slaughter was analyzed in the Czech Republic in the period from 2009 to 2016. The overall transport-related mortality of rabbits was 0.19%. Transport distance was found to have an impact on rabbit mortality; significantly (p < .001) greater losses were found in rabbits transported over longer distances. Mortality rates ranged from 0.02% in rabbits transported over distances of less than 50 km to 0.29% in rabbits transported over distances exceeding 400 km. A significantly (p < .001) increased risk was also associated with shipments in which 500 and more rabbits were delivered per batch. No effect of season was found. Our results show that rabbits can be transported within a wide range of temperatures (from -5 to 19.9°C) with no negative impact on mortality in transit. However, journeys carried out at temperatures below -5°C and above 20°C were associated with increased death losses (0.17% and 0.15%, respectively). © 2018 Japanese Society of Animal Science.

Desickling of Sickle Cell Erythrocytes by Pulsed RF Fields.

DTIC Science & Technology

1986-09-16

spectrophotometery. Field induced menbrane potential which causes the L partyl breakdown of the memrbrane and the formation of pores was calculated... plasma . Fig.5 shows the photographs of sickled and desickled SS erythrocytes which are suspended in Hank’s solution. As shown, desickled erythrocytes

The effect of phosphate loading on erythrocyte 2,3-bisphosphoglycerate levels.

PubMed

Bremner, Kyla; Bubb, William A; Kemp, Graham J; Trenell, Michael I; Thompson, Campbell H

2002-09-01

Phosphate supplementation has been used in an effort to enhance athletic performance by increasing erythrocyte 2,3-bisphosphoglycerate levels ([2,3-BPG]) and hence improve oxygen offloading from haemoglobin. Claimed effects of phosphate loading upon both exercise performance and erythrocyte [2,3-BPG] are inconsistent, and the basis of any change in [2,3-BPG] is unknown. We analysed plasma inorganic phosphate concentration ([P(i)]) and erythrocyte [P(i)] and [2,3-BPG] in venous blood samples from 12 healthy subjects. We re-examined a subset of five of these subjects after 7 days of phosphate loading. There were significant positive correlations between plasma [P(i)] and erythrocyte [P(i)] (r(2)=0.51, p=0.009) and between erythrocyte [P(i)] and [2,3-BPG] (r(2)=0.68, p<0.001). Following phosphate loading, there was a 30% increase in plasma [P(i)] (1.02+/-0.22 to 1.29+/-0.15 mmol/l (mean+/-S.D.), p=0.03) and a 25% increase in erythrocyte [2,3-BPG] (6.77+/-1.12 to 9.11+/-1.87 mmol/l cells, p=0.03). There is no relation between [2,3-BPG] and plasma [P(i)]. Phosphate loading increases both plasma and erythrocyte phosphate pools and the rise in [2,3-BPG] is probably a consequence of the rise in cell [P(i)].

Targeting malaria parasite proteins to the erythrocyte.

PubMed

Templeton, Thomas J; Deitsch, Kirk W

2005-09-01

The intraerythrocytic stages of the protozoan parasite Plasmodium falciparum reside within a parasitophorous vacuole (PV) and set up unique "extraparasite, intraerythrocyte" protein-trafficking pathways that target parasite-encoded proteins to the erythrocyte cytoplasm and cell surface. Two recent articles report the identification of trafficking motifs that regulate the transport of parasite-encoded proteins across the PV. These articles greatly aid the annotation of the parasite "secretome" catalog of proteins that are targeted to the erythrocyte cytoplasm or cell membrane.

Origins and function of 3-ribosylurate in bovid erythrocytes.

PubMed

Davids, V; Blackhurst, D M; Katz, A A; Harley, E H

2012-06-01

3-Ribosylurate is a dominant feature on high performance liquid chromatography (HPLC) profiles of acid extracts of erythrocytes from cows and buffalo, but is HPLC-undetectable in acid extracts of erythrocytes from all other species examined to date. Various aspects of this unique low molecular weight substance remain unexplored since it was first identified. In this study, the mutation(s) responsible for the appearance of ribosylurate in these cells is shown to be specific to members of both tribes of the Bovinae subfamily (Bovidae family), being detectable in the erythrocytes of both the cow and the buffalo (Bovini tribe) as well as in the kudu (Strepsicerotini tribe), but not in representative species from the other subfamilies of the Bovidae family. More specifically, expression of the mutation(s) seems to be restricted to the erythrocyte lineage of these species, ribosylurate being undetectable in cow white blood cells and primary cultures of fibroblasts. Novel evidence is presented that ribosylurate has antioxidant activity. Accumulation of high levels specifically within the haemoglobin-rich milieu of circulating erythrocytes may serve to protect perfused tissues by removing pathophysiological levels of hydrogen peroxide from plasma. Maintenance of ribosylurate levels may be important in conditions associated with oxidative stress in Bovinae. Copyright © 2011 Elsevier Ltd. All rights reserved.

Life cycle-dependent cytoskeletal modifications in Plasmodium falciparum infected erythrocytes.

PubMed

Shi, Hui; Liu, Zhuo; Li, Ang; Yin, Jing; Chong, Alvin G L; Tan, Kevin S W; Zhang, Yong; Lim, Chwee Teck

2013-01-01

Plasmodium falciparum infection of human erythrocytes is known to result in the modification of the host cell cytoskeleton by parasite-coded proteins. However, such modifications and corresponding implications in malaria pathogenesis have not been fully explored. Here, we probed the gradual modification of infected erythrocyte cytoskeleton with advancing stages of infection using atomic force microscopy (AFM). We reported a novel strategy to derive accurate and quantitative information on the knob structures and their connections with the spectrin network by performing AFM-based imaging analysis of the cytoplasmic surface of infected erythrocytes. Significant changes on the red cell cytoskeleton were observed from the expansion of spectrin network mesh size, extension of spectrin tetramers and the decrease of spectrin abundance with advancing stages of infection. The spectrin network appeared to aggregate around knobs but also appeared sparser at non-knob areas as the parasite matured. This dramatic modification of the erythrocyte skeleton during the advancing stage of malaria infection could contribute to the loss of deformability of the infected erythrocyte.

Glycomics-based analysis of chicken red blood cells provides insight into the selectivity of the viral agglutination assay.

PubMed

Aich, Udayanath; Beckley, Nia; Shriver, Zachary; Raman, Rahul; Viswanathan, Karthik; Hobbie, Sven; Sasisekharan, Ram

2011-05-01

Agglutination of red blood cells (RBCs), including chicken RBCs (cRBCs), has been used extensively to estimate viral titer, to screen glycan-receptor binding preference, and to assess the protective response of vaccines. Although this assay enjoys widespread use, some virus strains do not agglutinate RBCs. To address these underlying issues and to increase the usefulness of cRBCs as tools for studying viruses, such as influenza, we analyzed the cell surface N-glycans of cRBCs. On the basis of the results obtained from complementary analytical strategies, including MS, 1D and 2D-NMR spectroscopy, exoglycosidase digestions, and HPLC profiling, we report the major glycan structures present on cRBCs. By comparing the glycan structures of cBRCs with those of representative human upper respiratory cells, we offer a possible explanation for the fact that certain influenza strains do not agglutinate cRBCs, using specific human-adapted influenza hemagglutinins as examples. Finally, recent understanding of the role of various glycan structures in high affinity binding to influenza hemagglutinins provides context to our findings. These results illustrate that the field of glycomics can provide important information with respect to the experimental systems used to characterize, detect and study viruses. © 2011 The Authors Journal compilation © 2011 FEBS.

A deep-sea agglutinated foraminifer tube constructed with planktonic foraminifer shells of a single species

NASA Astrophysics Data System (ADS)

Pearson, Paul N.; Expedition 363 Shipboard Scientific Party, IODP

2018-01-01

Agglutinated foraminifera are marine protists that show apparently complex behaviour in constructing their shells, involving selecting suitable sedimentary grains from their environment, manipulating them in three dimensions, and cementing them precisely into position. Here we illustrate a striking and previously undescribed example of complex organisation in fragments of a tube-like foraminifer (questionably assigned to Rhabdammina) from 1466 m water depth on the northwest Australian margin. The tube is constructed from well-cemented siliciclastic grains which form a matrix into which hundreds of planktonic foraminifer shells are regularly spaced in apparently helical bands. These shells are of a single species, Turborotalita clarkei, which has been selected to the exclusion of all other bioclasts. The majority of shells are set horizontally in the matrix with the umbilical side upward. This mode of construction, as is the case with other agglutinated tests, seems to require either an extraordinarily selective trial-and-error process at the site of cementation or an active sensory and decision-making system within the cell.

Serodiagnosis of bovine leptospirosis by IgG-enzyme-linked immunosorbent assay and latex agglutination test.

PubMed

Senthilkumar, T M A; Subathra, M; Ramadass, P; Ramaswamy, V

2010-02-01

The efficacy of a recombinant leptospiral outer membrane protein LipL41 as an antigen for conducting IgG-Enzyme linked immunosorbent assay (ELISA) and latex agglutination test (LAT) for serodiagnosis of bovine leptospirosis was evaluated. The recombinant LipL41 antigen developed and used for detecting the antibodies was specific in detection of the pathogenic serovars of Leptospira, as the expression of the LipL41 antigen is restricted only to pathogenic leptospires. A total of 430 bovine serum samples were subjected to IgG-ELISA and LAT, and the sensitivity and specificity were assessed in comparison with microscopic agglutination test (MAT). The sensitivity and specificity of IgG-ELISA and LAT were 86.84% and 93.16%, and 95.42% and 98.33% respectively. Both the tests are found to be sensitive, specific and concurred with the standard MAT. The study concluded that the rLipL41 protein could be used as a potential diagnostic antigen in different assay formats for bovine leptospirosis.

Chlorpyrifos and lambda cyhalothrin-induced oxidative stress in human erythrocytes.

PubMed

Deeba, Farah; Raza, Irum; Muhammad, Noor; Rahman, Hazir; Ur Rehman, Zia; Azizullah, Azizullah; Khattak, Baharullah; Ullah, Farman; Daud, M K

2017-04-01

Pesticides are one of the most potentially harmful chemicals introduced into the environment, and their adverse impacts on non-target organisms can be significant. The present study was conducted to shed light on effects of locally used insecticides chlorpyrifos (CPF) and lambda cyhalothrin (LCT) on oxidative stress biomarkers in human erythrocytes. The activity of catalase (CAT), superoxide dismutase (SOD), and protein contents as well as the levels of malondialdehyde (MDA) and osmotic fragility (OF) were measured in human erythrocytes exposed to CPF at concentrations of 0, 100, 500, 1000, and 2000 ppm and LCT at concentrations of 0, 100, 300, 600, and 800 ppm for 1 h and 3 h at 37°C. MDA levels and OF of erythrocytes were significantly higher in erythrocytes incubated with CPF and LCT at increasing concentrations of both insecticides and increased incubation time. However, erythrocyte CAT and SOD activities were decreased at all concentrations of CPF and LCT tested. Protein oxidation products were decreased at lower doses of CPF (100 and 500 ppm); at higher doses (1000 and 2000 ppm), total protein content was increased compared with control. In contrast LCT was associated with decreased in protein contents at all the concentrations. These results clearly demonstrated that CPF and LCT can induce oxidative stress in human erythrocytes ( in vitro).

Functional consequences of sphingomyelinase-induced changes in erythrocyte membrane structure

PubMed Central

Dinkla, S; Wessels, K; Verdurmen, W P R; Tomelleri, C; Cluitmans, J C A; Fransen, J; Fuchs, B; Schiller, J; Joosten, I; Brock, R; Bosman, G J C G M

2012-01-01

Inflammation enhances the secretion of sphingomyelinases (SMases). SMases catalyze the hydrolysis of sphingomyelin into phosphocholine and ceramide. In erythrocytes, ceramide formation leads to exposure of the removal signal phosphatidylserine (PS), creating a potential link between SMase activity and anemia of inflammation. Therefore, we studied the effects of SMase on various pathophysiologically relevant parameters of erythrocyte homeostasis. Time-lapse confocal microscopy revealed a SMase-induced transition from the discoid to a spherical shape, followed by PS exposure, and finally loss of cytoplasmic content. Also, SMase treatment resulted in ceramide-associated alterations in membrane–cytoskeleton interactions and membrane organization, including microdomain formation. Furthermore, we observed increases in membrane fragility, vesiculation and invagination, and large protein clusters. These changes were associated with enhanced erythrocyte retention in a spleen-mimicking model. Erythrocyte storage under blood bank conditions and during physiological aging increased the sensitivity to SMase. A low SMase activity already induced morphological and structural changes, demonstrating the potential of SMase to disturb erythrocyte homeostasis. Our analyses provide a comprehensive picture in which ceramide-induced changes in membrane microdomain organization disrupt the membrane–cytoskeleton interaction and membrane integrity, leading to vesiculation, reduced deformability, and finally loss of erythrocyte content. Understanding these processes is highly relevant for understanding anemia during chronic inflammation, especially in critically ill patients receiving blood transfusions. PMID:23076218

Serotype, hemolysin production, and adherence characteristics of strains of Escherichia coli causing urinary tract infection in dogs.

PubMed

Senior, D F; deMan, P; Svanborg, C

1992-04-01

Virulence factors were studied in 82 strains of Escherichia coli isolated from the urine of dogs with urinary tract infections. The most frequently expressed O antigens were 2, 4, 6, 25, and 22/83. Most strains were K nontypeable. Mannose-sensitive hemagglutination (MSH) with canine erythrocytes was observed in 71 strains and mannose-resistant hemagglutination (MRH) was observed in 32 strains. Strains that caused MSH of erythrocytes from dogs also caused MSH of erythrocytes from guinea pigs. Most strains that caused MRH of human A1P1 erythrocytes also reacted with erythrocytes of dogs. Of 22 strains (27%) that agglutinated human A1P1 erythrocytes, but not A1p erythrocytes, 17 (77%) had specificity for globo A, but did not react with the galactose alpha 1----4galactose beta disaccharide receptor. The remaining 5 strains and 2 others that simultaneously expressed an X adhesin agglutinated galactose alpha 1----4galactose beta-coated latex beads. Bacterial adherence to canine uroepithelial cells from the bladder was most often observed in strains expressing MSH, less often observed in strains expressing MRH, and least often observed in strains that failed to induce hemagglutination. Adherence of MSH strains to canine uroepithelial cells was inhibited by alpha-methyl-D-mannoside. As a group, MRH strains expressing globo-A- and galactose alpha 1----4galactose beta-specific adhesins did not have strong adherence. Strains of E coli isolated from dogs with urinary tract infections most commonly expressed type-1 fimbriae, and the main mechanism of in vitro adherence to canine uroepithelial cells involved a mannose-sensitive mechanism. Overrepresentation of globo-A-specific adhesins did not appear to be related to adherence of canine uroepithelial cells.

Stimulation of suicidal erythrocyte death by sulforaphane.

PubMed

Alzoubi, Kousi; Calabrò, Salvatrice; Faggio, Caterina; Lang, Florian

2015-03-01

Sulforaphane, an isothiocyanate from cruciferous vegetable, counteracts malignancy. The effect is at least in part due to the stimulation of suicidal death or apoptosis of tumour cells. Mechanisms invoked in sulforaphane-induced apoptosis include mitochondrial depolarization and altered gene expression. Despite the lack of mitochondria and nuclei, erythrocytes may, similar to apoptosis of nucleated cells, enter eryptosis, a suicidal cell death characterized by cell shrinkage and phosphatidylserine translocation to the erythrocyte surface. Stimulators of eryptosis include increase of cytosolic Ca(2+)-activity ([Ca(2+)]i). This study explored whether sulforaphane stimulates eryptosis. Cell volume was estimated from forward scatter, phosphatidylserine exposure at the cell surface from annexin V binding and [Ca(2+)]i from Fluo-3 fluorescence. A 48-hr treatment of human erythrocytes with sulforaphane (50-100 μM) significantly decreased forward scatter, significantly increased the percentage of annexin V binding cells and significantly increased [Ca(2+)]i. The effect of sulforaphane (100 μM) on annexin V binding was significantly blunted but not abrogated by the removal of extracellular Ca(2+). Sulforaphane (100 μM) significantly increased ceramide formation. In conclusion, sulforaphane stimulates suicidal erythrocyte death or eryptosis, an effect at least partially, but not exclusively, due to the stimulation of Ca(2+) entry and ceramide formation. © 2014 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

Adenosine signaling in normal and sickle erythrocytes and beyond.

PubMed

Zhang, Yujin; Xia, Yang

2012-08-01

Sickle cell disease (SCD) is a debilitating hemolytic genetic disorder with high morbidity and mortality affecting millions of individuals worldwide. Although SCD was discovered more than a century ago, no effective mechanism-based prevention and treatment are available due to poorly understood molecular basis of sickling, the fundamental pathogenic process of the disease. SCD patients constantly face hypoxia. One of the best-known signaling molecules to be induced under hypoxic conditions is adenosine. Recent studies demonstrate that hypoxia-mediated elevated adenosine signaling plays an important role in normal erythrocyte physiology. In contrast, elevated adenosine signaling contributes to sickling and multiple life threatening complications including tissue damage, pulmonary dysfunction and priapism. Here, we summarize recent research on the role of adenosine signaling in normal and sickle erythrocytes, progression of the disease and therapeutic implications. In normal erythrocytes, both genetic and pharmacological studies demonstrate that adenosine can enhance 2,3-bisphosphoglycerate (2,3-BPG) production via A(2B) receptor (ADORA2B) activation, suggesting that elevated adenosine has an unrecognized role in normal erythrocytes to promote O(2) release and prevent acute ischemic tissue injury. However, in sickle erythrocytes, the beneficial role of excessive adenosine-mediated 2,3-BPG induction becomes detrimental by promoting deoxygenation, polymerization of sickle hemoglobin and subsequent sickling. Additionally, adenosine signaling via the A(2A) receptor (ADORA2A) on invariant natural killer T (iNKT) cells inhibits iNKT cell activation and attenuates pulmonary dysfunction in SCD mice. Finally, elevated adenosine coupled with ADORA2BR activation is responsible for priapism, a dangerous complication seen in SCD. Overall, the research reviewed here reveals a differential role of elevated adenosine in normal erythrocytes, sickle erythrocytes, iNK cells and

Simple Additive Weighting to Diagnose Rabbit Disease

NASA Astrophysics Data System (ADS)

Ramadiani; Marissa, Dyna; Jundillah, Muhammad Labib; Azainil; Hatta, Heliza Rahmania

2018-02-01

Rabbit is one of the many pets maintained by the general public in Indonesia. Like other pet, rabbits are also susceptible to various diseases. Society in general does not understand correctly the type of rabbit disease and the way of treatment. To help care for sick rabbits it is necessary a decision support system recommendation diagnosis of rabbit disease. The purpose of this research is to make the application of rabbit disease diagnosis system so that can help user in taking care of rabbit. This application diagnoses the disease by tracing the symptoms and calculating the recommendation of the disease using Simple Additive Weighting method. This research produces a web-based decision support system that is used to help rabbit breeders and the general public.

VENEREAL SPIROCHETOSIS IN AMERICAN RABBITS

PubMed Central

Noguchi, Hideyo

1922-01-01

Of 50 rabbits, otherwise regarded as normal, three adult females and two adult males (10 per cent) have been found to have in their genitoperineal region certain papulosquamous, often ulcerating, lesions. A recently purchased group of twenty rabbits contained six females (30 per cent) with similar lesions. This condition runs a chronic course and is characterized by the presence of a spiral organism closely resembling Treponema pallidum. The rabbit spirochete has the same morphological features as Treponema pallidum; it is possibly a trifle thicker and longer than the average pallidum. Long specimens measuring 30 µ are frequently encountered, and they show a tendency to form loosely entangled knots. A stellate arrangement of several organisms in a mass is frequently observed. In the lesion of one rabbit there were two types of spirochete, one of the variety just described, the other a somewhat coarser organism, closely resembling Treponema calligyrum found in a human condyloma, but a trifle thinner and longer. This organism is perhaps merely a variant type of the rabbit spirochete. The histological reactions are similar to, but considerably less cellular, than those occurring in typical primary syphilitic lesions. There is a marked hyperkeratosis and interpapillary infiltration not observed in scrotal chancre. The disease is transmissible to normal rabbits, in which the usual papular lesions can be readily reproduced in the genitoperineal region. In the first passages the incubation period varied from 20 to 88 days; subsequently one of the strains produced a lesion in 20 days on the second, and in 5 days on the third passage. No typical orchitis or keratitis was produced in the rabbits of the present series, although in one of the original rabbits (No. 4) scaly, papular lesions have developed on the nose, lips, eyelid, and paws. Monkeys (Macacus rhesus) failed to show any lesions within a period of 4 months after inoculation. In one instance transmission was

Erythrocyte deformability and nitric oxide mobilization under pannexin-1 and PKC dependence.

PubMed

Silva-Herdade, A S; Freitas, T; Almeida, J Pedro; Saldanha, C

2015-01-01

The erythrocyte adenosine triphosphate (ATP) is utilised for protein phosphorylation and exported through the pannexin 1 hemichannel (Px1) in the microcirculation. The physiological stimuli for ATP release are dependent of blood shear rate level and of the tissue oxygen content. The deoxygenated and oxygenated states of haemoglobin are respectively bound and unbound to N terminal domain of the protein band 3 of the erythrocyte membrane in dependence of its degree of phosphorylation. The protein tyrosine kinase (PTK) and protein tyrosine phosphatase (PTP) contribute to the phosphorylation degree of band 3 and are modulated by protein kinase C (PKC). Chelerythrine (Che) is a competitive inhibitor of ATP for PKC and a negative modulator of erythrocyte deformability. The aim of this study was to assess the mobilization of nitric oxide (NO) in erythrocyte in absence and presence of Che and Px1 inhibitor (carbenoxolone). Erythrocyte deformability was evaluated in presence of carbenoxolone (Carb). Regarding the effects observed in the erythrocyte by presence of Che or Carb, the values of efflux of NO and the concentration of nitrosogluthatione are similar and with no changes in relation to their absence. Px1inhibition by Carb 10 μM ameliorates the erythrocyte deformability at a shear force of 0.6 and 1.2 Pa. The PKC inhibitor shows similar effects to the Carb on the mobilization of nitric oxide in erythrocyte. The blockage of ATP release by Carb from erythrocytes suggests a possible benefit to develop in ischemia reperfusion or in inflammatory response where will be needed to rescue the excess of NO present and ameliorate the red blood cell deformability at low shear rates.

Tropomyosin modulates erythrocyte membrane stability

PubMed Central

An, Xiuli; Salomao, Marcela; Guo, Xinhua; Gratzer, Walter; Mohandas, Narla

2007-01-01

The ternary complex of spectrin, actin, and 4.1R (human erythrocyte protein 4.1) defines the nodes of the erythrocyte membrane skeletal network and is inseparable from membrane stability under mechanical stress. These junctions also contain tropomyosin (TM) and the other actin-binding proteins, adducin, protein 4.9, tropomodulin, and a small proportion of capZ, the functions of which are poorly defined. Here, we have examined the consequences of selective elimination of TM from the membrane. We have shown that the mechanical stability of the membranes of resealed ghosts devoid of TM is grossly, but reversibly, impaired. That the decreased membrane stability of TM-depleted membranes is the result of destabilization of the ternary complex of the network junctions is demonstrated by the strongly facilitated entry into the junctions in situ of a β-spectrin peptide, containing the actin- and 4.1R-binding sites, after extraction of the TM. The stabilizing effect of TM is highly specific, in that it is only the endogenous isotype, and not the slightly longer muscle TM that can bind to the depleted membranes and restore their mechanical stability. These findings have enabled us identify a function for TM in elevating the mechanical stability of erythrocyte membranes by stabilizing the spectrin-actin-4.1R junctional complex. PMID:17008534

Evaluation of Intravascular Hemolysis With Erythrocyte Creatine in Patients With Aortic Stenosis.

PubMed

Sugiura, Tetsuro; Okumiya, Toshika; Kubo, Toru; Takeuchi, Hiroaki; Matsumura, Yoshihisa

2016-07-27

Chronic intravascular hemolysis has been identified in patients with cardiac valve prostheses, but only a few case reports have evaluated intravascular hemolysis in patients with native valvular heart disease. To detect intravascular hemolysis in patients with aortic stenosis, erythrocyte creatine was evaluated with hemodynamic indices obtained by echocardiography.Erythrocyte creatine, a marker of erythrocyte age, was assayed in 30 patients with aortic stenosis and 10 aged matched healthy volunteers. Peak flow velocity of the aortic valve was determined by continuous-wave Doppler echocardiography. Twenty of 30 patients with aortic stenosis had high erythrocyte creatine levels (> 1.8 µmol/g Hb) and erythrocyte creatine was significantly higher as compared with control subjects (1.98 ± 0.49 versus 1.52 ± 0.19 µmol/g Hb, P = 0.007). Peak transvalvular pressure gradient ranged from 46 to 142 mmHg and peak flow velocity ranged from 3.40 to 5.95 m/second. Patients with aortic stenosis had a significantly lower erythrocyte count (387 ± 40 versus 436 ± 42 × 10(4) µL, P = 0.002) and hemoglobin (119 ± 11 versus 135 ± 11 g/L, P < 0.001) as compared with control subjects. Erythrocyte creatine had a fair correlation with peak flow velocity (r = 0.55, P = 0.002).In conclusion, intravascular hemolysis due to destruction of erythrocytes was detected in patients with moderate to severe aortic stenosis and the severity of intravascular hemolysis was related to valvular flow velocity of the aortic valve.

Oxidative Hemolysis of Erythrocytes

ERIC Educational Resources Information Center

Wlodek, Lidia; Kusior, Dorota

2006-01-01

This exercise for students will allow them to simultaneously observe lipid peroxidation and consequent hemolysis of rat erythrocytes and the effect of sodium azide, a catalase inhibitor, on these processes. It will also demonstrate a protective action of antioxidants, the therapeutically used N-acetylcysteine and albumins present in plasma.

[Effects of methomyl on acetylcholinesterase in erythrocyte membrane and various brain areas].

PubMed

Zhao, Fei; Li, Tao; Zhang, Changchun; Xu, Yiping; Xu, Hangong; Shi, Nian

2015-06-01

To study the toxicity of methomyl to acetylcholinesterase (AChE) in different regions. The optimal temperature and time for measurement of AChE activity were determined in vitro. The dose- and time-response relationships of methomyl with AChE activity in human erythrocyte membrane, rat erythrocyte membrane, cortical synapses, cerebellar synapses, hippocampal synapses, and striatal synapses were evaluated. The half maximal inhibitory concentration (IC50) and bimolecular rate constant (K) of methomyl for AChE activity in different regions were calculated, and the type of inhibition of AChE activity by methomyl was determined. AChE achieved the maximum activity at 370 °C, and the optimal time to determine initial reaction velocity was 0-17 min. There were dose- and time-response relationships between methomyl and AChE activity in the erythrocyte membrane and various brain areas. The IC50 value of methomyl for AChE activity in human erythrocyte membrane was higher than that in rat erythrocyte membrane, while the Ki value of methomyl for AChE activity in rat erythrocyte membrane was higher than that in human erythrocyte membrane. Among synapses in various brain areas, the striatum had the highest IC50 value, followed by the cerebellum, cerebral cortex, and hippocampus, while the cerebral cortex had the highest Ki value, followed by the hippocampus, striatum, and cerebellum. Lineweaver-Burk diagram demonstrated that with increasing concentration of methomyl, the maximum reaction velocity (Vmax) of AChE decreased, and the Michaelis constant (Km) remained the same. Methomyl is a reversible non-competitive inhibitor of AChE. AChE of rat erythrocyte membrane is more sensitive to methomyl than that of human erythrocyte membrane; the cerebral cortical synapses have the most sensitive AChE to methomyl among synapses in various brain areas.

An ex vivo study of nitric oxide efflux from human erythrocytes in both genders.

PubMed

Duarte, Catarina; Napoleão, Patrícia; Freitas, Teresa; Saldanha, Carlota

2016-01-01

Acetylcholinesterase (AChE) is located on outer surface of erythrocyte membrane. Gender-related differences in erythrocyte AChE enzyme activity had been verified in young adults. It is also known that binding of acetylcholine (ACh) with AChE on erythrocyte membrane initiates a signal transduction mechanism that stimulates nitric oxide (NO) efflux. This ex vivo study was done to compare the amount of NO efflux obtained from erythrocytes of healthy donors in males and females. We included 66 gender age-matched healthy donors (40-60 years old). We performed quantification of erythrocyte NO efflux from erythrocytes and of the membrane AChE enzyme activity. There are no significant differences in NO efflux from erythrocytes between men and women. Regarding AChE enzyme activity values, in this range of age, no differences between genders were obtained. However, the values of AChE enzyme activity in the third quartile of NO efflux values were significantly higher (p < 0.05) in women than in men. The efflux of NO from erythrocyte of healthy humans did not change with gender. For the same range of values of NO efflux from erythrocytes, in both gender, it was verified higher values of AChE enzyme activity in women.

Adverse reactions in a population of Sydney pet rabbits vaccinated against rabbit calicivirus.

PubMed

Tung, T; Phalen, D; Toribio, J-Alml

2015-11-01

To determine the general clinical presentation and incidence of adverse reactions to Cylap® RCD vaccinations, of a nature serious enough for veterinary attention, in a Sydney population of pet rabbits. A retrospective survey using hospital databases. Nine veterinary hospitals in Sydney participated in a database search for the number of rabbits vaccinated within a 2-year period. The hospitals involved had an identified interest in rabbit medicine and included general, specialist and teaching hospitals. Details of the rabbit, vaccination event and any possible reaction were collected and analysed. Of 933 events recorded in 705 rabbits, 17 (1.8%) adverse reactions were observed. Of the adverse events, local injection site reactions (alopecia, abrasions and scabbing) were most common. Other reactions, including systemic signs of gastrointestinal tract stasis, lethargy and forelimb lameness, were also documented. Overall, rabbits presented for vaccination were mostly male (57.7%) and desexed (71.3%), with an average age of 28.1 months (median 19.0, range 1.4-149.8 months) and an average weight at first vaccination of 2.12 kg (median 2.08 kg, range 0.18-5.6 kg). A significant association between increasing age and decreased incidence of adverse events was demonstrated (P value, 0.038). The benefits of vaccination against RCV outweigh the risks of an adverse reaction occurring. Data from this study show that adverse reactions occur infrequently, are generally mild and self-resolving, and decrease in incidence with increasing age. These results are similar to previous field research on wild rabbit colonies and reports from government and industry. © 2015 Australian Veterinary Association.

