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Sample records for blood cells implications

  1. Introduction to porcine red blood cells: implications for xenotransfusion.

    PubMed

    Zhu, A

    2000-04-01

    Advances in the field of xenotransplantation raise the intriguing possibility of using porcine red blood cells (pRBCs) as an alternative source for blood transfusion. The domestic pig is considered the most likely donor species for xenotransplantation. However, identification of xenoantigens on porcine erythrocytes and elucidation of their possible roles in antibody-mediated RBC destruction are necessary for developing clinical strategies to circumvent immunological incompatibility between humans and pigs. Although the alphaGal epitope (Galalpha1,3Galbeta1,4GIcNAc-R) is the major xenoantigen on porcine erythrocytes and is responsible for the binding of the majority of human natural antibodies, other non-alphaGal xenoantigens have been identified. The importance of these non-alphaGal xenoantigens in binding human natural antibodies and subsequently triggering immunological responses cannot be underestimated. Our data suggest that non-alphaGal xenoantigen(s) identified on the porcine erythrocyte membrane are not only recognized by xenoreactive human natural antibodies but are also involved in complement-mediated hemolysis.

  2. A role for activated endothelial cells in red blood cell clearance: implications for vasopathology.

    PubMed

    Fens, Marcel H A M; van Wijk, Richard; Andringa, Grietje; van Rooijen, Karlijn L; Dijstelbloem, Hilde M; Rasmussen, Jan T; de Vooght, Karen M K; Schiffelers, Raymond M; Gaillard, Carlo A J M; van Solinge, Wouter W

    2012-04-01

    Phosphatidylserine exposure by red blood cells is acknowledged as a signal that initiates phagocytic removal of the cells from the circulation. Several disorders and conditions are known to induce phosphatidylserine exposure. Removal of phosphatidylserine-exposing red blood cells generally occurs by macrophages in the spleen and liver. Previously, however, we have shown that endothelial cells are also capable of erythrophagocytosis. Key players in the erythrophagocytosis by endothelial cells appeared to be lactadherin and α(v)-integrin. Phagocytosis via the phosphatidylserine-lactadherin-α(v)-integrin pathway is the acknowledged route for removal of apoptotic innate cells by phagocytes. Endothelial cell phagocytosis of red blood cells was further explored using a more (patho)physiological approach. Red blood cells were exposed to oxidative stress, induced by tert-butyl hydroperoxide. After opsonization with lactadherin, red blood cells were incubated with endothelial cells to study erythrophagocytosis and examine cytotoxicity. Red blood cells exposed to oxidative stress show alterations such as phosphatidylserine exposure and loss of deformability. When incubated with endothelial cells, marked erythrophagocytosis occurred in the presence of lactadherin under both static and flow conditions. As a consequence, intracellular organization was disturbed and endothelial cells were seen to change shape ('rounding up'). Increased expression of apoptotic markers indicated that marked erythrophagocytosis has cytotoxic effects. Activated endothelial cells show significant phagocytosis of phosphatidylserine-exposing and rigid red blood cells under both static and flow conditions. This results in a certain degree of cytotoxicity. We postulate that activated endothelial cells play a role in red blood cell clearance in vivo. Significant erythrophagocytosis can induce endothelial cell loss, which may contribute to vasopathological effects as seen, for instance, in sickle cell

  3. A role for activated endothelial cells in red blood cell clearance: implications for vasopathology

    PubMed Central

    Fens, Marcel H.A.M.; van Wijk, Richard; Andringa, Grietje; van Rooijen, Karlijn L.; Dijstelbloem, Hilde M.; Rasmussen, Jan T.; de Vooght, Karen M.K.; Schiffelers, Raymond M.; Gaillard, Carlo A.J.M.; van Solinge, Wouter W.

    2012-01-01

    Background Phosphatidylserine exposure by red blood cells is acknowledged as a signal that initiates phagocytic removal of the cells from the circulation. Several disorders and conditions are known to induce phosphatidylserine exposure. Removal of phosphatidylserine-exposing red blood cells generally occurs by macrophages in the spleen and liver. Previously, however, we have shown that endothelial cells are also capable of erythrophagocytosis. Key players in the erythrophagocytosis by endothelial cells appeared to be lactadherin and αv-integrin. Phagocytosis via the phosphatidylserine-lactadherin-αv-integrin pathway is the acknowledged route for removal of apoptotic innate cells by phagocytes. Design and Methods Endothelial cell phagocytosis of red blood cells was further explored using a more (patho)physiological approach. Red blood cells were exposed to oxidative stress, induced by tert-butyl hydroperoxide. After opsonization with lactadherin, red blood cells were incubated with endothelial cells to study erythrophagocytosis and examine cytotoxicity. Results Red blood cells exposed to oxidative stress show alterations such as phosphatidylserine exposure and loss of deformability. When incubated with endothelial cells, marked erythrophagocytosis occurred in the presence of lactadherin under both static and flow conditions. As a consequence, intracellular organization was disturbed and endothelial cells were seen to change shape (‘rounding up’). Increased expression of apoptotic markers indicated that marked erythrophagocytosis has cytotoxic effects. Conclusions Activated endothelial cells show significant phagocytosis of phosphatidylserine-exposing and rigid red blood cells under both static and flow conditions. This results in a certain degree of cytotoxicity. We postulate that activated endothelial cells play a role in red blood cell clearance in vivo. Significant erythrophagocytosis can induce endothelial cell loss, which may contribute to

  4. Identification of fetal mesenchymal stem cells in maternal blood: implications for non-invasive prenatal diagnosis.

    PubMed

    O'Donoghue, K; Choolani, M; Chan, J; de la Fuente, J; Kumar, S; Campagnoli, C; Bennett, P R; Roberts, I A G; Fisk, N M

    2003-08-01

    Strategies for genetic prenatal diagnosis on fetal cells in the maternal circulation have been limited by lack of a cell type present only in fetal blood. However, the recent identification of mesenchymal stem cells (MSC) in first trimester fetal blood offers the prospect of targeting MSC for non-invasive prenatal diagnosis. We developed protocols for fetal MSC enrichment from maternal blood and determined sensitivity and specificity in mixing experiments of male fetal MSC added to female blood, in dilutions from 1 in 10(5) to 10(8). We then used the optimal protocol to isolate fetal MSC from maternal blood in the first trimester, using blood taken after surgical termination of pregnancy as a model of increased feto-maternal haemorrhage. In model mixtures, we could amplify one male fetal MSC in 2.5 x 10(7) adult female nucleated cells, yielding a 100% pure population of fetal cells, but not one fetal MSC in 10(8) nucleated cells. Fetal MSC were identified in one of 20 post-termination maternal blood samples and confirmed as fetal MSC by XY fluorescence in-situ hybridization (FISH), immunophenotyping and osteogenic and adipogenic differentiation. We report the isolation of fetal MSC from maternal blood; however, their rarity in post-termination blood suggests they are unlikely to have a role in non-invasive prenatal diagnosis. Failure to locate these cells routinely may be attributed to their low frequency in maternal blood, to sensitivity limitations of enrichment technology, and/or to their engraftment in maternal tissues soon after transplacental passage. We speculate that gender microchimerism in post-reproductive maternal tissues might result from feto-maternal trafficking of MSC in early pregnancy.

  5. Mast Cell - Glia Dialogue in Chronic Pain and Neuropathic Pain: Blood-Brain Barrier Implications.

    PubMed

    Skaper, Stephen D

    2016-01-01

    Mast cells and microglia, working singly and in partnership, produce proinflammatory agents which play key roles in a wide array of nervous system disorders. Such neuroinflammatory settings may compromise integrity of both the blood-nerve barrier and blood-brain barrier (BBB) and blood-spinal cord barrier. While both belong to the innate immune system mast cells are far more ubiquitous, are resident in peripheral nerves and the central nervous system, and can influence blood-nerve barrier characteristics. Mast cells, being near the perivasculature especially within the dura, on the brain side of the BBB, are strategically located to play havoc with the BBB. Mast cells and glia are endowed with homeostatic mechanisms/molecules which come into play following tissue damage. These include the N-acylethanolamine family, especially N-palmitoylethanolamine, which is posited to be a key player in maintaining cellular homeostasis against external stressors provoking, for example, inflammation. This review is intended as an overview covering the pathobiology of neuroinflammation in the context of mast cells and microglia, their role in BBB integrity, and therapeutic perspectives in targeting these cells to preserve BBB function.

  6. Methods of ex vivo expansion of human cord blood cells: challenges, successes and clinical implications.

    PubMed

    Baron, Frédéric; Ruggeri, Annalisa; Nagler, Arnon

    2016-03-01

    More than 40,000 unrelated cord blood transplantations (UCBT) have been performed worldwide as treatment for patients with malignant or non-malignant life threatening hematologic disorders. However, low absolute numbers of hematopoietic stem and progenitor cells (HSPCs) within a single cord blood unit has remained a limiting factor for this transplantation modality, particularly in adult recipients. Further, because UCB contains low numbers of mostly naïve T cells, immune recovery after UCBT is slow, predisposing patients to severe infections. Other causes of UCBT failure has included graft-versus-host disease (GVHD) and relapse of the underlying disease. In this article, we first review the current landscape of cord blood engineering aimed at improving engraftment. This includes approaches of UCB-HSPCs expansion and methods aimed at improving UCB-HSCPs homing. We then discuss recent approaches of cord blood engineering developed to prevent infection [generation of multivirus-specific cytotoxic T cells (VSTs) from UCB], relapse [transduction of UCB-T cells with tumor-specific chimeric receptor antigens (CARs)] and GVHD (expansion of regulatory T cells from UCB). Although many of these techniques of UCB engineering remain currently technically challenging and expensive, they are likely to revolutionize the field of UCBT in the next decades.

  7. Autoantibody formation in the alloimmunized red blood cell recipient: clinical and laboratory implications.

    PubMed

    Zumberg, M S; Procter, J L; Lottenberg, R; Kitchens, C S; Klein, H G

    2001-01-22

    Alloimmunization to erythrocyte antigens is a well-characterized complication in heavily transfused patients. Less well recognized, however, is the frequency of autoantibody formation in these previously alloimmunized patients. The autoantibodies are heterogeneous and of variable clinical significance. We describe the clinical history, laboratory evaluation, diagnosis, and treatment in 4 patients who developed autoantibodies in temporal association with alloantibody formation. In one case, the autoantibody found on routine screening had no clinical significance. In another case, the autoantibody made accurate blood typing and subsequent transfusion exceedingly difficult. Two patients experienced hemolysis as a consequence of the autoantibody. The management of both patients included supportive measures, while one patient required glucocorticosteroids and red blood cell transfusion. We review the published literature concerning autoimmunization in the transfused alloimmunized host. The spectrum of clinical consequences is important for the general practitioner to recognize, as these complications may occur during routine blood transfusions.

  8. PSP activates monocytes in resting human peripheral blood mononuclear cells: immunomodulatory implications for cancer treatment.

    PubMed

    Sekhon, Bhagwant Kaur; Sze, Daniel Man-Yuen; Chan, Wing Keung; Fan, Kei; Li, George Qian; Moore, Douglas Edwin; Roubin, Rebecca Heidi

    2013-06-15

    Polysaccharopeptide (PSP), from Coriolus versicolor, has been used as an adjuvant to chemotherapy, and has demonstrated anti-tumor and immunomodulating effects. However its mechanism remains unknown. To elucidate how PSP affects immune populations, we compared PSP treatments both with and without prior incubation in phytohaemagglutinin (PHA) - a process commonly used in immune population experimentation. We first standardised a capillary electrophoresis fingerprinting technique for PSP identification and characterisation. We then established the proliferative capability of PSP on various immune populations in peripheral blood mononuclear cells, using flow cytometry, without prior PHA treatment. It was found that PSP significantly increased the number of monocytes (CD14(+)/CD16(-)) compared to controls without PHA. This increase in monocytes was confirmed using another antibody panel of CD14 and MHCII. In contrast, proliferations of T-cells, NK, and B-cells were not significantly changed by PSP. Thus, stimulating monocyte/macrophage function with PSP could be an effective therapeutic intervention in targeting tumors.

  9. Dehydration and delayed proton equilibria of red blood cells suspended in isosmotic phosphate buffers. Implications for studies of sickled cells.

    PubMed

    Bookchin, R M; Lew, D J; Balazs, T; Ueda, Y; Lew, V L

    1984-12-01

    PO4 buffers isosmotic with plasma or phosphate-buffered saline solution with a substantial proportion of PO4 are often used to wash and suspend red blood cells in studies of respiratory or sickling behavior. Measurements of sequential changes in mean cell hemoglobin concentration, pH, and ion content of red blood cells suspended in 295 mOsm Na-phosphate, pH 7.4, at 23 degrees or 37 degrees C, showed (1) rapid, persistent cell dehydration (mean cell hemoglobin concentration greater than 40 gm/dl) caused initially by Cl- efflux and later by replacement of monovalent Cl- by divalent HPO=4; and (2) temporary reversal of membrane pH gradients with normalization time (30 to 120 minutes) dependent on factors controlling the rate of phosphate-chloride exchange. Sequential equilibration of red blood cells in isosmotic citrate (impermeable) followed by PO4 demonstrated the two stages of the observed shifts in PO4 alone, and red blood cells suspended in 0.15 mol/L 32PO4 at 37 degrees C showed PO4 influx consistent with pH equilibrium kinetics. Sickle trait red blood cells deoxygenated at 37 degrees C, pH 7.4, in plasma or 10 mmol/L HEPES-buffered saline solution showed only 6% to 20% sickling. In isosmotic PO4, mean cell hemoglobin concentration was 40 to 41 gm/dl with approximately 80% sickling. In phosphate-buffered saline solution containing 70 mmol/L PO4, red blood cells showed smaller, similar changes (mean cell hemoglobin concentration approximately 38 gm/dl) with a longer equilibration period and deoxygenated sickle trait cells showed 40% sickling. The altered properties of red blood cells suspended in PO4 or phosphate-buffered saline solution were neither intended nor appropriate for many studies using these media, particularly with hemoglobin S-containing red blood cells, and interpretations of reported results must be reassessed in light of these findings.

  10. Redox imbalance of red blood cells impacts T lymphocyte homeostasis: implication in carotid atherosclerosis.

    PubMed

    Profumo, Elisabetta; Buttari, Brigitta; Petrone, Linda; Straface, Elisabetta; Gambardella, Lucrezia; Pietraforte, Donatella; Genuini, Igino; Capoano, Raffaele; Salvati, Bruno; Malorni, Walter; Riganò, Rachele

    2011-12-01

    Oxidative stress and immune/inflammatory responses are key pathogenetic factors of atherosclerotic disease. In this contest, mechanisms that regulate survival and death of immune cells may be relevant. Previous studies have demonstrated that red blood cells (RBCs) are physiologically able to inhibit apoptosis and to promote proliferation of activated T lymphocytes from healthy subjects. The aim of the present study was to evaluate whether RBCs from patients with carotid atherosclerosis maintain their property to modulate T cell homeostasis. Peripheral blood lymphocytes (PBLs) obtained from healthy subjects were activated in vitro by phytohemagglutinin in the presence/absence of RBCs from patients with carotid atherosclerosis or of in vitro oxidised RBCs from healthy subjects. Levels of reactive oxygen species (ROS) and aging markers of RBCs as well as susceptibility to apoptosis of PBLs were evaluated by flow cytometry. PBL proliferation was evaluated by 3H-methyl-thymidine incorporation assay whereas secretion of cytokines, analysed in view of their key role in T cell function, was assessed by ELISA. Levels of ROS and phosphatidyl-serine externalisation, a sign of RBC aging, resulted significantly higher in RBCs from patients than in those from healthy subjects, whereas surface glycophorin A expression and reduced glutathione content did the opposite. Unlike RBCs obtained from healthy subjects, RBCs from patients and in vitro oxidised RBCs did not protect activated T lymphocytes from apoptosis. Hence, RBCs from patients with carotid atherosclerosis, probably due to their oxidative imbalance, impact T cell integrity and function. Our results suggest a new regulatory role for RBCs in atherosclerosis.

  11. White Blood Cell Count

    MedlinePlus

    ... limited. Home Visit Global Sites Search Help? White Blood Cell Count Share this page: Was this page helpful? ... Count; Leukocyte Count; White Count Formal name: White Blood Cell Count Related tests: Complete Blood Count , Blood Smear , ...

  12. Vertebrate blood cell volume increases with temperature: implications for aerobic activity

    PubMed Central

    Zenil-Ferguson, Rosana

    2014-01-01

    Aerobic activity levels increase with body temperature across vertebrates. Differences in these levels, from highly active to sedentary, are reflected in their ecology and behavior. Yet, the changes in the cardiovascular system that allow for greater oxygen supply at higher temperatures, and thus greater aerobic activity, remain unclear. Here we show that the total volume of red blood cells in the body increases exponentially with temperature across vertebrates, after controlling for effects of body size and taxonomy. These changes are accompanied by increases in relative heart mass, an indicator of aerobic activity. The results point to one way vertebrates may increase oxygen supply to meet the demands of greater activity at higher temperatures. PMID:24765580

  13. Red blood cell production

    MedlinePlus

    ... to one part of the body or another. Red blood cells are an important element of blood. Their job ... is carried to and eliminated by the lungs. Red blood cells are formed in the red bone marrow of ...

  14. White Blood Cell Disorders

    MedlinePlus

    ... Examination (Video) Blood Clots: Plugging the Breaks (News) Drone Sets New Record for Transporting Blood Samples (News) ... cells Am I Correct? More Videos News HealthDay Drone Sets New Record for Transporting Blood Samples TUESDAY, ...

  15. Methylmercury-Induced Dysfunction of Blood Vessel Cells: Implications in Cardiovascular Diseases

    DTIC Science & Technology

    2008-12-01

    coronary heart disease ( Yoshizawa et al. 2002). Increased levels of mercury in the blood have also been associated with elevated cholesterol levels in...and oxidative stress. Curr. Med. Chem. 12:1161–208. Yoshizawa , K., E. B. Rimm, J. S. Morris,V. L. Spate, C. CHsieh, D. Spiegelman, M. J. Stampfer

  16. Low usage rate of banked sibling cord blood units in hematopoietic stem cell transplantation for children with hematological malignancies: implications for directed cord blood banking policies.

    PubMed

    Goussetis, Evgenios; Peristeri, Ioulia; Kitra, Vasiliki; Papassavas, Andreas C; Theodosaki, Maria; Petrakou, Eftichia; Spiropoulos, Antonia; Paisiou, Anna; Soldatou, Alexandra; Stavropoulos-Giokas, Catherine; Graphakos, Stelios

    2011-02-15

    Directed sibling cord blood banking is indicated in women delivering healthy babies who already have a sibling with a disease that is potentially treatable with an allogeneic cord blood transplant. We evaluated the effectiveness of a national directed cord blood banking program in sibling HLA-identical stem cell transplantation for hematological malignancies and the factors influencing the usage rate of the stored cord blood units. Fifty families were enrolled from which, 48 cord blood units were successfully collected and 2 collections failed due to damaged cord/placenta at delivery. Among enrolled families 4 children needed transplantation; however, only one was successfully transplanted using the collected cord blood unit containing 2×10(7) nucleated cells/kg in conjunction with a small volume of bone marrow from the same HLA-identical donor. Two children received grafts from matched unrelated donors because their sibling cord blood was HLA-haploidentical, while the fourth one received bone marrow from his HLA-identical brother, since cord blood could not be collected due to damaged cord/placenta at delivery. With a median follow-up of 6 years (range, 2-12) for the 9 remaining HLA-matched cord blood units, none from the prospective recipients needed transplantation. The low utilization rate of sibling cord blood in the setting of hematopoietic stem cell transplantation for pediatric hematological malignant diseases necessitates the development of directed cord blood banking programs that limit long-term storage for banked cord blood units with low probability of usage such as non-HLA-identical or identical to patients who are in long-term complete remission.

  17. Immune Cells in Blood Recognize Tumors

    Cancer.gov

    NCI scientists have developed a novel strategy for identifying immune cells circulating in the blood that recognize specific proteins on tumor cells, a finding they believe may have potential implications for immune-based therapies.

  18. Quantitative peripheral blood perturbations of γδ T cells in human disease and their clinical implications.

    PubMed

    Bank, Ilan; Marcu-Malina, Victoria

    2014-12-01

    Human γδ T cells, which play innate and adaptive, protective as well as destructive, roles in the immune response, were discovered in 1986, but the clinical significance of alterations of the levels of these cells in the peripheral blood in human diseases has not been comprehensively reviewed. Here, we review patterns of easily measurable changes of this subset of T cells in peripheral blood from relevant publications in PubMed and their correlations with specific disease categories, specific diagnoses within disease categories, and prognostic outcomes. These collective data suggest that enumeration of γδ T cells and their subsets in the peripheral blood of patients could be a useful tool to evaluate diagnosis and prognosis in the clinical setting.

  19. Analysis of leucocyte antibodies, cytokines, lysophospholipids and cell microparticles in blood components implicated in post-transfusion reactions with dyspnoea.

    PubMed

    Maślanka, K; Uhrynowska, M; Łopacz, P; Wróbel, A; Smoleńska-Sym, G; Guz, K; Lachert, E; Ostas, A; Brojer, E

    2015-01-01

    Post-transfusion reactions with dyspnoea (PTR) are major causes of morbidity and death after blood transfusion. Transfusion-related acute lung injury (TRALI) and transfusion-associated circulatory overload (TACO) are most dangerous, while transfusion-associated dyspnoea (TAD) is a milder respiratory distress. We investigated blood components for immune and non-immune factors implicated in PTR. We analysed 464 blood components (RBCs, PLTs, L-PLTs, FFP) transfused to 271 patients with PTR. Blood components were evaluated for 1/antileucocyte antibodies, 2/cytokines: IL-1β, IL-6, IL-8, TNF-α, sCD40L, 3/lysophosphatidylcholines (LysoPCs), 4/microparticles (MPs) shed from plateletes (PMPs), erythrocytes (EMPs) and leucocytes (LMPs). Anti-HLA class I/II antibodies or granulocyte-reactive anti-HLA antibodies were detected in 18.2% of blood components (RBC and FFP) transfused to TRALI and in 0.5% of FFP transfused to TAD cases. Cytokines and LysoPCs concentrations in blood components transfused to PTR patients did not exceed those in blood components transfused to patients with no PTR. Only EMPs percentage in RBCs transfused to patients with TRALI was significantly higher (P < 0.05) than in RBCs transfused to patients with no PTR. Immune character of PTR was confirmed mainly in 1/5 TRALI cases. Among non-immune factors, only MPs released from stored RBCs are suggested as potential mediators of TRALI. Our results require further observations in a more numerous and better defined group of patients. © 2014 International Society of Blood Transfusion.

  20. Mitochondrial dysfunction and mitophagy activation in blood mononuclear cells of fibromyalgia patients: implications in the pathogenesis of the disease

    PubMed Central

    2010-01-01

    Introduction Fibromyalgia is a chronic pain syndrome with unknown etiology. Recent studies have shown some evidence demonstrating that oxidative stress may have a role in the pathophysiology of fibromyalgia. However, it is still not clear whether oxidative stress is the cause or the effect of the abnormalities documented in fibromyalgia. Furthermore, the role of mitochondria in the redox imbalance reported in fibromyalgia also is controversial. We undertook this study to investigate the role of mitochondrial dysfunction, oxidative stress, and mitophagy in fibromyalgia. Methods We studied 20 patients (2 male, 18 female patients) from the database of the Sevillian Fibromyalgia Association and 10 healthy controls. We evaluated mitochondrial function in blood mononuclear cells from fibromyalgia patients measuring, coenzyme Q10 levels with high-performance liquid chromatography (HPLC), and mitochondrial membrane potential with flow cytometry. Oxidative stress was determined by measuring mitochondrial superoxide production with MitoSOX™ and lipid peroxidation in blood mononuclear cells and plasma from fibromyalgia patients. Autophagy activation was evaluated by quantifying the fluorescence intensity of LysoTracker™ Red staining of blood mononuclear cells. Mitophagy was confirmed by measuring citrate synthase activity and electron microscopy examination of blood mononuclear cells. Results We found reduced levels of coenzyme Q10, decreased mitochondrial membrane potential, increased levels of mitochondrial superoxide in blood mononuclear cells, and increased levels of lipid peroxidation in both blood mononuclear cells and plasma from fibromyalgia patients. Mitochondrial dysfunction was also associated with increased expression of autophagic genes and the elimination of dysfunctional mitochondria with mitophagy. Conclusions These findings may support the role of oxidative stress and mitophagy in the pathophysiology of fibromyalgia. PMID:20109177

  1. Post-thaw viability of cryopreserved peripheral blood stem cells (PBSC) does not guarantee functional activity: important implications for quality assurance of stem cell transplant programmes.

    PubMed

    Morgenstern, Daniel A; Ahsan, Gulrukh; Brocklesby, Margaret; Ings, Stuart; Balsa, Carmen; Veys, Paul; Brock, Penelope; Anderson, John; Amrolia, Persis; Goulden, Nicholas; Cale, Catherine M; Watts, Michael J

    2016-09-01

    Standard quality assurance (QA) of cryopreserved peripheral blood stem cells (PBSC) uses post-thaw viable CD34(+) cell counts. In 2013, concerns arose at Great Ormond Street Hospital (GOSH) about 8 patients with delayed engraftment following myeloablative chemotherapy with cryopreserved cell rescue, despite adequate post-thaw viable cell counts in all cases. Root cause analysis was undertaken; investigations suggested the freeze process itself was a contributing factor to suboptimal engraftment. Experiments were undertaken in which a single PBSC product was divided into three and cryopreserved in parallel using a control-rate freezer (CRF) or passive freezing method (-80°C freezer) at GOSH, or the same passive freezing at another laboratory. Viable CD34(+) counts were equivalent and adequate in each. Granulocyte-monocyte colony-forming unit assays demonstrated colonies from the products cryopreserved using passive freezing (both laboratories), but no colonies from products cryopreserved using the CRF. The CRF was shown to be operating within manufacturer's specifications with freeze-profile within acceptable limits. This experience has important implications for quality assurance for all transplant programmes, particularly those using cryopreserved products. The failure of post-thaw viable CD34(+) counts, the most widely used routine QA test available, to ensure PBSC function is of great concern and should prompt reassessment of protocols and QA procedures. © 2016 John Wiley & Sons Ltd.

  2. High Red Blood Cell Count

    MedlinePlus

    Symptoms High red blood cell count By Mayo Clinic Staff A high red blood cell count is an increase in oxygen-carrying cells in your bloodstream. Red blood cells transport oxygen from your lungs to tissues throughout ...

  3. Microvascular invasion of testicular nonseminomatous germ cell tumors: implications of separate evaluation of lymphatic and blood vessels.

    PubMed

    Heinzelbecker, Julia; Gross-Weege, Matthias; Weiss, Christel; Hörner, Christian; Trunk, Marcus J; Erben, Philipp; Haecker, Axel; Bolenz, Christian

    2014-08-01

    We separately evaluated the lymphatic and blood vascular systems to assess the diagnostic accuracy of microvascular invasion and identify predictive markers for occult metastasis of testicular nonseminomatous germ cell tumors. Tissue samples of 86 patients treated for testicular nonseminomatous germ cell tumors (stage 1 in 48 and stage greater than 1 in 38) were stained using the lymphatic endothelial cell specific marker LYVE-1 and the blood vessel endothelial cell marker von Willebrand factor. We assessed lymph vessel density in LYVE-1 stained sections and blood vessel density in von Willebrand factor stained sections. Lymphovascular invasion in LYVE-1 stained sections and blood vascular invasion in von Willebrand factor stained sections were documented. Parameters were correlated with standard clinicopathological data. Blood vessel density in von Willebrand factor sections was significantly greater than lymphatic vessel density in LYVE-1 sections (p<0.001). Peritumor and nontumor lymphatic vessel density in LYVE-1 sections was associated with metastasis at diagnosis (OR 1.277/U, p=0.020 and OR 1.113/U, p=0.095). Lymphovascular invasion in LYVE-1 sections was significantly associated with metastasis (OR=4.517, p=0.002) but blood vascular invasion in von Willebrand factor sections was only slightly significant (OR 2.261, p=0.071). Only lymphovascular invasion in LYVE-1 stained sections was significantly associated with metastasis in a multiple logistic regression model. Microvascular invasion in hematoxylin and eosin stained sections was not associated with metastasis but microvascular invasion evaluated in LYVE-1 and von Willebrand factor stained sections was associated with metastasis (OR 3.506, p=0.016). Lymphovascular invasion in LYVE-1 stained sections was the most important predictive parameter for metastasis at diagnosis, suggesting greater relevance of the lymphatic system in metastatic dissemination of testicular nonseminomatous germ cell tumors. Vascular

  4. Occult Hepatitis B virus infection in previously screened, blood donors in Ile-Ife, Nigeria: implications for blood transfusion and stem cell transplantation.