Role of aminotransferases in glutamate metabolism of human erythrocytes.

PubMed

Ellinger, James J; Lewis, Ian A; Markley, John L

2011-04-01

Human erythrocytes require a continual supply of glutamate to support glutathione synthesis, but are unable to transport this amino acid across their cell membrane. Consequently, erythrocytes rely on de novo glutamate biosynthesis from α-ketoglutarate and glutamine to maintain intracellular levels of glutamate. Erythrocytic glutamate biosynthesis is catalyzed by three enzymes, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and glutamine aminohydrolase (GA). Although the presence of these enzymes in RBCs has been well documented, the relative contributions of each pathway have not been established. Understanding the relative contributions of each biosynthetic pathway is critical for designing effective therapies for sickle cell disease, hemolytic anemia, pulmonary hypertension, and other glutathione-related disorders. In this study, we use multidimensional (1)H-(13)C nuclear magnetic resonance (NMR) spectroscopy and multiple reaction mode mass spectrometry (MRM-MS) to measure the kinetics of de novo glutamate biosynthesis via AST, ALT, and GA in intact cells and RBC lysates. We show that up to 89% of the erythrocyte glutamate pool can be derived from ALT and that ALT-derived glutamate is subsequently used for glutathione synthesis.

Triggering of Erythrocyte Cell Membrane Scrambling by Emodin.

PubMed

Mischitelli, Morena; Jemaà, Mohamed; Almasry, Mustafa; Faggio, Caterina; Lang, Florian

2016-01-01

The natural anthraquinone derivative emodin (1,3,8-trihydroxy-6-methylanthraquinone) is a component of several Chinese medicinal herbal preparations utilized for more than 2000 years. The substance has been used against diverse disorders including malignancy, inflammation and microbial infection. The substance is effective in part by triggering suicidal death or apoptosis. Similar to apoptosis of nucleated cells erythrocytes may enter suicidal erythrocyte death or eryptosis, characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Signaling involved in the triggering of eryptosis include increase of cytosolic Ca2+ activity ([Ca2+]i), oxidative stress and ceramide. The present study aimed to test, whether emodin induces eryptosis and, if so, to elucidate underlying cellular mechanisms. Phosphatidylserine abundance at the cell surface was estimated from annexin-V-binding, cell volume from forward scatter, [Ca2+]i from Fluo3-fluorescence, ROS formation from DCFDA dependent fluorescence, and ceramide abundance utilizing specific antibodies. Exposure of human erythrocytes for 48 hours to emodin (≥ 10 µM) significantly increased the percentage of annexin-V-binding cells, and at higher concentrations (≥ 50 µM) significantly increased forward scatter. Emodin significantly increased Fluo3-fluorescence (≥ 10 µM), DCFDA fluorescence (75 µM) and ceramide abundance (75 µM). The effect of emodin on annexin-V-binding was significantly blunted but not abolished by removal of extracellular Ca2+. Emodin triggers phospholipid scrambling of the erythrocyte cell membrane, an effect at least in part due to stimulation of Ca2+ entry and paralleled by oxidative stress and ceramide appearance at the erythroctye surface. © 2016 The Author(s) Published by S. Karger AG, Basel.

Stimulation of erythrocyte phosphatidylserine exposure by mercury ions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eisele, Kerstin; Lang, Philipp A.; Kempe, Daniela S.

2006-01-15

The sequelae of mercury intoxication include induction of apoptosis. In nucleated cells, Hg{sup 2+}-induced apoptosis involves mitochondrial damage. The present study has been performed to elucidate effects of Hg{sup 2+} in erythrocytes which lack mitochondria but are able to undergo apoptosis-like alterations of the cell membrane. Previous studies have documented that activation of a Ca{sup 2+}-sensitive erythrocyte scramblase leads to exposure of phosphatidylserine at the erythrocyte surface, a typical feature of apoptotic cells. The erythrocyte scramblase is activated by osmotic shock, oxidative stress and/or energy depletion which increase cytosolic Ca{sup 2+} activity and/or activate a sphingomyelinase leading to formation ofmore » ceramide. Ceramide sensitizes the scramblase to Ca{sup 2+}. The present experiments explored the effect of Hg{sup 2+} ions on erythrocytes. Phosphatidylserine exposure after mercury treatment was estimated from annexin binding as determined in FACS analysis. Exposure to Hg{sup 2+} (1 {mu}M) indeed significantly increased annexin binding from 2.3 {+-} 0.5% (control condition) to 23 {+-} 6% (n = 6). This effect was paralleled by activation of a clotrimazole-sensitive K{sup +}-selective conductance as measured by patch-clamp recordings and by transient cell shrinkage. Further experiments revealed also an increase of ceramide formation by {approx}66% (n = 7) after challenge with mercury (1 {mu}M). In conclusion, mercury ions activate a clotrimazole-sensitive K{sup +}-selective conductance leading to transient cell shrinkage. Moreover, Hg{sup 2+} increases ceramide formation. The observed mechanisms could similarly participate in the triggering of apoptosis in nucleated cells by Hg{sup 2+}.« less

Comparison of three optical methods to study erythrocyte aggregation.

PubMed

Zhao, H; Wang, X; Stoltz, J F

1999-01-01

The aim of this work was to evaluate three optical methods designed to determine erythrocyte aggregation: Erythroaggregometer (EA; Regulest, France), Laser-assisted Optical Rotational Cell Analyzer (LORCA; Mechatronics, Netherlands) and Fully Automatic Erythrocyte Aggregometer (FAEA; Myrenne, GmbH, Germany). Blood samples were taken from fifty donors (26 males and 24 females). The aggregation of normal red blood cell (RBC) and RBCs suspended in three normo- and hyperaggregating suspending media was studied. The results revealed some significant correlations between parameters measured by these instruments, in particular, between the indexes of aggregation of EA and LORCA. Further, RBC aggregation of multiple myeloma patients was also studied and a hyper erythrocyte aggregation state was found by EA and LORCA.

Erythrocyte antioxidant protection of rose hips (Rosa spp.).

PubMed

Widén, C; Ekholm, A; Coleman, M D; Renvert, S; Rumpunen, K

2012-01-01

Rose hips are popular in health promoting products as the fruits contain high content of bioactive compounds. The aim of this study was to investigate whether health benefits are attributable to ascorbic acid, phenols, or other rose-hip-derived compounds. Freeze-dried powder of rose hips was preextracted with metaphosphoric acid and the sample was then sequentially eluted on a C(18) column. The degree of amelioration of oxidative damage was determined in an erythrocyte in vitro bioassay by comparing the effects of a reducing agent on erythrocytes alone or on erythrocytes pretreated with berry extracts. The maximum protection against oxidative stress, 59.4 ± 4.0% (mean ± standard deviation), was achieved when incubating the cells with the first eluted meta-phosphoric extract. Removal of ascorbic acid from this extract increased the protection against oxidative stress to 67.9 ± 1.9%. The protection from the 20% and 100% methanol extracts was 20.8 ± 8.2% and 5.0 ± 3.2%, respectively. Antioxidant uptake was confirmed by measurement of catechin by HPLC-ESI-MS in the 20% methanol extract. The fact that all sequentially eluted extracts studied contributed to protective effects on the erythrocytes indicates that rose hips contain a promising level of clinically relevant antioxidant protection.

[Effects of simulated hypoxia on dielectric properties of mouse erythrocytes].

PubMed

Ma, Qing; Tang, Zhi-Yuan; Wang, Qin-Wen; Zhao, Xin

2008-02-01

To explore the influence of simulated altitude hypoxia on dielectric properties of mouse erythrocytes. Experimental animals were divided into the plain control group(control) and simulated altitude hypoxia group (altitude). The AC impedance of mouse erythrocytes was measured with the Agilent 4294A impedance analyzer, the influence of simulated altitude hypoxia on dielectric properties of mouse erythrocytes was observed by cell dielectric spectroscopy, Cole-Cole plots, loss factor spectrum, loss tangent spectrum, and curve fitting analysis of Cole-Cole equation. After mice were exposed to hypoxia at simulated 5000 m altitude for 4 weeks, permittivity at low frequency (epsilonl) and dielectric increment (deltaepsilon) increased 57% and 59% than that of control group respectively, conductivity at low frequency (kappal) and conductivity at high frequency (kappah) reduced 49% and 11% than that of control group respectively. The simulated altitude hypoxia could arise to increase dielectric capability and depress conductive performance on mouse erythrocytes.

Erythrocytes are the major intravascular storage sites of nitrite in human blood

PubMed Central

Dejam, André; Hunter, Christian J.; Pelletier, Mildred M.; Hsu, Lewis L.; Machado, Roberto F.; Shiva, Sruti; Power, Gordon G.; Kelm, Malte; Gladwin, Mark T.; Schechter, Alan N.

2005-01-01

Plasma levels of nitrite ions have been used as an index of nitric oxide synthase (NOS) activity in vivo. Recent data suggest that nitrite is a potential intravascular repository for nitric oxide (NO), bioactivated by a nitrite reductase activity of deoxyhemoglobin. The precise levels and compartmentalization of nitrite within blood and erythrocytes have not been determined. Nitrite levels in whole blood and erythrocytes were determined using reductive chemiluminescence in conjunction with a ferricyanide-based hemoglobin oxidation assay to prevent nitrite destruction. This method yields sensitive and linear measurements of whole blood nitrite over 24 hours at room temperature. Nitrite levels measured in plasma, erythrocytes, and whole blood from 15 healthy volunteers were 121 plus or minus 9, 288 plus or minus 47, and 176 plus or minus 17 nM, indicating a surprisingly high concentration of nitrite within erythrocytes. The majority of nitrite in erythrocytes is located in the cytosol unbound to proteins. In humans, we found a significant artery-to-vein gradient of nitrite in whole blood and erythrocytes. Shear stress and acetylcholine-mediated stimulation of endothelial NOS significantly increased venous nitrite levels. These studies suggest a dynamic intravascular NO metabolism in which endothelial NOS-derived NO is stabilized as nitrite, transported by erythrocytes, and consumed during arterial-to-venous transit. (Blood. 2005;106:734-739) PMID:15774613

Mapping the hemagglutination domain of rotaviruses.

PubMed Central

Fuentes-Pananá, E M; López, S; Gorziglia, M; Arias, C F

1995-01-01

Most strains of animal rotaviruses are able to agglutinate erythrocytes, and the surface protein VP4 is the virus hemagglutinin. To map the hemagglutination domain on VP4 while preserving the conformation of the protein, we constructed full-length chimeras between the VP4 genes of hemagglutinating (YM) and nonhemagglutinating (KU) rotavirus strains. The parental and chimeric genes were expressed in insect cells, and the recombinant VP4 proteins were evaluated for their capacity to agglutinate human type O erythrocytes. Three chimeric genes, encoding amino acids 1 to 208 (QKU), 93 to 208 (QC), and 93 to 776 (QYM) of the YM VP4 protein in a KU VP4 background, were constructed. YM VP4 and chimeras QKU and QC were shown to specifically hemagglutinate, indicating that the region between amino acids 93 and 208 of YM VP4 is sufficient to determine the hemagglutination activity of the protein. PMID:7884915

Influence of a static magnetic field on the slow freezing of human erythrocytes.

PubMed

Lin, Chun-Yen; Chang, Wei-Jen; Lee, Sheng-Yang; Feng, Sheng-Wei; Lin, Che-Tong; Fan, Kan-Shin; Huang, Haw-Ming

2013-01-01

The aim of this study was to test whether or not a strong static magnetic field (SMF) had a positive effect on the survival rate of frozen erythrocytes. Human erythrocytes were slow freezing at a rate of -1°C/min, to a final temperature of -20°C. During the freezing process, the cells were simultaneously exposed to an SMF with a magnetic induction of 0.2 or 0.4 T. After the cells were thawed, the survival rate, morphology, and function of the thawed erythrocytes were evaluated. Furthermore, tests of membrane fluidity were performed to assess the effect of the SMF on the cell membrane. The slow freezing process coupled with an SMF increased the survival rate of frozen erythrocytes, without any negative effect on the cell morphology or function. The increases in relative survival rates of frozen erythrocytes were 5.7% and 9.1% when the cells were frozen in 0.2 T and 0.4 T groups, respectively. In addition, the 0.4 T group significantly increased the membrane rigidity of the erythrocytes. Slow freezing coupled with a strong SMF produced positive effects on the survival rate of thawed erythrocytes, without changing their normal function.

Assessment of outer hair cell function and blood antioxidant status of rabbits exposed to noise and metal welding fumes.

PubMed

Mirzaee, Ramazan; Allameh, Abdolamir; Mortazavi, Seyed Bagher; Khavanin, Ali; Kazemnejad, Anoshirvan; Akbary, Mehdi

2007-06-01

To investigate the interaction between welding fumes and noise in causation of hearing impairment. Groups of rabbits (n=6) were exposed to noise, welding fumes or combination of both prior to Distortion Product Otoacoustic-Emissions (DPOAEs) analysis. The function of outer hair cells (OHCs) was examined by DPOAE assessment over a broad range of frequencies. Variations in DPOAE amplitude were compared between control (n=6) and exposed (n=18) groups. The DPOAEs levels measured at different frequencies (1379-6299 Hz) were found to decrease significantly (P<0.05) in rabbits exposed to 110 dB sound pressure level (SPL) broadband noise (8h/day, 12 days). In rabbits, exposed to carbon-steel welding fumes alone (157 mg/m(3)), the threshold shift was limited to the high frequencies (2759-6299 Hz), whereas, mixed exposure to noise and fumes resulted in reduction of DPOAEs at all the frequencies. Changes in DPOAEs were associated with increased susceptibility of erythrocytes to oxidation (P<0.05). Exposure to noise or fumes alone or simultaneously, suppressed total antioxidant ability of plasma as measured by ferric reducing ability of plasma (FRAP). Noise alone or in combination with fumes resulted in depletion of blood glutathione (GSH). Despite suppression of FRAP in the exposed groups, GSH was found to remain unchanged due to welding fumes suggesting that antioxidants other than GSH are affected by toxicants present in metal welding fumes. Exposure to very high levels of welding fumes can increase noise-related effects on OHC function by extending hearing threshold shift to wide band frequencies.

The first case of a complete deficiency of diphosphoglycerate mutase in human erythrocytes.

PubMed

Rosa, R; Prehu, M O; Beuzard, Y; Rosa, J

1978-11-01

An inherited and complete deficiency of diphosphoglycerate mutase was discovered in the erythrocytes of a 42-yr-old man of French origin whose blood hemoglobin concentration was 19.0 g/dl. Upon physical examination he was normal with the exception of a ruddy cyanosis. The morphology of his erythrocytes was also normal and there was no evidence of hemolysis. The erythrocyte 2,3-diphosphoglycerate level was below 3% of normal values and, as a consequence, the affinity of the cells for oxygen was increased. Diphosphoglycerate mutase activity was undetectable in erythrocytes as was that of diphosphoglycerate phosphatase. The activities of all the other erythrocyte enzymes that were tested were normal except for nomophosphoglycerate mutase which was diminished to 50% of the normal value. The levels of reduced glutathione, ATP, fructose 1,6-diphosphate, and of triose phosphates were elevated, whereas those of glucose 6-phosphate and fructose 6-phosphate were decreased. This report sheds new light on the role of diphosphoglycerate mutase in the metabolism of erythrocytes.

Clotrimazole enhances lysis of human erythrocytes induced by t-BHP.

PubMed

Lisovskaya, Irene L; Shcherbachenko, Irina M; Volkova, Rimma I; Ataullakhanov, Fazoil I

2009-08-14

Clotrimazole (CLT) is an antifungal and antimalarial agent also effective as a Gardos channel inhibitor. In addition, CLT possesses antitumor properties. Recent data provide evidence that CLT forms a complex with heme (hemin), which produces a more potent lytic effect than heme alone. This study addressed the effect of CLT on the lysis of normal human erythrocytes induced by tert-butyl hydroperoxide (t-BHP). For the first time, it was shown that 10 microM CLT significantly enhanced the lytic effect of t-BHP on erythrocytes in both Ca(2+)-containing and Ca(2+)-free media, suggesting that the effect is not related to Gardos channels. CLT did not affect the rate of free radical generation, the kinetics of GSH degradation, methemoglobin formation and TBARS generation; therefore, we concluded that CLT does not cause additional oxidative damage to erythrocytes treated with t-BHP. It is tempted to speculate that CLT enhances t-BHP-induced changes in erythrocyte volume and lysis largely by forming a complex with hemin released during hemoglobin oxidation in erythrocytes: the CLT-hemin complex destabilizes the cell membrane more potently than hemin alone. If so, the effect of CLT on cell membrane damage during free-radical oxidation may be used to increase the efficacy of antitumor therapy.

Biologically agglutinated eukaryotic microfossil from Cryogenian cap carbonates.

PubMed

Moore, K R; Bosak, T; Macdonald, F A; Lahr, D J G; Newman, S; Settens, C; Pruss, S B

2017-07-01

Cryogenian cap carbonates that overlie Sturtian glacial deposits were formed during a post-glacial transgression. Here, we describe microfossils from the Kakontwe Formation of Zambia and the Taishir Formation of Mongolia-both Cryogenian age, post-Sturtian cap carbonates-and investigate processes involved in their formation and preservation. We compare microfossils from these two localities to an assemblage of well-documented microfossils previously described in the post-Sturtian Rasthof Formation of Namibia. Microfossils from both new localities have 10 ± 1 μm-thick walls composed of carbonaceous matter and aluminosilicate minerals. Those found in the Kakontwe Formation are spherical or ovoid and 90 ± 5 μm to 200 ± 5 μm wide. Structures found in the Taishir Formation are mostly spherical, 50 ± 5 μm to 140 ± 5 μm wide, with distinct features such as blunt or concave edges. Chemical and mineralogical analyses show that the walled structures and the clay fraction extracted from the surrounding sediments are composed of clay minerals, especially muscovite and illite, as well as quartz, iron and titanium oxides, and some dolomite and feldspar. At each locality, the mineralogy of the microfossil walls matched that of the clay fractions of the surrounding sediment. The abundance of these minerals in the walled microfossils relative to the surrounding carbonate matrix and microbial laminae, and the presence of minerals that cannot precipitate from solution (titanium oxide and feldspar), suggests that the composition represents the original mineralogy of the structures. Furthermore, the consistency in mineralogy of both microfossils and sediments across the three basins, and the uniformity of size and shape among mineral grains in the fossil walls indicate that these organisms incorporated these minerals by primary biological agglutination. The discovery of new, mineral-rich microfossil assemblages in microbially laminated and other fine

Sonidegib, a Novel Inhibitor of Suicidal Erythrocyte Death.

PubMed

Al Mamun Bhuyan, Abdulla; Sahu, Itishri; Cao, Hang; Lang, Florian

2018-06-19

The Hedgehog pathway disrupting drug sonidegib is used in the treatment of basal cell carcinoma. Side effects of sonidegib include anemia, which could result either from impaired erythropoiesis or from loss of erythrocytes e.g. due to suicidal erythrocyte death or eryptosis, which is characterized by cell membrane scrambling with phosphatidylserine translocation to the cell surface and by cell shrinkage. Eryptosis is stimulated by cell stress, including energy depletion, hyperosmotic shock, oxidative stress and excessive increase of cytosolic Ca2+ activity ([Ca2+]i). The present study explored, whether sonidegib exerts an effect on eryptosis. Human erythrocytes have been treated with energy depletion (glucose withdrawal for 48 hours), hyperosmotic shock (addition of 550 mM sucrose for 6 hours), oxidative stress (addition of 0.3 mM tert-butylhydroperoxide [tBOOH] for 50 min) or Ca2+ ionophore ionomycin (1 µM for 60 min) in absence and presence of sonidegib (2-6 µg/ ml). After treatment flow cytometry was employed to quantify phosphatidylserine exposure at the cell surface from annexin-V-binding, and cell volume from forward scatter. Hemolysis was estimated from the hemoglobin concentration in the supernatant. In the absence of cell stress exposure to sonidegib did not significantly modify annexin-V-binding or forward scatter, but triggered hemolysis. Energy depletion, hyperosmotic shock, oxidative stress and ionomycin, all markedly and significantly increased the percentage of annexin-V-binding erythrocytes, and decreased the forward scatter. Sonidegib significantly blunted the effect of energy depletion, hyperosmotic shock, and oxidative stress, but not of ionomycin on annexin-V-binding. Sonidegib further significantly blunted the effect of energy depletion, but not of hyperosmotic shock, oxidative stress, and ionomycin on forward scatter. Sonidegib is a novel inhibitor of erythrocyte cell membrane scrambling following energy depletion, hyperosmotic shock and

Use of commercial extenders and alternatives to prevent sperm agglutination for cryopreservation of brown bear semen.

PubMed

Gomes-Alves, S; Alvarez, M; Nicolas, M; Lopez-Urueña, E; Martínez-Rodríguez, C; Borragan, S; de Paz, P; Anel, L

2014-08-01

The objective of this study was to evaluate different bovine and canine commercial semen extenders for cryopreservation of brown bear ejaculates and the effect of semen collection directly into extender on sperm agglutination. Semen samples were obtained by electroejaculation from 13 adult males. In experiment 1, eleven ejaculates from eight bears were used to evaluate Bioxcell and Andromed as extenders, whereas in experiment 2, nine ejaculates from six bears were used to evaluate Triladyl canine, CaniPro, and Extender 2 as extenders. An extender specifically developed for brown bears (Test-Tris-fructose-egg yolk-glycerol, TTF-ULE/bear) served as a control extender in both experiments. After thawing, total and progressive sperm motility and sperm viability were greater (P < 0.05) for TTF-ULE/bear and Andromed extenders than for Bioxcell in experiment 1 and greater (P < 0.05) for TTF-ULE/bear extender than for Triladyl Canine, CaniPro, and Extender 2 in experiment 2. In experiment 3, addition of handling extender (TTF-H) to the semen collection tube for eight ejaculates from seven bears resulted in less (P < 0.05) sperm agglutination in fresh samples (score 0.5 ± 0.2 vs. 1.8 ± 0.4 in diluted and control samples, respectively) with no effect on pre-freeze and post-thawing semen quality. In conclusion, TTF-ULE/bear is the most suitable extender for brown bear semen cryopreservation, but comparable results can be obtained with the commercial extender Andromed. In addition, collection of ejaculates directly in TTF-H extender decreases sperm agglutination in fresh samples. Copyright © 2014 Elsevier Inc. All rights reserved.

Anejaculation following spinal cord injury does not induce sperm-agglutinating antibodies.

PubMed

Dahlberg, A; Hovatta, O

1989-02-01

Antisperm antibodies were tested for by the MAR-test and the tray agglutination test in 16 men with spinal cord injury. None of these men could ejaculate without artificial methods. Seven men ejaculated externally by vibrator stimulation or electroejaculation, while seven exhibited retrograde ejaculation; in two cases no semen was obtained. Sperm density in the external ejaculations was high (average = 405 x 10(6)/ml), with 10-45% motility. None of these 16 men had antisperm antibodies. This result indicates that anejaculation and sperm retention in men with spinal cord injury, even of 30 years duration, does not result in antisperm antibody formation.

The cottontail rabbits of Virginia

USGS Publications Warehouse

Llewellyn, L.M.; Handley, C.O.

1945-01-01

Five races of cottontail rabbits belonging to three species occur in Virginia. One of them, the Mearns cottontail (Sylvilagus floridanus mearnsi), is reported here for the first time. It occurs in six southwestern counties of the state, while the eastern cottontail (S. f. mallurus) occurs in the remainder of the state with the exception of Smith and Fishermans islands off the eastern coast of Cape Charles, where it is replaced by Hitchens cottontail (S. f. hitchensi). The New England cottontail (S. transitionalis) is found on the higher mountain peaks, above 3000 feet, and the swamp rabbit (S. palustris) occurs in the Dismal Swamp region of southeastern Virginia.....The height of the breeding season for the eastern cottontail in Virginia is March and April, but breeding continues through the entire year except in December and January. The average litter size based on embryo counts was 4.7. The sex ratio of 234 specimens from all parts of the state, taken mostly in the December to February period, was 53 males to 47 females. That of a group of 145 rabbits live-trapped at Blacksburg during February and Marchwas 58 males to 42 females. The figures show that males are more active than females during the winter months, and therefore are more easily taken then....In transplanting cottontails from one section of the state to another, it is recommended that only cottontails of the same race as those originally present in the region being restocked be released there....Tularemia is not a common disease among rabbits in Virginia, but the rabbit ticks are often carriers of the disease and may transmit it to rabbits. Rabbit ticks are also found to be carriers of Rocky Mountain fever and American Q. fever. After the ticks drop off the rabbits to hibernate in the ground, which is likely to occur during mid-winter in Virginia, there is relatively little danger of humans contracting tularemia by contact with rabbits. Present laws in Virginia which prohibit rabbit hunting until the

Temperature-dependent changes in erythrocytes' cytosol state during natural and artificial hypobiosis.

PubMed

Repina, S V; Nardid, O A; Marchenko, V S; Shilo, A V

2004-05-01

At present, the question of how the structural state of the erythrocyte cytosol is arranged to maintain essential permeabilities successfully both at normal temperature and during periods with a significant body temperature reduction during hypobiosis remains unanswered. In the present work, we performed comparative investigations of temperature-dependent changes in the cytosol state of erythrocytes from animals subjected to natural (winter hibernating ground squirrels) or artificial hypobiosis. The cytosol state was evaluated by the ESR method of spin probes (TEMPON) within the temperature range of 0-50 degrees C. Erythrocyte resistance to acid hemolysis, which is limited by the permeability of membranes for protons and the state of the anion channel, were determined using the method described by Terskov and Getelson [Biofizika 2 (1957) 259]. A change in cytosol microviscosity of erythrocytes was found as well as a temperature-dependent increase in acid resistance of erythrocytes. Our investigations allow us to conclude that physiological changes occurring in a mammalian organism during natural and artificial hypobiosis are accompanied by structural modifications of the erythrocyte cytosol. The temperature range where these modifications are observed (8, 15, 40 degrees C) suggests that the most probable modifying link is spectrin and/or the sites of its interaction with membrane. The interaction of cytoskeletal components with the cell membrane plays a key role in regulation of membrane permeability, suggesting an important role of this interaction in the adaptive reactions of erythrocytes.

In vitro agglutinin production by earthworm leukocytes.

PubMed

Stein, E A; Cooper, E L

1988-01-01

Leukocytes of the earthworm, Lumbricus terrestris, secrete agglutinins in vitro, as shown by measuring agglutinin titers of the culture medium and by observing secretory rosette formation by leukocytes with erythrocytes. Leukocytes form the highest percentages of secretory rosettes with rabbit erythrocytes (RBC) and with other RBC species in the order: rat, guinea pig, mouse, calf, sheep, horse, goat. Leukocytes displayed allotypic specificity by forming rosettes selectively with erythrocytes from different individual rabbits. Eight sugars inhibited rosette formation, along with the polysaccharide mannan and the glycoproteins thyroglobulin and bovine submaxillary mucin. Cyclohexamide did not affect rosette formation, suggesting that agglutinins may be preformed and stored in leukocytes prior to secretion. Leukocytes also formed E-type rosettes with erythrocytes, but apparently utilized different receptors from those of secretory rosettes since they were not inhibited by the same sugars.

Genotoxic evaluation of pirfenidone using erythrocyte rodent micronucleus assay.

PubMed

Alcántar-Díaz, Blanca E; Gómez-Meda, Belinda C; Zúñiga-González, Guillermo M; Zamora-Perez, Ana L; González-Cuevas, Jaime; Alvarez-Rodríguez, Bertha A; Sánchez-Parada, María Guadalupe; García-Bañuelos, Jesús J; Armendáriz-Borunda, Juan

2012-08-01

Pirfenidone is a non-steroidal antifibrotic compound that has been proposed in clinical protocols and experimental studies as a pharmacological treatment for fibroproliferative diseases. The objective of this study was to determine the genotoxicity or cytotoxicity of three doses of pirfenidone using the micronuclei test in peripheral blood erythrocytes of rodent models. Pirfenidone was administered orally to Balb-C mice for 3 days, and also was administered topically to hairless Sprague Dawley rats during the final stage of gestation. Mice were sampled every 24 h over the course of 6 days; pregnant rats were sampled every 24 h during the last 6 days of gestation, and pups were sampled at birth. Blood smears were analyzed and the frequencies of micronucleated erythrocytes (MNEs), micronucleated polychromatic erythrocytes (MNPCEs), and the proportion of polychromatic erythrocytes (PCEs), were recorded in samples from mice, pregnant rats and rat neonates. Increases in MN frequencies (p<0.03) were noted only in the positive control groups. No genotoxic effects or decreased PCE values were observed neither in newborn rats transplacentally exposed to pirfenidone, or in two adult rodent models when pirfenidone was administered orally or topically. Copyright © 2012 Elsevier Ltd. All rights reserved.

Integrity of erythrocytes of hypercholesterolemic rats during spices treatment.