    PubMed

    Olotu, Amadin A; Oyelese, Adesola O; Salawu, Lateef; Audu, Rosemary A; Okwuraiwe, Azuka P; Aboderin, Aaron O

    2016-05-05

    Hepatitis B virus (HBV) transmission through blood transfusion is reduced by screening for hepatitis B surface antigen (HBsAg). However this method cannot detect the presence of occult hepatitis B virus infection. This study sought to determine the prevalence of occult hepatitis B virus infection among blood donors in Ile-Ife, Nigeria. For the first time in Nigeria we employed an automated real-time PCR- method to investigate the prevalence of occult HBV in blood donors. Blood donors screened with HBsAg immunochromatographic rapid test kits at the blood transfusion units of two hospitals and found to be negative were recruited into the study. Questionnaires to elicit risk factors for HBV infection were administered and then 10 ml of blood was collected from each donor. Plasma samples obtained from these HBsAg negative blood donors were screened again for HBsAg using an enzyme-linked immunosorbent assay (ELISA) method, and those found negative were screened for the presence of total antibody to the HBV core antigen (anti-HBc) using ELISA method. Those positive to anti-HBc were then tested for HBV DNA, using an automated real-time PCR method. Five hundred and seven blood donors found HBsAg negative by immunochromatographic rapid test kits at both blood transfusion units, were tested for HBsAg using ELISA and 5 (1 %) were HBsAg positive. The 502 found negative were tested for anti-HBc and 354 (70.5 %) were found positive implying previous exposure to HBV and 19 (5.4 %) of the 354 anti-HBc positive had HBV DNA signifying occult HBV infection. No risk factors were found to be associated with the presence of HBV DNA among those who tested positive. Occult HBV infection exists in blood donors in Ile-Ife, Nigeria and the use of HBsAg alone for screening prospective donors will not eliminate the risk of HBV transmission in blood transfusion or stem cell transplantation.

  5. Blood Pressure Regulation VIII: Resistance Vessel Tone and Implications for a Pro-Atherogenic Conduit Artery Endothelial Cell Phenotype

    PubMed Central

    Padilla, Jaume; Jenkins, Nathan T.; Laughlin, M. Harold; Fadel, Paul J.

    2013-01-01

    Dysfunction of the endothelium is proposed as the primary initiator of atherosclerotic peripheral artery disease, which occurs mainly in medium to large-sized conduit arteries of the lower extremities (e.g., iliac, femoral, popliteal arteries). In this review article, we propose the novel concept that conduit artery endothelial cell phenotype is determined, in part, by microvascular tone in skeletal muscle resistance arteries through both changes in arterial blood pressure as well as upstream conduit artery shear stress patterns. First, we summarize the literature supporting the involvement of sympathetic nerve activity (SNA) and nitric oxide (NO) in the modulation of microvascular tone and arterial blood pressure. We then focus on the role of elevated blood pressure and shear stress profiles in modulating conduit artery endothelial cell phenotype. Last, we discuss findings from classic and emerging studies indicating that increased vascular resistance, as it occurs in the context of increased SNA and/or reduced NO bioavailability, is associated with greater oscillatory shear stress (e.g., increased retrograde shear) in upstream conduit arteries. The ideas put forth in this review set the stage for a new paradigm concerning the mechanistic link between increased microvascular tone and development of conduit artery endothelial dysfunction and thus increased risk for peripheral artery disease. Indeed, a vast amount of evidence supports the notion that excessive blood pressure and oscillatory shear stress are potent pro-atherogenic signals to the endothelium. PMID:23860841

  6. Cord blood natural killer cells expressing a dominant negative TGF-β receptor: Implications for adoptive immunotherapy for glioblastoma.

    PubMed

    Yvon, Eric S; Burga, Rachel; Powell, Allison; Cruz, Conrad R; Fernandes, Rohan; Barese, Cecilia; Nguyen, Tuongvan; Abdel-Baki, Mohamed S; Bollard, Catherine M

    2017-03-01

    Cord blood (CB) natural killer (NK) cells are promising effector cells for tumor immunotherapy but are currently limited by immune-suppressive cytokines in the tumor microenvironment, such as transforming growth factor (TGF-β). We observed that TGF-β inhibits expression of activating receptors such as NKG2D and DNAM1 and decreases killing activity against glioblastoma tumor cells through inhibition of perforin secretion. To overcome the detrimental effects of TGF-β, we engrafted a dominant negative TGF-β receptor II (DNRII) on CB-derived NK cells by retroviral transduction and evaluated their ability to kill glioblastoma cells in the presence of TGF-β. After manufacture using Good Manufacturing Practice-compliant methodologies and transduction with DNRII, CB-derived DNRII-transduced NK cells expanded to clinically relevant numbers and retained both their killing ability and their secretion of interferon-γ upon activation. More important, these cells maintained both perforin expression and NKG2D/DNMA1 expression in the presence of TGF-β allowing for recognition and killing of glioblastoma tumor cells. Hence, NK cells expressing a DNRII should have a functional advantage over unmodified NK cells in the presence of TGF-β-secreting tumors and may be an important therapeutic approach for patients with cancer. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  7. Seroprevalence of Human T-Cell Lymphotropic Virus-1/2 in Blood Donors in Northern Pakistan: Implications for Blood Donor Screening.

    PubMed

    Niazi, Saifullah Khan; Bhatti, Farhat Abbas; Salamat, Nuzhat

    2015-12-01

    To determine the seroprevalence of Human T-cell Lymphotropic Virus-1/2 (HTLV-1/2) in blood donors in Northern Pakistan. Descriptive study. Armed Forces Institute of Transfusion, Rawalpindi, from July to August 2013. A total of 2100 blood donors were screened for anti-HTLV-1/2 antibodies during the study period, in a pool of six, on a highly sensitive, Chemiluminiscent Microparticle Immunoassay (CMIA) based system. The screening test-reactive donors were recalled, counseled and interviewed, and a fresh sample was obtained for confirmatory testing. Confirmation was performed using additional immunoassays including Line Immunoassay (LIA); with additional testing for HTLV-1 pvDNAPCR. Frequency and percentages were determined. Four donors (0.19%) were repeatedly screening test-reactive and were subsequently confirmed to be HTLV-1 infected by line immunoassay and HTLV-1 pvDNAPCR. All four donors were male with mean age of 27 ± 6.27 years. Two (50%) of the positive donors gave history of Multiple Sexual Partners (MSP). HTLV-1 seroprevalence in Northern Pakistan blood donors was determined to be 0.19%. Large scale studies, including the cost effectiveness of screening blood donations for anti-HTLV-1/2 in Pakistan, are recommended.

  8. Storing Blood Cells

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The National Cancer Institute worked with Goddard Space Flight Center to propose a solution to the blood-cell freezing problem. White blood cells and bone marrow are stored for future use by leukemia patients as a result of Goddard and Jet Propulsion Laboratory expertise in electronics and cryogenics. White blood cell and bone marrow bank established using freezing unit. Freezing unit monitors temperature of cells themselves. Thermocouple placed against polyethylene container relays temperature signals to an electronic system which controls small heaters located outside container. Heaters allow liquid nitrogen to circulate at constant temperature and maintain consistent freezing rate. Ability to freeze, store, and thaw white cells and bone marrow without damage is important in leukemia treatment.

  9. [Change of Th22 cells in peripheral blood of patients with primary immune thrombocytopenia and clinical implication].

    PubMed

    Liu, Li-min; Zhang, Xing-xia; Zhao, Guang-sheng; Si, Ye-jun; Lin, Guo-qiang; Zhang, Yan-ming; He, Guang-sheng; Wu, De-pei

    2012-12-01

    To investigate the change of Th22 cells in the peripheral blood of the patients with primary immune thrombocytopenia (ITP) and evaluate the significance of Th22 cells in ITP. The proportion of Th22 cells in the peripheral blood of ITP patients before therapy (group 1), ITP patients in complete response after therapy (ITP-CR, group 2) and healthy donors (group 3) was evaluated by flow cytometry. The cytokines IL-22, TGF-β, TNF-α and IL-6 of each group were measured by ELISA. The level of IL-22 mRNA of each group was examined by RT-PCR. The proportion of Th22 cells and the levels of IL-22, TNF-α, IL-6 and IL-22 mRNA in group l and group 2 were significantly higher than those in group 3 (P<0.01). The proportion of Th22 cells and the levels of IL-22, TNF-α, IL-6 and IL-22 mRNA in group 2 were lower than those in group 1(P<0.05). But the level of TGF-β in group l [(3.27±1.02) ng/L] and group 2 [(5.41±1.69) ng/L] was significantly lower than that in group 3 [(9.65±2.78) ng/L] (P<0.01), and the level of TGF-β in group 1 was lower than that in group 2 (P<0.05). In ITP patients, the number of Th22 cells and the levels of TNF-α and IL-6 increase, and the level of TGF-β decrease.

  10. Low White Blood Cell Count

    MedlinePlus

    Symptoms Low white blood cell count By Mayo Clinic Staff A low white blood cell count (leukopenia) is a decrease in disease-fighting cells ( ... a decrease in a certain type of white blood cell (neutrophil). The definition of low white blood cell ...

  11. Human Flt3L generates dendritic cells from canine peripheral blood precursors: implications for a dog glioma clinical trial.

    PubMed

    Xiong, Weidong; Candolfi, Marianela; Liu, Chunyan; Muhammad, A K M Ghulam; Yagiz, Kader; Puntel, Mariana; Moore, Peter F; Avalos, Julie; Young, John D; Khan, Dorothy; Donelson, Randy; Pluhar, G Elizabeth; Ohlfest, John R; Wawrowsky, Kolja; Lowenstein, Pedro R; Castro, Maria G

    2010-06-11

    Glioblastoma multiforme (GBM) is the most common primary brain tumor in adults and carries a dismal prognosis. We have developed a conditional cytotoxic/immunotherapeutic approach using adenoviral vectors (Ads) encoding the immunostimulatory cytokine, human soluble fms-like tyrosine kinase 3 ligand (hsFlt3L) and the conditional cytotoxic molecule, i.e., Herpes Simplex Type 1- thymide kinase (TK). This therapy triggers an anti-tumor immune response that leads to tumor regression and anti-tumor immunological memory in intracranial rodent cancer models. We aim to test the efficacy of this immunotherapy in dogs bearing spontaneous GBM. In view of the controversy regarding the effect of human cytokines on dog immune cells, and considering that the efficacy of this treatment depends on hsFlt3L-stimulated dendritic cells (DCs), in the present work we tested the ability of Ad-encoded hsFlt3L to generate DCs from dog peripheral blood and compared its effects with canine IL-4 and GM-CSF. Our results demonstrate that hsFlT3L expressed form an Ad vector, generated DCs from peripheral blood cultures with very similar morphological and phenotypic characteristics to canine IL-4 and GM-CSF-cultured DCs. These include phagocytic activity and expression of CD11c, MHCII, CD80 and CD14. Maturation of DCs cultured under both conditions resulted in increased secretion of IL-6, TNF-alpha and IFN-gamma. Importantly, hsFlt3L-derived antigen presenting cells showed allostimulatory potential highlighting their ability to present antigen to T cells and elicit their proliferation. These results demonstrate that hsFlt3L induces the proliferation of canine DCs and support its use in upcoming clinical trials for canine GBM. Our data further support the translation of hsFlt3L to be used for dendritic cells' vaccination and gene therapeutic approaches from rodent models to canine patients and its future implementation in human clinical trials.

  12. Human Flt3L Generates Dendritic Cells from Canine Peripheral Blood Precursors: Implications for a Dog Glioma Clinical Trial

    PubMed Central

    Liu, Chunyan; Muhammad, A. K. M. Ghulam; Yagiz, Kader; Puntel, Mariana; Moore, Peter F.; Avalos, Julie; Young, John D.; Khan, Dorothy; Donelson, Randy; Pluhar, G. Elizabeth; Ohlfest, John R.; Wawrowsky, Kolja; Lowenstein, Pedro R.; Castro, Maria G.

    2010-01-01

    Background Glioblastoma multiforme (GBM) is the most common primary brain tumor in adults and carries a dismal prognosis. We have developed a conditional cytotoxic/immunotherapeutic approach using adenoviral vectors (Ads) encoding the immunostimulatory cytokine, human soluble fms-like tyrosine kinase 3 ligand (hsFlt3L) and the conditional cytotoxic molecule, i.e., Herpes Simplex Type 1- thymide kinase (TK). This therapy triggers an anti-tumor immune response that leads to tumor regression and anti-tumor immunological memory in intracranial rodent cancer models. We aim to test the efficacy of this immunotherapy in dogs bearing spontaneous GBM. In view of the controversy regarding the effect of human cytokines on dog immune cells, and considering that the efficacy of this treatment depends on hsFlt3L-stimulated dendritic cells (DCs), in the present work we tested the ability of Ad-encoded hsFlt3L to generate DCs from dog peripheral blood and compared its effects with canine IL-4 and GM-CSF. Methodology/Principal Findings Our results demonstrate that hsFlT3L expressed form an Ad vector, generated DCs from peripheral blood cultures with very similar morphological and phenotypic characteristics to canine IL-4 and GM-CSF-cultured DCs. These include phagocytic activity and expression of CD11c, MHCII, CD80 and CD14. Maturation of DCs cultured under both conditions resulted in increased secretion of IL-6, TNF-α and IFN-γ. Importantly, hsFlt3L-derived antigen presenting cells showed allostimulatory potential highlighting their ability to present antigen to T cells and elicit their proliferation. Conclusions/Significance These results demonstrate that hsFlt3L induces the proliferation of canine DCs and support its use in upcoming clinical trials for canine GBM. Our data further support the translation of hsFlt3L to be used for dendritic cells' vaccination and gene therapeutic approaches from rodent models to canine patients and its future implementation in human clinical

  13. Red blood cells, sickle cell (image)

    MedlinePlus

    ... is an inherited blood disease in which the red blood cells produce abnormal pigment (hemoglobin). The abnormal hemoglobin causes deformity of the red blood cells into crescent or sickle-shapes, as seen in ...

  14. Fluorescent blood cell angiography

    NASA Astrophysics Data System (ADS)

    Ben-nun, Joshua; Constable, Ian J.

    1994-06-01

    Fluorescein angiography is currently the main method for evaluation of the retinal vascular patency. Ashton noted that capillary patency to the small fluorescein molecule may differ from that of the larger red blood cells. He concluded that fluorescein angiography is not able to demonstrate a developing stenosis, that might be the precipitating cause of a later capillary closure in various microvasculopathies. Sarelius et al have shown, in hamster cheek pouch and cremaster muscle, that fluorescently labeled erythrocytes in known concentrations can be used for the direct measurement of capillary flow parameters. The only assumption that this method relies on, is that the labeled cells are rheologically normal and therefore reflect the behavior of the total cell population. We have developed a new method for an in-vivo, real-time demonstration of the blood cell flow in the retinal capillary net. Based on the assumption presented by Sarelius et al, measurement and analysis of the retinal capillary blood cell flow is also possible from the results achieved by the new method.

  15. High-dose mitoxantrone with peripheral blood progenitor cell rescue: toxicity, pharmacokinetics and implications for dosage and schedule.

    PubMed Central

    Ballestrero, A.; Ferrando, F.; Garuti, A.; Basta, P.; Gonella, R.; Esposito, M.; Vannozzi, M. O.; Sorice, G.; Friedman, D.; Puglisi, M.; Brema, F.; Mela, G. S.; Sessarego, M.; Patrone, F.

    1997-01-01

    The optimal use of mitoxantrone (NOV) in the high-dose range requires elucidation of its maximum tolerated dose with peripheral blood progenitor cell (PBPC) support and the time interval needed between drug administration and PBPC reinfusion in order to avoid graft toxicity. The aims of this study were: (1) to verify the feasibility and haematological toxicity of escalating NOV up to 90 mg m(-2) with PBPC support; and (2) to verify the safeness of a short (96 h) interval between NOV administration and PBPC reinfusion. Three cohorts of ten patients with breast cancer (BC) or non-Hodgkin's lymphoma (NHL) received escalating doses of NOV, 60, 75 and 90 mg m(-2) plus melphalan (L-PAM), 140-180 mg m(-2), with PBPC rescue 96 h after NOV. Haematological toxicity was evaluated daily (WHO criteria). NOV plasma pharmacokinetics was also evaluated, as well as NOV cytotoxicity against PBPCs. Haematological recovery was rapid and complete at each NOV dose level without statistically significant differences, and there were no major toxicities. NOV plasma concentrations at the time of PBPC reinfusion were below the toxicity threshold against haemopoietic progenitors. It is concluded that, when adequately supported with PBPCs, NOV can be escalated up to 90 mg m(-2) with acceptable haematological toxicity. PBPCs can be safely reinfused as early as 96 h after NOV administration. PMID:9310249

  16. Systemic sclerosis sera affect fibrillin-1 deposition by dermal blood microvascular endothelial cells: therapeutic implications of cyclophosphamide

    PubMed Central

    2013-01-01

    Introduction Systemic sclerosis (SSc) is a connective tissue disorder characterized by endothelial cell injury, autoimmunity and fibrosis. The following three fibrillin-1 alterations have been reported in SSc. (1) Fibrillin-1 microfibrils are disorganized in SSc dermis. (2) Fibrillin-1 microfibrils produced by SSc fibroblasts are unstable. (3) Mutations in the FBN1 gene and anti-fibrillin-1 autoantibodies have been reported in SSc. Fibrillin-1 microfibrils, which are abundantly produced by blood and lymphatic microvascular endothelial cells (B-MVECs and Ly-MVECs, respectively), sequester in the extracellular matrix the latent form of the potent profibrotic cytokine transforming growth factor β (TGF-β). In the present study, we evaluated the effects of SSc sera on the deposition of fibrillin-1 and microfibril-associated glycoprotein 1 (MAGP-1) and the expression of focal adhesion molecules by dermal B-MVECs and Ly-MVECs. Methods Dermal B-MVECs and Ly-MVECs were challenged with sera from SSc patients who were treatment-naïve or under cyclophosphamide (CYC) treatment and with sera from healthy controls. Fibrillin-1/MAGP-1 synthesis and deposition and the expression of αvβ3 integrin/phosphorylated focal adhesion kinase and vinculin/actin were evaluated by immunofluorescence and quantified by morphometric analysis. Results Fibrillin-1 and MAGP-1 colocalized in all experimental conditions, forming a honeycomb pattern in B-MVECs and a dense mesh of short segments in Ly-MVECs. In B-MVECs, fibrillin-1/MAGP-1 production and αvβ3 integrin expression significantly decreased upon challenge with sera from naïve SSc patients compared with healthy controls. Upon challenge of B-MVECs with sera from CYC-treated SSc patients, fibrillin-1/MAGP-1 and αvβ3 integrin levels were comparable to those of cells treated with healthy sera. Ly-MVECs challenged with SSc sera did not differ from those treated with healthy control sera in the expression of any of the molecules assayed

  17. Red blood cells, multiple sickle cells (image)

    MedlinePlus

    Sickle cell anemia is an inherited disorder in which abnormal hemoglobin (the red pigment inside red blood cells) is produced. The abnormal hemoglobin causes red blood cells to assume a sickle shape, like the ones seen in this photomicrograph.

  18. Blood dendritic cell levels associated with impaired IL-12 production and T-cell deficiency in patients with kidney disease: implications for post-transplant viral infections.

    PubMed

    Chen, Ping; Sun, Qianmei; Huang, Yanfei; Atta, Mohamed G; Turban, Sharon; Segev, Dorry L; Marr, Kieren A; Naqvi, Fizza F; Alachkar, Nada; Kraus, Edward S; Womer, Karl L

    2014-10-01

    Reduced pretransplant blood myeloid dendritic cell (mDC) levels are associated with post-transplant BK viremia and cytomegalovirus (CMV) disease after kidney transplantation. To elucidate potential mechanisms by which mDC levels might influence these outcomes, we studied the association of mDC levels with mDC IL-12 production and T-cell level/function. Peripheral blood (PB) was studied in three groups: (i) end stage renal disease patients on hemodialysis (HD; n = 81); (ii) chronic kidney disease stage IV-V patients presenting for kidney transplant evaluation or the day of transplantation (Eval/Tx; n = 323); and (iii) healthy controls (HC; n = 22). Along with a statistically significant reduction in mDC levels, reduced CD8(+) T-cell levels were also demonstrated in the kidney disease groups compared with HC. Reduced PB mDC and monocyte-derived DC (MoDC) IL-12 production was observed after in vitro LPS stimulation in the HD versus HC groups. Finally, ELISpot assays demonstrated less robust CD3(+) INF-γ responses by MoDCs pulsed with CMV pp65 peptide from HD patients compared with HC. PB mDC level deficiency in patients with kidney disease is associated with deficient IL-12 production and T-cell level/function, which may explain the known correlation of CD8(+) T-cell lymphopenia with deficient post-transplant antiviral responses. © 2014 Steunstichting ESOT.

  19. Dog Red Blood Cells

    PubMed Central

    Parker, John C.

    1973-01-01

    Dog red blood cells (RBC) lack a ouabain-sensitive sodium pump, and yet they are capable of volume regulation in vivo. The present study was designed to find in vitro conditions under which dog RBC could transport sodium outward, against an electrochemical gradient. Cells were first loaded with sodium chloride and water by preincubation in hypertonic saline. They were then incubated at 37°C in media containing physiologic concentrations of sodium, potassium, chloride, bicarbonate, glucose, and calcium. The cells returned to a normal salt and water content in 16–20 h. Without calcium in the medium the cells continued slowly to accumulate sodium. Removal of glucose caused rapid swelling and lysis, whether or not calcium was present. The net efflux of sodium showed a close relationship to medium calcium over a concentration range from 0 to 5 mM. Extrusion of salt and water was also demonstrated in fresh RBC (no hypertonic preincubation) when calcium levels in the media were sufficiently raised. The ion and water movements in these experiments were not influenced by ouabain or by removal of extracellular potassium. Magnesium could not substitute for calcium. It is concluded that dog RBC have an energy-dependent mechanism for extruding sodium chloride which requires external calcium and is quite distinct from the sodium-potassium exchange pump. PMID:4722565

  20. Red Blood Cell Antibody Identification

    MedlinePlus

    ... name: Red Blood Cell Antibody Identification Related tests: Direct Antiglobulin Test ; RBC Antibody Screen ; Blood Typing ; Type ... a positive RBC antibody screen or a positive direct antiglobulin test (DAT) . It is used to identify ...

  1. Cell-Specific Variation in E-Selectin Ligand Expression among Human Peripheral Blood Mononuclear Cells: Implications for Immunosurveillance and Pathobiology.

    PubMed

    Silva, Mariana; Fung, Ronald Kam Fai; Donnelly, Conor Brian; Videira, Paula Alexandra; Sackstein, Robert

    2017-03-22

    Both host defense and immunopathology are shaped by the ordered recruitment of circulating leukocytes to affected sites, a process initiated by binding of blood-borne cells to E-selectin displayed at target endothelial beds. Accordingly, knowledge of the expression and function of leukocyte E-selectin ligands is key to understanding the tempo and specificity of immunoreactivity. In this study, we performed E-selectin adherence assays under hemodynamic flow conditions coupled with flow cytometry and Western blot analysis to elucidate the function and structural biology of glycoprotein E-selectin ligands expressed on human PBMCs. Circulating monocytes uniformly express high levels of the canonical E-selectin binding determinant sialyl Lewis X (sLe(X)) and display markedly greater adhesive interactions with E-selectin than do circulating lymphocytes, which exhibit variable E-selectin binding among CD4(+) and CD8(+) T cells but no binding by B cells. Monocytes prominently present sLe(X) decorations on an array of protein scaffolds, including P-selectin glycoprotein ligand-1, CD43, and CD44 (rendering the E-selectin ligands cutaneous lymphocyte Ag, CD43E, and hematopoietic cell E-selectin/L-selectin ligand, respectively), and B cells altogether lack E-selectin ligands. Quantitative PCR gene expression studies of glycosyltransferases that regulate display of sLe(X) reveal high transcript levels among circulating monocytes and low levels among circulating B cells, and, commensurately, cell surface α(1,3)-fucosylation reveals that acceptor sialyllactosaminyl glycans convertible into sLe(X) are abundantly expressed on human monocytes yet are relatively deficient on B cells. Collectively, these findings unveil distinct cell-specific patterns of E-selectin ligand expression among human PBMCs, indicating that circulating monocytes are specialized to engage E-selectin and providing key insights into the molecular effectors mediating recruitment of these cells at inflammatory

  2. Porphyrin binding with blood cells

    NASA Astrophysics Data System (ADS)

    Zorin, Vladimir P.; Khludeyev, Ivan I.; Savitsky, Valery P.; Mel'nov, Sergey B.; Kochubeyeva, Nina D.

    1997-12-01

    Using fluorescence activated cell sorting we have compared the binding of a number of porphyrins with different polarity by blood cells. According to pigment level blood cells may be arranged in order granulocytes greater than or equal to monocytes greater than lymphocytes greater than erythrocytes. Cellular accumulation of selected porphyrins in blood cells was remarkably different. The equilibrium level of chlorin e6 dimethylester in blood cells was about 15 times higher compared with chlorin e6. As a result, the percentage of pigment binding by blood cells varied from 0% (of total amount) in the case of polar pigments to about 50% for moderately apolar porphyrins. The results obtained show that pigment binding to blood cells may be of certain value when the pharmacokinetic behavior of porphyrin sensitizer is analyzed.

  3. Clinical implications of positive blood cultures.

    PubMed Central

    Bryan, C S

    1989-01-01

    Positive blood cultures can be classified according to their veracity (true-positive or false-positive culture), clinical severity (inconsequential or life threatening), place of origin (community acquired or nosocomial), source (primary or secondary), duration (transient, intermittent, or continuous), pattern of occurrence (single episode, persistent, or recurrent), or intensity (high or low grade). In general, however, positive blood cultures identify a patient population at high risk of death. In my studies, patients with positive blood cultures were 12 times more likely to die during hospitalization than patients without positive blood cultures. Many bacteremias and fungemias occur in complicated clinical settings, and it appears that only about one-half of the deaths among affected patients are due directly to infection. Hence, it is appropriate to speak of "crude mortality" and "attributable mortality." Among hospitalized patients, recent trends include rising incidences of Staphylococcus aureus and coagulase-negative staphylococcal and enterococcal bacteremias and a dramatic increase in the incidence of fungemias. The diagnostic and therapeutic implications of blood cultures positive for specific microorganisms continue to evolve and are the subject of a large and growing medical literature. PMID:2680055

  4. The Distribution of HIV DNA and RNA in Cell Subsets Differs in Gut and Blood of HIV-Positive Patients on ART: Implications for Viral Persistence

    PubMed Central

    Yukl, Steven A.; Shergill, Amandeep K.; Ho, Terence; Killian, Maudi; Girling, Valerie; Epling, Lorrie; Li, Peilin; Wong, Lisa K.; Crouch, Pierre; Deeks, Steven G.; Havlir, Diane V.; McQuaid, Kenneth; Sinclair, Elizabeth; Wong, Joseph K.

    2013-01-01

    Even with optimal antiretroviral therapy, human immunodeficiency virus (HIV) persists in plasma, blood cells, and tissues. To develop new therapies, it is essential to know what cell types harbor residual HIV. We measured levels of HIV DNA, RNA, and RNA/DNA ratios in sorted subsets of CD4+ T cells (CCR7+, transitional memory, and effector memory) and non-CD4+ T leukocytes from blood, ileum, and rectum of 8 ART-suppressed HIV-positive subjects. Levels of HIV DNA/million cells in CCR7+ and effector memory cells were higher in the ileum than blood. When normalized by cell frequencies, most HIV DNA and RNA in the blood were found in CCR7+ cells, whereas in both gut sites, most HIV DNA and RNA were found in effector memory cells. HIV DNA and RNA were observed in non-CD4+ T leukocytes at low levels, particularly in gut tissues. Compared to the blood, the ileum had higher levels of HIV DNA and RNA in both CD4+ T cells and non-CD4+ T leukocytes, whereas the rectum had higher HIV DNA levels in both cell types but lower RNA levels in CD4+ T cells. Future studies should determine whether different mechanisms allow HIV to persist in these distinct reservoirs, and the degree to which different therapies can affect each reservoir. PMID:23852128

  5. The distribution of HIV DNA and RNA in cell subsets differs in gut and blood of HIV-positive patients on ART: implications for viral persistence.

    PubMed

    Yukl, Steven A; Shergill, Amandeep K; Ho, Terence; Killian, Maudi; Girling, Valerie; Epling, Lorrie; Li, Peilin; Wong, Lisa K; Crouch, Pierre; Deeks, Steven G; Havlir, Diane V; McQuaid, Kenneth; Sinclair, Elizabeth; Wong, Joseph K

    2013-10-15

    Even with optimal antiretroviral therapy, human immunodeficiency virus (HIV) persists in plasma, blood cells, and tissues. To develop new therapies, it is essential to know what cell types harbor residual HIV. We measured levels of HIV DNA, RNA, and RNA/DNA ratios in sorted subsets of CD4+ T cells (CCR7+, transitional memory, and effector memory) and non-CD4+ T leukocytes from blood, ileum, and rectum of 8 ART-suppressed HIV-positive subjects. Levels of HIV DNA/million cells in CCR7+ and effector memory cells were higher in the ileum than blood. When normalized by cell frequencies, most HIV DNA and RNA in the blood were found in CCR7+ cells, whereas in both gut sites, most HIV DNA and RNA were found in effector memory cells. HIV DNA and RNA were observed in non-CD4+ T leukocytes at low levels, particularly in gut tissues. Compared to the blood, the ileum had higher levels of HIV DNA and RNA in both CD4+ T cells and non-CD4+ T leukocytes, whereas the rectum had higher HIV DNA levels in both cell types but lower RNA levels in CD4+ T cells. Future studies should determine whether different mechanisms allow HIV to persist in these distinct reservoirs, and the degree to which different therapies can affect each reservoir.

  6. [Development of blood cell measurement].