PubMed

Kempaiah, R K; Srinivasan, K

2002-07-01

In rats rendered hypercholesterolemic by maintaining them on a cholesterol-enriched diet (0.5%) for 8 weeks, inclusion of spice principles--curcumin (0.2%) or capsaicin (0.015%) or the spice--garlic powder (2.0%) in the diet, produced the expected hypolipidemic effect. Plasma cholesterol which was more than 200% that of basal control in hypercholesterolemic rats, was decreased by these dietary spice principles and garlic by 25-39%. Erythrocyte membranes of hypercholesterolemic rats were relatively enriched in cholesterol, which was about 120% of basal control, while membrane phospholipid was unaffected. This resulted in a significant alteration in cholesterol to phospholipid ratio of RBC membranes. Dietary curcumin, capsaicin and garlic were observed to counter this altered lipid profile of erythrocyte membranes in hypercholesterolemic situation by producing a significant 10-14% decrease in membrane cholesterol content. As a result of alteration in membrane structural lipids, the structural integrity of RBCs was also affected. An examination of the osmotic fragility of erythrocytes in various groups, indicated that RBCs of hypercholesterolemic rats were relatively fragile compared to normal controls. Dietary curcumin, capsaicin and garlic appeared to correct this increased fragility of erythrocytes.

Effect of Vibrio parahaemolyticus haemolysin on human erythrocytes.

PubMed

Lang, Philipp A; Kaiser, Stephanie; Myssina, Swetlana; Birka, Christina; Weinstock, Christof; Northoff, Hinnak; Wieder, Thomas; Lang, Florian; Huber, Stephan M

2004-04-01

Haemolysin Kanagawa, a toxin from Vibrio parahaemolyticus, is known to trigger haemolysis. Flux studies indicated that haemolysin forms a cation channel. In the present study, channel properties were elucidated by patch clamp and functional significance of ion fluxes by fluorescence-activated cell sorting (FACS) analysis. Treatment of human erythrocytes with 1 U ml-1 haemolysin within minutes induces a non-selective cation permeability. Moreover, haemolysin activates clotrimazole-sensitive K+ channels, pointing to stimulation of Ca2+-sensitive Gardos channels. Haemolysin (1 U ml-1) leads within 5 min to slight cell shrinkage, which is reversed in Ca2+-free saline. Erythrocytes treated with haemolysin (0.1 U ml-1) do not undergo significant haemolysis within the first 60 min. Replacement of extracellular Na+ with NMDG+ leads to slight cell shrinkage, which is potentiated by 0.1 U ml-1 haemolysin. According to annexin binding, treatment of erythrocytes with 0.1 U ml-1 haemolysin leads within 30 min to breakdown of phosphatidylserine asymmetry of the cell membrane, a typical feature of erythrocyte apoptosis. The annexin binding is significantly blunted at increased extracellular K+ concentrations and by K+ channel blocker clotrimazole. In conclusion, haemolysin Kanagawa induces cation permeability and activates endogenous Gardos K+ channels. Consequences include breakdown of phosphatidylserine asymmetry, which depends at least partially on cellular loss of K+.

Properties of Streptococcus mutans Grown in a Synthetic Medium: Binding of Glucosyltransferase and In Vitro Adherence, and Binding of Dextran/Glucan and Glycoprotein and Agglutination

PubMed Central

Wu-Yuan, Christine D.; Tai, Stella; Slade, Hutton D.

1979-01-01

The influence of culture media on various properties of Streptococcus mutans was investigated. Strains of S. mutans (serotypes c, d, f, and g) were grown in a complex medium (Todd-Hewitt broth [THB]) or a synthetic medium (SYN). The SYN cells, in contrast to THB cells, did not bind extracellular glucosyltransferase and did not produce in vitro adherence. Both types of cells possessed constitutive levels of glucosyltransferase. B13 cells grown in SYN plus invertase-treated glucose possessed the same level of constitutive enzyme as THB cells. In contrast to THB cells, the SYN cells of seven serotype strains did not agglutinate upon the addition of high-molecular-weight dextran/glucan. Significant quantities of lower-molecular-weight (2 × 104 or 7 × 104) dextran and B13 glucan were bound by SYN cells. SYN cells agglutinated weakly in anti-glucan serum (titers, 0 to 16), whereas THB cells possessed titers of 32 to 256. Evidence for the existence of a second binding site in agglutination which does not possess a glucan-like polymer has been obtained. B13 cells grown in invertase-treated THB agglutinated to the same degree as normal THB cells. The nature of this site is unknown. SYN cells possess the type-specific polysaccharide antigen. B13 cells did not bind from THB a glycoprotein which reacts with antisera to the A, B, or T blood group antigens or which allows agglutination upon the addition of dextran. The results demonstrate that S. mutans grown in a chemically defined medium possesse markedly different biochemical and biological activities than cells grown in a complex organic medium. PMID:457252

PMCA activity and membrane tubulin affect deformability of erythrocytes from normal and hypertensive human subjects.

PubMed

Monesterolo, Noelia E; Nigra, Ayelen D; Campetelli, Alexis N; Santander, Verónica S; Rivelli, Juan F; Arce, Carlos A; Casale, Cesar H

2015-11-01

Our previous studies demonstrated formation of a complex between acetylated tubulin and brain plasma membrane Ca(2+)-ATPase (PMCA), and the effect of the lipid environment on structure of this complex and on PMCA activity. Deformability of erythrocytes from hypertensive human subjects was reduced by an increase in membrane tubulin content. In the present study, we examined the regulation of PMCA activity by tubulin in normotensive and hypertensive erythrocytes, and the effect of exogenously added diacylglycerol (DAG) and phosphatidic acid (PA) on erythrocyte deformability. Some of the key findings were that: (i) PMCA was associated with tubulin in normotensive and hypertensive erythrocytes, (ii) PMCA enzyme activity was directly correlated with erythrocyte deformability, and (iii) when tubulin was present in the erythrocyte membrane, treatment with DAG or PA led to increased deformability and associated PMCA activity. Taken together, our findings indicate that PMCA activity is involved in deformability of both normotensive and hypertensive erythrocytes. This rheological property of erythrocytes is affected by acetylated tubulin and its lipid environment because both regulate PMCA activity. Copyright © 2015 Elsevier B.V. All rights reserved.

Rabbit haemorrhagic disease: advantages of cELISA in assessing immunity in wild rabbits (Oryctolagus cuniculus).

PubMed

Zheng, Tao; Parkes, John P

2011-12-15

Rabbit haemorrhagic disease (RHD) is an acute fatal disease of domestic and wild European rabbits (Oryctolagus cuniculus) caused by RHD virus (RHDV). Accurate assessment of immunity is of great importance for the conservation and control of wild rabbits. We evaluated a competitive ELISA (cELISA) against isotype ELISAs for assessing the protective immunity against the disease by challenging 50 wild-caught rabbits with a lethal dose of RHDV. Death or survival to the challenge was used as a criterion to determine the performance characteristics of the assay for the assessment of immunity in rabbits. At 1:10 dilution, a serum exhibiting ≥ 25% inhibition (1:10(25)) was regarded as the presence of RHDV-specific antibodies. Eleven of 16 (68.8%) rabbits with antibodies at 1:10(25) (<1:40) died of RHD. When the cut-off was moved from 25% to 50% inhibition (1:10(50)) at 1:10 serum dilution, the assay sensitivity, specificity and accuracy for the protective immunity were improved from 84%, 54.2% and 69.4% to 84%, 100% and 91.8%, respectively. We also demonstrated at the epitope amino acid sequence level why the presence of the RHDV-cross reactive benign rabbit calicivirus, which interfered with isotype ELISAs, had little impact on the specificity of the cELISA for the diagnosis of RHDV infection. The presence of RHDV-specific antibody at 1:10(50) by the cELISA is a reliable indicator for the protective immunity. In contrast to isotype ELISAs, the cELISA is a valuable specific tool for monitoring the herd immunity to RHD for the conservation and management of wild rabbits in the field. Copyright © 2011 Elsevier B.V. All rights reserved.

Acute dark chocolate ingestion is beneficial for hemodynamics via enhancement of erythrocyte deformability in healthy humans.

PubMed

Radosinska, Jana; Horvathova, Martina; Frimmel, Karel; Muchova, Jana; Vidosovicova, Maria; Vazan, Rastislav; Bernatova, Iveta

2017-03-01

Erythrocyte deformability is an important property of erythrocytes that considerably affects blood flow and hemodynamics. The high content of polyphenols present in dark chocolate has been reported to play a protective role in functionality of erythrocytes. We hypothesized that chocolate might influence erythrocytes not only after repeated chronic intake, but also immediately after its ingestion. Thus, we determined the acute effect of dark chocolate and milk (with lower content of biologically active substances) chocolate intake on erythrocyte deformability. We also focused on selected factors that may affect erythrocyte deformability, specifically nitric oxide production in erythrocytes and total antioxidant capacity of plasma. We determined posttreatment changes in the mentioned parameters 2hours after consumption of chocolate compared with their levels before consumption of chocolate. In contrast to milk chocolate intake, the dark chocolate led to a significantly higher increase in erythrocyte deformability. Nitric oxide production in erythrocytes was not changed after dark chocolate intake, but significantly decreased after milk chocolate. The plasma total antioxidant capacity remained unaffected after ingestion of both chocolates. We conclude that our hypothesis was confirmed. Single ingestion of dark chocolate improved erythrocyte deformability despite unchanged nitric oxide production and antioxidant capacity of plasma. Increased deformability of erythrocytes may considerably improve rheological properties of blood and thus hemodynamics in humans, resulting in better tissue oxygenation. Copyright © 2017 Elsevier Inc. All rights reserved.

Low toxicity method of inhibiting sickling of sickle erythrocytes

DOEpatents

Packer, Lester; Bymun, Edwin N.

1977-01-01

A low toxicity method of inhibiting sickling of sickle erythrocytes which comprises intermixing the erythrocytes with an effective anti-sickling amount of a water-soluble imidoester of the formula RC(=NH)OR' wherein R is an alkyl group of 1 - 8 carbon atoms, particularly 1 - 4 carbon atoms, and R' is an alkyl group of 1 - 4 carbon atoms, specifically methyl or ethyl acetimidate.

QUANTITATIVE ASPECTS OF THE RED BLOOD CELL AGGLUTINATION TEST FOR INFLUENZA VIRUS

PubMed Central

Miller, Gail Lorenz; Stanley, W. M.

1944-01-01

A detailed study has been made of the nature of the variables inherent in the chicken red cell agglutination test for influenza virus in an effort to obtain a method of measurement of biological activity of sufficient accuracy that it might be employed as a reliable index of chemical purity of preparations of the virus. It was found that the temperature at which the test is conducted has a marked effect on the titer, whereas within the range of pH 6–8 the pH has a negligible effect. It was also found that a variation in results may be encountered due to a variation in the specific behavior of red cells from different chickens and to an instability of the red cells themselves. Preparations of purified influenza virus held at 4°C., on the other hand, were found to be stable with respect to chicken red cell agglutinating activity for several months. This fact, together with the fact that in duplicate measurements upon different samples the accuracy was such that the chances were 19 out of 20 that differences of 8.4 per cent in the mean end points were significant, made it possible to establish a reproducible standard of CCA activity based on a unit weight of purified virus material. As a result, it was possible to devise a standardized procedure for carrying out with high accuracy quantitative measurements of influenza virus. PMID:19871362

Thermal dielectroscopy - A new method for studying the membrane skeleton of human erythrocytes

NASA Astrophysics Data System (ADS)

Paarvanova, Boyana; Tacheva, Bilyana; Karabaliev, Miroslav; Ivanov, Ivan T.

2017-11-01

The structure and mechanical properties of erythrocyte plasma membrane are strongly affected by both the dephosphorylation and thermal denaturation (49.5°C) of erythrocyte under-membrane spectrin skeleton. Here, the dielectric loss (DL) of suspensions, containing native erythrocytes or erythrocyte ghost membranes (EGMs), was determined applying a mathematical method to remove the conductive loss from the imaginary capacitance, Cim, of the suspensions. The DL frequency profile of spectrin skeleton was obtained subtracting the DL data collected prior to, and after the denaturation of spectrin at 49.5°C. Spectrin skeleton exhibited narrow bell-shaped DL frequency curve, centered at 1.5 MHz, presumably reflecting the segmental mobility of spectrin. The area of this curve was reduced by 30 % after mild dephosphorylation (starvation of erythrocytes at 37°C for 5 h) and reduced to zero at EGMs resealed with alkaline phosphatase (full dephosphorylation). These results, combined with others, indicate the relevance of dielectric analysis for the study of dynamics and separation of membrane skeleton from the lipid membrane of erythrocytes.

The first case of a complete deficiency of diphosphoglycerate mutase in human erythrocytes.

PubMed Central

Rosa, R; Prehu, M O; Beuzard, Y; Rosa, J

1978-01-01

An inherited and complete deficiency of diphosphoglycerate mutase was discovered in the erythrocytes of a 42-yr-old man of French origin whose blood hemoglobin concentration was 19.0 g/dl. Upon physical examination he was normal with the exception of a ruddy cyanosis. The morphology of his erythrocytes was also normal and there was no evidence of hemolysis. The erythrocyte 2,3-diphosphoglycerate level was below 3% of normal values and, as a consequence, the affinity of the cells for oxygen was increased. Diphosphoglycerate mutase activity was undetectable in erythrocytes as was that of diphosphoglycerate phosphatase. The activities of all the other erythrocyte enzymes that were tested were normal except for nomophosphoglycerate mutase which was diminished to 50% of the normal value. The levels of reduced glutathione, ATP, fructose 1,6-diphosphate, and of triose phosphates were elevated, whereas those of glucose 6-phosphate and fructose 6-phosphate were decreased. This report sheds new light on the role of diphosphoglycerate mutase in the metabolism of erythrocytes. Images PMID:152321

Recombinant Rabbit Leukemia Inhibitory Factor and Rabbit Embryonic Fibroblasts Support the Derivation and Maintenance of Rabbit Embryonic Stem Cells

PubMed Central

Xue, Fei; Ma, Yinghong; Chen, Y. Eugene; Zhang, Jifeng; Lin, Tzu-An; Chen, Chien-Hong; Lin, Wei-Wen; Roach, Marsha; Ju, Jyh-Cherng; Yang, Lan; Du, Fuliang

2012-01-01

Abstract The rabbit is a classical experimental animal species. A major limitation in using rabbits for biomedical research is the lack of germ-line-competent rabbit embryonic stem cells (rbESCs). We hypothesized that the use of homologous feeder cells and recombinant rabbit leukemia inhibitory factor (rbLIF) might improve the chance in deriving germ-line-competent rbES cells. In the present study, we established rabbit embryonic fibroblast (REF) feeder layers and synthesized recombinant rbLIF. We derived a total of seven putative rbESC lines, of which two lines (M5 and M23) were from culture Condition I using mouse embryonic fibroblasts (MEFs) as feeders supplemented with human LIF (hLIF) (MEF+hLIF). Another five lines (R4, R9, R15, R21, and R31) were derived from Condition II using REFs as feeder cells supplemented with rbLIF (REF+rbLIF). Similar derivation efficiency was observed between these two conditions (8.7% vs. 10.2%). In a separate experiment with 2×3 factorial design, we examined the effects of feeder cells (MEF vs. REF) and LIFs (mLIF, hLIF vs. rbLIF) on rbESC culture. Both Conditions I and II supported satisfactory rbESC culture, with similar or better population doubling time and colony-forming efficiency than other combinations of feeder cells with LIFs. Rabbit ESCs derived and maintained on both conditions displayed typical ESC characteristics, including ESC pluripotency marker expression (AP, Oct4, Sox2, Nanog, and SSEA4) and gene expression (Oct4, Sox2, Nanog, c-Myc, Klf4, and Dppa5), and the capacity to differentiate into three primary germ layers in vitro. The present work is the first attempt to establish rbESC lines using homologous feeder cells and recombinant rbLIF, by which the rbESCs were derived and maintained normally. These cell lines are unique resources and may facilitate the derivation of germ-line-competent rbESCs. PMID:22775411

Recombinant rabbit leukemia inhibitory factor and rabbit embryonic fibroblasts support the derivation and maintenance of rabbit embryonic stem cells.

PubMed

Xue, Fei; Ma, Yinghong; Chen, Y Eugene; Zhang, Jifeng; Lin, Tzu-An; Chen, Chien-Hong; Lin, Wei-Wen; Roach, Marsha; Ju, Jyh-Cherng; Yang, Lan; Du, Fuliang; Xu, Jie

2012-08-01

The rabbit is a classical experimental animal species. A major limitation in using rabbits for biomedical research is the lack of germ-line-competent rabbit embryonic stem cells (rbESCs). We hypothesized that the use of homologous feeder cells and recombinant rabbit leukemia inhibitory factor (rbLIF) might improve the chance in deriving germ-line-competent rbES cells. In the present study, we established rabbit embryonic fibroblast (REF) feeder layers and synthesized recombinant rbLIF. We derived a total of seven putative rbESC lines, of which two lines (M5 and M23) were from culture Condition I using mouse embryonic fibroblasts (MEFs) as feeders supplemented with human LIF (hLIF) (MEF+hLIF). Another five lines (R4, R9, R15, R21, and R31) were derived from Condition II using REFs as feeder cells supplemented with rbLIF (REF+rbLIF). Similar derivation efficiency was observed between these two conditions (8.7% vs. 10.2%). In a separate experiment with 2×3 factorial design, we examined the effects of feeder cells (MEF vs. REF) and LIFs (mLIF, hLIF vs. rbLIF) on rbESC culture. Both Conditions I and II supported satisfactory rbESC culture, with similar or better population doubling time and colony-forming efficiency than other combinations of feeder cells with LIFs. Rabbit ESCs derived and maintained on both conditions displayed typical ESC characteristics, including ESC pluripotency marker expression (AP, Oct4, Sox2, Nanog, and SSEA4) and gene expression (Oct4, Sox2, Nanog, c-Myc, Klf4, and Dppa5), and the capacity to differentiate into three primary germ layers in vitro. The present work is the first attempt to establish rbESC lines using homologous feeder cells and recombinant rbLIF, by which the rbESCs were derived and maintained normally. These cell lines are unique resources and may facilitate the derivation of germ-line-competent rbESCs.

An individual-based model of rabbit viral haemorrhagic disease on European wild rabbits (Oryctolagus cuniculus)

USGS Publications Warehouse

Fa, John E.; Sharples, Colin M.; Bell, Diana J.; DeAngelis, Donald L.

2001-01-01

We developed an individual-based model of Rabbit Viral Hemorrhagic Disease (RVHD) for European wild rabbits (Oryctolagus cuniculus L.), representing up to 1000 rabbits in four hectares. Model output for productivity and recruitment matched published values. The disease was density-dependent and virulence affected outcome. Strains that caused death after several days produced greater overall mortality than strains in which rabbits either died or recovered very quickly. Disease effect also depended on time of year. We also elaborated a larger scale model representing 25 km2 and 100,000+ rabbits, split into a number of grid-squares. This was a more traditional model that did not represent individual rabbits, but employed a system of dynamic equations for each grid-square. Disease spread depended on probability of transmission between neighboring grid-squares. Potential recovery from a major population crash caused by the disease relied on disease virulence and frequency of recurrence. The model's dependence on probability of disease transmission between grid-squares suggests the way that the model represents the spatial distribution of the population affects simulation. Although data on RVHD in Europe are lacking, our models provide a basis for describing the disease in realistic detail and for assessing influence of various social and spatial factors on spread.

Immunogold-agglutination assay for direct detection of HPV-16 E6 and L1 proteins from clinical specimens.

PubMed

Bhattarakosol, Parvapan; Plaignam, Kamolwan; Sereemaspun, Amornpun

2018-05-01

HPV-16 infection is the most common cause of cervical cancer. As HPV-16 transforms the cell, E6 oncoprotein is over-expressed. Therefore, molecular detection of HPV-16 E6 mRNA is now being used for diagnosis and prediction of cancer development. Besides detecting E6 mRNA, a rapid lateral flow detecting the E6 protein using enzyme immunoassay is also now on market with a sensitivity of 53.5% for cervical intraepithelial neoplasia (CIN)-3 or more severe (CIN-3+). Here, an immunogold-agglutination assay was developed to detect not only HPV-16 E6 protein but also L1, a major capsid protein found in the productive stage of the virus. Evaluation of this test using HPV-16 DNA positive cervical samples showed that the HPV-16 E6 immunogold-agglutination assay results correlated well with the progression of the cervical lesions, i.e., 10.34% of CIN-1, 68.75% of CIN-3 and 80% of cancer (CaCx) and none for healthy normal samples. Interestingly, the HPV-16 L1 protein was found in most of the cases with cancer indicating the possibility of virion production. Immunogold-agglutination assay for E6 protein is simpler, easier to be performed with a sensitivity of 73.1% for CIN-3+ suggesting a good method for laboratory diagnostic use. Copyright © 2018 Elsevier B.V. All rights reserved.

Erythrocytic Adenosine Monophosphate as an Alternative Purine Source in Plasmodium falciparum*

PubMed Central

Cassera, María B.; Hazleton, Keith Z.; Riegelhaupt, Paul M.; Merino, Emilio F.; Luo, Minkui; Akabas, Myles H.; Schramm, Vern L.

2008-01-01

Plasmodium falciparum is a purine auxotroph, salvaging purines from erythrocytes for synthesis of RNA and DNA. Hypoxanthine is the key precursor for purine metabolism in Plasmodium. Inhibition of hypoxanthine-forming reactions in both erythrocytes and parasites is lethal to cultured P. falciparum. We observed that high concentrations of adenosine can rescue cultured parasites from purine nucleoside phosphorylase and adenosine deaminase blockade but not when erythrocyte adenosine kinase is also inhibited. P. falciparum lacks adenosine kinase but can salvage AMP synthesized in the erythrocyte cytoplasm to provide purines when both human and Plasmodium purine nucleoside phosphorylases and adenosine deaminases are inhibited. Transport studies in Xenopus laevis oocytes expressing the P. falciparum nucleoside transporter PfNT1 established that this transporter does not transport AMP. These metabolic patterns establish the existence of a novel nucleoside monophosphate transport pathway in P. falciparum. PMID:18799466

Erythrocytic adenosine monophosphate as an alternative purine source in Plasmodium falciparum.

PubMed

Cassera, María B; Hazleton, Keith Z; Riegelhaupt, Paul M; Merino, Emilio F; Luo, Minkui; Akabas, Myles H; Schramm, Vern L

2008-11-21

Plasmodium falciparum is a purine auxotroph, salvaging purines from erythrocytes for synthesis of RNA and DNA. Hypoxanthine is the key precursor for purine metabolism in Plasmodium. Inhibition of hypoxanthine-forming reactions in both erythrocytes and parasites is lethal to cultured P. falciparum. We observed that high concentrations of adenosine can rescue cultured parasites from purine nucleoside phosphorylase and adenosine deaminase blockade but not when erythrocyte adenosine kinase is also inhibited. P. falciparum lacks adenosine kinase but can salvage AMP synthesized in the erythrocyte cytoplasm to provide purines when both human and Plasmodium purine nucleoside phosphorylases and adenosine deaminases are inhibited. Transport studies in Xenopus laevis oocytes expressing the P. falciparum nucleoside transporter PfNT1 established that this transporter does not transport AMP. These metabolic patterns establish the existence of a novel nucleoside monophosphate transport pathway in P. falciparum.

In Vitro Induction of Erythrocyte Phosphatidylserine Translocation by the Natural Naphthoquinone Shikonin

PubMed Central

Lupescu, Adrian; Bissinger, Rosi; Jilani, Kashif; Lang, Florian

2014-01-01

Shikonin, the most important component of Lithospermum erythrorhizon, has previously been shown to exert antioxidant, anti-inflammatory, antithrombotic, antiviral, antimicrobial and anticancer effects. The anticancer effect has been attributed to the stimulation of suicidal cell death or apoptosis. Similar to the apoptosis of nucleated cells, erythrocytes may experience eryptosis, the suicidal erythrocyte death characterized by cell shrinkage and by phosphatidylserine translocation to the erythrocyte surface. Triggers of eryptosis include the increase of cytosolic Ca2+-activity ([Ca2+]i) and ceramide formation. The present study explored whether Shikonin stimulates eryptosis. To this end, Fluo 3 fluorescence was measured to quantify [Ca2+]i, forward scatter to estimate cell volume, annexin V binding to identify phosphatidylserine-exposing erythrocytes, hemoglobin release to determine hemolysis and antibodies to quantify ceramide abundance. As a result, a 48 h exposure of human erythrocytes to Shikonin (1 µM) significantly increased [Ca2+]i, increased ceramide abundance, decreased forward scatter and increased annexin V binding. The effect of Shikonin (1 µM) on annexin V binding was significantly blunted, but not abolished by the removal of extracellular Ca2+. In conclusion, Shikonin stimulates suicidal erythrocyte death or eryptosis, an effect at least partially due to the stimulation of Ca2+ entry and ceramide formation. PMID:24828755

Reduction of hydrogen peroxide-induced erythrocyte damage by Carica papaya leaf extract.

PubMed

Okoko, Tebekeme; Ere, Diepreye

2012-06-01

To investigate the in vitro antioxidant potential of Carica papaya (C. papaya) leaf extract and its effect on hydrogen peroxide-induced erythrocyte damage assessed by haemolysis and lipid peroxidation. Hydroxyl radical scavenging activities, hydrogen ion scavenging activity, metal chelating activity, and the ferrous ion reducing ability were assessed as antioxidant indices. In the other experiment, human erythrocytes were treated with hydrogen peroxide to induce erythrocyte damage. The extract (at various concentrations) was subsequently incubated with the erythrocytes and later analysed for haemolysis and lipid peroxidation as indices for erythrocyte damage. Preliminary investigation of the extract showed that the leaf possessed significant antioxidant and free radical scavenging abilities using in vitro models in a concentration dependent manner (P<0.05). The extract also reduced hydrogen peroxide induced erythrocyte haemolysis and lipid peroxidation significantly when compared with ascorbic acid (P<0.05). The IC50 values were 7.33 mg/mL and 1.58 mg/mL for inhibition of haemolysis and lipid peroxidation, respectively. In all cases, ascorbic acid (the reference antioxidant) possessed higher activity than the extract. The findings show that C. papaya leaves possess significant bioactive potential which is attributed to the phytochemicals which act in synergy. Thus, the leaves can be exploited for pharmaceutical and nutritional purposes.

Receptor-like glycocompounds in human milk that inhibit classical and El Tor Vibrio cholerae cell adherence (hemagglutination).

PubMed Central

Holmgren, J; Svennerholm, A M; Lindblad, M

1983-01-01

The two biotypes of Vibrio cholerae were found to have cell-associated hemagglutinins which differ with regard to binding to different species of erythrocytes and inhibition by monosaccharides. A total of 12 classical V. cholerae strains (Inaba or Ogawa) strongly agglutinated human erythrocytes in a reaction specifically inhibited by L-fucose, whereas 12 El Tor strains preferably agglutinated chicken erythrocytes, a reaction reversed by D-mannose or by higher concentrations of D-fructose, D-glucose, alpha-methyl-D-mannoside, or sucrose. Milk from Swedish women inhibited both of these adherence reactions, and the predominating inhibitory activity for each reaction resisted boiling, was destroyed by periodate treatment, and bound a concanavalin A-Sepharose column, suggesting a carbohydrate structure. Further characterization indicated that the inhibitory activity for classical V. cholerae hemagglutination was distributed about equally on glycoprotein and free oligosaccharide, but was not present on glycolipid. The El Tor inhibiting activity, on the other hand, was almost exclusively of a high-molecular-weight glycoprotein nature. These results support our previous suggestion (Holmgren et al., Infect. Immun. 33:136-141, 1981) that human milk may contain receptor-like glycocompounds which can prevent bacterial adherence by competition with receptors on target cells. PMID:6295953

Biophysical Properties of Plasmodium falciparum-Infected Erythrocytes from Novel Analysis of the Flicker Phenomena

NASA Astrophysics Data System (ADS)

Arie, Takayuki; Jin, Albert; Dvorak, James

2002-03-01

Infectious processes often modulate the intrinsic properties of vertebrate cells. We studied the modulation of human erythrocyte flicker during the intra-erythrocytic cycle of Plasmodium falciparum malaria using video microscopy imaging and a data analysis system of our design to extract flicker spectra and lateral cell edge undulations of individual erythrocytes at various stages of infection. The total flicker power, the power weighted mean flicker frequency, the mode amplitudes of lateral undulations, and the time correlation of translation mode was quantified by infectious stage and modeled theoretically. Our results suggest that malaria-infected erythrocytes become increasingly more rigid following infection and provide an insight into the modulation of erythrocyte cytoplasmic viscosity by the parasites. These studies of malaria-infected erythrocytes elucidate the kinetics of both membrane and cellular changes that are relevant to blood microcirculation and improve our understanding of the malaria disease process.

Plasmodium falciparum FIKK Kinase Members Target Distinct Components of the Erythrocyte Membrane

PubMed Central

Scheidig-Benatar, Christine; Cooke, Brian M.; Scherf, Artur

2010-01-01

Background Modulation of infected host cells by intracellular pathogens is a prerequisite for successful establishment of infection. In the human malaria parasite Plasmodium falciparum, potential candidates for erythrocyte remodelling include the apicomplexan-specific FIKK kinase family (20 members), several of which have been demonstrated to be transported into the erythrocyte cytoplasm via Maurer's clefts. Methodology In the current work, we have knocked out two members of this gene family (Pf fikk7.1 and Pf fikk12), whose products are localized at the inner face of the erythrocyte membrane. Both mutant parasite lines were viable and erythrocytes infected with these parasites showed no detectable alteration in their ability to adhere in vitro to endothelial receptors such as chondroitin sulfate A and CD36. However, we observed sizeable decreases in the rigidity of infected erythrocytes in both knockout lines. Mutant parasites were further analyzed using a phospho-proteomic approach, which revealed distinct phosphorylation profiles in ghost preparations of infected erythrocytes. Knockout parasites showed a significant reduction in the level of phosphorylation of a protein of approximately 80 kDa for FIKK12-KO in trophozoite stage and a large protein of about 300 kDa for FIKK7.1-KO in schizont stage. Conclusions Our results suggest that FIKK members phosphorylate different membrane skeleton proteins of the infected erythrocyte in a stage-specific manner, inducing alterations in the mechanical properties of the parasite-infected red blood cell. This suggests that these host cell modifications may contribute to the parasites' survival in the circulation of the human host. PMID:20668526

Plasmodium falciparum FIKK kinase members target distinct components of the erythrocyte membrane.