    PubMed

    Okada, T

    2000-10-01

    Automated blood cell analyzers used in hematology laboratories are required to measure many specimens rapidly and efficiency has been realized through increasing the measurement parameters and throughput volume in one instrument. In the period of 1950's through the early part of 1960's, only red blood cells and white blood cells could be counted. In 1965, Technicon Corporation developed an instrument which can measure the number of blood cells, hemoglobin, hematocrit and calculate corpuscular constants simultaneously. Thereafter, the methodologies for simultaneous platelet measurement and precise determination of blood cell distribution have been developed. Then, the development of new reagents has achieved three part differentials in the distribution of white blood cells. Thanks to this development, microscopic white blood cell differentials has been replaced by blood cell analyzers in screening tests. Though blood cell analyzers may be further improved by expanding of the number of parameters available for simultaneous measurements, meeting social needs in the new era will not be possible without the creation and realization of new concepts employing new technologies such as IT (Information Technology).

  7. Genetic effects on variation in red-blood-cell folate in adults: Implications for the familial aggregation of neural tube defects

    SciTech Connect

    Mitchell, L.E.; Duffy, P.; Bellingham, G.

    1997-02-01

    Recent studies have implicated folic acid as an important determinant of normal human growth, development, and function. Insufficient folate levels appear to be a risk factor for neural tube defects (NTD), as well as for several chronic diseases of adulthood. However, relatively little is known about the factors that influence folate status in the general population. To estimate the relative contribution of genetic and nongenetic factors to variation in folate, we have evaluated red blood cell (RBC) folate levels in 440 pairs of MZ twins and in 331 pairs of DZ twins. The data were best described by a model in which 46% of the variance in RBC folate was attributable to additive genetic effects, 16% of the variance was due to measured phenotypic covariates, and 38% of the variance was due to random environmental effects. Moreover, the correlations for RBC folate in MZ co-twins (r = .46) and in repeat measures from the same individual (r = .51) were very similar, indicating that virtually all repeatable variation in RBC folate is attributable to genetic factors. On the basis of these results, it would seem reasonable to initiate a search for the specific genes that influence RBC folate levels in the general population. Such genes ultimately may be used to identify individuals at increased risk for NTD and other folate-related diseases. 23 refs., 1 tab.

  8. Expression of the Kynurenine Pathway in Human Peripheral Blood Mononuclear Cells: Implications for Inflammatory and Neurodegenerative Disease.

    PubMed

    Jones, Simon P; Franco, Nunzio F; Varney, Bianca; Sundaram, Gayathri; Brown, David A; de Bie, Josien; Lim, Chai K; Guillemin, Gilles J; Brew, Bruce J

    2015-01-01

    The kynurenine pathway is a fundamental mechanism of immunosuppression and peripheral tolerance. It is increasingly recognized as playing a major role in the pathogenesis of a wide variety of inflammatory, neurodegenerative and malignant disorders. However, the temporal dynamics of kynurenine pathway activation and metabolite production in human immune cells is currently unknown. Here we report the novel use of flow cytometry, combined with ultra high-performance liquid chromatography and gas chromatography-mass spectrometry, to sensitively quantify the intracellular expression of three key kynurenine pathway enzymes and the main kynurenine pathway metabolites in a time-course study. This is the first study to show that up-regulation of indoleamine 2,3-dioxygenase (IDO-1), kynurenine 3-monoxygenase (KMO) and quinolinate phosphoribosyltransferase (QPRT) is lacking in lymphocytes treated with interferon gamma. In contrast, peripheral monocytes showed a significant elevation of kynurenine pathway enzymes and metabolites when treated with interferon gamma. Expression of IDO-1, KMO and QPRT correlated significantly with activation of the kynurenine pathway (kynurenine:tryptophan ratio), quinolinic acid concentration and production of the monocyte derived, pro-inflammatory immune response marker: neopterin. Our results also describe an original and sensitive methodological approach to quantify kynurenine pathway enzyme expression in cells. This has revealed further insights into the potential role of these enzymes in disease processes.

  9. Expression of the Kynurenine Pathway in Human Peripheral Blood Mononuclear Cells: Implications for Inflammatory and Neurodegenerative Disease

    PubMed Central

    Jones, Simon P.; Franco, Nunzio F.; Varney, Bianca; Sundaram, Gayathri; Brown, David A.; de Bie, Josien; Lim, Chai K.; Guillemin, Gilles J.; Brew, Bruce J.

    2015-01-01

    The kynurenine pathway is a fundamental mechanism of immunosuppression and peripheral tolerance. It is increasingly recognized as playing a major role in the pathogenesis of a wide variety of inflammatory, neurodegenerative and malignant disorders. However, the temporal dynamics of kynurenine pathway activation and metabolite production in human immune cells is currently unknown. Here we report the novel use of flow cytometry, combined with ultra high-performance liquid chromatography and gas chromatography-mass spectrometry, to sensitively quantify the intracellular expression of three key kynurenine pathway enzymes and the main kynurenine pathway metabolites in a time-course study. This is the first study to show that up-regulation of indoleamine 2,3-dioxygenase (IDO-1), kynurenine 3-monoxygenase (KMO) and quinolinate phosphoribosyltransferase (QPRT) is lacking in lymphocytes treated with interferon gamma. In contrast, peripheral monocytes showed a significant elevation of kynurenine pathway enzymes and metabolites when treated with interferon gamma. Expression of IDO-1, KMO and QPRT correlated significantly with activation of the kynurenine pathway (kynurenine:tryptophan ratio), quinolinic acid concentration and production of the monocyte derived, pro-inflammatory immune response marker: neopterin. Our results also describe an original and sensitive methodological approach to quantify kynurenine pathway enzyme expression in cells. This has revealed further insights into the potential role of these enzymes in disease processes. PMID:26114426

  10. [Hepatitis E virus: Blood transfusion implications].

    PubMed

    Gallian, P; Piquet, Y; Assal, A; Djoudi, R; Chiaroni, J; Izopet, J; Tiberghien, P

    2014-11-01

    Hepatitis E virus (HEV) is a non-enveloped RNA virus transmitted by the fecal-oral route. Autochthonous hepatitis E occurring in developed countries is caused by genotypes 3 and 4 and is a zoonotic infection. Humans are infected mostly after ingestion of undercooked meat from infected animals. Most HEV 3 and 4 infections are clinically inapparent. However, genotype 3 (HEV 3) can lead to chronic hepatitis in immuno-compromised patients such as organ-transplant recipients and patients with haematological malignancies. In Europe, HEV 3 is implicated in transfusion-transmitted HEV infection. In France, as observed in several European countries, prevalence of HEV RNA and specific IgG antibodies are high indicating that viral circulation is important. The systematic HEV NAT screening of blood donations used for preparation of solvent detergent plasma indicate that 1 to 2218 donation is infected by HEV RNA. The need or implementation's impacts of safety measures to prevent HEV transmission by blood transfusion are under reflexion by French's health authorities. The HEV NAT screening is the only available tool of prevention. Alternative strategies are under investigation including individual or mini pool NAT testing all or part of blood donations. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  11. Deformability of Tumor Cells versus Blood Cells

    PubMed Central

    Shaw Bagnall, Josephine; Byun, Sangwon; Begum, Shahinoor; Miyamoto, David T.; Hecht, Vivian C.; Maheswaran, Shyamala; Stott, Shannon L.; Toner, Mehmet; Hynes, Richard O.; Manalis, Scott R.

    2015-01-01

    The potential for circulating tumor cells (CTCs) to elucidate the process of cancer metastasis and inform clinical decision-making has made their isolation of great importance. However, CTCs are rare in the blood, and universal properties with which to identify them remain elusive. As technological advancements have made single-cell deformability measurements increasingly routine, the assessment of physical distinctions between tumor cells and blood cells may provide insight into the feasibility of deformability-based methods for identifying CTCs in patient blood. To this end, we present an initial study assessing deformability differences between tumor cells and blood cells, indicated by the length of time required for them to pass through a microfluidic constriction. Here, we demonstrate that deformability changes in tumor cells that have undergone phenotypic shifts are small compared to differences between tumor cell lines and blood cells. Additionally, in a syngeneic mouse tumor model, cells that are able to exit a tumor and enter circulation are not required to be more deformable than the cells that were first injected into the mouse. However, a limited study of metastatic prostate cancer patients provides evidence that some CTCs may be more mechanically similar to blood cells than to typical tumor cell lines. PMID:26679988

  12. Umbilical cord blood banking: implications for perinatal care providers.

    PubMed

    Armson, B Anthony

    2005-03-01

    To evaluate the risks and benefits of umbilical cord blood banking for future stem cell transplantation and to provide guidelines for Canadian perinatal care providers regarding the counselling, procedural, and ethical implications of this potential therapeutic option. Selective or routine collection and storage of umbilical cord blood for future autologous (self) or allogenic (related or unrelated) transplantation of hematopoietic stem cells to treat malignant and nonmalignant disorders in children and adults. Maternal and perinatal morbidity, indications for umbilical cord blood transplantation, short- and long-term risks and benefits of umbilical cord blood transplantation, burden of umbilical cord blood collection on perinatal care providers, parental satisfaction, and health care costs. MEDLINE and PubMed searches were conducted from January 1970 to October 2003 for English-language articles related to umbilical cord blood collection, banking, and transplantation; the Cochrane library was searched; and committee opinions of the Royal College of Obstetricians and Gynaecologists, the American Academy of Pediatrics, and the American College of Obstetricians and Gynecologists were obtained. The evidence collected was reviewed and evaluated by the Maternal/Fetal Medicine Committee of the Society of Obstetricians and Gynaecologists of Canada (SOGC), and recommendations were made using the evaluation of evidence guidelines developed by the Canadian Task Force on the Periodic Health Exam. Umbilical cord blood is a readily available source of hematopoietic stem cells used with increasing frequency as an alternative to bone marrow or peripheral stem cells for transplantation in the treatment of malignant and nonmalignant conditions in children and adults. Umbilical cord blood transplantation provides a rich source of hematopoietic stem cells with several advantages, including prompt availability, decreased risk of transmissible viral infections and graft

  13. Red blood cells, spherocytosis (image)

    MedlinePlus

    Spherocytosis is a hereditary disorder of the red blood cells (RBCs), which may be associated with a mild anemia. Typically, the affected RBCs are small, spherically shaped, and lack the light centers seen ...

  14. Correlation of umbilical cord blood hormones and growth factors with stem cell potential: implications for the prenatal origin of breast cancer hypothesis

    PubMed Central

    Savarese, Todd M; Strohsnitter, William C; Low, Hoi Pang; Liu, Qin; Baik, Inkyung; Okulicz, William; Chelmow, David P; Lagiou, Pagona; Quesenberry, Peter J; Noller, Kenneth L; Hsieh, Chung-Cheng

    2007-01-01

    Introduction Prenatal levels of mitogens may influence the lifetime breast cancer risk by driving stem cell proliferation and increasing the number of target cells, and thereby increasing the chance of mutation events that initiate oncogenesis. We examined in umbilical cord blood the correlation of potential breast epithelial mitogens, including hormones and growth factors, with hematopoietic stem cell concentrations serving as surrogates of overall stem cell potential. Methods We analyzed cord blood samples from 289 deliveries. Levels of hormones and growth factors were correlated with concentrations of stem cell and progenitor populations (CD34+ cells, CD34+CD38- cells, CD34+c-kit+ cells, and granulocyte–macrophage colony-forming units). Changes in stem cell concentration associated with each standard deviation change in mitogens and the associated 95% confidence intervals were calculated from multiple regression analysis. Results Cord blood plasma levels of insulin-like growth factor-1 (IGF-1) were strongly correlated with all the hematopoietic stem and progenitor concentrations examined (one standard-deviation increase in IGF-1 being associated with a 15–19% increase in stem/progenitor concentrations, all P < 0.02). Estriol and insulin-like growth factor binding protein-3 levels were positively and significantly correlated with some of these cell populations. Sex hormone-binding globulin levels were negatively correlated with these stem/progenitor pools. These relationships were stronger in Caucasians and Hispanics and were weaker or not present in Asian-Americans and African-Americans. Conclusion Our data support the concept that in utero mitogens may drive the expansion of stem cell populations. The correlations with IGF-1 and estrogen are noteworthy, as both are crucial for mammary gland development. PMID:17501995

  15. Blood cells and endothelial barrier function

    PubMed Central

    Rodrigues, Stephen F; Granger, D Neil

    2015-01-01

    Abstract The barrier properties of endothelial cells are critical for the maintenance of water and protein balance between the intravascular and extravascular compartments. An impairment of endothelial barrier function has been implicated in the genesis and/or progression of a variety of pathological conditions, including pulmonary edema, ischemic stroke, neurodegenerative disorders, angioedema, sepsis and cancer. The altered barrier function in these conditions is often linked to the release of soluble mediators from resident cells (e.g., mast cells, macrophages) and/or recruited blood cells. The interaction of the mediators with receptors expressed on the surface of endothelial cells diminishes barrier function either by altering the expression of adhesive proteins in the inter-endothelial junctions, by altering the organization of the cytoskeleton, or both. Reactive oxygen species (ROS), proteolytic enzymes (e.g., matrix metalloproteinase, elastase), oncostatin M, and VEGF are part of a long list of mediators that have been implicated in endothelial barrier failure. In this review, we address the role of blood borne cells, including, neutrophils, lymphocytes, monocytes, and platelets, in the regulation of endothelial barrier function in health and disease. Attention is also devoted to new targets for therapeutic intervention in disease states with morbidity and mortality related to endothelial barrier dysfunction. PMID:25838983

  16. Paracrine proangiopoietic effects of human umbilical cord blood-derived purified CD133+ cells--implications for stem cell therapies in regenerative medicine.

    PubMed

    Ratajczak, Janina; Kucia, Magda; Mierzejewska, Kasia; Marlicz, Wojciech; Pietrzkowski, Zbigniew; Wojakowski, Wojciech; Greco, Nicholas J; Tendera, Michal; Ratajczak, Mariusz Z

    2013-02-01

    CD133+ cells purified from hematopoietic tissues are enriched mostly for hematopoietic stem/progenitor cells, but also contain some endothelial progenitor cells and very small embryonic-like stem cells. CD133+ cells, which are akin to CD34+ cells, are a potential source of stem cells in regenerative medicine. However, the lack of convincing donor-derived chimerism in the damaged organs of patients treated with these cells suggests that the improvement in function involves mechanisms other than a direct contribution to the damaged tissues. We hypothesized that CD133+ cells secrete several paracrine factors that play a major role in the positive effects observed after treatment and tested supernatants derived from these cells for the presence of such factors. We observed that CD133+ cells and CD133+ cell-derived microvesicles (MVs) express mRNAs for several antiapoptotic and proangiopoietic factors, including kit ligand, insulin growth factor-1, vascular endothelial growth factor, basic fibroblast growth factor, and interleukin-8. These factors were also detected in a CD133+ cell-derived conditioned medium (CM). More important, the CD133+ cell-derived CM and MVs chemoattracted endothelial cells and display proangiopoietic activity both in vitro and in vivo assays. This observation should be taken into consideration when evaluating clinical outcomes from purified CD133+ cell therapies in regenerative medicine.

  17. Red Blood Cell Magnetophoresis

    PubMed Central

    Zborowski, Maciej; Ostera, Graciela R.; Moore, Lee R.; Milliron, Sarah; Chalmers, Jeffrey J.; Schechter, Alan N.

    2003-01-01

    The existence of unpaired electrons in the four heme groups of deoxy and methemoglobin (metHb) gives these species paramagnetic properties as contrasted to the diamagnetic character of oxyhemoglobin. Based on the measured magnetic moments of hemoglobin and its compounds, and on the relatively high hemoglobin concentration of human erythrocytes, we hypothesized that differential migration of these cells was possible if exposed to a high magnetic field. With the development of a new technology, cell tracking velocimetry, we were able to measure the migration velocity of deoxygenated and metHb-containing erythrocytes, exposed to a mean magnetic field of 1.40 T and a mean gradient of 0.131 T/mm, in a process we call cell magnetophoresis. Our results show a similar magnetophoretic mobility of 3.86 × 10−6 mm3 s/kg for erythrocytes with 100% deoxygenated hemoglobin and 3.66 × 10−6 mm3 s/kg for erythrocytes containing 100% metHb. Oxygenated erythrocytes had a magnetophoretic mobility of from −0.2 × 10−6 mm3 s/kg to +0.30 × 10−6 mm3 s/kg, indicating a significant diamagnetic component relative to the suspension medium, in agreement with previous studies on the hemoglobin magnetic susceptibility. Magnetophoresis may open up an approach to characterize and separate cells for biochemical analysis based on intrinsic and extrinsic magnetic properties of biological macromolecules. PMID:12668472

  18. Red blood cell magnetophoresis.

    PubMed

    Zborowski, Maciej; Ostera, Graciela R; Moore, Lee R; Milliron, Sarah; Chalmers, Jeffrey J; Schechter, Alan N

    2003-04-01

    The existence of unpaired electrons in the four heme groups of deoxy and methemoglobin (metHb) gives these species paramagnetic properties as contrasted to the diamagnetic character of oxyhemoglobin. Based on the measured magnetic moments of hemoglobin and its compounds, and on the relatively high hemoglobin concentration of human erythrocytes, we hypothesized that differential migration of these cells was possible if exposed to a high magnetic field. With the development of a new technology, cell tracking velocimetry, we were able to measure the migration velocity of deoxygenated and metHb-containing erythrocytes, exposed to a mean magnetic field of 1.40 T and a mean gradient of 0.131 T/mm, in a process we call cell magnetophoresis. Our results show a similar magnetophoretic mobility of 3.86 x 10(-6) mm(3) s/kg for erythrocytes with 100% deoxygenated hemoglobin and 3.66 x 10(-6) mm(3) s/kg for erythrocytes containing 100% metHb. Oxygenated erythrocytes had a magnetophoretic mobility of from -0.2 x 10(-6) mm(3) s/kg to +0.30 x 10(-6) mm(3) s/kg, indicating a significant diamagnetic component relative to the suspension medium, in agreement with previous studies on the hemoglobin magnetic susceptibility. Magnetophoresis may open up an approach to characterize and separate cells for biochemical analysis based on intrinsic and extrinsic magnetic properties of biological macromolecules.

  19. Cyclophosphamide induces a type I interferon-associated sterile inflammatory response signature in cancer patients' blood cells: implications for cancer chemoimmunotherapy.

    PubMed

    Moschella, Federica; Torelli, Giovanni Fernando; Valentini, Mara; Urbani, Francesca; Buccione, Carla; Petrucci, Maria Teresa; Natalino, Fiammetta; Belardelli, Filippo; Foà, Robin; Proietti, Enrico

    2013-08-01

    Certain chemotherapeutics, particularly cyclophosphamide, can enhance the antitumor efficacy of immunotherapy. A better understanding of the cellular and molecular basis of cyclophosphamide-mediated immunomodulation is needed to improve the efficacy of chemoimmunotherapy. Transcript profiling and flow cytometry were used to explore cyclophosphamide-induced immunoadjuvanticity in patients with hematologic malignancies. A single high-dose treatment rapidly (1-2 days) induced peripheral blood mononuclear cell (PBMC) transcriptional modulation, leading to reduction of cell-cycle and biosynthetic/metabolic processes and augmentation of DNA damage and cell death pathways (p53 signaling pathway), death-related scavenger receptors, antigen processing/presentation mediators, T-cell activation markers and, noticeably, a type I IFN (IFN-I) signature (OAS1, CXCL10, BAFF, IFITM2, IFI6, IRF5, IRF7, STAT2, UBE2L6, UNC93B1, ISG20L1, TYK2). Moreover, IFN-I-induced proinflammatory mediators (CXCL10, CCL2, IL-8, and BAFF) were increased in patients' plasma. Accordingly, cyclophosphamide induced the expansion/activation of CD14(+)CD16(+) monocytes, of HLA-DR(+), IL-8RA(+), and MARCO(+) monocytes/dendritic cells, and of CD69(+), OX40(+), and IL-8RA(+) lymphocytes. Altogether, these data identify the cyclophosphamide-induced immunomodulatory factors in humans and indicate that preconditioning chemotherapy may stimulate immunity as a consequence of danger perception associated with blood cell death, through p53 and IFN-I-related mechanisms. ©2013 AACR.

  20. Cell-free fetal DNA and intact fetal cells in maternal blood circulation: implications for first and second trimester non-invasive prenatal diagnosis.

    PubMed

    Bischoff, Farideh Z; Sinacori, Mina K; Dang, Dianne D; Marquez-Do, Deborah; Horne, Cassandra; Lewis, Dorothy E; Simpson, Joe Leigh

    2002-01-01

    Both intact fetal cells as well as cell-free fetal DNA are present in the maternal circulation and can be recovered for non-invasive prenatal genetic diagnosis. Although methods for enrichment and isolation of rare intact fetal cells have been challenging, diagnosis of fetal chromosomal aneuploidy including trisomy 21 in first- and second-trimester pregnancies has been achieved with a 50-75% detection rate. Similarly, cell-free fetal DNA can be reliably recovered from maternal plasma and assessed by quantitative PCR to detect fetal trisomy 21 and paternally derived single gene mutations. Real-time PCR assays are robust in detecting low-level fetal DNA concentrations, with sensitivity of approximately 95-100% and specificity near 100%. Comparing intact fetal cell versus cell-free fetal DNA methods for non-invasive prenatal screening for fetal chromosomal aneuploidy reveals that the latter is at least four times more sensitive. These preliminary results do not support a relationship between frequency of intact fetal cells and concentration of cell-free fetal DNA. The above results imply that the concentration of fetal DNA in maternal plasma may not be dependent on circulating intact fetal cells but rather be a product of growth and cellular turnover during embryonic or fetal development.

  1. Impaired interferon-alpha production by plasmacytoid dendritic cells after cord blood transplantation in children: implication for post-transplantation toll-like receptor ligand-based immunotherapy.

    PubMed

    Charrier, Emily; Cordeiro, Paulo; Brito, Rose-Marie; Harnois, Michaël; Mezziani, Samira; Herblot, Sabine; Le Deist, Françoise; Duval, Michel

    2014-10-01

    Plasmacytoid dendritic cells (pDCs) initiate both innate and adaptive immune responses, making them attractive targets for post-transplantation immunotherapy, particularly after cord blood transplantation (CBT). Toll-like receptor (TLR) agonists are currently studied for pDC stimulation in various clinical settings. Their efficacy depends on pDC number and functionality, which are unknown after CBT. We performed a longitudinal study of pDC reconstitution in children who underwent bone marrow transplantation (BMT) and single-unit CBT. Both CBT and unrelated BMT patients received antithymocyte globulin as part of their graft-versus-host disease prophylaxis regimen. pDC blood counts were higher in CBT patients than in healthy volunteers from 2 to 9 months after transplantation, whereas they remained lower in BMT patients. We showed that cord blood progenitors gave rise in vitro to a 500-fold increase in functional pDCs over bone marrow counterparts. Upon stimulation with a TLR agonist, pDCs from both CBT and BMT recipients upregulated T cell costimulatory molecules, whereas interferon-alpha (IFN-α) production was impaired for 9 months after CBT. TLR agonist treatment is thus not expected to induce IFN-α production by pDCs after CBT, limiting its immunotherapeutic potential. Fortunately, in vitro production of large amounts of functional pDCs from cord blood progenitors paves the way for the post-transplantation adoptive transfer of pDCs. Copyright © 2014 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  2. Targeted Genome Engineering to Control VEGF Expression in Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells: Potential Implications for the Treatment of Myocardial Infarction.

    PubMed

    Cho, Hyun-Min; Kim, Pyung-Hwan; Chang, Hyun-Kyung; Shen, Yi-Ming; Bonsra, Kwaku; Kang, Byung-Jae; Yum, Soo-Young; Kim, Joo-Hyun; Lee, So-Yeong; Choi, Min-Cheol; Kim, Hyongbum Henry; Jang, Goo; Cho, Je-Yoel

    2017-03-01

    Human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) exhibit potency for the regeneration of infarcted hearts. Vascular endothelial growth factor (VEGF) is capable of inducing angiogenesis and can boost stem cell-based therapeutic effects. However, high levels of VEGF can cause abnormal blood vessel growth and hemangiomas. Thus, a controllable system to induce therapeutic levels of VEGF is required for cell therapy. We generated an inducible VEGF-secreting stem cell (VEGF/hUCB-MSC) that controls the expression of VEGF and tested the therapeutic efficacy in rat myocardial infarction (MI) model to apply functional stem cells to MI. To introduce the inducible VEGF gene cassette into a safe harbor site of the hUCB-MSC chromosome, the transcription activator-like effector nucleases system was used. After confirming the integration of the cassette into the locus, VEGF secretion in physiological concentration from VEGF/hUCB-MSCs after doxycycline (Dox) induction was proved in conditioned media. VEGF secretion was detected in mice implanted with VEGF/hUCB-MSCs grown via a cell sheet system. Vessel formation was induced in mice transplanted with Matrigel containing VEGF/hUCB-MSCs treated with Dox. Moreover, seeding of the VEGF/hUCB-MSCs onto the cardiac patch significantly improved the left ventricle ejection fraction and fractional shortening in a rat MI model upon VEGF induction. Induced VEGF/hUCB-MSC patches significantly decreased the MI size and fibrosis and increased muscle thickness, suggesting improved survival of cardiomyocytes and protection from MI damage. These results suggest that our inducible VEGF-secreting stem cell system is an effective therapeutic approach for the treatment of MI. Stem Cells Translational Medicine 2017;6:1040-1051.

  3. White blood cell counting system

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The design, fabrication, and tests of a prototype white blood cell counting system for use in the Skylab IMSS are presented. The counting system consists of a sample collection subsystem, sample dilution and fluid containment subsystem, and a cell counter. Preliminary test results show the sample collection and the dilution subsystems are functional and fulfill design goals. Results for the fluid containment subsystem show the handling bags cause counting errors due to: (1) adsorption of cells to the walls of the container, and (2) inadequate cleaning of the plastic bag material before fabrication. It was recommended that another bag material be selected.

  4. Plasma dependent reduction in red blood cell aggregation after dextran sulfate low-density lipoprotein apheresis--implications for rheological studies.

    PubMed

    Schechner, Vered; Ben-Ami, Ronen; Hershcovici, Tiberiu; Yedgar, Shaul; Beigel, Ytzhak; Shapira, Itzhak; Berliner, Shlomo; Barsthein, Gershon

    2005-10-01

    Red blood cell (RBC) aggregation is increased in familial hypercholesterolemia, and is reduced significantly after low density lipoprotein (LDL) apheresis. The purpose of the present study was to clarify whether this reduction depends on changes in plasma composition, RBC membrane properties, or both. RBC aggregation was determined in a computerized cell flow-properties analyzer, before and after LDL apheresis. We compared RBC aggregation in autologous plasma with aggregation in a plasma-free standard solution (0.5% of dextran 500 kDa) to define the separate contributions of plasma and cellular properties to the observed RBC aggregation. RBC aggregation in autologous plasma was reduced by 35.5% after LDL apheresis (P=0.01) but was not significantly affected when measured in dextran 500. This suggests that LDL apheresis attenuated RBC aggregation by altering plasma composition rather than RBC membrane properties. These results are relevant to the understanding of hemorheological changes which follow therapeutic apheresis in hypercholesterolemic patients.

  5. Long non-coding and endogenous retroviral RNA levels are associated with proinflammatory cytokine mRNA expression in peripheral blood cells: Implications for schizophrenia.

    PubMed

    Melbourne, Jennifer K; Chase, Kayla A; Feiner, Benjamin; Rosen, Cherise; Sharma, Rajiv P

    2017-09-14

    Recent research indicates that the expression of long non-coding and endogenous retroviral RNAs is coordinated with the activity of immune molecules often dysregulated in schizophrenia. We measured the expression of TMEVPG1, NRON, HERV-W env and HERV-W gag in blood cells from participants with schizophrenia and controls. We report that a) expression levels of these non-coding RNAs are correlated with proinflammatory cytokine mRNA expression in all participants, b) HERV-W transcripts are negatively correlated with atypical antipsychotic use in participants with schizophrenia, and c) that these RNAs are transcribed in response to proinflammatory stimuli in a THP-1 monocyte cell line. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Becoming a Blood Stem Cell Donor

    MedlinePlus Videos and Cool Tools

    ... Find out why Close Becoming a Blood Stem Cell Donor NCIcancertopics Loading... Unsubscribe from NCIcancertopics? Cancel Unsubscribe ... considered becoming a bone marrow or blood stem cell donor? Follow this true story of a former ...

  7. The Molecular Control of Blood Cell Development

    NASA Astrophysics Data System (ADS)

    Sachs, Leo

    1987-12-01

    The establishment of a cell culture system for the clonal development of blood cells has made it possible to identify the proteins that regulate the growth and differentiation of different blood cell lineages and to discover the molecular basis of normal and abnormal cell development in blood forming tissues. A model system with myeloid blood cells has shown that (i) normal blood cells require different proteins to induce cell multiplication (growth inducers) and cell differentiation (differentiation inducers), (ii) there is a hierarchy of growth inducers as cells become more restricted in their developmental program, and (iii) a cascade of interactions between proteins determines the correct balance between immature and mature cells in normal blood cell development. Gene cloning has shown that there is a family of different genes for these proteins. Normal protein regulators of blood cell development can control the abnormal growth of certain types of leukemic cells and suppress malignancy by incuding differentiation to mature nondividing cells. Chromosome abnormalities that give rise to malignancy in these leukemic cells can be bypassed and their effects nullified by inducing differentiation, which stops cells from multiplying. These blood cell regulatory proteins are active in culture and in the body, and they can be used clinically to correct defects in blood cell development.

  8. Kinetics and functional implications of Th1 and Th2 cytokine production following activation of peripheral blood mononuclear cells in primary culture.