PubMed

Nunes, Marta C; Okada, Mami; Scheidig-Benatar, Christine; Cooke, Brian M; Scherf, Artur

2010-07-23

Modulation of infected host cells by intracellular pathogens is a prerequisite for successful establishment of infection. In the human malaria parasite Plasmodium falciparum, potential candidates for erythrocyte remodelling include the apicomplexan-specific FIKK kinase family (20 members), several of which have been demonstrated to be transported into the erythrocyte cytoplasm via Maurer's clefts. In the current work, we have knocked out two members of this gene family (Pf fikk7.1 and Pf fikk12), whose products are localized at the inner face of the erythrocyte membrane. Both mutant parasite lines were viable and erythrocytes infected with these parasites showed no detectable alteration in their ability to adhere in vitro to endothelial receptors such as chondroitin sulfate A and CD36. However, we observed sizeable decreases in the rigidity of infected erythrocytes in both knockout lines. Mutant parasites were further analyzed using a phospho-proteomic approach, which revealed distinct phosphorylation profiles in ghost preparations of infected erythrocytes. Knockout parasites showed a significant reduction in the level of phosphorylation of a protein of approximately 80 kDa for FIKK12-KO in trophozoite stage and a large protein of about 300 kDa for FIKK7.1-KO in schizont stage. Our results suggest that FIKK members phosphorylate different membrane skeleton proteins of the infected erythrocyte in a stage-specific manner, inducing alterations in the mechanical properties of the parasite-infected red blood cell. This suggests that these host cell modifications may contribute to the parasites' survival in the circulation of the human host.

A Lectin-Like Receptor is Involved in Invasion of Erythrocytes by Plasmodium falciparum

NASA Astrophysics Data System (ADS)

Jungery, M.; Pasvol, G.; Newbold, C. I.; Weatherall, D. J.

1983-02-01

Glycophorin both in solution and inserted into liposomes blocks invasion of erythrocytes by the malaria parasite Plasmodium falciparum. Furthermore, one sugar, N-acetyl-D-glucosamine (GlcNAc), completely blocks invasion of the erythrocyte by this parasite. GlcNAc coupled to bovine serum albumin to prevent the sugar entering infected erythrocytes was at least 100,000 times more effective than GlcNAc alone. Bovine serum albumin coupled to lactose or bovine serum albumin alone had no effect on invasion. These results suggest that the binding of P. falciparum to erythrocytes is lectin-like and is determined by carbohydrates on glycophorin.

Infrared spectroscopic investigation of erythrocyte membrane-smoke interactions due to chronic cigarette smoking.

PubMed

Sherif, Mahmoud S; Mervat, Ali A; Eman, Aly M

2017-07-01

Cigarette smoking is a serious health problem throughout the world, with a complicated and not totally clear bio-effect. In this study, erythrocytes were obtained from healthy male volunteers aged 22 ± 2 years and, the possible effects of three cigarette smoking rates namely 10, 15 and 20 cigarette/day on erythrocytes membrane characteristics were examined by Fourier transform infrared spectroscopy (FTIR). The results of this study indicate many smoking-dependent variations on erythrocytes membrane without an obvious dose-response relationship. There was disruption in the acyl chain packing; changes in membrane order and phases as well as membrane proteins becoming more folded. These physico-chemical changes should have an impact on the function of erythrocytes and may explain the complex interaction of cigarette smoke mainstream with erythrocyte membrane and to some extent clarify the pathological processes associated with cigarette smoking.

Photodynamic effects on human and chicken erythrocytes

NASA Astrophysics Data System (ADS)

Kimel, Sol; Koenig, Karsten; Berns, Michael W.

1995-02-01

The intracellular accumulation of a variety of photosensitizers in human (non-nucleated) and chicken (nucleated) erythrocytes, as well as the photodynamically induced hemolysis were studied using 488 nm laser microirradiation (15 (mu) W, 100X) and confocal laser scanning fluorescence microscopy. Cells incubated with the negatively charged hydrophilic compounds TPPS4 and Pd-TPPS4 exhibited no significant fluorescence before irradiation, but developed strong fluorescence in the cellular and nuclear membranes following photoinduced membrane damage. In contrast, microirradiation of Photofrin-incubated erythrocytes showed instantaneous fluorescence which decreased due to photodegradation. For the cationic, hydrophilic dye Methylene Blue, significant fluorescence was detected in the nucleus only. Following ALA incubation, large intercellular differences were observed in fluorescence in the red spectral region. These differences are probably due to the differential ability of individual erythrocytes to biosynthesize protoporphyrin IX. Photofrin was the most efficient photosensitizer to induce hemolysis. Higher radiant exposures were required for lysis of nucleated than of human red blood cells, except in the case of Methylene Blue. Irradiation was more efficient for unwashed cell suspensions than for washed suspensions, indicating the non-negligible role of extracellular photosensitizing molecules.

[The 2,3-diphosphoglycerate shunt and stabilization of the ATP level in mammalian erythrocytes].

PubMed

Ataullakhanov, A I; Ataullakhanov, F I; Vitvitskiĭ, V M; Zhabotinskiĭ, A M; Pichugin, A V

1985-06-01

The mechanisms of regulation of energy metabolism in erythrocytes of various mammalian species were investigated. In native erythrocytes of man, sheep, cow, dog and mouse the dependencies of the rates of glucose uptake on ATP concentration (i.e., regulatory parameters of glycolysis) were measured. These parameters plotted in normalized coordinates are not species-specific (invariant). The dependence of the rate of ATP-consuming processes on ATP concentration has been studied for the first time in intact mammalian erythrocytes. This dependence was found to be linear only in the species, in whose erythrocytes the activity of 2,3-diphosphoglycerate shunt is practically zero. In all species under study, the stabilization of ATP level is provided for mainly by the hexokinase-phosphofructokinase system. A comparison of regulatory mechanisms of energy metabolism in mammalian (sheep, cow) erythrocytes, in which the 2,3-diphosphoglycerate shunt is absent, with human and animal erythrocytes, in which this pathway is active, points to the important role of the 2,3-diphosphoglycerate shunt in regulation of energy conversion in erythrocytes. This shunt operates as an additional stabilizer protecting the cell from extremal influences.

Micro-Raman spectroscopy study of the effect of Mid-Ultraviolet radiation on erythrocyte membrane.

PubMed

Li, N; Li, S X; Guo, Z Y; Zhuang, Z F; Li, R; Xiong, K; Chen, S J; Liu, S H

2012-07-02

Mid-Ultraviolet (UVB) has a significant influence on human health. In this study, human erythrocytes were exposed to UVB to investigate the effects of UVB radiation on erythrocytes membrane. And Micro-Raman spectroscopy was employed to detect the damage. Principal component analysis (PCA) was used to classify the control erythrocytes and the irradiated erythrocytes. Results showed that the erythrocytes membrane was damaged by Mid-Ultraviolet (UVB) radiation. The intensity of the Raman peaks at 1126 cm(-1) and 1082 cm(-1) were used to calculate the Longitudinal Order-Parameters in Chains (S(trans)) which can present the liquidity and ionic permeability of erythrocyte membrane. After UVB radiation for 30 min, both the liquidity and ionic permeability decreased. At the same time, the intensity of the peaks at 1302 cm(-1) (α-helix), 1254 cm(-1) (random coil), 1452 cm(-1) and 1430 cm(-1) (CH(2)/CH(3) stretch) have also changed which indicated the membrane protein also been damaged by UVB. In the whole process of radiation, the more UVB radiation dose the more damage on the erythrocyte membrane. Copyright © 2012 Elsevier B.V. All rights reserved.

[Physical essence of erythrocytic sedimentation rate in the gravitation field of the earth].

PubMed

Cherniĭ, A N

2009-01-01

The erythrocytic sedimentation rate method has been long known in medicine and extensively used in laboratory practice in tuberculosis facilities. However, many authors note that the erythrocytic sedimentation rate phenomenon has not clearly understood. By applying the total theory of relativity and quantum mechanics, the author discloses the physical essence of erythrocytic sedimentation in the gravitation field of the Earth.

siRNA delivery targeting to the lung via agglutination-induced accumulation and clearance of cationic tetraamino fullerene.

PubMed

Minami, Kosuke; Okamoto, Koji; Doi, Kent; Harano, Koji; Noiri, Eisei; Nakamura, Eiichi

2014-05-12

The efficient treatment of lung diseases requires lung-selective delivery of agents to the lung. However, lung-selective delivery is difficult because the accumulation of micrometer-sized carriers in the lung often induces inflammation and embolization-related toxicity. Here we demonstrate a lung-selective delivery system of small interfering RNA (siRNA) by controlling the size of carrier vehicle in blood vessels. The carrier is made of tetra(piperazino)fullerene epoxide (TPFE), a water-soluble cationic tetraamino fullerene. TPFE and siRNA form sub-micrometer-sized complexes in buffered solution and these complexes agglutinate further with plasma proteins in the bloodstream to form micrometer-sized particles. The agglutinate rapidly clogs the lung capillaries, releases the siRNA into lung cells to silence expression of target genes, and is then cleared rapidly from the lung after siRNA delivery. We applied our delivery system to an animal model of sepsis, indicating the potential of TPFE-based siRNA delivery for clinical applications.

siRNA delivery targeting to the lung via agglutination-induced accumulation and clearance of cationic tetraamino fullerene

NASA Astrophysics Data System (ADS)

Minami, Kosuke; Okamoto, Koji; Doi, Kent; Harano, Koji; Noiri, Eisei; Nakamura, Eiichi

2014-05-01

The efficient treatment of lung diseases requires lung-selective delivery of agents to the lung. However, lung-selective delivery is difficult because the accumulation of micrometer-sized carriers in the lung often induces inflammation and embolization-related toxicity. Here we demonstrate a lung-selective delivery system of small interfering RNA (siRNA) by controlling the size of carrier vehicle in blood vessels. The carrier is made of tetra(piperazino)fullerene epoxide (TPFE), a water-soluble cationic tetraamino fullerene. TPFE and siRNA form sub-micrometer-sized complexes in buffered solution and these complexes agglutinate further with plasma proteins in the bloodstream to form micrometer-sized particles. The agglutinate rapidly clogs the lung capillaries, releases the siRNA into lung cells to silence expression of target genes, and is then cleared rapidly from the lung after siRNA delivery. We applied our delivery system to an animal model of sepsis, indicating the potential of TPFE-based siRNA delivery for clinical applications.

Minimization of bacterial size allows for complement evasion and is overcome by the agglutinating effect of antibody

PubMed Central

Dalia, Ankur B.; Weiser, Jeffrey N.

2011-01-01

SUMMARY The complement system, which functions by lysing pathogens directly or by promoting their uptake by phagocytes, is critical for controlling many microbial infections. Here we show that in Streptococcus pneumoniae, increasing bacterial chain length sensitizes this pathogen to complement deposition and subsequent uptake by human neutrophils. Consistent with this, we show that minimizing chain length provides wild-type bacteria with a competitive advantage in vivo in a model of systemic infection. Investigating how the host overcomes this virulence strategy, we find that antibody promotes complement-dependent opsonophagocytic killing of Streptococcus pneumoniae and lysis of Haemophilus influenzae independent of Fc-mediated effector functions. Consistent with the agglutinating effect of antibody, F(ab′)2 but not Fab could promote this effect. Therefore, increasing pathogen size, whether by natural changes in cellular morphology or via antibody-mediated agglutination, promotes complement-dependent killing. These observations have broad implications for how cell size and morphology can affect virulence among pathogenic microbes. PMID:22100164

siRNA delivery targeting to the lung via agglutination-induced accumulation and clearance of cationic tetraamino fullerene

PubMed Central

MINAMI, Kosuke; OKAMOTO, Koji; DOI, Kent; HARANO, Koji; NOIRI, Eisei; NAKAMURA, Eiichi

2014-01-01

The efficient treatment of lung diseases requires lung-selective delivery of agents to the lung. However, lung-selective delivery is difficult because the accumulation of micrometer-sized carriers in the lung often induces inflammation and embolization-related toxicity. Here we demonstrate a lung-selective delivery system of small interfering RNA (siRNA) by controlling the size of carrier vehicle in blood vessels. The carrier is made of tetra(piperazino)fullerene epoxide (TPFE), a water-soluble cationic tetraamino fullerene. TPFE and siRNA form sub-micrometer-sized complexes in buffered solution and these complexes agglutinate further with plasma proteins in the bloodstream to form micrometer-sized particles. The agglutinate rapidly clogs the lung capillaries, releases the siRNA into lung cells to silence expression of target genes, and is then cleared rapidly from the lung after siRNA delivery. We applied our delivery system to an animal model of sepsis, indicating the potential of TPFE-based siRNA delivery for clinical applications. PMID:24814863

[Changes of protein tyrosine phosphorylation in erythrocyte band 3 glucose-6-phosphate dehydrogenase deficiency].

PubMed

Yu, Guoyu; Li, Jialin; Tian, Xingya; Lin, Hong; Wang, Xiaoying

2002-11-01

To explore the hemolytic mechanism of glucose-6-phosphate dehydrogenase (G6PD) deficient erythrocytes in the view of phosphorylation of membrane protein. The alternation of membrane protein phosphorylation and the effect of dithiothreitol (DTT) on protein phosphorylation were analysed by Western blot technique. The activity of phosphotyrosine phosphatase (PTPs) was determined by using p-nitrophenyl phosphate as substrate. Tyrosine phosphorylation of band 3 protein was obviously enhanced in G6PD-deficient erythrocytes. The activity of PTPs was low compared to the normal erythrocytes. The level of phosphotyrosine in G6PD-deficient erythrocytes incubated with DTT was almost the same as in those without DTT. The results were consistent with the activity of PTPs. PTPs activity reduction and tyrosine phosphorylation enhancement induced by oxidation in G6PD deficiency play an important role in erythrocytes hemolysis. However, the alternation of thiol group is not the only factor affecting the activity of PTPs in G6PD-deficient erythrocytes.

Augmented water binding and low cellular water content in erythrocytes of camel and camelids.

PubMed

Bogner, P; Csutora, P; Cameron, I L; Wheatley, D N; Miseta, A

1998-12-01

We investigated a link between hemoglobin primary structure, hemoglobin hydrophobicity-hydrophilicity, and erythrocyte water content in various mammalian species. Some hemoglobin molecules, particularly those of the camel and camelids, contain more charged amino acid residues and are more hydrophilic than the hemoglobins of human and a number of other mammalian species. To test the in vivo significance of these alterations of hemoglobin primary structure, we determined the osmotically unresponsive erythrocyte water fractions in mannit solutions of various osmolarities at 4 degreesC. Among the species investigated, the size of the osmotically unresponsive erythrocyte water fraction relates in a positive linear way to hemoglobin hydrophilicity. The extreme low total erythrocyte water content of camel erythrocytes (1.1-1.3 g water/g dry mass) may be explained by a comparatively high osmotically unresponsive erythrocyte water fraction. It is proposed that alterations of hemoglobin sequences of camel and camelids may be the part of a natural selection process aimed at protecting these animals against osmotic dehydration in arid environments.

[Diagnosis of human brucellosis. Role of pH in the seroagglutination test and influence of pH on the agglutinating activity of IgM, IgG and IgA antibodies].

PubMed

Rubio Vallejo, Manuel; del Pozo, José L; Del Pozo León, José Luis; Hernández-Molina, Juan Manuel; Dorronsoro Ibero, Inés; Marrodán Ciordia, Teresa; Díaz García, Ramón

2002-04-01

To evaluate the role of pH in the seroagglutination test (SAT)and Rose Bengal (RB) test, and to determine the influence of pH on the agglutinating activity of IgM, IgG and IgA antibodies. The SAT was performed at pH 7.2 or pH 5.0 in standard microtiter-type polystyrene plates using Ring Test antigen or the Brucella suspension (BRUCAPT) provided in the Brucellacapt kits. Specific antibodies against native hapten were determined by radial immunodiffusion. Additionally, IgG, IgA and IgM fractions were separated from 8 sera by absorption chromatography and their agglutinating capacity was studied at pH 7.2 and 5.0. We studied 72 sera from patients with clinical brucellosis taken at the time of hospitalization, 16 from persons in contact with infected animals, and 16 from healthy donors. SAT results at pH 5.0 correlated with those obtained with the Rose Bengal test. Four Rose Bengal-positive sera were found to be SAT-negative at pH 7.2 and SAT-positive at pH 5.0. SAT performed at pH 5.0 with BRUCAPT antigen yielded higher titers than tests performed at pH 7.2 or 5.0 with Ring Test antigen (p < 0.001), with highest titers in IDR-positive sera. Among the 8 IgG fractions, all but one agglutinated at pH 7.2, and in 4, IgG titers showed significant increases at pH 5.0. Three IgA fractions were SAT-negative at pH 7.2 and SAT-positive at pH 5.0; the other 5 agglutinated at both pH conditions and were DTT-sensitive. All IgA fractions but one were positive by Rose Bengal. Agglutinating activity of the IgM fraction was not affected by pH. The SAT performed with the buffer and antigen suspension included in the Brucellacapt kit (pH 5.0) is highly useful for detecting agglutinating and non-agglutinating antibodies at pH 7.2.

Spray drying for preservation of erythrocytes: effect of atomization on hemolysis.

PubMed

McLean, Mary; Han, Xiao-Yue; Higgins, Adam Z

2013-04-01

Spray drying has the potential to enable storage of erythrocytes at room temperature in the dry state. The spray drying process involves atomization of a liquid into small droplets and drying of the droplets in a gas stream. In this short report, we focus on the atomization process. To decouple atomization from drying, erythrocyte suspensions were sprayed with a two-fluid atomizer nozzle using humid nitrogen as the atomizing gas. The median droplet size was less than 100 μm for all of the spray conditions investigated, indicating that the suspensions were successfully atomized. Hemolysis was significantly affected by the hematocrit of the erythrocyte suspension, the suspension flow rate, and the atomizing gas flow rate (p<0.01 in all cases). Under appropriate conditions, it was possible to achieve less than 2% hemolysis, suggesting that spray drying may be a feasible option for erythrocyte biopreservation.

Strain-specific variations in cation content and transport in mouse erythrocytes

PubMed Central

Rivera, Alicia; Zee, Robert Y. L.; Alper, Seth L.; Peters, Luanne L.

2013-01-01

Studies of ion transport pathophysiology in hematological disorders and tests of possible new therapeutic agents for these disorders have been carried out in various mouse models because of close functional similarities between mouse and human red cells. We have explored strain-specific differences in erythrocyte membrane physiology in 10 inbred mouse strains by determining erythrocyte contents of Na+, K+, and Mg2+, and erythrocyte transport of ions via the ouabain-sensitive Na-K pump, the amiloride-sensitive Na-H exchanger (NHE1), the volume and chloride-dependent K-Cl cotransporter (KCC), and the charybdotoxin-sensitive Gardos channel (KCNN4). Our data reveal substantial strain-specific and sex-specific differences in both ion content and trans-membrane ion transport in mouse erythrocytes. These differences demonstrate the feasibility of identifying specific quantitative trait loci for erythroid ion transport and content in genetically standardized inbred mouse strains. PMID:23482811

Strain-specific variations in cation content and transport in mouse erythrocytes.

PubMed

Rivera, Alicia; Zee, Robert Y L; Alper, Seth L; Peters, Luanne L; Brugnara, Carlo

2013-05-01

Studies of ion transport pathophysiology in hematological disorders and tests of possible new therapeutic agents for these disorders have been carried out in various mouse models because of close functional similarities between mouse and human red cells. We have explored strain-specific differences in erythrocyte membrane physiology in 10 inbred mouse strains by determining erythrocyte contents of Na(+), K(+), and Mg(2+), and erythrocyte transport of ions via the ouabain-sensitive Na-K pump, the amiloride-sensitive Na-H exchanger (NHE1), the volume and chloride-dependent K-Cl cotransporter (KCC), and the charybdotoxin-sensitive Gardos channel (KCNN4). Our data reveal substantial strain-specific and sex-specific differences in both ion content and trans-membrane ion transport in mouse erythrocytes. These differences demonstrate the feasibility of identifying specific quantitative trait loci for erythroid ion transport and content in genetically standardized inbred mouse strains.

Hemin-induced suicidal erythrocyte death.

PubMed

Gatidis, Sergios; Föller, Michael; Lang, Florian

2009-08-01

Several diseases, such as malaria, sickle cell disease, and ischemia/reperfusion may cause excessive formation of hemin, which may in turn trigger hemolysis. A variety of drugs and diseases leading to hemolysis triggers suicidal erythrocyte death or eryptosis, i.e., cell membrane scrambling and cell shrinkage. Eryptosis is elicited by increased cytosolic Ca(2+) activity and by ceramide. The present study explored whether hemin stimulates eryptosis. Cell membrane scrambling was estimated from annexin V-binding to phosphatidylserine exposed at the cell surface, cell shrinkage from forward scatter in fluorescence-activated cell sorter analysis, cytosolic Ca(2+) activity from Fluo3 fluorescence and ceramide formation from fluorescence-labeled antibody binding. Exposure to hemin (1-10 microM) within 48 h significantly increased annexin V-binding, decreased forward scatter, increased cytosolic Ca(2+) activity, and stimulated ceramide formation. In conclusion, hemin stimulates suicidal cell death, which may in turn contribute to the clearance of circulating erythrocytes and thus to anemia.

Detection of acute childhood meningitis by PCR, culture and agglutination tests in Tabriz, Iran.

PubMed

Ghotaslou, Reza; Farajnia, Safar; Yeganeh, Fatemeh; Abdoli-Oskouei, Shahram; Ahangarzadeh Rezaee, Mohammad; Barzegar, Mohammad

2012-01-01

Meningitis is one of the hazardous and life threatening infections and is associated with mortality and morbidity. The aim of this study was to determine etiological agents of childhood bacterial meningitis. The culture, Gram staining, agglutination and PCR assays were used to examine CSF specimens from 277 patients with presumed bacterial meningitis for the occurrence of 4 most common infectious agents consist of N. meningitis, H. influnsae, S. pneumoniae and S. agalactiae between 2008 and 2009 at different wards of the Children Hospital of Tabriz. The mean age of patients was 35 ± 2 (Mean ± SEM) month, (minimum 11 days maximum 14 years), of all cases 59.6% male and 40.4% female. Overall the diagnosis was confirmed with a CSF culture in 11/277 (3.97%), by agglutination test in 14/277 (5.05%). The isolated bacteria included S. pneumoniae 5 cases, H. influnsae 2 cases, N. meningitis 3 cases and P. aeroginusae 1 case. A positive PCR assay allowed us to diagnose bacterial meningitis in 19 patients (6.8%). In the present study, we found PCR to be a useful and sensitive method for the detection of bacterial DNA in the CSF samples from suspected meningitis patients. Furthermore, to maximize management of meningitis cases, a combination of culture and PCR is necessary.

Exo-erythrocytic development of avian malaria and related haemosporidian parasites.

PubMed

Valkiūnas, Gediminas; Iezhova, Tatjana A

2017-03-03

Avian malaria parasites (Plasmodium spp.) and related haemosporidians (Haemosporida) are responsible for diseases which can be severe and even lethal in avian hosts. These parasites cause not only blood pathology, but also damage various organs due to extensive exo-erythrocytic development all over the body, which is not the case during Plasmodium infections in mammals. However, exo-erythrocytic development (tissue merogony or schizogony) remains the most poorly investigated part of life cycle in all groups of wildlife haemosporidian parasites. In spite of remarkable progress in studies of genetic diversity, ecology and evolutionary biology of avian haemosporidians during the past 20 years, there is not much progress in understanding patterns of exo-erythrocytic development in these parasites. The purpose of this review is to overview the main information on exo-erythrocytic development of avian Plasmodium species and related haemosporidian parasites as a baseline for assisting academic and veterinary medicine researchers in morphological identification of these parasites using tissue stages, and to define future research priorities in this field of avian malariology. The data were considered from peer-reviewed articles and histological material that was accessed in zoological collections in museums of Australia, Europe and the USA. Articles describing tissue stages of avian haemosporidians were included from 1908 to the present. Histological preparations of various organs infected with the exo-erythrocytic stages of different haemosporidian parasites were examined. In all, 229 published articles were included in this review. Exo-erythrocytic stages of avian Plasmodium, Fallisia, Haemoproteus, Leucocytozoon, and Akiba species were analysed, compared and illustrated. Morphological characters of tissue stages that can be used for diagnostic purposes were specified. Recent molecular studies combined with histological research show that avian haemosporidians are more

Erythrocyte acetylcholinesterase as biomarker of pesticide exposure: new and forgotten insights.

PubMed

Assis, Caio R D; Linhares, Amanda G; Cabrera, Mariana P; Oliveira, Vagne M; Silva, Kaline C C; Marcuschi, Marina; Maciel Carvalho, Elba V M; Bezerra, Ranilson S; Carvalho, Luiz B

2018-05-24

Acetylcholinesterase (AChE) acts on the hydrolysis of acetylcholine, rapidly removing this neurotransmitter at cholinergic synapses and neuromuscular junctions as well as in neuronal growth and differentiation, modulation of cell adhesion ("electrotactins") and aryl-acylamidase activity (AAA). This enzyme is also found in erythrocyte, as 160 kDa dimer that anchors to the plasma membrane via glycophosphatidylinositol. The function of this enzyme in erythrocytes has not yet been elucidated; however, it is suspected to participate in cell-to-cell interactions. Here, a review on erythrocyte AChE characteristics and use as biomarker for organophosphorus and carbamate insecticides is presented since it is the first specific target/barrier of the action of these pesticides, besides plasma butyrylcholinesterase (BChE). However, some past and current methods have disadvantages: (a) not discriminating the activities of AChE and BChE; (b) low accuracy due to interference of hemoglobin in whole blood samples. On the other hand, extraction methods of hemoglobin-free erythrocyte AChE allows: (a) the freezing and transporting of samples; (b) samples free of colorimetric interference; (c) data from only erythrocyte AChE activity; (d) erythrocyte AChE specific activity presents higher correlation with the central nervous system AChE than other peripheral ChEs; (e) slow spontaneous regeneration against anti-ChEs agents of AChE in comparison to BChE, thus increasing the chances of detecting such compounds following longer interval after exposure. As monitoring perspectives, hemoglobin-free methodologies may be promising alternatives to assess the degree of exposure since they are not influenced by this interfering agent.

Modification of Erythrocyte Membrane Fatty Acid Contents After Kidney Transplantation: A Prospective Study.

PubMed

Son, Y K; Kwon, H; Lee, H W; Jeong, E G; Lee, S M; Kim, S E; Park, Y; An, W S

2018-06-01

Modifications of erythrocyte membrane fatty acid (FA) contents may affect cellular function or transmembrane receptors. One cross-sectional study has shown that kidney transplant (KTP) recipients have lower erythrocyte membrane oleic acid content than dialysis patients do. Therefore, we prospectively tested whether erythrocyte membrane contents of FA including oleic acid change after KTP. We recruited 23 KTP recipients (September 2011 through May 2014). Blood samples were obtained immediately before KTP and 6 months after. Erythrocyte membrane FA contents were measured by gas chromatography. Mean age of the enrolled KTP recipients was 45.3 ± 10.9 years, and men represented 66.7% of the cases. ABO-incompatible KTPs constituted 14.3% and cadaver donors 42.9% of the cases. Steroids, mycophenolate mofetil, and tacrolimus were used as immunosuppressive treatment. There was no significant difference in dietary consumption between time points before and 6 months after KTP. Total cholesterol and low-density lipoprotein cholesterol levels were significantly higher at 6 months after KTP as compared with baseline. Erythrocyte membrane contents of polyunsaturated FA, ω-3 FA, ω-6 FA, and the ω-3 index were significantly higher, but erythrocyte membrane contents of total saturated FAs, total monounsaturated FAs, including oleic acid, total trans-FA, palmitoleic acid, and the ω-6-to-ω-3 ratio were significantly lower at 6 months after KTP. Erythrocyte membrane FA contents significantly changed toward a more favorable cardiovascular profile after KTP. These changes in erythrocyte membrane FA contents may be related to improved renal function because of the absence of significant dietary changes. Copyright © 2018 Elsevier Inc. All rights reserved.

N-ethylmaleimide activates a Cl−-independent component of K+ flux in mouse erythrocytes

PubMed Central

Shmukler, Boris E.; Hsu, Ann; Alves, Jessica; Trudel, Marie; Rust, Marco B.; Hubner, Christian A.; Rivera, Alicia; Alper, Seth L.

2013-01-01

The K-Cl cotransporters (KCCs) of mouse erythrocytes exhibit higher basal activity than those of human erythrocytes, but are similarly activated by cell swelling, by hypertonic urea, and by staurosporine. However, the dramatic stimulation of human erythroid KCCs by N-ethylmaleimide (NEM) is obscured in mouse erythrocytes by a prominent NEM-stimulated K+ efflux that lacks Cl−-dependence. The NEM-sensitivity of Cl−-independent K+ efflux of mouse erythrocytes is lower than that of KCC. The genetically engineered absence of the K-Cl cotransporters KCC3 and KCC1 from mouse erythrocytes does not modify Cl−-independent K+ efflux. Mouse erythrocytes genetically devoid of the Gardos channel KCNN4 show increased NEM-sensitivity of both Cl−-independent K+ efflux and K-Cl cotransport. The increased NEM-sensitivity and stimulation magnitude of Cl−-independent K+ efflux in mouse erythrocytes expressing transgenic hypersickling human hemoglobin SAD (HbSAD) is independent of the presence of KCC3 and KCC1, but absence of KCNN4 reduces the stimulatory effect of HbSAD. NEM-stimulated Cl−-independent K+ efflux of mouse red cells is insensitive to ouabain and bumetanide, but partially inhibited by chloroquine, barium, and amiloride. The NEM-stimulated activity is modestly reduced at pH 6.0, but not significantly altered at pH 8.0, and abolished at 0°C. Although the molecular identity of this little-studied K+ efflux pathway of mouse erythrocytes remains unknown, it’s potential role in the pathophysiology of sickle red cell dehydration will be important for extrapolation of studies in mouse models of sickle cell disease to our understanding of humans with sickle cell anemia. PMID:23481459

Descriptive parameters of the erythrocyte aggregation phenomenon using a laser transmission optical chip

NASA Astrophysics Data System (ADS)

Toderi, Martín A.; Castellini, Horacio V.; Riquelme, Bibiana D.