    PubMed

    McHugh, S; Deighton, J; Rifkin, I; Ewan, P

    1996-06-01

    The importance of cytokine production in some disease processes is now widely recognized. To investigate temporal relationships between cytokines, we stimulated peripheral blood mononuclear cells (PBMC) in vitro using the T cell mitogen phytohemagglutinin (PHA) and various antigens chosen to induce predominantly Th1 (streptokinase: streptodornase or purified protein derivative) or Th2 (Dermatophagoides pteronyssinus, bee or wasp venom: allergens in sensitive subjects) responses. Cytokine production was measured by sensitive bioassays or enzyme-linked immunosorbent assays. Of the 30 subjects studied, 10 were normal and 20 individuals were allergic to either D. pteronyssinus (n = 10) or bee venom (n = 10) (examined before specific allergen immunotherapy). We examined the temporal profiles of a panel of cytokines produced in primary culture. In PHA-driven cultures, cytokines were found to be sequentially produced in the order interleukin (IL)-2, IL-4, IL-5, IL-3, interferon (IFN)-gamma, IL-10, IL-6, IL-12 and tumor necrosis factor (TNF)-alpha. The response to allergen in allergic patients was predominantly Th2 in nature, with the production of IL-4, IL-5, IL-6 and IL-10, but little or no IFN-gamma. IL-2, IL-3, TNF-alpha and IL-12 were also produced in low amounts. The response of both atopic and normal subjects to recall bacterial antigens was predominantly Th1, with high levels of IFN-gamma, IL-2 and TNF-alpha. The relevance of the order, amount and speed of production, characteristic kinetics (production, consumption, homeostatic regulation) and the cell source of the cytokines are discussed.

  9. Prolonged storage of packed red blood cells for blood transfusion.

    PubMed

    Martí-Carvajal, Arturo J; Simancas-Racines, Daniel; Peña-González, Barbra S

    2015-07-14

    A blood transfusion is an acute intervention, used to address life- and health-threatening conditions on a short-term basis. Packed red blood cells are most often used for blood transfusion. Sometimes blood is transfused after prolonged storage but there is continuing debate as to whether transfusion of 'older' blood is as beneficial as transfusion of 'fresher' blood. To assess the clinical benefits and harms of prolonged storage of packed red blood cells, in comparison with fresh, on recipients of blood transfusion. We ran the search on 1st May 2014. We searched the Cochrane Injuries Group Specialized Register, Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library), MEDLINE (OvidSP), Embase (OvidSP), CINAHL (EBSCO Host) and two other databases. We also searched clinical trials registers and screened reference lists of the retrieved publications and reviews. We updated this search in June 2015 but these results have not yet been incorporated. Randomised clinical trials including participants assessed as requiring red blood cell transfusion were eligible for inclusion. Prolonged storage was defined as red blood cells stored for ≥ 21 days in a blood bank. We did not apply limits regarding the duration of follow-up, or country where the study took place. We excluded trials where patients received a combination of short- and long-stored blood products, and also trials without a clear definition of prolonged storage. We independently performed study selection, risk of bias assessment and data extraction by at least two review authors. The major outcomes were death from any cause, transfusion-related acute lung injury, and adverse events. We estimated relative risk for dichotomous outcomes. We measured statistical heterogeneity using I(2). We used a random-effects model to synthesise the findings. We identified three randomised clinical trials, involving a total of 120 participants, comparing packed red blood cells with ≥ 21 days storage

  10. Myeloid cell origins, differentiation, and clinical implications

    PubMed Central

    Weiskopf, Kipp; Schnorr, Peter J.; Pang, Wendy W.; Chao, Mark P.; Chhabra, Akanksha; Seita, Jun; Feng, Mingye; Weissman, Irving L.

    2016-01-01

    The hematopoietic stem cell (HSC) is a multipotent stem cell that resides in the bone marrow and has the ability to form all of the cells of the blood and immune system. Since its first purification in 1988, additional studies have refined the phenotype and functionality of HSCs and characterized all of their downstream progeny. The hematopoietic lineage is divided into two main branches: the myeloid and lymphoid arms. The myeloid arm is characterized by the Common Myeloid Progenitor and all of its resulting cell types. The stages of hematopoiesis have been defined in both mice and humans. During embryological development, the earliest hematopoiesis takes place in yolk sac blood islands then migrates to the fetal liver and hematopoietic organs. Some adult myeloid populations develop directly from yolk sac progenitors without apparent bone marrow intermediates, such as tissue resident macrophages. Hematopoiesis also changes over time, with a bias of the dominating HSCs towards myeloid development as animals age. Defects in myelopoiesis contribute to many hematologic disorders, and some of these can be overcome with therapies that target the aberrant stage of development. Furthermore, insights into myeloid development have informed us of mechanisms of programmed cell removal. The CD47/SIRPα axis, a myeloid-specific immune checkpoint, limits macrophage removal of HSCs but can be exploited by hematologic and solid malignancies. Therapeutics targeting CD47 represent a new strategy for treating cancer. Overall, an understanding of hematopoiesis and myeloid cell development has implications for regenerative medicine, hematopoietic cell transplantation, malignancy, and many other diseases. PMID:27763252

  11. Uptake of carnitine by red blood cells

    SciTech Connect

    Campa, M.; Borum, P.

    1986-05-01

    A significant amount of blood carnitine (70% of cord blood and 40% of blood from healthy adults) is partitioned into the red blood cell compartment of whole blood. Data indicate that the plasma compartment and the red blood cell compartment of whole blood represent different metabolic pools of carnitine. There are no data to indicate that red blood cells synthesize carnitine, but our understanding of the uptake of carnitine by red blood cells is negligible. Red blood cells were obtained from healthy adults, washed twice with normal saline, and used for uptake experiments. When the cells were incubated at 37/sup 0/C in the presence of /sup 14/C-carnitine, radioactivity was found both in the soluble cytosolic and membrane fractions of the cells following lysis. The uptake was dependent upon the time of incubation, temperature of incubation, and carnitine concentration in the incubation medium. Washed red blood cell membranes incubated with /sup 14/C-carnitine showed specific binding of radioactivity. These data are consistent with the hypothesis that red blood cells have an uptake mechanism for L-carnitine.

  12. Red blood cell storage and cell morphology.

    PubMed

    Blasi, B; D'Alessandro, A; Ramundo, N; Zolla, L

    2012-04-01

    In this study, we performed weekly assessment of morphology-related parameters through monitoring of CPD-SAGM leuco-filtered erythrocyte concentrates from blood withdrawal until the 42nd day of storage. Liquid storage of red blood cells (RBCs) delivers a blood-derived therapeutic, which is safe, available, effective and affordable for most patients who need transfusion therapy in developed countries. However, a growing body of accumulating controversial evidences, from either biochemical or retrospective clinical studies, prompted safety concerns about longer stored RBCs. Statistical image analysis through scanning electron microscope was coupled to osmotic fragility and erythrocyte sedimentation rate. We could observe that by day 21 more than 50% of RBCs displayed non-discocyte phenotypes. This observation was related to an increase in osmotic fragility, which was totally overlapped in day 0 controls and day 7 RBCs while only slightly augmented in day 14 samples. Cation dysregulation (pH internal/external alteration and potassium) might both reflect and trigger a negative feedback loop with metabolic fluxes and membrane cation pumps. Morphology parameters suggest that significant alterations to RBC morphology over storage duration occur soon after the 14th day of storage, as to become significant enough within the 21st day. © 2012 The Authors. Transfusion Medicine © 2012 British Blood Transfusion Society.

  13. Mechanisms linking red blood cell disorders and cardiovascular diseases.

    PubMed

    Mozos, Ioana

    2015-01-01

    The present paper aims to review the main pathophysiological links between red blood cell disorders and cardiovascular diseases, provides a brief description of the latest studies in this area, and considers implications for clinical practice and therapy. Anemia is associated with a special risk in proatherosclerotic conditions and heart disease and became a new therapeutic target. Guidelines must be updated for the management of patients with red blood cell disorders and cardiovascular diseases, and targets for hemoglobin level should be established. Risk scores in several cardiovascular diseases should include red blood cell count and RDW. Complete blood count and hemorheological parameters represent useful, inexpensive, widely available tools for the management and prognosis of patients with coronary heart disease, heart failure, hypertension, arrhythmias, and stroke. Hypoxia and iron accumulation cause the most important cardiovascular effects of sickle cell disease and thalassemia. Patients with congenital chronic hemolytic anemia undergoing splenectomy should be monitored, considering thromboembolic and cardiovascular risk.

  14. Mechanisms Linking Red Blood Cell Disorders and Cardiovascular Diseases

    PubMed Central

    2015-01-01

    The present paper aims to review the main pathophysiological links between red blood cell disorders and cardiovascular diseases, provides a brief description of the latest studies in this area, and considers implications for clinical practice and therapy. Anemia is associated with a special risk in proatherosclerotic conditions and heart disease and became a new therapeutic target. Guidelines must be updated for the management of patients with red blood cell disorders and cardiovascular diseases, and targets for hemoglobin level should be established. Risk scores in several cardiovascular diseases should include red blood cell count and RDW. Complete blood count and hemorheological parameters represent useful, inexpensive, widely available tools for the management and prognosis of patients with coronary heart disease, heart failure, hypertension, arrhythmias, and stroke. Hypoxia and iron accumulation cause the most important cardiovascular effects of sickle cell disease and thalassemia. Patients with congenital chronic hemolytic anemia undergoing splenectomy should be monitored, considering thromboembolic and cardiovascular risk. PMID:25710019

  15. Trapping cells in paper for white blood cell count.

    PubMed

    Zhang, Yi; Bai, Jianhao; Wu, Hong; Ying, Jackie Y

    2015-07-15

    White blood cell count is an important indicator of each individual's health condition. An abnormal white blood cell count usually results from an infection, cancer, or other conditions that trigger systemic inflammation responses. White blood cell count also provides predictive information on the incidence of cardiovascular diseases and Type 2 diabetes. Therefore, monitoring white blood cell count on a regular basis can potentially help individuals to take preventive measures and improve healthcare outcomes. Currently, white blood cell count is primarily conducted in centralized laboratories, and it requires specialized equipment and dedicated personnel to perform the test and interpret the results. So far there has been no rapid test that allows white blood cell count in low-resource settings. In this study, we have demonstrated a vertical flow platform that quantifies white blood cells by trapping them in the paper. White blood cells were tagged with gold nanoparticles, and flowed through the paper via a small orifice. The white blood cell count was determined by measuring the colorimetric intensity of gold nanoparticles on the surface of white blood cells that were trapped in the paper mesh. Using this platform, we were able to quantify white blood cells in 15 μL of blood, and visually differentiate the abnormal count of white blood cells from the normal count. The proposed platform enabled rapid white blood cell count in low resource settings with a small sample volume requirement. Its low-cost, instrument-free operations would be attractive for point-of-care applications.

  16. Red blood cell vesiculation in hereditary hemolytic anemia

    PubMed Central

    Alaarg, Amr; Schiffelers, Raymond M.; van Solinge, Wouter W.; van Wijk, Richard

    2013-01-01

    Hereditary hemolytic anemia encompasses a heterogeneous group of anemias characterized by decreased red blood cell survival because of inherited membrane, enzyme, or hemoglobin disorders. Affected red blood cells are more fragile, less deformable, and more susceptible to shear stress and oxidative damage, and show increased vesiculation. Red blood cells, as essentially all cells, constitutively release phospholipid extracellular vesicles in vivo and in vitro in a process known as vesiculation. These extracellular vesicles comprise a heterogeneous group of vesicles of different sizes and intracellular origins. They are described in literature as exosomes if they originate from multi-vesicular bodies, or as microvesicles when formed by a one-step budding process directly from the plasma membrane. Extracellular vesicles contain a multitude of bioactive molecules that are implicated in intercellular communication and in different biological and pathophysiological processes. Mature red blood cells release in principle only microvesicles. In hereditary hemolytic anemias, the underlying molecular defect affects and determines red blood cell vesiculation, resulting in shedding microvesicles of different compositions and concentrations. Despite extensive research into red blood cell biochemistry and physiology, little is known about red cell deformability and vesiculation in hereditary hemolytic anemias, and the associated pathophysiological role is incompletely assessed. In this review, we discuss recent progress in understanding extracellular vesicles biology, with focus on red blood cell vesiculation. Also, we review recent scientific findings on the molecular defects of hereditary hemolytic anemias, and their correlation with red blood cell deformability and vesiculation. Integrating bio-analytical findings on abnormalities of red blood cells and their microvesicles will be critical for a better understanding of the pathophysiology of hereditary hemolytic anemias. PMID

  17. Red blood cell vesiculation in hereditary hemolytic anemia.

    PubMed

    Alaarg, Amr; Schiffelers, Raymond M; van Solinge, Wouter W; van Wijk, Richard

    2013-12-13

    Hereditary hemolytic anemia encompasses a heterogeneous group of anemias characterized by decreased red blood cell survival because of inherited membrane, enzyme, or hemoglobin disorders. Affected red blood cells are more fragile, less deformable, and more susceptible to shear stress and oxidative damage, and show increased vesiculation. Red blood cells, as essentially all cells, constitutively release phospholipid extracellular vesicles in vivo and in vitro in a process known as vesiculation. These extracellular vesicles comprise a heterogeneous group of vesicles of different sizes and intracellular origins. They are described in literature as exosomes if they originate from multi-vesicular bodies, or as microvesicles when formed by a one-step budding process directly from the plasma membrane. Extracellular vesicles contain a multitude of bioactive molecules that are implicated in intercellular communication and in different biological and pathophysiological processes. Mature red blood cells release in principle only microvesicles. In hereditary hemolytic anemias, the underlying molecular defect affects and determines red blood cell vesiculation, resulting in shedding microvesicles of different compositions and concentrations. Despite extensive research into red blood cell biochemistry and physiology, little is known about red cell deformability and vesiculation in hereditary hemolytic anemias, and the associated pathophysiological role is incompletely assessed. In this review, we discuss recent progress in understanding extracellular vesicles biology, with focus on red blood cell vesiculation. Also, we review recent scientific findings on the molecular defects of hereditary hemolytic anemias, and their correlation with red blood cell deformability and vesiculation. Integrating bio-analytical findings on abnormalities of red blood cells and their microvesicles will be critical for a better understanding of the pathophysiology of hereditary hemolytic anemias.

  18. 21 CFR 640.10 - Red Blood Cells.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 7 2011-04-01 2010-04-01 true Red Blood Cells. 640.10 Section 640.10 Food and... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.10 Red Blood Cells. The proper name of this product shall be Red Blood Cells. The product is defined as red blood cells...

  19. 21 CFR 640.10 - Red Blood Cells.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Red Blood Cells. 640.10 Section 640.10 Food and... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.10 Red Blood Cells. The proper name of this product shall be Red Blood Cells. The product is defined as red blood cells...