2017-01-01

The study of red blood cell (RBC) aggregation is of great interest because of its implications for human health. Altered RBC aggregation can lead to microcirculatory problems as in vascular pathologies, such as hypertension and diabetes, due to a decrease in the erythrocyte surface electric charge and an increase in the ligands present in plasma. The process of erythrocyte aggregation was studied in stasis situation (free shear stresses), using an optical chip based on the laser transmission technique. Kinetic curves of erythrocyte aggregation under different conditions were obtained, allowing evaluation and characterization of this process. Two main characteristics of blood that influence erythrocyte aggregation were analyzed: the erythrocyte surface anionic charge (EAC) after digestion with the enzyme trypsin and plasmatic protein concentration in suspension medium using plasma dissolutions in physiological saline with human albumin. A theoretical approach was evaluated to obtain aggregation and disaggregation ratios by syllectograms data fitting. Sensible parameters (Amp100, t) regarding a reduced erythrocyte EAC were determined, and other parameters (AI, M-Index) resulted that are representative of a variation in the plasmatic protein content of the suspension medium. These results are very useful for further applications in biomedicine.

Blood Group Antigens on HeLa Cells shown by Mixed Agglutination

PubMed Central

Kelus, A.; Gurner, B. W.; Coombs, R. R. A.

1959-01-01

The mixed agglutination reaction has been used for investigating the presence of blood group antigens on the surface of human cervical carcinoma cells (HeLa) cultured for eight years in vitro. The H antigen was demonstrated in the absence of A and B. The MN-type antigen has been found as well as Tja. Treatment of HeLa cells with ficin greatly enhanced the reaction of anti-H and anti-Tja with the corresponding antigens on HeLa cells. The authors failed to show the following antigens: Rh(D) and Rh(c), S, P, Lea, Leb, Lua and Lub. ImagesFIG. 1FIG. 2 PMID:14405338

STUDIES OF ANTIGENIC DIFFERENCES AMONG STRAINS OF INFLUENZA A BY MEANS OF RED CELL AGGLUTINATION

PubMed Central

Hirst, George K.

1943-01-01

A study of cross inhibition tests among strains of influenza A virus and their antisera showed that the results obtained were subject to a certain amount of variation due to the red cells, the virus suspensions, and the ferret antisera employed. Methods have been demonstrated for handling the data obtained from such tests, so that these variables were corrected or avoided, making it possible to use the agglutination technique for antigenic comparisons. The antigenic pattern of eighteen strains of influenza A virus, obtained from the 1940–41 epidemic in the United States, has been compared by means of agglutination inhibition tests with ferret antisera. No significant antigenic differences were found among sixteen of these strains (all isolated from throat washings by the inoculation of chick embryos) although they were obtained from individuals in widely separated regions of the country. Two strains, from cases occurring early in the epidemic and isolated from throat washings by ferret and mouse passage, showed a slight but significant strain difference from the other strains and from each other. One of the 1940–41 strains on cross test resembled the PR8 strain more closely than any other stock strain tested. PMID:19871338

Reduction of hydrogen peroxide-induced erythrocyte damage by Carica papaya leaf extract

PubMed Central

Okoko, Tebekeme; Ere, Diepreye

2012-01-01

Objective To investigate the in vitro antioxidant potential of Carica papaya (C. papaya) leaf extract and its effect on hydrogen peroxide-induced erythrocyte damage assessed by haemolysis and lipid peroxidation. Methods Hydroxyl radical scavenging activities, hydrogen ion scavenging activity, metal chelating activity, and the ferrous ion reducing ability were assessed as antioxidant indices. In the other experiment, human erythrocytes were treated with hydrogen peroxide to induce erythrocyte damage. The extract (at various concentrations) was subsequently incubated with the erythrocytes and later analysed for haemolysis and lipid peroxidation as indices for erythrocyte damage. Results Preliminary investigation of the extract showed that the leaf possessed significant antioxidant and free radical scavenging abilities using in vitro models in a concentration dependent manner (P<0.05). The extract also reduced hydrogen peroxide induced erythrocyte haemolysis and lipid peroxidation significantly when compared with ascorbic acid (P<0.05). The IC50 values were 7.33 mg/mL and 1.58 mg/mL for inhibition of haemolysis and lipid peroxidation, respectively. In all cases, ascorbic acid (the reference antioxidant) possessed higher activity than the extract. Conclusions The findings show that C. papaya leaves possess significant bioactive potential which is attributed to the phytochemicals which act in synergy. Thus, the leaves can be exploited for pharmaceutical and nutritional purposes. PMID:23569948

Surface properties of Entamoeba: increased rates of human erythrocyte phagocytosis in pathogenic strains

PubMed Central

1978-01-01

The assertion that ingestion of human erythrocytes is restricted to invasive strains of Entamoeba histolytica has not been evaluated previously by comparative studies. In this report we describe the in vitro ingestion of human erythrocytes by pathogenic and nonpathogenic Entamoeba. Microscopic evaluation of erythrophagocytosis by eight different Entamoeba grown in culture revealed that strains of E. histolytica isolated from cases of human dysentery show a much higher rate of erythrocyte ingestion than nonpathogenic strains. However, all strains are able to phagocytize erythrocytes. The extremely high rate of phagocytic activity shown by pathogenic E. histolytica could be one of the properties related to the pathogenicity of this parasitic protozoan. PMID:722237

Very Deep Convolutional Neural Networks for Morphologic Classification of Erythrocytes.

PubMed

Durant, Thomas J S; Olson, Eben M; Schulz, Wade L; Torres, Richard

2017-12-01

Morphologic profiling of the erythrocyte population is a widely used and clinically valuable diagnostic modality, but one that relies on a slow manual process associated with significant labor cost and limited reproducibility. Automated profiling of erythrocytes from digital images by capable machine learning approaches would augment the throughput and value of morphologic analysis. To this end, we sought to evaluate the performance of leading implementation strategies for convolutional neural networks (CNNs) when applied to classification of erythrocytes based on morphology. Erythrocytes were manually classified into 1 of 10 classes using a custom-developed Web application. Using recent literature to guide architectural considerations for neural network design, we implemented a "very deep" CNN, consisting of >150 layers, with dense shortcut connections. The final database comprised 3737 labeled cells. Ensemble model predictions on unseen data demonstrated a harmonic mean of recall and precision metrics of 92.70% and 89.39%, respectively. Of the 748 cells in the test set, 23 misclassification errors were made, with a correct classification frequency of 90.60%, represented as a harmonic mean across the 10 morphologic classes. These findings indicate that erythrocyte morphology profiles could be measured with a high degree of accuracy with "very deep" CNNs. Further, these data support future efforts to expand classes and optimize practical performance in a clinical environment as a prelude to full implementation as a clinical tool. © 2017 American Association for Clinical Chemistry.

Parathyroid hormone ablation alters erythrocyte parameters that are rescued by calcium-sensing receptor gene deletion

PubMed Central

Romero, Jose R.; Youte, Rodeler; Brown, Edward M.; Pollak, Martin R.; Goltzman, David; Karaplis, Andrew; Pong, Lie-Chin; Chien, Lawrence; Chattopadhyay, Naibedya; Rivera, Alicia

2013-01-01

The mechanisms by which parathyroid hormone (PTH) produces anemia, are unclear. Parathyroid hormone secretion is regulated by the extracellular Ca2+-sensing receptor. We investigated the effects of ablating PTH on hematological indices and erythrocytes volume regulation in wild-type, PTH-null and Ca2+-sensing receptor-null/PTH-null mice. The erythrocyte parameters were measured in whole mouse blood and volume regulatory systems were determined by plasma membrane K+ fluxes and osmotic fragility was measured by hemoglobin determination at varying osmolarities. We observed that the absence of PTH significantly increases mean erythrocyte volume and reticulocyte counts, while decreasing erythrocyte counts, hemoglobin, hematocrit, and mean corpuscular hemoglobin concentration. These changes were accompanied by increases in erythrocyte cation content, a denser cell population and increased K+ permeability, which were in part mediated by activation of the K+/Cl− cotransporter and Gardos channel. In addition we observed that erythrocyte osmotic fragility in PTH-null compared with wild-type mice was enhanced. When Ca2+-sensing receptor gene was deleted on the background of PTH-null mice, we observed that several of the alterations in erythrocyte parameters of PTH-null mice were largely rescued, particularly those related to erythrocyte volume, K+ fluxes and osmotic fragility, and became similar to those observed in wild-type mice. Our results demonstrate that Ca2+-sensing receptor and parathyroid hormone are functionally coupled to maintain erythrocyte homeostasis. PMID:23528155

Parathyroid hormone ablation alters erythrocyte parameters that are rescued by calcium-sensing receptor gene deletion.

PubMed

Romero, Jose R; Youte, Rodeler; Brown, Edward M; Pollak, Martin R; Goltzman, David; Karaplis, Andrew; Pong, Lie-Chin; Chien, Lawrence; Chattopadhyay, Naibedya; Rivera, Alicia

2013-07-01

The mechanisms by which parathyroid hormone (PTH) produces anemia are unclear. Parathyroid hormone secretion is regulated by the extracellular Ca2+ -sensing receptor. We investigated the effects of ablating PTH on hematological indices and erythrocytes volume regulation in wild-type, PTH-null, and Ca2+ -sensing receptor-null/PTH-null mice. The erythrocyte parameters were measured in whole mouse blood, and volume regulatory systems were determined by plasma membrane K+ fluxes, and osmotic fragility was measured by hemoglobin determination at varying osmolarities. We observed that the absence of PTH significantly increases mean erythrocyte volume and reticulocyte counts, while decreasing erythrocyte counts, hemoglobin, hematocrit, and mean corpuscular hemoglobin concentration. These changes were accompanied by increases in erythrocyte cation content, a denser cell population, and increased K+ permeability, which were in part mediated by activation of the K+ /Cl- cotransporter and Gardos channel. In addition we observed that erythrocyte osmotic fragility in PTH-null compared with wild-type mice was enhanced. When Ca2+ -sensing receptor gene was deleted on the background of PTH-null mice, we observed that several of the alterations in erythrocyte parameters of PTH-null mice were largely rescued, particularly those related to erythrocyte volume, K+ fluxes and osmotic fragility, and became similar to those observed in wild-type mice. Our results demonstrate that Ca2+ -sensing receptor and parathyroid hormone are functionally coupled to maintain erythrocyte homeostasis. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

[Age-related change in the alpha-tocopherolquinone/alpha-tocopherol ratio in the rat erythrocyte membrane].

PubMed

Yanagawa, K; Takeda, H; Matsumiya, T; Takasaki, M

1999-05-01

alpha-Tocopherol (alpha-Toc), a lipophilic phenolic antioxidant that is localized mainly in the biomembrane, protects cells against oxidation-associated cytotoxicity by prevention of membrane lipid peroxidation, maintenance of the redox balance intracellular thiols and stabilization of the membrane structure. We investigated the age-related changes in redox dynamics of alpha-Toc in plasma and erythrocyte membrane of an elderly (66 weeks old) and young group (10 weeks old). Total, alpha-, beta + gamma-, delta-Toc and alpha-tocopherolquinone (alpha-TocQ) in plasma and erythrocyte membrane were determined by high-performance liquid chromatography (HPLC) with a series of multiple coulometric working electrodes (CWE). Rat venous blood sample was divided into plasma and erythrocyte layers by centrifugation, and then erythrocyte membrane sample was prepared according to the method of Dodge et al. under a stream of nitrogen. In plasma, total and alpha-Toc concentrations were increased, and beta + gamma-, delta-Toc and alpha-TocQ concentrations were decreased age-dependently. In the erythrocyte membrane, total, alpha-TocQ concentrations and three fractions of tocopherols decreased age-dependently. Also, a decrease in the alpha-TocQ/alpha-Toc ratio in erythrocyte membrane was observed in the elderly group. These findings suggest that the alpha-Toc uptake in erythrocyte membrane and utilization rate of alpha-Toc in erythrocyte membrane decline age-dependently. This decline may promote membrane lipid peroxidation. alpha-Toc redox dynamics in erythrocyte membrane were useful to investigate the pathophysiology of aging mechanisms related to oxidative stress.

Slow Freezing Coupled Static Magnetic Field Exposure Enhances Cryopreservative Efficiency—A Study on Human Erythrocytes

PubMed Central

Lin, Chun-Yen; Wei, Po-Li; Chang, Wei-Jen; Huang, Yung-Kai; Feng, Sheng-Wei; Lin, Che-Tong; Lee, Sheng-Yang; Huang, Haw-Ming

2013-01-01

The aim of this study was to assess the cryoprotective effect of static magnetic fields (SMFs) on human erythrocytes during the slow cooling procedure. Human erythrocytes suspended in 20% glycerol were slowly frozen with a 0.4-T or 0.8-T SMF and then moved to a −80°C freezer for 24 hr. The changes in survival rate, morphology, and metabolites of the thawed erythrocytes were examined. To understand possible cryoprotective mechanisms of SMF, membrane fluidity and dehydration stability of SMF-exposed erythrocytes were tested. For each test, sham-exposed erythrocytes were used as controls. Our results showed that freezing coupled with 0.4-T or 0.8-T SMFs significantly increased the relative survival ratios of the frozen-thawed erythrocytes by 10% and 20% (p<0.001), respectively. The SMFs had no effect on erythrocyte morphology and metabolite levels. However, membrane fluidity of the samples exposed to 0.8-T SMF decreased significantly (p<0.05) in the hydrophobic regions. For the dehydration stability experiments, the samples exposed to 0.8-T SMF exhibited significantly lower (p<0.05) hemolysis. These results demonstrate that a 0.8-T SMF decreases membrane fluidity and enhances erythrocyte membrane stability to resist dehydration damage caused by slow cooling procedures. PMID:23520546

Sphingosine-1-phosphate promotes erythrocyte glycolysis and oxygen release for adaptation to high-altitude hypoxia

PubMed Central

Sun, Kaiqi; Zhang, Yujin; D'Alessandro, Angelo; Nemkov, Travis; Song, Anren; Wu, Hongyu; Liu, Hong; Adebiyi, Morayo; Huang, Aji; Wen, Yuan E.; Bogdanov, Mikhail V.; Vila, Alejandro; O'Brien, John; Kellems, Rodney E.; Dowhan, William; Subudhi, Andrew W.; Jameson-Van Houten, Sonja; Julian, Colleen G.; Lovering, Andrew T.; Safo, Martin; Hansen, Kirk C.; Roach, Robert C.; Xia, Yang

2016-01-01

Sphingosine-1-phosphate (S1P) is a bioactive signalling lipid highly enriched in mature erythrocytes, with unknown functions pertaining to erythrocyte physiology. Here by employing nonbiased high-throughput metabolomic profiling, we show that erythrocyte S1P levels rapidly increase in 21 healthy lowland volunteers at 5,260 m altitude on day 1 and continue increasing to 16 days with concurrently elevated erythrocyte sphingonisne kinase 1 (Sphk1) activity and haemoglobin (Hb) oxygen (O2) release capacity. Mouse genetic studies show that elevated erythrocyte Sphk1-induced S1P protects against tissue hypoxia by inducing O2 release. Mechanistically, we show that intracellular S1P promotes deoxygenated Hb anchoring to the membrane, enhances the release of membrane-bound glycolytic enzymes to the cytosol, induces glycolysis and thus the production of 2,3-bisphosphoglycerate (2,3-BPG), an erythrocyte-specific glycolytic intermediate, which facilitates O2 release. Altogether, we reveal S1P as an intracellular hypoxia-responsive biolipid promoting erythrocyte glycolysis, O2 delivery and thus new therapeutic opportunities to counteract tissue hypoxia. PMID:27417539

Assessment of red blood cell parameters and peripheral smear at different temperatures in case of cold agglutination disease.

PubMed

Gupta, V

2014-03-01

Cold agglutination disease (CAD) is characterized by an auto-antibody which is able to agglutinate red blood cells (RBCs) at temperatures lower than that of the body, and subsequently to activate the complement system responsible for lysis of RBCs. Patients show hemolytic anemia of varying degrees of severity, which arise or worsen upon exposure to low temperatures. We describe a case who presented with fever and symptoms of asthenia. His investigations yielded bizarre RBC parameters which led to suspicion of a rare CAD, which was confirmed on reviewing RBC parameters, peripheral smear and direct Coomb's test at different temperatures. Hence, we suggest assessment of bizarre RBC parameters and peripheral smear can help in laboratory testing and diagnosis of CAD. It should also not pose embarrassment in laboratory testing to the pathologist for making an early and accurate diagnosis, thus emphasizing the need for an early treatment of CAD.

Detailed methodology for high resolution scanning electron microscopy (SEM) of murine malaria parasitized-erythrocytes.

PubMed

Hayakawa, Eri H; Matsuoka, Hiroyuki

2016-10-01

Scanning electron microscopy (SEM) is a powerful tool used to investigate object surfaces and has been widely applied in both material science and biology. With respect to the study of malaria, SEM revealed that erythrocytes infected with Plasmodium falciparum, a human parasite, display 'knob-like' structures on their surface comprising parasitized proteins. However, detailed methodology for SEM studies of malaria parasites is lacking in the literature making such studies challenging. Here, we provide a step-by-step guide to preparing Plasmodium-infected erythrocytes from two mouse strains for SEM analysis with minimal structural deterioration. We tested three species of murine malaria parasites, P. berghei, P. yoelii, and P. chabaudi, as well as non-parasitized human erythrocytes and P. falciparum-infected erythrocytes for comparisons. Our data demonstrated that the surface structures of parasitized erythrocytes between the three species of murine parasites in the two different strains of mice were indistinguishable and no surface alterations were observed in P. falciparum-erythrocytes. Our SEM observations contribute towards an understanding of the molecular mechanisms of parasite maturation in the erythrocyte cytoplasm and, along with future studies using our detailed methodology, may help to gain insight into the clinical phenomena of human malaria. Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Magnetic measurements on human erythrocytes: Normal, beta thalassemia major, and sickle

NASA Astrophysics Data System (ADS)

Sakhnini, Lama

2003-05-01

In this article magnetic measurements were made on human erythrocytes at different hemoglobin states (normal and reduced hemoglobin). Different blood samples: normal, beta thalassemia major, and sickle were studied. Beta thalassemia major and sickle samples were taken from patients receiving lifelong blood transfusion treatment. All samples examined exhibited diamagnetic behavior. Beta thalassemia major and sickle samples showed higher diamagnetic susceptibilities than that for the normal, which was attributed to the increase of membrane to hemoglobin volume ratio of the abnormal cells. Magnetic measurements showed that the erythrocytes in the reduced state showed less diamagnetic response in comparison with erythrocytes in the normal state. Analysis of the paramagnetic component of magnetization curves gave an effective magnetic moment of μeff=7.6 μB per reduced hemoglobin molecule. The same procedure was applied to sickle and beta thalassemia major samples and values for μeff were found to be comparable to that of the normal erythrocytes.

N-ethylmaleimide activates a Cl(-)-independent component of K(+) flux in mouse erythrocytes.

PubMed

Shmukler, Boris E; Hsu, Ann; Alves, Jessica; Trudel, Marie; Rust, Marco B; Hubner, Christian A; Rivera, Alicia; Alper, Seth L

2013-06-01

The K-Cl cotransporters (KCCs) of mouse erythrocytes exhibit higher basal activity than those of human erythrocytes, but are similarly activated by cell swelling, by hypertonic urea, and by staurosporine. However, the dramatic stimulation of human erythroid KCCs by N-ethylmaleimide (NEM) is obscured in mouse erythrocytes by a prominent NEM-stimulated K(+) efflux that lacks Cl(-)-dependence. The NEM-sensitivity of Cl(-)-independent K(+) efflux of mouse erythrocytes is lower than that of KCC. The genetically engineered absence of the K-Cl cotransporters KCC3 and KCC1 from mouse erythrocytes does not modify Cl(-)-independent K(+) efflux. Mouse erythrocytes genetically devoid of the Gardos channel KCNN4 show increased NEM-sensitivity of both Cl(-)-independent K(+) efflux and K-Cl cotransport. The increased NEM-sensitivity and stimulation magnitude of Cl(-)-independent K(+) efflux in mouse erythrocytes expressing transgenic hypersickling human hemoglobin SAD (HbSAD) are independent of the presence of KCC3 and KCC1, but absence of KCNN4 reduces the stimulatory effect of HbSAD. NEM-stimulated Cl(-)-independent K(+) efflux of mouse red cells is insensitive to ouabain and bumetanide, but partially inhibited by chloroquine, barium, and amiloride. The NEM-stimulated activity is modestly reduced at pH6.0 but not significantly altered at pH8.0, and is abolished at 0°C. Although the molecular identity of this little-studied K(+) efflux pathway of mouse erythrocytes remains unknown, its potential role in the pathophysiology of sickle red cell dehydration will be important for the extrapolation of studies in mouse models of sickle cell disease to our understanding of humans with sickle cell anemia. Copyright © 2013 Elsevier Inc. All rights reserved.

The Trw Type IV Secretion System of Bartonella Mediates Host-Specific Adhesion to Erythrocytes

PubMed Central

Vayssier-Taussat, Muriel; Le Rhun, Danielle; Deng, Hong Kuan; Biville, Francis; Cescau, Sandra; Danchin, Antoine; Marignac, Geneviève; Lenaour, Evelyne; Boulouis, Henri Jean; Mavris, Maria; Arnaud, Lionel; Yang, Huanming; Wang, Jing; Quebatte, Maxime; Engel, Philipp; Saenz, Henri; Dehio, Christoph

2010-01-01

Bacterial pathogens typically infect only a limited range of hosts; however, the genetic mechanisms governing host-specificity are poorly understood. The α-proteobacterial genus Bartonella comprises 21 species that cause host-specific intraerythrocytic bacteremia as hallmark of infection in their respective mammalian reservoirs, including the human-specific pathogens Bartonella quintana and Bartonella bacilliformis that cause trench fever and Oroya fever, respectively. Here, we have identified bacterial factors that mediate host-specific erythrocyte colonization in the mammalian reservoirs. Using mouse-specific Bartonella birtlesii, human-specific Bartonella quintana, cat-specific Bartonella henselae and rat-specific Bartonella tribocorum, we established in vitro adhesion and invasion assays with isolated erythrocytes that fully reproduce the host-specificity of erythrocyte infection as observed in vivo. By signature-tagged mutagenesis of B. birtlesii and mutant selection in a mouse infection model we identified mutants impaired in establishing intraerythrocytic bacteremia. Among 45 abacteremic mutants, five failed to adhere to and invade mouse erythrocytes in vitro. The corresponding genes encode components of the type IV secretion system (T4SS) Trw, demonstrating that this virulence factor laterally acquired by the Bartonella lineage is directly involved in adherence to erythrocytes. Strikingly, ectopic expression of Trw of rat-specific B. tribocorum in cat-specific B. henselae or human-specific B. quintana expanded their host range for erythrocyte infection to rat, demonstrating that Trw mediates host-specific erythrocyte infection. A molecular evolutionary analysis of the trw locus further indicated that the variable, surface-located TrwL and TrwJ might represent the T4SS components that determine host-specificity of erythrocyte parasitism. In conclusion, we show that the laterally acquired Trw T4SS diversified in the Bartonella lineage to facilitate host

Comparison of optomagnetic and AC susceptibility readouts in a magnetic nanoparticle agglutination assay for detection of C-reactive protein.

PubMed

Fock, Jeppe; Parmvi, Mattias; Strömberg, Mattias; Svedlindh, Peter; Donolato, Marco; Hansen, Mikkel Fougt

2017-02-15

There is an increasing need to develop biosensor methods that are highly sensitive and that can be combined with low-cost consumables. The use of magnetic nanoparticles (MNPs) is attractive because their detection is compatible with low-cost disposables and because application of a magnetic field can be used to accelerate assay kinetics. We present the first study and comparison of the performance of magnetic susceptibility measurements and a newly proposed optomagnetic method. For the comparison we use the C-reactive protein (CRP) induced agglutination of identical samples of 100nm MNPs conjugated with CRP antibodies. Both methods detect agglutination as a shift to lower frequencies in measurements of the dynamics in response to an applied oscillating magnetic field. The magnetic susceptibility method probes the magnetic response whereas the optomagnetic technique probes the modulation of laser light transmitted through the sample. The two techniques provided highly correlated results upon agglutination when they measure the decrease of the signal from the individual MNPs (turn-off detection strategy), whereas the techniques provided different results, strongly depending on the read-out frequency, when detecting the signal due to MNP agglomerates (turn-on detection strategy). These observations are considered to be caused by differences in the volume-dependence of the magnetic and optical signals from agglomerates. The highest signal from agglomerates was found in the optomagnetic signal at low frequencies. Copyright © 2016 Elsevier B.V. All rights reserved.

Augmented water binding and low cellular water content in erythrocytes of camel and camelids.

PubMed Central

Bogner, P; Csutora, P; Cameron, I L; Wheatley, D N; Miseta, A

1998-01-01

We investigated a link between hemoglobin primary structure, hemoglobin hydrophobicity-hydrophilicity, and erythrocyte water content in various mammalian species. Some hemoglobin molecules, particularly those of the camel and camelids, contain more charged amino acid residues and are more hydrophilic than the hemoglobins of human and a number of other mammalian species. To test the in vivo significance of these alterations of hemoglobin primary structure, we determined the osmotically unresponsive erythrocyte water fractions in mannit solutions of various osmolarities at 4 degreesC. Among the species investigated, the size of the osmotically unresponsive erythrocyte water fraction relates in a positive linear way to hemoglobin hydrophilicity. The extreme low total erythrocyte water content of camel erythrocytes (1.1-1.3 g water/g dry mass) may be explained by a comparatively high osmotically unresponsive erythrocyte water fraction. It is proposed that alterations of hemoglobin sequences of camel and camelids may be the part of a natural selection process aimed at protecting these animals against osmotic dehydration in arid environments. PMID:9826628

A novel approach for assessments of erythrocyte sedimentation rate.

PubMed

Pribush, A; Hatskelzon, L; Meyerstein, N

2011-06-01

Previous studies have shown that the dispersed phase of sedimenting blood undergoes dramatic structural changes: Discrete red blood cell (RBC) aggregates formed shortly after a settling tube is filled with blood are combined into a continuous network followed by its collapse via the formation of plasma channels, and finally, the collapsed network is dispersed into individual fragments. Based on this scheme of structural transformation, a novel approach for assessments of erythrocyte sedimentation is suggested. Information about erythrocyte sedimentation is extracted from time records of the blood conductivity measured after a dispersion of RBC network into individual fragments. It was found that the sedimentation velocity of RBC network fragments correlates positively with the intensity of attractive intercellular interactions, whereas no effect of hematocrit (Hct) was observed. Thus, unlike Westergren erythrocyte sedimentation rate, sedimentation data obtained by the proposed method do not require correction for Hct. © 2010 Blackwell Publishing Ltd.

Possible interaction between myxomatosis and calicivirosis related to rabbit haemorrhagic disease affecting the European rabbit.

PubMed

Marchandeau, S; Bertagnoli, S; Peralta, B; Boucraut-Baralon, C; Letty, J; Reitz, F

2004-11-06

Serological data on myxoma virus, rabbit haemorrhagic disease (RHD) virus and RHD-like viruses in juvenile rabbits (Oryctolagus cuniculus) trapped in 1995, 1996 and 1997 in two areas of France were analysed. For each disease, the effects of bodyweight, year, month and seropositivity for the other disease were modelled by using logistic regressions. In one area, a model including RHD seropositivity was selected to explain the myxoma virus seropositivity. Models including myxoma virus seropositivity were selected to explain the RHD seropositivity in both areas, and the odds of a rabbit being seropositive to both viruses were 5.1 and 8.4 times higher than the odds of a rabbit being seronegative to myxoma virus and seropositive to RHD. The year and bodyweight had significant effects for myxomatosis in one area and for RHD in both areas.

A survey of fur mites in domestic rabbits.

PubMed

Flatt, R E; Wiemers, J

1976-10-01

A survey of six commercial rabbit colonies was conducted to determine the prevalence of the mite Cheyletiella parasitvorax. This mite was present in all six colonies, and 43.2% of 220 rabbits examined were infested. Listrophorus gibbus, reported only once previously in domestic rabbits in the United States, was found in four of the six colonies, and in 7.3% of the 220 rabbits examined. Non-parasitic mites were found in 3.2% of the samples. Over 50% of the rabbits examined had inapparent mite infestations.

Phenotypic variations in osmotic lysis of Sahel goat erythrocytes in non-ionic glucose media.

PubMed

Igbokwe, Nanacha Afifi; Igbokwe, Ikechukwu Onyebuchi

2016-03-01

Erythrocyte osmotic lysis in deionised glucose media is regulated by glucose influx, cation efflux, and changes in cell volume after water diffusion. Transmembrane fluxes may be affected by varied expression of glucose transporter protein and susceptibility of membrane proteins to glucose-induced glycosylation and oxidation in various physiologic states. Variations in haemolysis of Sahel goat erythrocytes after incubation in hyposmotic non-ionic glucose media, associated with sex, age, late pregnancy, and lactation, were investigated. The osmotic fragility curve in glucose media was sigmoidal with erythrocytes from goats in late pregnancy (PRE) or lactation (LAC) or from kid (KGT) or middle-aged (MGT) goats. Non-sigmoidal phenotype occurred in yearlings (YGT) and old (OGT) goats. The composite fragility phenotype for males and non-pregnant dry (NPD) females was non-sigmoidal. Erythrocytes with non-sigmoidal curves were more stable than those with sigmoidal curves because of inflectional shift of the curve to the left. Erythrocytes tended to be more fragile with male than female sex, KGT and MGT than YGT and OGT, and LAC and PRE than NPD. Thus, sex, age, pregnancy, and lactation affected the haemolytic pattern of goat erythrocytes in glucose media. The physiologic state of the goat affected the in vitro interaction of glucose with erythrocytes, causing variations in osmotic stability with variants of fragility phenotype. Variations in the effect of high extracellular glucose concentrations on the functions of membrane-associated glucose transporter, aquaporins, and the cation cotransporter were presumed to be relevant in regulating the physical properties of goat erythrocytes under osmotic stress.

Erythrocyte aggregation under high pressure studied by laser photometry and mathematical analysis.

PubMed

Toyama, Yoshiharu; Yoshida, Hisashi; Yamamoto, Takao; Dobashi, Toshiaki

2016-04-01

The effects of hydrostatic pressure on erythrocyte aggregation have been studied by laser photometry and analysis based on a phenomenological theory. Samples were prepared by suspending swine erythrocytes in their own plasma. A high-pressure vessel consisting of a stainless-steel block with a hole to hold a sample cell and two sapphire windows to allows the passage of a He-Ne laser beam was used in the experimental setup. The suspension was stirred at 1500 rpm to disperse the erythrocytes homogeneously. Immediately after reducing the stirring rate from 1500 rpm to 300 rpm, the transmitted light intensity (I) was recorded every 10 ms under a high pressure of 40-200 MPa. The value of I increased with time (t) owing to erythrocyte aggregation. From the phenomenological theory, the equation ΔI(t)=ΔIeq[1-e(-Kt)/(1-B(1-e(-Kt)))] was derived for the change in the transmitted light intensity (ΔI) due to erythrocyte aggregation, where ΔIeq is the transmitted light intensity in the steady state, K is a time constant and B is a constant that represents the ratio of the number of interaction sites on erythrocyte aggregates at time t to that in the steady state. The observed time courses of ΔI obtained at all pressures could be closely fitted to the theoretical equation. ΔIeq roughly increased with increasing pressure. On the other hand, K and B abruptly decreased above 120 MPa. The growth rate of aggregates decreased above 120 MPa. These results suggest a change in the mechanism of erythrocyte aggregation at approximately 120 MPa. We discuss the physical meaning of the parameters. Copyright © 2015 Elsevier B.V. All rights reserved.

Direct measurement of erythrocyte deformability in diabetes mellitus with a transparent microchannel capillary model and high-speed video camera system.

PubMed

Tsukada, K; Sekizuka, E; Oshio, C; Minamitani, H

2001-05-01

To measure erythrocyte deformability in vitro, we made transparent microchannels on a crystal substrate as a capillary model. We observed axisymmetrically deformed erythrocytes and defined a deformation index directly from individual flowing erythrocytes. By appropriate choice of channel width and erythrocyte velocity, we could observe erythrocytes deforming to a parachute-like shape similar to that occurring in capillaries. The flowing erythrocytes magnified 200-fold through microscopy were recorded with an image-intensified high-speed video camera system. The sensitivity of deformability measurement was confirmed by comparing the deformation index in healthy controls with erythrocytes whose membranes were hardened by glutaraldehyde. We confirmed that the crystal microchannel system is a valuable tool for erythrocyte deformability measurement. Microangiopathy is a characteristic complication of diabetes mellitus. A decrease in erythrocyte deformability may be part of the cause of this complication. In order to identify the difference in erythrocyte deformability between control and diabetic erythrocytes, we measured erythrocyte deformability using transparent crystal microchannels and a high-speed video camera system. The deformability of diabetic erythrocytes was indeed measurably lower than that of erythrocytes in healthy controls. This result suggests that impaired deformability in diabetic erythrocytes can cause altered viscosity and increase the shear stress on the microvessel wall. Copyright 2001 Academic Press.

PUFA levels in erythrocyte membrane phospholipids are differentially associated with colorectal adenoma risk.

PubMed

Rifkin, Samara B; Shrubsole, Martha J; Cai, Qiuyin; Smalley, Walter E; Ness, Reid M; Swift, Larry L; Zheng, Wei; Murff, Harvey J

2017-06-01

Dietary intake of PUFA has been associated with colorectal neoplasm risk; however, results from observational studies have been inconsistent. Most prior studies have utilised self-reported dietary measures to assess fatty acid exposure which might be more susceptible to measurement error and biases compared with biomarkers. The purpose of this study was to determine whether erythrocyte phospholipid membrane PUFA percentages are associated with colorectal adenoma risk. We included data from 904 adenoma cases and 835 polyp-free controls who participated in the Tennessee Colorectal Polyp Study, a large colonoscopy-based case-control study. Erythrocyte membrane PUFA percentages were measured using GC. Conditional logistic regression was used to calculate adjusted OR for risk of colorectal adenomas with erythrocyte membrane PUFA. Higher erythrocyte membrane percentages of arachidonic acid was associated with an increased risk of colorectal adenomas (adjusted OR 1·66; 95 % CI 1·05, 2·62, P trend=0·02) comparing the highest tertile to the lowest tertile. The effect size for arachidonic acid was more pronounced when restricting the analysis to advanced adenomas only. Higher erythrocyte membrane EPA percentages were associated with a trend towards a reduced risk of advanced colorectal adenomas (P trend=0·05). Erythrocyte membrane arachidonic acid percentages are associated with an increased risk of colorectal adenomas.

Tirilazad mesylate protects stored erythrocytes against osmotic fragility.

PubMed

Epps, D E; Knechtel, T J; Bacznskyj, O; Decker, D; Guido, D M; Buxser, S E; Mathews, W R; Buffenbarger, S L; Lutzke, B S; McCall, J M

1994-12-01

The hypoosmotic lysis curve of freshly collected human erythrocytes is consistent with a single Gaussian error function with a mean of 46.5 +/- 0.25 mM NaCl and a standard deviation of 5.0 +/- 0.4 mM NaCl. After extended storage of RBCs under standard blood bank conditions the lysis curve conforms to the sum of two error functions instead of a possible shift in the mean and a broadening of a single error function. Thus, two distinct sub-populations with different fragilities are present instead of a single, broadly distributed population. One population is identical to the freshly collected erythrocytes, whereas the other population consists of osmotically fragile cells. The rate of generation of the new, osmotically fragile, population of cells was used to probe the hypothesis that lipid peroxidation is responsible for the induction of membrane fragility. If it is so, then the antioxidant, tirilazad mesylate (U-74,006f), should protect against this degradation of stored erythrocytes. We found that tirilazad mesylate, at 17 microM (1.5 mol% with respect to membrane lecithin), retards significantly the formation of the osmotically fragile RBCs. Concomitantly, the concentration of free hemoglobin which accumulates during storage is markedly reduced by the drug. Since the presence of the drug also decreases the amount of F2-isoprostanes formed during the storage period, an antioxidant mechanism must be operative. These results demonstrate that tirilazad mesylate significantly decreases the number of fragile erythrocytes formed during storage in the blood bank.

[Comparison of long-chain polyunsaturated fatty acids in plasma and erythrocyte phospholipids for biological monitoring].

PubMed

Kawabata, Terue; Nakai, Kunihiko; Hagiwara, Chie; Kurokawa, Naoyuki; Murata, Katsuyuki; Yaginuma, Kozue; Satoh, Hiroshi

2011-01-01

Previous data have indicated that the erythrocyte membrane may be the preferred sample type for assessing long-chain polyunsaturated fatty acid (LCPUFA) contents in cardiac and cerebral membranes. In this epidemiological study, we examined whether plasma phospholipids can be used for accurate biological monitoring of the LCPUFA state or whether analysis of erythrocyte membrane phospholipids is indispensable. (1) The analysis of LCPUFA contents in erythrocyte membrane phospholipids was conducted at baseline and after 1 and 3 days at 4°C, and 21 days at -40°C, after blood drawing, and the changes in LCPUFA content were examined. (2) The LCPUFA compositions of plasma and erythrocyte phospholipids in 133 young women (18-30 years old) were examined and the relationships between the sample type and the levels of LCPUFAs were determined. Eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and DHA/arachidonic acid (AA) and (EPA+DHA)/AA ratios in erythrocyte membrane phospholipids after 21 days of blood drawing significantly decreased compared with the corresponding baseline data. Regarding AA, EPA and DHA, a significant positive correlation was shown between levels of erythrocyte membrane phospholipids and plasma phospholipids (AA, r=0.364; EPA, r=0.709; DHA, r=0.653). The predictive value of plasma phospholipids for determining the highest concentration quartile in erythrocyte phospholipids was better in EPA (70%) than in DHA (55%) and AA (42%). The measurement of LCPUFA content in erythrocyte membrane phospholipids is necessary for accurate biological monitoring. We also found that LCPUFA in erythrocyte membrane phospholipids is stable in cold storage (4°C) for 3 days after blood drawing.

Identification of erythrocyte membrane proteins interacting with Mycoplasma suis GAPDH and OSGEP.

PubMed

Song, Qiqi; Song, Weijiao; Zhang, Weijing; He, Lan; Fang, Rui; Zhou, Yanqin; Shen, Bang; Hu, Min; Zhao, Junlong

2018-05-05

Mycoplasma suis (M. suis) is an uncultivable haemotrophic mycoplasma that parasitizes the red blood cells of a wide range of domestic and wild animals. Adhesion of M. suis to host erythrocytes is crucial for its unique RBC-dependent lifecycle. MSG1 protein (now named as GAPDH) with homology to glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was the first identified adhesion protein of M. suis. In this study, we found that O-sialoglycoprotein endopeptidase (OSGEP) is another M. suis protein capable of binding porcine erythrocytes. Recombinant OSGEP expressed in E. coli demonstrated surface localization similar to GAPDH. Purified rOSGEP bound to erythrocyte membrane preparations in a dose-dependent manner and this adhesion could be specifically inhibited by anti-rOSGEP antibodies. E. coli transformants expressing OSGEP on their surface were able to adhere to porcine erythrocytes. Furthermore, using far-western and pull-down assays, we determined the host membrane proteins that interacted with OSGEP and GAPDH were Band3 and glycophorin A (GPA). In conclusion, our studies indicated that OSGEP and GAPDH could interact with both Band3 and GPA to mediate adhesion of M. suis to porcine erythrocytes. Copyright © 2018 Elsevier Ltd. All rights reserved.

Comparative studies on osmosis based encapsulation of sodium diclofenac in porcine and outdated human erythrocyte ghosts.

PubMed

Bukara, Katarina; Drvenica, Ivana; Ilić, Vesna; Stančić, Ana; Mišić, Danijela; Vasić, Borislav; Gajić, Radoš; Vučetić, Dušan; Kiekens, Filip; Bugarski, Branko

2016-12-20

The objective of our study was to develop controlled drug delivery system based on erythrocyte ghosts for amphiphilic compound sodium diclofenac considering the differences between erythrocytes derived from two readily available materials - porcine slaughterhouse and outdated transfusion human blood. Starting erythrocytes, empty erythrocyte ghosts and diclofenac loaded ghosts were compared in terms of the encapsulation efficiency, drug releasing profiles, size distribution, surface charge, conductivity, surface roughness and morphology. The encapsulation of sodium diclofenac was performed by an osmosis based process - gradual hemolysis. During this process sodium diclofenac exerted mild and delayed antihemolytic effect and increased potassium efflux in porcine but not in outdated human erythrocytes. FTIR spectra revealed lack of any membrane lipid disorder and chemical reaction with sodium diclofenac in encapsulated ghosts. Outdated human erythrocyte ghosts with detected nanoscale damages and reduced ability to shrink had encapsulation efficiency of only 8%. On the other hand, porcine erythrocyte ghosts had encapsulation efficiency of 37% and relatively slow drug release rate. More preserved structure and functional properties of porcine erythrocytes related to their superior encapsulation and release performances, define them as more appropriate for the usage in sodium diclofenac encapsulation process. Copyright © 2016 Elsevier B.V. All rights reserved.

Long-term physiological effects of enhanced O/sub 2/ release by inositol hexaphosphate-loaded erythrocytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Teisseire, B.; Ropars, C.; Villereal, M.C.

1987-10-01

A continuous lysing and resealing procedure with erythrocytes permitted incorporation in these cells of inositol hexaphosphate (InsP/sub 6/), a strong allosteric effector of Hb. This leads to significant rightward shifts of the HbO/sub 2/ dissociation curves with in vitro P/sub 50/, values increasing from 32.2 +/- 1.8 torr for control erythrocytes to 86 +/- 60 torr. The shape of the dissociation curve was still sigmoidal, although the Hill coefficient was decreased. The life span of InsP/sub 6/-loaded erythrocytes equaled that of control erythrocytes. Erythrocyte-survival studies were done using /sub 51/Cr labeling of cells. The long-term physiological effects of the InsP/submore » 6/-loaded erythrocytes on piglets were increased O/sub 2/ release and reduced cardiac output. The reduced O/sub 2/ affinity of the InsP/sub 6/-loaded erythrocytes was still effective 20 days after transfusion in awake piglets. The electrolyte concentration appeared stable over the 5-day observation period except for a transient, but significant, hyperkalemia immediately after transfusion. The reductions in the O/sub 2/ affinity of Hb reported here are large compared with previously reported values. Introduction of InsP/sub 6/ into viable erythrocytes improves tissue oxygenation when, for any reason, normal blood flow is impaired.« less

Action of Cortisol on Sodium Transport in Canine Erythrocytes

PubMed Central

Streeten, David H. P.; Moses, Arnold M.

1968-01-01

Incubation of blood from deoxycorticosterone-treated, adrenalectomized dogs with glucose, 22NaCl, and cortisol, added in vitro, revealed log dose-related acceleration of sodium influx, of glucose utilization, and of lactate formation by cortisol in concentrations between 150 and 1000 µg/liter. Addition of 2-deoxyglucose, or preincubation of the blood until blood glucose concentration had fallen below 2.0 mg per 100 ml, reduced or abolished the acceleratory action of added cortisol on sodium influx but had no effect on sodium influx in the absence of added cortisol. Cortisol did not change the ATP or ATPase content of erythrocytes, or the metabolism of glucose via the pentose phosphate pathway, or the rate of efflux of 22Na from the erythrocytes. The acceleratory actions of cortisol on sodium, influx, glucose utilization, and lactate formation were significantly correlated. Cortisol (1000 µg/liter) enhanced sodium influx by approximately 8.7 mmole per liter erythrocytes per hour for each 1 mmole cortisol-induced increment in ATP production. It is concluded that sodium influx in canine erythrocytes comprises a passive component, unchanged by cellular metabolism, and a second component which is accelerated and inhibited in proportion to prevailing plasma concentrations of cortisol and aldosterone, and which (for cortisol) depends upon accelerated ATP production via glycolysis. These steroid actions probably result from effects on enzyme activity rather than on new enzyme induction. PMID:4233676

Plasmodium falciparum: a simplified technique for obtaining singly infected erythrocytes.

PubMed

Puthia, Manoj K; Tan, Kevin S W

2005-02-01

We report the development of a simple technique involving 15 ml polypropylene tubes and a rotatory incubator for obtaining erythrocytes singly infected with Plasmodium falciparum. This technique will be useful for cloning of the parasite. Our finding that P. falciparum merozoite invasion is inhibited during rotation suggests that this method may also be useful for the study of parasite-erythrocyte interactions under dynamic circulatory conditions.

Hemoglobin degradation in malaria-infected erythrocytes determined from live cell magnetophoresis

PubMed Central

Moore, Lee R.; Fujioka, Hisashi; Williams, P. Stephen; Chalmers, Jeffrey J.; Grimberg, Brian; Zimmerman, Peter; Zborowski, Maciej

2013-01-01

During intra-erythrocytic development, malaria trophozoites digest hemoglobin, which leads to parasite growth and asexual replication while accumulating toxic heme. To avoid death, the parasite synthesizes insoluble hemozoin crystals in the digestive vacuole through polymerization of β-hematin dimers. In the process, the heme is converted to a high-spin ferriheme whose magnetic properties were studied as early as 1936 by Pauling et al. Here, by magnetophoretic cell motion analysis, we provide evidence for a graduated increase of live cell magnetic susceptibility with developing blood-stage parasites, compatible with the increase in hemozoin content and the mechanism used by P. falciparum to avoid heme toxicity. The measured magnetophoretic mobility of the erythrocyte infected with a late-stage schizont form was m = 2.94 × 10−6 mm3 s/kg, corresponding to the net volume magnetic susceptibility (relative to water) of Δχ = 1.80 × 10−6, significantly higher than that of the oxygenated erythrocyte (−0.18×10−6) but lower than that of the fully deoxygenated erythrocyte (3.33×10−6). The corresponding fraction of hemoglobin converted to hemozoin, calculated based on the known magnetic susceptibilities of hemoglobin heme and hemozoin ferriheme, was 0.50, in agreement with the published biochemical and crystallography data. Magnetophoretic analysis of live erythrocytes could become significant for antimalarial drug susceptibility and resistance determination. PMID:16461330

Erythrocyte-derived optical nano-vesicles as theranostic agents

NASA Astrophysics Data System (ADS)

Mac, Jenny T.; Nunez, Vicente; Bahmani, Baharak; Guerrero, Yadir; Tang, Jack; Vullev, Valentine I.; Anvari, Bahman

2015-07-01

We have engineered nano-vesicles, derived from erythrocytes, which can be doped with various near infrared (NIR) organic chromophores, including the FDA-approved indocyanine green (ICG). We refer to these vesicles as NIR erythrocyte-mimicking transducers (NETS) since in response to NIR photo-excitation they can generate heat or emit fluorescent light. Using biochemical methods based on reduction amination, we have functionalized the surface of NET with antibodies to target specific biomolecules. We present results that demonstrate the effectiveness of NETs in targeted imaging of cancer cells that over-express the human epidermal growth factor receptor-2 (HER2).

Erythrocyte Stiffness during Morphological Remodeling Induced by Carbon Ion Radiation

PubMed Central

Zhang, Baoping; Liu, Bin; Zhang, Hong; Wang, Jizeng

2014-01-01

The adverse effect induced by carbon ion radiation (CIR) is still an unavoidable hazard to the treatment object. Thus, evaluation of its adverse effects on the body is a critical problem with respect to radiation therapy. We aimed to investigate the change between the configuration and mechanical properties of erythrocytes induced by radiation and found differences in both the configuration and the mechanical properties with involving in morphological remodeling process. Syrian hamsters were subjected to whole-body irradiation with carbon ion beams (1, 2, 4, and 6 Gy) or X-rays (2, 4, 6, and 12 Gy) for 3, 14 and 28 days. Erythrocytes in peripheral blood and bone marrow were collected for cytomorphological analysis. The mechanical properties of the erythrocytes were determined using atomic force microscopy, and the expression of the cytoskeletal protein spectrin-α1 was analyzed via western blotting. The results showed that dynamic changes were evident in erythrocytes exposed to different doses of carbon ion beams compared with X-rays and the control (0 Gy). The magnitude of impairment of the cell number and cellular morphology manifested the subtle variation according to the irradiation dose. In particular, the differences in the size, shape and mechanical properties of the erythrocytes were well exhibited. Furthermore, immunoblot data showed that the expression of the cytoskeletal protein spectrin-α1 was changed after irradiation, and there was a common pattern among its substantive characteristics in the irradiated group. Based on these findings, the present study concluded that CIR could induce a change in mechanical properties during morphological remodeling of erythrocytes. According to the unique characteristics of the biomechanical categories, we deduce that changes in cytomorphology and mechanical properties can be measured to evaluate the adverse effects generated by tumor radiotherapy. Additionally, for the first time, the current study provides a new

Erythrocyte stiffness during morphological remodeling induced by carbon ion radiation.

PubMed

Zhang, Baoping; Liu, Bin; Zhang, Hong; Wang, Jizeng

2014-01-01

The adverse effect induced by carbon ion radiation (CIR) is still an unavoidable hazard to the treatment object. Thus, evaluation of its adverse effects on the body is a critical problem with respect to radiation therapy. We aimed to investigate the change between the configuration and mechanical properties of erythrocytes induced by radiation and found differences in both the configuration and the mechanical properties with involving in morphological remodeling process. Syrian hamsters were subjected to whole-body irradiation with carbon ion beams (1, 2, 4, and 6 Gy) or X-rays (2, 4, 6, and 12 Gy) for 3, 14 and 28 days. Erythrocytes in peripheral blood and bone marrow were collected for cytomorphological analysis. The mechanical properties of the erythrocytes were determined using atomic force microscopy, and the expression of the cytoskeletal protein spectrin-α1 was analyzed via western blotting. The results showed that dynamic changes were evident in erythrocytes exposed to different doses of carbon ion beams compared with X-rays and the control (0 Gy). The magnitude of impairment of the cell number and cellular morphology manifested the subtle variation according to the irradiation dose. In particular, the differences in the size, shape and mechanical properties of the erythrocytes were well exhibited. Furthermore, immunoblot data showed that the expression of the cytoskeletal protein spectrin-α1 was changed after irradiation, and there was a common pattern among its substantive characteristics in the irradiated group. Based on these findings, the present study concluded that CIR could induce a change in mechanical properties during morphological remodeling of erythrocytes. According to the unique characteristics of the biomechanical categories, we deduce that changes in cytomorphology and mechanical properties can be measured to evaluate the adverse effects generated by tumor radiotherapy. Additionally, for the first time, the current study provides a new

Aluminum Trichloride Induces Hypertension and Disturbs the Function of Erythrocyte Membrane in Male Rats.

PubMed

Zhang, Qiuyue; Cao, Zheng; Sun, Xudong; Zuang, Cuicui; Huang, Wanyue; Li, Yanfei

2016-05-01

Aluminum (Al) is the most abundant metal in the earth's crust. Al accumulates in erythrocyte and causes toxicity on erythrocyte membrane. The dysfunction of erythrocyte membrane is a potential risk to hypertension. The high Al content in plasma was associated with hypertension. To investigate the effect of AlCl3 on blood pressure and the function of erythrocyte membrane, the rats were intragastrically exposed to 0, 64(1/20 LD50), 128(1/10 LD50), and 256(1/5 LD50) mg/kg body weight AlCl3 in double distilled water for 120 days, respectively. Then, we determined the systolic and mean arterial blood pressures of rats, the osmotic fragility, the percentage of membrane proteins, the activities of Na(+)/K(+)-ATPase, Mg(2+)-ATPase, Ca(2+)-ATPase, catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GSH-pX), and malondialdehyde (MDA) content of the erythrocyte membrane in this experiment. The results showed that AlCl3 elevated the systolic and mean arterial blood pressure of rats, increased the osmotic fragility, decreased the percentage of membrane protein, inhibited the activities of Na(+)/K(+)-ATPase, Mg(2+)-ATPase, Ca(2+)-ATPase, CAT, SOD and GSH-pX, and increased the MDA content of erythrocyte membrane. These results indicate that AlCl3 may induce hypertension by disturbing the function of erythrocyte membrane.

SJL-1, a C-type lectin, acts as a surface defense molecule in Japanese sea cucumber, Apostichopus japonicus.

PubMed

Ono, Keisuke; Suzuki, Takuya Alan; Toyoshima, Youichi; Suzuki, Tomoya; Tsutsui, Shigeyuki; Odaka, Tomoyuki; Miyadai, Toshiaki; Nakamura, Osamu

2018-05-01

The surface defense molecules of aquatic invertebrates against infectious microorganisms have remained largely unexplored. In the present study, hemagglutinins were isolated from an extract of body surface layer of Japanese sea cucumber, Apostichopus japonicus, by affinity chromatography with fixed rabbit erythrocyte membranes. The N-terminal sequence of a 15-kDa agglutinin was almost identical with that of SJL-1, a C-type lectin formerly identified in this species. Because cDNA sequence and tissue distribution of SJL-1 have not been reported, we performed cDNA sequencing, gene expression analysis, and western blotting and immunohistochemical evaluation with anti-recombinant SJL-1 (rSJL-1) antibodies. The hemagglutinin gene was transcribed mainly in the integument, tentacles, and respiratory tree. Western blotting revealed that SJL-I is present in a body surface rinse, indicating that SJL-1 is secreted onto the body surface. SJL-1-positive cells scattered beneath the outermost layer of the integument were detected by immunohistochemistry. Furthermore, rSJL-1 agglutinated Gram-positive and Gram-negative bacteria, and yeast. These results indicate that SJL-1 acts as a surface defense molecule in A. japonicus. Copyright © 2018 Elsevier Ltd. All rights reserved.

Purification and partial characterization of a new mannose/glucose-specific lectin from Dialium guineense Willd seeds that exhibits toxic effect.

PubMed

Bari, Alfa U; Silva, Helton C; Silva, Mayara T L; Pereira Júnior, Francisco N; Cajazeiras, João B; Sampaio, Alexandre H; Leal, Rodrigo B; Teixeira, Edson H; Rocha, Bruno A M; Nascimento, Kyria S; Nagano, Celso S; Cavada, Benildo S

2013-08-01

A new mannose/glucose-specific lectin, named DigL, was purified from seeds of Dialium guineense by a single step using a Sepharose 4b-Mannose affinity chromatography column. DigL strongly agglutinated rabbit erythrocytes and was inhibited by d-mannose, d-glucose, and derived sugars, especially α-methyl-d-mannopyranoside and N-acetyl-d-glucosamine. DigL has been shown to be a stable protein, maintaining its hemagglutinating activity after incubation at a wide range of temperature and pH values and after incubation with EDTA. DigL is a glycoprotein composite by approximately 2.9% of carbohydrates by weight. By sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis, the purified DigL exhibited an electrophoretic profile consisting of a broad band of 28-30 kDa. Analysis using electrospray ionization mass spectrometry indicated that purified DigL possesses a molecular average mass of 28 452 ± 2 Da and shows the presence of possible glycoforms. In addition, DigL exhibited an intermediary toxic effect on Artemia sp. nauplii, and this effect was both dependent on native structure and mediated by a carbohydrate-binding site. Copyright © 2013 John Wiley & Sons, Ltd.

Insulin binding to erythrocytes after acute 16-methyleneprednisolone ingestion.

PubMed

Dwenger, A; Holle, W; Zick, R; Trautschold, I

1982-10-01

The binding of [125I]insulin to erythrocytes, glucose and insulin were determined before and 1, 7 and 35 days after ingestion of 2 X 60-methyleneprednisolone. None of two groups of volunteers (7 males, 4 females showed clear alterations of the insulin binding parameters (Ka and R0), or of the fasting cortisol, glucose and insulin concentrations. These results exclude the possibility that the diabetogenic effect of glucocorticoides is accompanied by an alteration of the insulin receptor characteristics of erythrocytes.

Detection of Salmonella enterica serovar Enteritidis (SE) Antibodies in Serum Using A Polystyrene Bead/SE Flagella Agglutination Assay

USDA-ARS?s Scientific Manuscript database

Serologic screening of flocks can be an important method to detect Salmonella enteritidis (SE) infections but can be labor intensive or lack specificity. Our goal was to develop a rapid agglutination assay using SE flagella adsorbed to polystyrene beads as a simple, relatively specific test to dete...

Increased virulence of Rabbit Haemorrhagic Disease Virus associated with genetic resistance in wild Australian rabbits (Oryctolagus cuniculus)

PubMed Central

Elsworth, Peter; Cooke, Brian D.; Kovaliski, John; Sinclair, Ronald; Holmes, Edward C.; Strive, Tanja

2015-01-01

The release of myxoma virus (MYXV) and Rabbit Haemorrhagic Disease Virus (RHDV) in Australia with the aim of controlling overabundant rabbits has provided a unique opportunity to study the initial spread and establishment of emerging pathogens, as well as their co-evolution with their mammalian hosts. In contrast to MYXV, which attenuated shortly after its introduction, rapid attenuation of RHDV has not been observed. By studying the change in virulence of recent field isolates at a single field site we show, for the first time, that RHDV virulence has increased through time, likely because of selection to overcome developing genetic resistance in Australian wild rabbits. High virulence also appears to be favoured as rabbit carcasses, rather than diseased animals, are the likely source of mechanical insect transmission. These findings not only help elucidate the co-evolutionary interaction between rabbits and RHDV, but reveal some of the key factors shaping virulence evolution. PMID:25146599

Evaluation of group A1B erythrocytes converted to type as group O: studies of markers of function and compatibility

PubMed Central

Gao, Hong-Wei; Zhuo, Hai-Long; Zhang, Xue; Ji, Shou-Ping; Tan, Ying-Xia; Li, Su-Bo; Jia, Yan-Jun; Xu, Hua; Wu, Qing-Fa; Yun, Zhi-Min; Luo, Qun; Gong, Feng

2016-01-01

Background Enzymatic conversion of blood group A1B red blood cells (RBC) to group O RBC (ECO) was achieved by combined treatment with α-galactosidase and α-N-acetylgalactosaminidase. The aim of this study was to evaluate the function and safety of these A1B-ECO RBC in vitro. Materials and methods A 20% packed volume of A1B RBC was treated with enzymes in 250 mM glycine buffer, pH 6.8. The efficiency of the conversion of A and B antigen was evaluated by traditional typing in test tubes, gel column agglutination technology and fluorescence-activated cell sorting (FACS) analysis. The physiological and metabolic parameters of native and ECO RBC were compared, including osmotic fragility, erythrocyte deformation index, levels of 2,3-diphosphoglycerate, ATP, methaemoglobin, free Na+, and free K+. The morphology of native and ECO RBC was observed by scanning electron microscopy. Residual α-galactosidase or α-N-acetylgalactosaminidase in A1B-ECO RBC was detected by double-antibody sandwich ELISA method. Manual cross-matching was applied to ensure blood compatibility. Results The RBC agglutination tests and FACS results showed that A1B RBC were efficiently converted to O RBC. Functional analysis suggested that the conversion process had little impact on the physiological and metabolic parameters of the RBC. The residual amounts of either α-galactosidase or α-N-acetylgalactosaminidase in the A1B-ECO RBC were less than 10 ng/mL of packed RBC. About 18% of group B and 55% of group O sera reacted with the A1B-ECO RBC in a sensitive gel column cross-matching test. Discussion The conversion process does not appear to affect the morphological, physiological or metabolic parameters of A1B-ECO RBC. However, the A1B-ECO RBC still reacted with some antigens. More research on group O and B sera, which may partly reflect the complexity of group A1 the safety of A1B-ECO RBC is necessary before the application of these RBC in clinical transfusion. PMID:26509826

Membrane transport in the malaria parasite and its host erythrocyte.

PubMed

Kirk, Kiaran; Lehane, Adele M

2014-01-01

As it grows and replicates within the erythrocytes of its host the malaria parasite takes up nutrients from the extracellular medium, exports metabolites and maintains a tight control over its internal ionic composition. These functions are achieved via membrane transport proteins, integral membrane proteins that mediate the passage of solutes across the various membranes that separate the biochemical machinery of the parasite from the extracellular environment. Proteins of this type play a key role in antimalarial drug resistance, as well as being candidate drug targets in their own right. This review provides an overview of recent work on the membrane transport biology of the malaria parasite-infected erythrocyte, encompassing both the parasite-induced changes in the membrane transport properties of the host erythrocyte and the cell physiology of the intracellular parasite itself.

A case of low success of blind vaccination campaigns against myxomatosis and rabbit haemorrhagic disease on survival of adult European wild rabbits.

PubMed

Rouco, Carlos; Moreno, Sacramento; Santoro, Simone

2016-10-01

Vaccination campaigns against myxomatosis and rabbit haemorrhagic disease (RHD) are commonly used in translocation programs conducted for the purpose of recovering wild European rabbit populations in Iberian Mediterranean ecosystems. In most cases rabbits are vaccinated 'blind' (i.e. without assessing their prior immunological status) for economic and logistic reasons. However, there is conflicting evidence on the effectiveness of such an approach. We tested whether blind vaccination against myxomatosis and rabbit haemorrhagic disease improved rabbit survival in a rabbit translocation program where wild rabbits were kept in semi-natural conditions in three enclosures. We conducted nine capture sessions over two years (2008-2010) and used the information collected to compare the survival of vaccinated (n=511) versus unvaccinated (n=161) adult wild rabbits using capture-mark-recapture analysis. Average monthly survival was no different for vaccinated versus unvaccinated individuals, both in the period between release and first capture (short-term) and after the first capture onward (long-term). Rabbit survival was lower in the short term than in the long term regardless of whether rabbits were vaccinated or not. Lower survival in the short-term could be due to the stress induced by the translocation process itself (e.g. handling stress). However, we did not find any overall effect of vaccination on survival which could be explained by two non-exclusive reasons. First, interference of the vaccine with the natural antibodies in the donor population. Due to donor populations have high density of rabbits with, likely, high prevalence of antibodies as a result of previous natural exposure to these diseases. Second, the lack of severe outbreaks during the study period. Based on our findings we argue that blind vaccination of adult rabbits in translocation programs may be often mostly ineffective and unnecessarily costly. In particular, since outbreaks are hard to predict

Gene Targeting in Rabbits: Single-Step Generation of Knock-out Rabbits by Microinjection of CRISPR/Cas9 Plasmids.

PubMed

Kawano, Yoshihiro; Honda, Arata

2017-01-01

The development of genome editing technology has allowed gene disruptions to be achieved in various animal species and has been beneficial to many mammals. Gene disruption using pluripotent stem cells is difficult to achieve in rabbits, but thanks to advances in genome editing technology, a number of gene disruptions have been conducted. This paper describes a simple and easy method for carrying out gene disruptions in rabbits using CRISPR/Cas9 in which the gene to be disrupted is marked, the presence or absence of off-target candidates is checked, and a plasmid allowing simultaneous expression of Cas9 and sgRNA is constructed. Next, the cleaving activity of candidate sequences is investigated, and assessments are carried out to determine whether the target sequences can be cut. Female rabbits subjected to superovulation treatment are mated with male rabbits and fertilized eggs are collected, and then pronuclear injection of plasmid DNA is performed. The next day, the two-cell stage embryos are transplanted into pseudopregnant rabbits, and offspring are born within approximately 29-30 days. The genomic DNA of the offspring is then examined to check what types of genetic modifications have occurred. With the advent of CRISPR/Cas9, the accessibility of gene disruptions in rabbits has improved remarkably. This paper summarizes specifically how to carry out gene disruptions in rabbits.

New insights on the regulation of the adenine nucleotide pool of erythrocytes in mouse models

PubMed Central

O’Brien, William G.; Ling, Han Shawn; Lee, Cheng Chi

2017-01-01

The observation that induced torpor in non-hibernating mammals could result from an increased AMP concentration in circulation led our investigation to reveal that the added AMP altered oxygen transport of erythrocytes. To further study the effect of AMP in regulation of erythrocyte function and systemic metabolism, we generated mouse models deficient in key erythrocyte enzymes in AMP metabolism. We have previously reported altered erythrocyte adenine nucleotide levels corresponding to altered oxygen saturation in mice deficient in both CD73 and AMPD3. Here we further investigate how these Ampd3-/-/Cd73-/- mice respond to the administered dose of AMP in comparison with the control models of single enzyme deficiency and wild type. We found that Ampd3-/-/Cd73-/- mice are more sensitive to AMP-induced hypometabolism than mice with a single enzyme deficiency, which are more sensitive than wild type. A dose-dependent rightward shift of erythrocyte p50 values in response to increasing amounts of extracellular AMP was observed. We provide further evidence for the direct uptake of AMP by erythrocytes that is insensitive to dipyridamole, a blocker for ENT1. The uptake of AMP by the erythrocytes remained linear at the highest concentration tested, 10mM. We also observed competitive inhibition of AMP uptake by ATP and ADP but not by the other nucleotides and metabolites tested. Importantly, our studies suggest that AMP uptake is associated with an erythrocyte ATP release that is partially sensitive to inhibition by TRO19622 and Ca++ ion. Taken together, our study suggests a novel mechanism by which erythrocytes recycle and maintain their adenine nucleotide pool through AMP uptake and ATP release. PMID:28746349

New insights on the regulation of the adenine nucleotide pool of erythrocytes in mouse models.

PubMed

O'Brien, William G; Ling, Han Shawn; Zhao, Zhaoyang; Lee, Cheng Chi

2017-01-01

The observation that induced torpor in non-hibernating mammals could result from an increased AMP concentration in circulation led our investigation to reveal that the added AMP altered oxygen transport of erythrocytes. To further study the effect of AMP in regulation of erythrocyte function and systemic metabolism, we generated mouse models deficient in key erythrocyte enzymes in AMP metabolism. We have previously reported altered erythrocyte adenine nucleotide levels corresponding to altered oxygen saturation in mice deficient in both CD73 and AMPD3. Here we further investigate how these Ampd3-/-/Cd73-/- mice respond to the administered dose of AMP in comparison with the control models of single enzyme deficiency and wild type. We found that Ampd3-/-/Cd73-/- mice are more sensitive to AMP-induced hypometabolism than mice with a single enzyme deficiency, which are more sensitive than wild type. A dose-dependent rightward shift of erythrocyte p50 values in response to increasing amounts of extracellular AMP was observed. We provide further evidence for the direct uptake of AMP by erythrocytes that is insensitive to dipyridamole, a blocker for ENT1. The uptake of AMP by the erythrocytes remained linear at the highest concentration tested, 10mM. We also observed competitive inhibition of AMP uptake by ATP and ADP but not by the other nucleotides and metabolites tested. Importantly, our studies suggest that AMP uptake is associated with an erythrocyte ATP release that is partially sensitive to inhibition by TRO19622 and Ca++ ion. Taken together, our study suggests a novel mechanism by which erythrocytes recycle and maintain their adenine nucleotide pool through AMP uptake and ATP release.

Hematopoietic Protein-1 Regulates the Actin Membrane Skeleton and Membrane Stability in Murine Erythrocytes

PubMed Central

Chan, Maia M.; Wooden, Jason M.; Tsang, Mark; Gilligan, Diana M.; Hirenallur-S, Dinesh K.; Finney, Greg L.; Rynes, Eric; MacCoss, Michael; Ramirez, Julita A.; Park, Heon; Iritani, Brian M.

2013-01-01

Hematopoietic protein-1 (Hem-1) is a hematopoietic cell specific member of the WAVE (Wiskott-Aldrich syndrome verprolin-homologous protein) complex, which regulates filamentous actin (F-actin) polymerization in many cell types including immune cells. However, the roles of Hem-1 and the WAVE complex in erythrocyte biology are not known. In this study, we utilized mice lacking Hem-1 expression due to a non-coding point mutation in the Hem1 gene to show that absence of Hem-1 results in microcytic, hypochromic anemia characterized by abnormally shaped erythrocytes with aberrant F-actin foci and decreased lifespan. We find that Hem-1 and members of the associated WAVE complex are normally expressed in wildtype erythrocyte progenitors and mature erythrocytes. Using mass spectrometry and global proteomics, Coomassie staining, and immunoblotting, we find that the absence of Hem-1 results in decreased representation of essential erythrocyte membrane skeletal proteins including α- and β- spectrin, dematin, p55, adducin, ankyrin, tropomodulin 1, band 3, and band 4.1. Hem1−/− erythrocytes exhibit increased protein kinase C-dependent phosphorylation of adducin at Ser724, which targets adducin family members for dissociation from spectrin and actin, and subsequent proteolysis. Increased adducin Ser724 phosphorylation in Hem1−/− erythrocytes correlates with decreased protein expression of the regulatory subunit of protein phosphatase 2A (PP2A), which is required for PP2A-dependent dephosphorylation of PKC targets. These results reveal a novel, critical role for Hem-1 in the homeostasis of structural proteins required for formation and stability of the actin membrane skeleton in erythrocytes. PMID:23424621

NICOTINE METABOLISM IN PREGNANT AND NON-PREGNANT RABBITS

PubMed Central

Tutka, Piotr; Dempsey, Delia A.; Jacob, Peyton; Benowitz, Neal L.; Kroetz, Deanna L.

2010-01-01

Smoking remains a major public health concern during pregnancy and is associated with numerous adverse effects. Recently the clearance of nicotine (NIC) and cotinine (COT) was shown to be substantially increased in pregnant women compared to non-pregnant controls. The present study investigated the usefulness of the rabbit for studying the molecular basis for the observed changes in NIC and COT disposition during pregnancy. NIC was largely metabolized to COT in rabbit liver microsomes (approximately 50% of total metabolism) with significant amounts of nicotine-N’-oxide and nornicotine also being detected. The conversion of NIC to COT was also detected in rabbit placental and fetal liver microsomes albeit at only a fraction of the rate in adult rabbit liver microsomes. The major products of COT metabolism in rabbit liver microsomes were 5’-hydroxycotinine, cotinine-N’-oxide and norcotinine. Differences between human and rabbit liver were most apparent for COT, with the major human metabolite 3’-hydroxycotinine, being formed at only low levels in rabbit liver microsomes. Pregnancy had no effect on the metabolism of NIC or on the expression of CYP2A6 immunoreactive proteins in rabbit liver microsomes. These studies provide a complete quantitative assessment of NIC metabolism in rabbit liver microsomes and suggest that the rabbit may not be an appropriate animal model to study the effects of pregnancy on NIC and COT metabolism. However, a molecular understanding of these effects is essential for prediction of the pharmacological and toxicological consequences of smoking during pregnancy. PMID:18686186

Hemolytic activity of Fusobacterium necrophorum culture supernatants due to presence of phospholipase A and lysophospholipase.

PubMed

Abe, P M; Kendall, C J; Stauffer, L R; Holland, J W

1979-01-01

Culture supernatants of Fusobacterium necrophorum demonstrated hemolytic activity. The hemolysin(s), which was partially purified by ammonium sulfate precipitation, was temperature-dependent and heat labile. The spectrum of hemolytic activity against various erythrocytes included rabbit, human, and dog erythrocytes. Goats, sheep, and bovine erythrocytes showed only trace hemolysis. According to results of thin-layer chromatography, the hemolysin hydrolyzed rabbit erythrocyte phosphatidyl choline, phosphatidyl ethanolamine, lysophosphatidyl choline, and bovine phosphatidyl choline. Hydrolysis of egg yolk phosphatidyl choline, bovine phosphatidyl ethanolamine, cholesterol, 1,2-dipalmitin, 1,3-dipalmitin, sphingomyelin, or triolein was not detected by thin layer chromatography. A more sensitive procedure utilizing gas-liquid chromatography revealed that, of the substrates tested, the following were bein hydrolyzed: bovine and egg yolk phosphatidyl choline, lysophosphatidyl choline, alpha-palmito-beta-eleoyl-L-alpha lecithin and alpha-oleoyl-betal-palmitoyl-L-alpha lecithin. Substrates which were weakly hydrolyzed were bovine phosphatidyl ethanolamine, DL-alpha-hosphatidyl ethanolamine dipalmitoyl, 1,2-dipalmitin, 1,3-dipalmitin, and triolein.

Ablation of the Kell/Xk complex alters erythrocyte divalent cation homeostasis

PubMed Central

Rivera, Alicia; Kam, Siok Yuen; Ho, Mengfatt; Romero, Jose R.; Lee, Soohee

2012-01-01

XK is a putative transporter of unknown function that is ubiquitously expressed and linked through disulfide bonds to Kell protein, an endothelin-3 (ET-3)-converting enzyme. We generated three knockout (KO) mice that lacked either Xk, Kell or both proteins and characterized erythrocyte cation levels, transport and hematological parameters. Absence of Xk or Kell was accompanied by changes in erythrocyte K+, Mg2+, Na+ and Ca2+ transport that were associated with changes in mean cellular volume and corpuscular hemoglobin concentration mean. Baseline Ca2+-ATPase activity was undetected in erythrocytes from all three mouse types but was restored upon pre-incubation with ET-3. Consistent with these alterations in Ca2+ handling, we observed increased Gardos channel activity in Kel and Xk KO mice. In addition Kel deletion was associated with increased Mg2+ permeability while Xk deletion blocked Na/Mg exchanger activity. Our results provide evidence that cellular divalent cation regulation is functionally coupled to the Kell/XK system in erythrocytes and loss of this complex may contribute to acanthocytosis formation in McLeod syndrome. PMID:23122227

Influence of linearly polarized near-infrared irradiation on deformability of human stored erythrocytes.

PubMed

Yokoyama, Kozo; Sugiyama, Kazuna

2003-02-01

To investigate the influence of linearly polarized near-infrared irradiation using the Super Lizer trade mark on deformability of human erythrocytes. Not only low-powered laser but also linearly polarized near-infrared beams have some biostimulation effects on various tissues. There were some reports of erythrocyte deformability improved by low-powered He-Ne laser irradiation. Human erythrocyte samples stored for three weeks were adjusted to 30% hematocrit. Erythrocyte deformability presented as the filter filtration rate was measured. There was no difference of the filter filtration rate between control group without irradiation and the group of 125 mJ/cm(2) exposure level at a wavelength of 830 nm. However, the groups of 625 and 1,250 mJ/cm(2) exposure levels at a wavelength of 830 nm showed higher filter filtration rates compared to the control group. Linearly polarized near-infrared irradiation in a range of 625-1,250 mJ/cm(2) exposure level at a wavelength of 830 nm improved deformability of human stored erythrocytes.

Kinetic analysis of interactions of paraoxon and oximes with human, Rhesus monkey, swine, rabbit, rat and guinea pig acetylcholinesterase.

PubMed

Worek, Franz; Aurbek, Nadine; Wille, Timo; Eyer, Peter; Thiermann, Horst

2011-01-15

Previous in vitro studies showed marked species differences in the reactivating efficiency of oximes between human and animal acetylcholinesterase (AChE) inhibited by organophosphorus (OP) nerve agents. These findings provoked the present in vitro study which was designed to determine the inhibition, aging, spontaneous and oxime-induced reactivation kinetics of the pesticide paraoxon, serving as a model compound for diethyl-OP, and the oximes obidoxime, pralidoxime, HI 6 and MMB-4 with human, Rhesus monkey, swine, rabbit, rat and guinea pig erythrocyte AChE. Comparable results were obtained with human and monkey AChE. Differences between human, swine, rabbit, rat and guinea pig AChE were determined for the inhibition and reactivation kinetics. A six-fold difference of the inhibitory potency of paraoxon with human and guinea pig AChE was recorded while only moderate differences of the reactivation constants between human and animal AChE were determined. Obidoxime was by far the most effective reactivator with all tested species. Only minor species differences were found for the aging and spontaneous reactivation kinetics. The results of the present study underline the necessity to determine the inhibition, aging and reactivation kinetics in vitro as a basis for the development of meaningful therapeutic animal models, for the proper assessment of in vivo animal data and for the extrapolation of animal data to humans. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Alterations of erythrocyte rheology and cellular susceptibility in end stage renal disease: Effects of peritoneal dialysis.

PubMed

Ertan, Nesrin Zeynep; Bozfakioglu, Semra; Ugurel, Elif; Sinan, Mukaddes; Yalcin, Ozlem

2017-01-01

In this study, we investigated the effects of peritoneal dialysis on hemorheological and hematological parameters and their relations with oxidant and antioxidant status of uremic patients. Hemorheological parameters (erythrocyte deformability, erythrocyte aggregation, osmotic deformability, blood and plasma viscosity) were measured in patients with renal insufficiency undergoing peritoneal dialysis (PD) and volunteers. Erythrocyte deformability, osmotic deformability and aggregation in both autologous plasma and 3% dextran 70 were measured by laser diffraction ektacytometry. Enzyme activities of glutathione peroxidase, superoxide dismutase and catalase were studied in erythrocytes; lipid peroxidation was studied by measuring the amount of malondialdehyde in both erythrocytes and plasma samples. Blood viscosity at native hematocrit was significantly lower in PD patients at all measured shear rates compared to controls, but it was high in PD patients at corrected (45%) hematocrit. Erythrocyte deformability did not show any difference between the two groups. Osmotic deformability was significantly lower in PD patients compared to controls. Aggregation index values were significantly high in PD patients in plasma Catalase and glutathione peroxidase activities in erythrocytes were decreased in PD patients whereas superoxide dismutase activity was increased compared to controls. Malondialdehyde was significantly increased in erythrocytes and plasma samples of PD patients which also shows correlations with aggregation parameters. It has been concluded that erythrocytes in PD patients are more prone to aggregation and this tendency could be influenced by lipid peroxidation activity in patient's plasma. These results imply that uremic conditions, loss of plasma proteins and an increased risk of oxidative stress because of decreasing levels of antioxidant enzymes affect erythrocyte rheology during peritoneal dialysis. This level of distortion may have crucial effects

Standardization of stain used for diagnosing erythrocytic inclusion body syndrome (EIBS)

USGS Publications Warehouse

1987-01-01

Erythrocytic inclusion body syndrome (EIBS), a viral erythrocytic necrosis (VEN)-like disease, has been observed in several areas in the Northwest. This virus disease is clinically diagnosed by microscopic examination of blood smears for intracytoplasmic erythrocytic inclusion bodies. Fish biologists involved in EIBS diagnostic work have been using several types of hematological stains. It became apparent that standardization of the staining procedure was needed. Comparative tests were conducted on blood smears and kidney imprints with the following commonly used blood stains: (1) Leishman-Giesma, (2) Pinacyanol chloride, (3) Powell 's Giemsa, (4) Harleco's Giemsa, (5) Diff Quik differential stain, (6) Wright's.Pinacyanol chloride stain was found to be the most consistent. The following staining procedure is recommended.

GENETIC ANALYSIS OF THE AGGA LOCUS INVOLVED IN AGGLUTINATION ND ADHERENCE OF PSEUDOMONAS PUTIDA, A BENEFICIAL FLUORESCENT PSEUDOMONAD

EPA Science Inventory

An isolate of Pseudomonas putida, which rapidly adheres to plant roots is agglutinated by a glycoprotein from root surfaces. gglutination is presented and adherence to the root surface is diminished by Tn5 insertion in mutant 5123. wo cosmid clones from wild type P putida and 2.7...

Plasma lipids profile and erythrocytes system in patients with coronary heart disease

NASA Astrophysics Data System (ADS)

Malinova, Lidia I.; Simonenko, Georgy V.; Tuchin, Valery V.; Denisova, Tatyana P.

2006-08-01

Erythrocytes system study can provide a framework for detailed exploration of blood cell-cell and cell-vessel wall interactions, one of the key patterns in blood and vascular pathophysiology. Our objective was to explore erythrocytes system in patients with stable angina pectoris II f.c. (Canadian classification). The participants (N = 56, age 40 - 55 years) without obesity, glucose tolerance violations, lipid lowering drugs treating, heart failure of II and more functional classes (NYHA), coronary episode at least 6 months before study were involved in the study. Blood samples were incubated with glucose solutions of increasing concentrations (from 2.5% to 20% with 2.5% step) during 60 mm (36° C). In prepared blood smears erythrocyte's sizes were studied. Plasma total cholesterol, triglyceride and glucose levels were also measured. Received data were approximated by polynomials of high degree, with after going first and second derivations. Erythrocytes system "behavior" was studied by means of phase pattern constructing. By lipids levels all the patient were divided into five groups: 1) patients with normal lipids levels, 2) patients with borderline total cholesterol level, 3) patients with isolated hypercholesterolemia, 4) patients with isolated hypertriglyceridemia and 5) patients with combined hyperlipidemia. Erythrocytes size lowering process was of set of "stages", which characteristics differ significantly (p > 0.05) in all five groups. Their rate and acceleration characteristics allow us to detect type of lipid profile in patients. Erythrocyte system disturbing by glucose concentration increase show to be most resistant in group of patients with isolated hypercholesterolemia.

Structure of malaria invasion protein RH5 with erythrocyte basigin and blocking antibodies.

PubMed

Wright, Katherine E; Hjerrild, Kathryn A; Bartlett, Jonathan; Douglas, Alexander D; Jin, Jing; Brown, Rebecca E; Illingworth, Joseph J; Ashfield, Rebecca; Clemmensen, Stine B; de Jongh, Willem A; Draper, Simon J; Higgins, Matthew K

2014-11-20

Invasion of host erythrocytes is essential to the life cycle of Plasmodium parasites and development of the pathology of malaria. The stages of erythrocyte invasion, including initial contact, apical reorientation, junction formation, and active invagination, are directed by coordinated release of specialized apical organelles and their parasite protein contents. Among these proteins, and central to invasion by all species, are two parasite protein families, the reticulocyte-binding protein homologue (RH) and erythrocyte-binding like proteins, which mediate host-parasite interactions. RH5 from Plasmodium falciparum (PfRH5) is the only member of either family demonstrated to be necessary for erythrocyte invasion in all tested strains, through its interaction with the erythrocyte surface protein basigin (also known as CD147 and EMMPRIN). Antibodies targeting PfRH5 or basigin efficiently block parasite invasion in vitro, making PfRH5 an excellent vaccine candidate. Here we present crystal structures of PfRH5 in complex with basigin and two distinct inhibitory antibodies. PfRH5 adopts a novel fold in which two three-helical bundles come together in a kite-like architecture, presenting binding sites for basigin and inhibitory antibodies at one tip. This provides the first structural insight into erythrocyte binding by the Plasmodium RH protein family and identifies novel inhibitory epitopes to guide design of a new generation of vaccines against the blood-stage parasite.

Metabolomics-Based Elucidation of Active Metabolic Pathways in Erythrocytes and HSC-Derived Reticulocytes.

PubMed

Srivastava, Anubhav; Evans, Krystal J; Sexton, Anna E; Schofield, Louis; Creek, Darren J

2017-04-07

A detailed analysis of the metabolic state of human-stem-cell-derived erythrocytes allowed us to characterize the existence of active metabolic pathways in younger reticulocytes and compare them to mature erythrocytes. Using high-resolution LC-MS-based untargeted metabolomics, we found that reticulocytes had a comparatively much richer repertoire of metabolites, which spanned a range of metabolite classes. An untargeted metabolomics analysis using stable-isotope-labeled glucose showed that only glycolysis and the pentose phosphate pathway actively contributed to the biosynthesis of metabolites in erythrocytes, and these pathways were upregulated in reticulocytes. Most metabolite species found to be enriched in reticulocytes were residual pools of metabolites produced by earlier erythropoietic processes, and their systematic depletion in mature erythrocytes aligns with the simplification process, which is also seen at the cellular and the structural level. Our work shows that high-resolution LC-MS-based untargeted metabolomics provides a global coverage of the biochemical species that are present in erythrocytes. However, the incorporation of stable isotope labeling provides a more accurate description of the active metabolic processes that occur in each developmental stage. To our knowledge, this is the first detailed characterization of the active metabolic pathways of the erythroid lineage, and it provides a rich database for understanding the physiology of the maturation of reticulocytes into mature erythrocytes.

Protection against myxomatosis and rabbit viral hemorrhagic disease with recombinant myxoma viruses expressing rabbit hemorrhagic disease virus capsid protein.

PubMed

Bertagnoli, S; Gelfi, J; Le Gall, G; Boilletot, E; Vautherot, J F; Rasschaert, D; Laurent, S; Petit, F; Boucraut-Baralon, C; Milon, A

1996-08-01

Two myxoma virus-rabbit hemorrhagic disease virus (RHDV) recombinant viruses were constructed with the SG33 strain of myxoma virus to protect rabbits against myxomatosis and rabbit viral hemorrhagic disease. These recombinant viruses expressed the RHDV capsid protein (VP60). The recombinant protein, which is 60 kDa in size, was antigenic, as revealed by its reaction in immunoprecipitation with antibodies raised against RHDV. Both recombinant viruses induced high levels of RHDV- and myxoma virus-specific antibodies in rabbits after immunization. Inoculations by the intradermal route protected animals against virulent RHDV and myxoma virus challenges.

An experimental investigation of agglutinate melting mechanisms - Shocked mixtures of Apollo 11 and 16 soils

NASA Technical Reports Server (NTRS)

Simon, S. B.; Papike, J. J.; Horz, F.; See, T. H.

1986-01-01

Mixtures of chemically contrasting lunar soils have been shocked at pressures ranging from 18.2-62.0 GPa. Other than the generation of impact melts, modal and textural changes caused by shock include destruction of pore space and fused soil clasts and conversion of plagioclase to maskelynite. The loss of the fused soil component in these runs indicates that low agglutinate contents in shocked and/or compacted regolith breccias cannot be considered by themselves to be evidence of formation from immature regolith. From the petrographic and chemical data it appears that the impact glass formed mainly from the fine fraction and the fused soil component in the target, with relatively minor contributions from the other coarse clasts. The impact glasses exhibit the same chemical enrichments and depletions as their corresponding fine fractions and plot on or near a mixing line between the bulk and fine fraction of the soil in which they were formed. From this as well as several other studies it appears that the fusion of the finest fraction model is valid and that it accurately predicts the chemical systematics of impact glass formed from lunar soil. In addition, fusion of agglutinates present in the target soil is an important process.

Comparison of erythrocyte membrane fatty acid contents in renal transplant recipients and dialysis patients.

PubMed

Oh, J S; Kim, S M; Sin, Y H; Kim, J K; Park, Y; Bae, H R; Son, Y K; Nam, H K; Kang, H J; An, W S

2012-12-01

Alterations of erythrocyte membrane fatty acid (FA) composition play important roles in cellular function because they change the membrane microenvironment, including transmembrane receptors. The erythrocyte membrane oleic acid content is higher among patients with acute coronary syndrome and also in dialysis patients. However, available data are limited concerning erythrocyte membrane FA content in kidney transplant recipients (KTP). We sought to test the hypothesis that erythrocyte membrane FA content among KTP were different from those in dialysis patients. In this cross-sectional study, we recruited 35 hemodialysis, 33 peritoneal dialysis 49 KTP, and 33 normal control subjects (CTL). Their erythrocyte membrane FA content were measured by gas chromatography. The mean ages of the enrolled dialysis patients, KTP, and CTL were 56.4 ± 10.1, 48.9 ± 10.4, and 49.5 ± 8.3 years, respectively. Mean kidney transplant duration was 89.8 ± 64.8 months and mean dialysis duration, 49.0 ± 32.6 months. The intakes of vegetable lipid and vegetable protein including total calories were significantly increased among KTP versus dialysis patients. Total cholesterol (P < .001) and high density lipoprotein cholesterol (HDL; P < .001) levels were significantly higher and C-reactive protein was significantly lower among KTP compared with dialysis patients. The erythrocyte membrane content of palmitoleic acid (P < .001) was significantly higher but oleic acid (P < .001) significantly lower in KTP compared with dialysis patients. The erythrocyte membrane contents of arachidonic acid and docosahexaenoic acid were significantly higher, and linoleic acid and the omega-6 FA to omega-3 FA ratio (P < .001) significantly lower in KTP compared with dialysis patients. The erythrocyte membrane content of oleic acid was independently associated with monounsaturated fatty acid (beta = 0.771, P < .001), eicosapentaeonic acid (beta = -0.244, P = .010), and HDL (beta = -0.139, P = .049) in KTP. FA

Stimulation of Phospholipid Scrambling of the Erythrocyte Membrane by 9-Cis-Retinoic Acid.

PubMed

Abed, Majed; Alzoubi, Kousi; Lang, Florian; Al Mamun Bhuayn, Abdulla

2017-01-01

The endogenous retinoid 9-cis-retinoic acid has previously been shown to trigger apoptosis in a wide variety of cells including several tumor cells and has thus been suggested for the treatment of malignancy. Similar to apoptosis of nucleated cells, erythrocytes may enter suicidal erythrocyte death or eryptosis, which is characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Cellular mechanisms participating in the accomplishment of eryptosis include increase of cytosolic Ca2+ activity ([Ca2+]i) and formation of ceramide. The present study explored, whether 9-cis-retinoic acid induces eryptosis and whether the effect involves Ca2+ and/or ceramide. Flow cytometry was employed to estimate erythrocyte volume from forward scatter, phosphatidylserine exposure at the cell surface from annexin-V-binding, [Ca2+]i from Fluo3-fluorescence, and ceramide abundance utilizing specific antibodies. Hemolysis was quantified from hemoglobin concentration in the supernatant. A 48 hours exposure of human erythrocytes to 9-cis-retinoic acid (≥ 0.5 µg/ml) significantly increased the percentage of annexin-V-binding cells and significantly decreased forward scatter. Exposure to 9-cis-retinoic acid (≥ 0.5 µg/ml) significantly increased Fluo3-fluorescence, and the effect of 9-cis-retinoic acid on annexin-V-binding was significantly blunted by removal of extracellular Ca2+. Exposure to 9-cis-retinoic acid (1 µg/ml) further significantly increased the ceramide abundance at the erythrocyte surface and significantly increased hemolysis. 9-cis-retinoic acid triggers phospholipid scrambling of the erythrocyte cell membrane, an effect at least in part downstream of Ca2+ and ceramide. © 2017 The Author(s)Published by S. Karger AG, Basel.

Innate resistance to myxomatosis in wild rabbits in England.

PubMed

Ross, J; Sanders, M F

1977-12-01

Wild rabbits (Oryctolagus cuniculus) from one study area in England have been used over a period of 11 years to investigate the possible appearance of innate resistance to myxomatosis. Rabbits of 4-6 weeks old were captured alive, retained in the laboratory until at least 4 months old, and then infected with a type of myxoma virus which kills 90-95% of laboratory rabbits. Observations were made of symptoms, mortality rate and survival times.In the first 4 years of the study (1966-9), mortality rates were not significantly different from those of laboratory rabbits, although survival times of wild rabbits were appreciably longer. In 1970, the mortality rate amongst wild rabbits was 59%, in 1974 it was 17%, and in 1976 it was 20%, thus showing that a considerable degree of inherited resistance to myxomatosis has developed.The types of myxoma virus most commonly isolated from wild rabbits in Great Britain in recent years have been those which cause 70-95% mortality in laboratory rabbits. Therefore, if the degree of innate resistance demonstrated is widespread in Great Britain, there are serious implications regarding the size of the rabbit population, because myxomatosis has been an important factor in holding rabbit numbers at a relatively low level.

Innate resistance to myxomatosis in wild rabbits in England*

PubMed Central

Ross, J.; Sanders, M. F.

1977-01-01

Wild rabbits (Oryctolagus cuniculus) from one study area in England have been used over a period of 11 years to investigate the possible appearance of innate resistance to myxomatosis. Rabbits of 4-6 weeks old were captured alive, retained in the laboratory until at least 4 months old, and then infected with a type of myxoma virus which kills 90-95% of laboratory rabbits. Observations were made of symptoms, mortality rate and survival times. In the first 4 years of the study (1966-9), mortality rates were not significantly different from those of laboratory rabbits, although survival times of wild rabbits were appreciably longer. In 1970, the mortality rate amongst wild rabbits was 59%, in 1974 it was 17%, and in 1976 it was 20%, thus showing that a considerable degree of inherited resistance to myxomatosis has developed. The types of myxoma virus most commonly isolated from wild rabbits in Great Britain in recent years have been those which cause 70-95% mortality in laboratory rabbits. Therefore, if the degree of innate resistance demonstrated is widespread in Great Britain, there are serious implications regarding the size of the rabbit population, because myxomatosis has been an important factor in holding rabbit numbers at a relatively low level. PMID:270526

Parasite Sequestration in Plasmodium falciparum Malaria: Spleen and Antibody Modulation of Cytoadherence of Infected Erythrocytes

NASA Astrophysics Data System (ADS)

David, Peter H.; Hommel, Marcel; Miller, Louis H.; Udeinya, Iroka J.; Oligino, Lynette D.

1983-08-01

Sequestration, the adherence of infected erythrocytes containing late developmental stages of the parasite (trophozoites and schizonts) to the endothelium of capillaries and venules, is characteristic of Plasmodium falciparum infections. We have studied two host factors, the spleen and antibody, that influence sequestration of P. falciparum in the squirrel monkey. Sequestration of trophozoite/schizont-infected erythrocytes that occurs in intact animals is reduced in splenectomized animals; in vitro, when infected blood is incubated with monolayers of human melanoma cells, trophozoite/schizont-infected erythrocytes from intact animals but not from splenectomized animals bind to the melanoma cells. The switch in cytoadherence characteristics of the infected erythrocytes from nonbinding to binding occurs with a cloned parasite. Immune serum can inhibit and reverse in vitro binding to melanoma cells of infected erythrocytes from intact animals. Similarly, antibody can reverse in vivo sequestration as shown by the appearance of trophozoite/schizont-infected erythrocytes in the peripheral blood of an intact animal after inoculation with immune serum. These results indicate that the spleen modulates the expression of parasite alterations of the infected erythrocyte membrane responsible for sequestration and suggest that the prevention and reversal of sequestration could be one of the effector mechanisms involved in antibody-mediated protection against P. falciparum malaria.

Effects of phenylpropanolamine (PPA) on in vitro human erythrocyte membranes and molecular models

DOE Office of Scientific and Technical Information (OSTI.GOV)

Suwalsky, Mario, E-mail: msuwalsk@udec.cl; Zambrano, Pablo; Mennickent, Sigrid

Research highlights: {yields} PPA is a common ingredient in cough-cold medication and appetite suppressants. {yields} Reports on its effects on human erythrocytes are very scarce. {yields} We found that PPA induced in vitro morphological changes to human erythrocytes. {yields} PPA interacted with isolated unsealed human erythrocyte membranes. {yields} PPA interacted with class of lipid present in the erythrocyte membrane outer monolayer. -- Abstract: Norephedrine, also called phenylpropanolamine (PPA), is a synthetic form of the ephedrine alkaloid. After reports of the occurrence of intracranial hemorrhage and other adverse effects, including several deaths, PPA is no longer sold in USA and Canada.more » Despite the extensive information about PPA toxicity, reports on its effects on cell membranes are scarce. With the aim to better understand the molecular mechanisms of the interaction of PPA with cell membranes, ranges of concentrations were incubated with intact human erythrocytes, isolated unsealed human erythrocyte membranes (IUM), and molecular models of cell membranes. The latter consisted in bilayers built-up of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE), phospholipid classes present in the outer and inner monolayers of most plasmatic cell membranes, respectively. The capacity of PPA to perturb the bilayer structures of DMPC and DMPE was assessed by X-ray diffraction, DMPC large unilamellar vesicles (LUV) and IUM were studied by fluorescence spectroscopy, and intact human erythrocytes were observed by scanning electron microscopy (SEM). This study presents evidence that PPA affects human red cell membranes as follows: (a) in SEM studies on human erythrocytes it was observed that 0.5 mM PPA induced shape changes; (b) in IUM PPA induced a sharp decrease in the fluorescence anisotropy in the lipid bilayer acyl chains in a concentration range lower than 100 {mu}M; (c) X-ray diffraction studies showed that PPA in the 0

Delivery route determines the presence of immune complexes on umbilical cord erythrocytes.

PubMed

de Lima, Andrés; Franco, Luis C; Sarmiento, Andrés; González, John M

2017-11-01

Umbilical cord blood offers a unique opportunity to study the basal level of immunoglobulin complexes. This study aims to determine the presence of immune complexes and complement deposition on erythrocytes from umbilical cord blood from normal, full-term pregnancies. In vitro pre-formed IgA, IgG, and IgM complexes were used as positive control for flow cytometry detection, and for C3d deposition. Blood samples (34) of umbilical cord blood taken from vaginal and cesarean deliveries were tested for the presence of immunoglobulin complexes. Fourteen samples from vaginal deliveries and 20 samples from cesarean deliveries were assessed. IgG and IgM complexes were detected on erythrocytes, whereas no IgA complexes or complement deposition was observed. Interestingly, the percentage of IgG complexes was higher on erythrocytes from vaginal delivery samples compared to those from cesarean deliveries. No other associations between immune complexes and other maternal or newborn variables were found. IgG and IgM complexes seem to be normally present on umbilical cord erythrocytes. Erythrocytes from vaginal deliveries have a higher percentage of IgG complexes present compared to that from cesarean deliveries. Since no C3d activity was detected, these complexes are non-pathological and should be part of the newborn's initial innate immune response.

Expression of senescent antigen on erythrocytes infected with a knobby variant of the human malaria parasite Plasmodium falciparum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Winograd, E.; Greenan, J.R.T.; Sherman, I.W.

Erythrocytes infected with a knobby variant of Plasmodium falciparum selectively bind IgG autoantibodies in normal human serum. Quantification of membrane-bound IgG, by use of /sup 125/I-labeled protein A, revealed that erythrocytes infected with the knobby variant bound 30 times more protein A than did noninfected erythrocytes; infection with a knobless variant resulted in less than a 2-fold difference compared with noninfected erythrocytes. IgG binding to knobby erythrocytes appeared to be related to parasite development, since binding of /sup 125/I-labeled protein A to cells bearing young trophozoites (less than 20 hr after parasite invasion) was similar to binding to uninfected erythrocytes.more » By immunoelectron microscopy, the membrane-bound IgG on erythrocytes infected with the knobby variant was found to be preferentially associated with the protuberances (knobs) of the plasma membrane. The removal of aged or senescent erythrocytes from the peripheral circulation is reported to involve the binding of specific antibodies to an antigen (senescent antigen) related to the major erythrocyte membrane protein band 3. Since affinity-purified autoantibodies against band 3 specifically bound to the plasma membrane of erythrocytes infected with the knobby variant of P. falciparum, it is clear that the malaria parasite induces expression of senescent antigen.« less

Loss of the clock protein PER2 shortens the erythrocyte life span in mice.

PubMed

Sun, Qi; Zhao, Yue; Yang, Yunxia; Yang, Xiao; Li, Minghui; Xu, Xi; Wen, Dan; Wang, Junsong; Zhang, Jianfa

2017-07-28

Cell proliferation and release from the bone marrow have been demonstrated to be controlled by circadian rhythms in both humans and mice. However, it is unclear whether local circadian clocks in the bone marrow influence physiological functions and life span of erythrocytes. Here, we report that loss of the clock gene Per2 significantly decreased erythrocyte life span. Mice deficient in Per2 were more susceptible to acute stresses in the erythrocytes, becoming severely anemic upon phenylhydrazine, osmotic, and H 2 O 2 challenges. 1 H NMR-based metabolomics analysis revealed that the Per2 depletion causes significant changes in metabolic profiles of erythrocytes, including increased lactate and decreased ATP levels compared with wild-type mice. The lower ATP levels were associated with hyperfunction of Na + /K + -ATPase activity in Per2 -null erythrocytes, and inhibition of Na + /K + -ATPase activity by ouabain efficiently rescued ATP levels. Per2 -null mice displayed increased levels of Na + /K + -ATPase α1 (ATP1A1) in the erythrocyte membrane, and transfection of Per2 cDNA into the erythroleukemic cell line TF-1 inhibited Atp1a1 expression. Furthermore, we observed that PER2 regulates Atp1a1 transcription through interacting with trans-acting transcription factor 1 (SP1). Our findings reveal that Per2 function in the bone marrow is required for the regulation of life span in circulating erythrocytes. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Short preheating at 41°C leads to a red blood cells count comparable to that in RET channel of Sysmex analysers in samples showing cold agglutination.

PubMed

La Gioia, Antonio; Fumi, Maurizio; Fiorini, Fabiana; Pezzati, Paola; Balboni, Fiamma; Bombara, Maria; Marini, Alessandra; Pancione, Ylenia; Solarino, Leonardo; Marchese, Elisa; Sale, Silvia; Rocco, Vincenzo; Fiorini, Marcello

2018-03-13

The presence of cold agglutinin in blood samples can cause a spontaneous agglutination of red blood cells (RBCs) when low temperature occurs. This phenomenon causes a spurious lowering of RBC count on the automated haematological analysers that are detected by incongruous values (≥370 g/L) of the mean cellular haemoglobi concentration (MCHC). A preheating at 37°C can remove the RBC agglutination generally resulting in a reliable count. It has been reported that the same result can be reached by using the optical reticulocyte (RET) channel of Sysmex analysers where the RBC count is not influenced by the presence of cold agglutinin. This study aims to evaluate these data in a larger population, with regard to environmental conditions on Sysmex analysers. We have also evaluated the influence of different thermal pretreatments on the RBC count. This study was performed on 96 remnants of peripheral blood samples (48 with MCHC in normal range and 48 with MCHC > 370 g/L) which have been analysed in different preanalytical conditions on the Sysmex analysers. A preheating of samples at 41°C for 1 min leads to a reversibility of the cold agglutination comparable to the one observed in the RET channel and yields better results compared with 37°C for 2 hours. None of described procedures assure the complete cold agglutination reversibility in every case. Consequently, since the haematological analysers not yet provide reliable parameters to confirm the complete resolution of agglutination, further verification of RBC count accuracy needs to be performed. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Fatty acids of erythrocyte membrane in acute pancreatitis patients.

PubMed

Kuliaviene, Irma; Gulbinas, Antanas; Cremers, Johannes; Pundzius, Juozas; Kupcinskas, Limas; Dambrauskas, Zilvinas; Jansen, Eugene

2013-09-14

To evaluate changes in the fatty acid composition of erythrocyte membrane phospholipids during severe and mild acute pancreatitis (AP) of alcoholic and nonalcoholic etiology. All consecutive patients with a diagnosis of AP and onset of the disease within the last 72 h admitted to the Hospital of Lithuanian University of Health Sciences between June and December 2007 were included. According to the Acute Physiology and Chronic Health Evaluation (APACHE II) scale, the patients were subdivided into the mild (APACHE II score < 7, n = 22) and severe (APACHE II score ≥ 7, n = 17) AP groups. Healthy individuals (n = 26) were enrolled as controls. Blood samples were collected from patients on admission to the hospital. Fatty acids (FAs) were extracted from erythrocyte phospholipids and expressed as percentages of the total FAs present in the chromatogram. The concentrations of superoxide dismutase and glutathione peroxidase were measured in erythrocytes. We found an increase in the percentages of saturated and monounsaturated FAs, a decrease in the percentages of total polyunsaturated FAs (PUFAs) and n-3 PUFAs in erythrocyte membrane phospholipids of AP patients compared with healthy controls. Palmitic (C16:0), palmitoleic (C16:1n7cis), arachidonic (C20:4n6), docosahexaenoic (DHA, C22:6n3), and docosapentaenoic (DPA, C22:5n3) acids were the major contributing factors. A decrease in the peroxidation and unsaturation indexes in AP patients as well as the severe and mild AP groups as compared with controls was observed. The concentrations of antioxidant enzymes in the mild AP group were lower than in the control group. In severe AP of nonalcoholic etiology, the percentages of arachidic (C20:0) and arachidonic (C20:4n6) acids were decreased as compared with the control group. The patients with mild AP of nonalcoholic etiology had the increased percentages of total saturated FAs and gama linoleic acid (C18:3n6) and the decreased percentages of elaidic (C18:1n9t

Fatty acids of erythrocyte membrane in acute pancreatitis patients

PubMed Central

Kuliaviene, Irma; Gulbinas, Antanas; Cremers, Johannes; Pundzius, Juozas; Kupcinskas, Limas; Dambrauskas, Zilvinas; Jansen, Eugene

2013-01-01

AIM: To evaluate changes in the fatty acid composition of erythrocyte membrane phospholipids during severe and mild acute pancreatitis (AP) of alcoholic and nonalcoholic etiology. METHODS: All consecutive patients with a diagnosis of AP and onset of the disease within the last 72 h admitted to the Hospital of Lithuanian University of Health Sciences between June and December 2007 were included. According to the Acute Physiology and Chronic Health Evaluation (APACHE II) scale, the patients were subdivided into the mild (APACHE II score < 7, n = 22) and severe (APACHE II score ≥ 7, n = 17) AP groups. Healthy individuals (n = 26) were enrolled as controls. Blood samples were collected from patients on admission to the hospital. Fatty acids (FAs) were extracted from erythrocyte phospholipids and expressed as percentages of the total FAs present in the chromatogram. The concentrations of superoxide dismutase and glutathione peroxidase were measured in erythrocytes. RESULTS: We found an increase in the percentages of saturated and monounsaturated FAs, a decrease in the percentages of total polyunsaturated FAs (PUFAs) and n-3 PUFAs in erythrocyte membrane phospholipids of AP patients compared with healthy controls. Palmitic (C16:0), palmitoleic (C16:1n7cis), arachidonic (C20:4n6), docosahexaenoic (DHA, C22:6n3), and docosapentaenoic (DPA, C22:5n3) acids were the major contributing factors. A decrease in the peroxidation and unsaturation indexes in AP patients as well as the severe and mild AP groups as compared with controls was observed. The concentrations of antioxidant enzymes in the mild AP group were lower than in the control group. In severe AP of nonalcoholic etiology, the percentages of arachidic (C20:0) and arachidonic (C20:4n6) acids were decreased as compared with the control group. The patients with mild AP of nonalcoholic etiology had the increased percentages of total saturated FAs and gama linoleic acid (C18:3n6) and the decreased percentages of elaidic

Human Handling Promotes Compliant Behavior in Adult Laboratory Rabbits

PubMed Central

Swennes, Alton G; Alworth, Leanne C; Harvey, Stephen B; Jones, Carolyn A; King, Christopher S; Crowell-Davis, Sharon L

2011-01-01

Routine laboratory procedures can be stressful for laboratory animals. We wanted to determine whether human handling of adult rabbits could induce a degree of habituation, reducing stress and facilitating research-related manipulation. To this end, adult New Zealand white rabbits were handled either frequently or minimally. After being handled over 3 wk, these rabbits were evaluated by novel personnel and compared with minimally handled controls. Evaluators subjectively scored the rabbits for their relative compliance or resistance to being scruffed and removed from their cages, being transported to a treatment room, and their behavior at all stages of the exercise. Upon evaluation, handled rabbits scored significantly more compliant than nontreated controls. During evaluation, behaviors that the rabbits displayed when they were approached in their cages and while being handled outside their cages were recorded and compared between study groups. Handled rabbits displayed behavior consistent with a reduction in human-directed fear. This study illustrates the potential for handling to improve compliance in laboratory procedures and reduce fear-related behavior in laboratory rabbits. Such handling could be used to improve rabbit welfare through the reduction of stress and exposure to novel stimuli. PMID:21333162

Recognition of Human Erythrocyte Receptors by the Tryptophan-Rich Antigens of Monkey Malaria Parasite Plasmodium knowlesi.

PubMed

Tyagi, Kriti; Gupta, Deepali; Saini, Ekta; Choudhary, Shilpa; Jamwal, Abhishek; Alam, Mohd Shoeb; Zeeshan, Mohammad; Tyagi, Rupesh K; Sharma, Yagya D

2015-01-01

The monkey malaria parasite Plasmodium knowlesi also infect humans. There is a lack of information on the molecular mechanisms that take place between this simian parasite and its heterologous human host erythrocytes leading to this zoonotic disease. Therefore, we investigated here the binding ability of P. knowlesi tryptophan-rich antigens (PkTRAgs) to the human erythrocytes and sharing of the erythrocyte receptors between them as well as with other commonly occurring human malaria parasites. Six PkTRAgs were cloned and expressed in E.coli as well as in mammalian CHO-K1 cell to determine their human erythrocyte binding activity by cell-ELISA, and in-vitro rosetting assay, respectively. Three of six PkTRAgs (PkTRAg38.3, PkTRAg40.1, and PkTRAg67.1) showed binding to human erythrocytes. Two of them (PkTRAg40.1 and PkTRAg38.3) showed cross-competition with each other as well as with the previously described P.vivax tryptophan-rich antigens (PvTRAgs) for human erythrocyte receptors. However, the third protein (PkTRAg67.1) utilized the additional but different human erythrocyte receptor(s) as it did not cross-compete for erythrocyte binding with either of these two PkTRAgs as well as with any of the PvTRAgs. These three PkTRAgs also inhibited the P.falciparum parasite growth in in-vitro culture, further indicating the sharing of human erythrocyte receptors by these parasite species and the biological significance of this receptor-ligand interaction between heterologous host and simian parasite. Recognition and sharing of human erythrocyte receptor(s) by PkTRAgs with human parasite ligands could be part of the strategy adopted by the monkey malaria parasite to establish inside the heterologous human host.

Recognition of Human Erythrocyte Receptors by the Tryptophan-Rich Antigens of Monkey Malaria Parasite Plasmodium knowlesi

PubMed Central

Tyagi, Kriti; Gupta, Deepali; Saini, Ekta; Choudhary, Shilpa; Jamwal, Abhishek; Alam, Mohd. Shoeb; Zeeshan, Mohammad; Tyagi, Rupesh K.; Sharma, Yagya D.

2015-01-01

Background The monkey malaria parasite Plasmodium knowlesi also infect humans. There is a lack of information on the molecular mechanisms that take place between this simian parasite and its heterologous human host erythrocytes leading to this zoonotic disease. Therefore, we investigated here the binding ability of P. knowlesi tryptophan-rich antigens (PkTRAgs) to the human erythrocytes and sharing of the erythrocyte receptors between them as well as with other commonly occurring human malaria parasites. Methods Six PkTRAgs were cloned and expressed in E.coli as well as in mammalian CHO-K1 cell to determine their human erythrocyte binding activity by cell-ELISA, and in-vitro rosetting assay, respectively. Results Three of six PkTRAgs (PkTRAg38.3, PkTRAg40.1, and PkTRAg67.1) showed binding to human erythrocytes. Two of them (PkTRAg40.1 and PkTRAg38.3) showed cross-competition with each other as well as with the previously described P.vivax tryptophan-rich antigens (PvTRAgs) for human erythrocyte receptors. However, the third protein (PkTRAg67.1) utilized the additional but different human erythrocyte receptor(s) as it did not cross-compete for erythrocyte binding with either of these two PkTRAgs as well as with any of the PvTRAgs. These three PkTRAgs also inhibited the P.falciparum parasite growth in in-vitro culture, further indicating the sharing of human erythrocyte receptors by these parasite species and the biological significance of this receptor-ligand interaction between heterologous host and simian parasite. Conclusions Recognition and sharing of human erythrocyte receptor(s) by PkTRAgs with human parasite ligands could be part of the strategy adopted by the monkey malaria parasite to establish inside the heterologous human host. PMID:26393350

Effect of complete protein 4.1R deficiency on ion transportproperties of murine erythrocytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rivera, Alicia; De Franceschi, Lucia; Peters, Luanne L.

2006-06-02

Moderate hemolytic anemia, abnormal erythrocyte morphology(spherocytosis), and decreased membrane stability are observed in micewith complete deficiency of all erythroid protein 4.1 protein isoforms(4.1-/-; Shi TS et al., J. Clin. Invest. 103:331,1999). We have examinedthe effects of erythroid protein 4.1 (4.1R) deficiency on erythrocytecation transport and volume regulation. 4.1-/- mice exhibited erythrocytedehydration that was associated with reduced cellular K and increased Nacontent. Increased Na permeability was observed in these mice, mostlymediated by Na/H exchange with normal Na-K pump and Na-K-2Cl cotransportactivities. The Na/H exchange of 4.1-/- erythrocytes was markedlyactivated by exposure to hypertonic conditions (18.2+- 3.2 in 4.1 -/- vs.9.8 +-more » 1.3 mmol/1013 cell x h in control mice), with an abnormaldependence on osmolarity, (K0.5=417 +- 42 in 4.1 -/- vs. 460 +- 35 mOsmin control mice) suggestive of an up-regulated functional state. Whilethe affinity for internal protons was not altered (K0.5= 489.7 +- 0.7 vs.537.0+- 0.56 nM in control mice), the Vmax of the H-induced Na/H exchangeactivity was markedly elevated in 4.1-/- erythrocytes (Vmax 91.47Moderatehemolytic anemia, abnormal erythrocyte morphology (spherocytosis), anddecreased membrane stability are observed in mice with completedeficiency of all erythroid protein 4.1 protein isoforms (4.1-/-; Shi TSet al., J. Clin. Invest. 103:331,1999). We have examined the effects oferythroid protein 4.1 (4.1R) deficiency on erythrocyte cation transportand volume regulation. 4.1-/- mice exhibited erythrocyte dehydration thatwas associated with reduced cellular K and increased Na content.Increased Na permeability was observed in these mice, mostly mediated byNa/H exchange with normal Na-K pump and Na-K-2Cl cotransport activities.The Na/H exchange of 4.1-/- erythrocytes was markedly activated byexposure to hypertonic conditions (18.2 +- 3.2 in 4.1 -/- vs. 9.8 +- 1.3mmol/1013 cell x h in control mice

Interaction of Plasmodium falciparum knob-associated histidine-rich protein (KAHRP) with erythrocyte ankyrin R is required for its attachment to the erythrocyte membrane.

PubMed

Weng, Haibo; Guo, Xinhua; Papoin, Julien; Wang, Jie; Coppel, Ross; Mohandas, Narla; An, Xiuli

2014-01-01

The malaria parasite Plasmodium falciparum exports a large number of proteins into the erythrocyte cytoplasm during the asexual intraerythrocytic stage of its life cycle. A subset of these proteins interacts with erythrocyte membrane skeletal proteins and grossly alters the structure and function of the membrane. Several of the exported proteins, such as PfEMP1, PfEMP3, RESA and KAHRP, interact with the preponderant erythrocyte skeleton protein, spectrin. Here we have searched for possible interaction of these four malaria proteins with another major erythrocyte skeleton protein, ankyrin R. We have shown that KAHRP, but none of the other three, binds to ankyrin R. We have mapped the binding site for ankyrin R to a 79-residue segment of the KAHRP sequence, and the reciprocal binding site for KAHRP in ankyrin R to a subdomain (D3) of the 89kDa ankyrin R membrane-binding domain. Interaction of intact ankyrin R with KAHRP was inhibited by the free D3 subdomain. When, moreover, red cells loaded with the soluble D3 subdomain were infected with P. falciparum, KAHRP secreted by the intraerythrocytic parasite no longer migrated to the host cell membrane, but remained diffusely distributed throughout the cytosol. Our findings suggest a potentially important role for interaction of KAHRP with red cell membrane skeleton in promoting the adhesion of malaria-infected red cells to endothelial surfaces, a central element in the pathophysiology of malaria. © 2013.

Recruitment of human aquaporin 3 to internal membranes in the Plasmodium falciparum infected erythrocyte.

PubMed

Bietz, Sven; Montilla, Irine; Külzer, Simone; Przyborski, Jude M; Lingelbach, Klaus

2009-09-01

The molecular mechanisms underlying the formation of the parasitophorous vacuolar membrane in Plasmodium falciparum infected erythrocytes are incompletely understood, and the protein composition of this membrane is still enigmatic. Although the differentiated mammalian erythrocyte lacks the machinery required for endocytosis, some reports have described a localisation of host cell membrane proteins at the parasitophorous vacuolar membrane. Aquaporin 3 is an abundant plasma membrane protein of various cells, including mammalian erythrocytes where it is found in distinct oligomeric states. Here we show that human aquaporin 3 is internalized into infected erythrocytes, presumably during or soon after invasion. It is integrated into the PVM where it is organized in novel oligomeric states which are not found in non-infected cells.

Stimulation of Suicidal Erythrocyte Death by Tafenoquine.

PubMed

Al Mamun Bhuyan, Abdulla; Bissinger, Rosi; Stockinger, Katja; Lang, Florian

2016-01-01

The 8-aminoquinoline tafenoquine has been shown to be effective against Plasmodia, Leishmania and Trypanosoma. The substance is at least in part effective by triggering apoptosis of the parasites. Similar to apoptosis, erythrocytes may enter suicidal death or eryptosis, which is characterized by cell shrinkage and cell membrane scrambling with phosphatidylserine translocation to the erythrocyte surface. Signaling involved in the regulation of eryptosis include increase of cytosolic Ca2+ activity ([Ca2+]i), oxidative stress, ceramide, zVAD sensitive caspases, SB203580 sensitive p38 kinase, staurosporine sensitive protein kinase C as well as D4476 sensitive casein kinase. The present study explored, whether tafenoquine induces eryptosis and aimed to possibly identify cellular mechanisms involved. Flow cytometry was employed to estimate phosphatidylserine exposure at the cell surface from annexin-V-binding, cell volume from forward scatter, [Ca2+]i from Fluo3-fluorescence, ROS formation from 2',7'-dichlorodihydrofluorescein diacetate (DCFDA) dependent fluorescence, and ceramide abundance utilizing specific antibodies. A 48 hours exposure of human erythrocytes to tafenoquine (500 ng/ml) significantly increased the percentage of annexin-V-binding cells, significantly decreased forward scatter, significantly increased Fluo3-fluorescence, and significantly increased DCFDA fluorescence. Tafenoquine did not significantly modify ceramide abundance. The effect of tafenoquine on annexin-V-binding was significantly blunted but not abolished by removal of extracellular Ca2+. The effect of tafenoquine on annexin-V-binding was not significantly blunted by zVAD (10 µM), SB203580 (2 µM) or staurosporine (1 µM). The effect of tafenoquine on annexin-V-binding was significantly blunted but not abolished by D4476 (10 µM). Tafenoquine triggers cell shrinkage and phospholipid scrambling of the erythrocyte cell membrane, an effect at least in part due to stimulation of Ca2+ entry

The influence of erythrocyte maturity on ion transport and membrane lipid composition in the rat.