  20. 21 CFR 640.10 - Red Blood Cells.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 7 2014-04-01 2014-04-01 false Red Blood Cells. 640.10 Section 640.10 Food and... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.10 Red Blood Cells. The proper name of this product shall be Red Blood Cells. The product is defined as red blood cells...

  1. 21 CFR 640.10 - Red Blood Cells.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 7 2012-04-01 2012-04-01 false Red Blood Cells. 640.10 Section 640.10 Food and... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.10 Red Blood Cells. The proper name of this product shall be Red Blood Cells. The product is defined as red blood cells...

  2. 21 CFR 640.10 - Red Blood Cells.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 7 2013-04-01 2013-04-01 false Red Blood Cells. 640.10 Section 640.10 Food and... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Red Blood Cells § 640.10 Red Blood Cells. The proper name of this product shall be Red Blood Cells. The product is defined as red blood cells...

  3. Blood Cell Interactions and Segregation in Flow

    PubMed Central

    Munn, Lance L.; Dupin, Michael M.

    2009-01-01

    For more than a century, pioneering researchers have been using novel experimental and computational approaches to probe the mysteries of blood flow. Thanks to their efforts, we know that blood cells generally prefer to migrate to the axis of flow, that red and white cells segregate in flow, and that cell deformability and their tendency to reversibly aggregate contribute to the non-Newtonian nature of this unique fluid. All of these properties have beneficial physiological consequences, allowing blood to perform a variety of critical functions. Our current understanding of these unusual flow properties of blood have been made possible by the ingenuity and diligence of a number of researchers, including Harry Goldsmith, who developed novel technologies to visualize and quantify the flow of blood at the level of individual cells. Here we summarize efforts in our lab to continue this tradition and to further our understanding of how blood cells interact with each other and with the blood vessel wall. PMID:18188702

  4. Squeezing red blood cells on an optical waveguide to monitor cell deformability during blood storage.

    PubMed

    Ahluwalia, Balpreet Singh; McCourt, Peter; Oteiza, Ana; Wilkinson, James S; Huser, Thomas R; Hellesø, Olav Gaute

    2015-01-07

    Red blood cells squeeze through micro-capillaries as part of blood circulation in the body. The deformability of red blood cells is thus critical for blood circulation. In this work, we report a method to optically squeeze red blood cells using the evanescent field present on top of a planar waveguide chip. The optical forces from a narrow waveguide are used to squeeze red blood cells to a size comparable to the waveguide width. Optical forces and pressure distributions on the cells are numerically computed to explain the squeezing process. The proposed technique is used to quantify the loss of blood deformability that occurs during blood storage lesion. Squeezing red blood cells using waveguides is a sensitive technique and works simultaneously on several cells, making the method suitable for monitoring stored blood.

  5. Blood

    MedlinePlus

    ... The liquid part, called plasma, is made of water, salts, and protein. Over half of your blood is plasma. The solid part of your blood contains red blood cells, white blood cells, and platelets. Red ...

  6. Measuring sickle cell morphology during blood flow.

    PubMed

    Kviatkovsky, Inna; Zeidan, Adel; Yeheskely-Hayon, Daniella; Shabad, Eveline L; Dann, Eldad J; Yelin, Dvir

    2017-03-01

    During a sickle cell crisis in sickle cell anemia patients, deoxygenated red blood cells may change their mechanical properties and block small blood vessels, causing pain, local tissue damage, and possibly organ failure. Measuring the structural and morphological changes in sickle cells is important for understanding the factors contributing to vessel blockage and for developing an effective treatment. In this work, we image blood cells from sickle cell anemia patients using spectrally encoded flow cytometry, and analyze the interference patterns between reflections from the cell membranes. Using a numerical simulation for calculating the interference pattern obtained from a model of a red blood cell, we propose an analytical expression for the three-dimensional shape of characteristic sickle cells and compare our results to a previously suggested model. Our imaging approach offers new means for analyzing the morphology of sickle cells, and could be useful for studying their unique physiological and biomechanical properties.

  7. Racial differences in hypertension: implications for high blood pressure management.

    PubMed

    Lackland, Daniel T

    2014-08-01

    The racial disparity in hypertension and hypertension-related outcomes has been recognized for decades with African Americans with greater risks than Caucasians. Blood pressure levels have consistently been higher for African Americans with an earlier onset of hypertension. Although awareness and treatment levels of high blood pressure have been similar, racial differences in control rates are evident. The higher blood pressure levels for African Americans are associated with higher rates of stroke, end-stage renal disease and congestive heart failure. The reasons for the racial disparities in elevated blood pressure and hypertension-related outcomes risk remain unclear. However, the implications of the disparities of hypertension for prevention and clinical management are substantial, identifying African American men and women with excel hypertension risk and warranting interventions focused on these differences. In addition, focused research to identify the factors attributed to these disparities in risk burden is an essential need to address the evidence gaps.

  8. Biomechanics and biorheology of red blood cells in sickle cell anemia

    PubMed Central

    Li, Xuejin; Dao, Ming; Lykotrafitis, George; Karniadakis, George Em

    2017-01-01

    Sickle cell anemia (SCA) is an inherited blood disorder that causes painful crises due to vaso-occlusion of small blood vessels. The primary cause of the clinical phenotype of SCA is the intracellular polymerization of sickle hemoglobin resulting in sickling of red blood cells (RBCs) in deoxygenated conditions. In this review, we discuss the biomechanical and biorheological characteristics of sickle RBCs and sickle blood as well as their implications toward a better understanding of the pathophysiology and pathogenesis of SCA. Additionally, we highlight the adhesive heterogeneity of RBCs in SCA and their specific contribution to vaso-occlusive crisis. PMID:27876368

  9. Biomechanics and biorheology of red blood cells in sickle cell anemia.

    PubMed

    Li, Xuejin; Dao, Ming; Lykotrafitis, George; Karniadakis, George Em

    2017-01-04

    Sickle cell anemia (SCA) is an inherited blood disorder that causes painful crises due to vaso-occlusion of small blood vessels. The primary cause of the clinical phenotype of SCA is the intracellular polymerization of sickle hemoglobin resulting in sickling of red blood cells (RBCs) in deoxygenated conditions. In this review, we discuss the biomechanical and biorheological characteristics of sickle RBCs and sickle blood as well as their implications toward a better understanding of the pathophysiology and pathogenesis of SCA. Additionally, we highlight the adhesive heterogeneity of RBCs in SCA and their specific contribution to vaso-occlusive crisis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Microfluidic Blood Cell Preparation: Now and Beyond

    PubMed Central

    Yu, Zeta Tak For; Yong, Koh Meng Aw; Fu, Jianping

    2014-01-01

    Blood plays an important role in homeostatic regulation with each of its cellular components having important therapeutic and diagnostic uses. Therefore, separation and sorting of blood cells has been of a great interest to clinicians and researchers. However, while conventional methods of processing blood have been successful in generating relatively pure fractions, they are time consuming, labor intensive, and are not optimal for processing small volume blood samples. In recent years, microfluidics has garnered great interest from clinicians and researchers as a powerful technology for separating blood into different cell fractions. As microfluidics involves fluid manipulation at the microscale level, it has the potential for achieving high-resolution separation and sorting of blood cells down to a single-cell level, with an added benefit of integrating physical and biological methods for blood cell separation and analysis on the same single chip platform. This paper will first review the conventional methods of processing and sorting blood cells, followed by a discussion on how microfluidics is emerging as an efficient tool to rapidly change the field of blood cell sorting for blood-based therapeutic and diagnostic applications. PMID:24515899

  11. 21 CFR 864.6160 - Manual blood cell counting device.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Manual blood cell counting device. 864.6160... blood cell counting device. (a) Identification. A manual blood cell counting device is a device used to count red blood cells, white blood cells, or blood platelets. (b) Classification. Class I (general...

  12. 21 CFR 864.6160 - Manual blood cell counting device.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Manual blood cell counting device. 864.6160... blood cell counting device. (a) Identification. A manual blood cell counting device is a device used to count red blood cells, white blood cells, or blood platelets. (b) Classification. Class I (general...

  13. 21 CFR 864.6160 - Manual blood cell counting device.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Manual blood cell counting device. 864.6160... blood cell counting device. (a) Identification. A manual blood cell counting device is a device used to count red blood cells, white blood cells, or blood platelets. (b) Classification. Class I (general...

  14. 21 CFR 864.6160 - Manual blood cell counting device.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Manual blood cell counting device. 864.6160... blood cell counting device. (a) Identification. A manual blood cell counting device is a device used to count red blood cells, white blood cells, or blood platelets. (b) Classification. Class I (general...

  15. Blood

    MedlinePlus

    ... that die or are lost from the body. White Blood Cells White blood cells (WBCs, and also ... of severe pain. previous continue Diseases of the White Blood Cells Neutropenia (pronounced: new-truh-PEE-nee- ...

  16. [Immunological blood transfusion safety and selection of red blood cells issued from hospital blood banks].

    PubMed

    Py, J-Y

    2010-12-01

    Allogeneic red blood cells transfusion is always an immunological challenge and the choice of the blood products is crucial for the patient safety. But this choice may be hampered by the quality or the quantity of the available supply. In the end, the lack of transfusion may be more harmful than transfusion. The balance between patients' needs and blood centres supplying is always delicate. The conditions are not the same for all blood groups. Things are easier for the KEL1 phenotype, where the supply must ensure only 92.5% of KEL: -1 red blood cells instead of the 91% expected. More complicated is the situation for group O red blood cells with 47 versus 43%. But the major problem concerns RH: -1 red blood cells, for which the needs reach 20.1 versus 15%. These challenges require a lot of efforts from blood centres staffs to influence blood donors' recruitment and appointments. A justified and carefully selected blood products issuing may be of great help, especially for group O RH: -1 red blood cells. Therefore, hospital blood banks must have ad hoc procedures and a trained staff to put them into practice.

  17. Isolation of rare cancer cells from blood cells using dielectrophoresis.

    PubMed

    Salmanzadeh, Alireza; Sano, Michael B; Shafiee, Hadi; Stremler, Mark A; Davalos, Rafael V

    2012-01-01

    In this study, we investigate the application of contactless dielectrophoresis (cDEP) for isolating cancer cells from blood cells. Devices with throughput of 0.2 mL/hr (equivalent to sorting 3×10(6) cells per minute) were used to trap breast cancer cells while allowing blood cells through. We have shown that this technique is able to isolate cancer cells in concentration as low as 1 cancer cell per 10(6) hematologic cells (equivalent to 1000 cancer cells in 1 mL of blood). We achieved 96% trapping of the cancer cells at 600 kHz and 300 V(RMS).

  18. Blood cell characterization by light scattering

    NASA Astrophysics Data System (ADS)

    Magnin, Olivier

    2004-09-01

    In this paper we are going to introduce optical methods for blood cell characterization performed by standard hematology analyzers. As a consequence, we are going to focus on methods that are, or will be, compatible with an average cost, commercial, blood cell counter.

  19. Activation of blood coagulation in cancer: implications for tumour progression

    PubMed Central

    Lima, Luize G.; Monteiro, Robson Q.

    2013-01-01

    Several studies have suggested a role for blood coagulation proteins in tumour progression. Herein, we discuss (1) the activation of the blood clotting cascade in the tumour microenvironment and its impact on primary tumour growth; (2) the intravascular activation of blood coagulation and its impact on tumour metastasis and cancer-associated thrombosis; and (3) antitumour therapies that target blood-coagulation-associated proteins. Expression levels of the clotting initiator protein TF (tissue factor) have been correlated with tumour cell aggressiveness. Simultaneous TF expression and PS (phosphatidylserine) exposure by tumour cells promote the extravascular activation of blood coagulation. The generation of blood coagulation enzymes in the tumour microenvironment may trigger the activation of PARs (protease-activated receptors). In particular, PAR1 and PAR2 have been associated with many aspects of tumour biology. The procoagulant activity of circulating tumour cells favours metastasis, whereas the release of TF-bearing MVs (microvesicles) into the circulation has been correlated with cancer-associated thrombosis. Given the role of coagulation proteins in tumour progression, it has been proposed that they could be targets for the development of new antitumour therapies. PMID:23889169

  20. Activation of blood coagulation in cancer: implications for tumour progression.

    PubMed

    Lima, Luize G; Monteiro, Robson Q

    2013-09-04

    Several studies have suggested a role for blood coagulation proteins in tumour progression. Herein, we discuss (1) the activation of the blood clotting cascade in the tumour microenvironment and its impact on primary tumour growth; (2) the intravascular activation of blood coagulation and its impact on tumour metastasis and cancer-associated thrombosis; and (3) antitumour therapies that target blood-coagulation-associated proteins. Expression levels of the clotting initiator protein TF (tissue factor) have been correlated with tumour cell aggressiveness. Simultaneous TF expression and PS (phosphatidylserine) exposure by tumour cells promote the extravascular activation of blood coagulation. The generation of blood coagulation enzymes in the tumour microenvironment may trigger the activation of PARs (protease-activated receptors). In particular, PAR1 and PAR2 have been associated with many aspects of tumour biology. The procoagulant activity of circulating tumour cells favours metastasis, whereas the release of TF-bearing MVs (microvesicles) into the circulation has been correlated with cancer-associated thrombosis. Given the role of coagulation proteins in tumour progression, it has been proposed that they could be targets for the development of new antitumour therapies.

  1. Peripheral Blood Stem Cell Transplant Related Plasmodium falciparum Infection in a Patient with Sickle Cell Disease

    PubMed Central

    Mejia, Rojelio; Booth, Garrett S.; Fedorko, Daniel P.; Hsieh, Matthew M.; Khuu, Hanh M.; Klein, Harvey G.; Mu, Jianbing; Fahle, Gary; Nutman, Thomas B.; Su, Xin-Zhuan; Williams, Esther C.; Flegel, Willy A.; Klion, Amy

    2012-01-01

    Background Although transmission of Plasmodium falciparum (Pf) infection during red blood cell transfusion from an infected donor has been well documented, malaria parasites are not known to infect hematopoietic stem cells. We report a case of Pf infection in a patient 11 days after peripheral blood stem cell transplant for sickle cell disease. Study Design and Methods Malaria parasites were detected in thick blood smears by Giemsa staining. Pf HRP2 antigen was measured by ELISA on whole blood and plasma. Pf DNA was detected in whole blood and stem cell retention samples by real-time PCR using Pf species–specific primers and probes. Genotyping of 8 Pf microsatellites was performed on genomic DNA extracted from whole blood. Results Pf was not detected by molecular, serologic or parasitologic means in samples from the recipient until day 11 post-transplant, coincident with the onset of symptoms. In contrast, Pf antigen was retrospectively detected in stored plasma collected 3 months prior to transplant from the asymptomatic donor. Pf DNA was detected in whole blood from both the donor and recipient post-transplant, and genotyping confirmed shared markers between donor and recipient Pf strains. Look back analysis of red blood cell donors was negative for Pf infection. Conclusions These findings are consistent with transmission by the stem cell product and have profound implications with respect to the screening of potential stem cell donors and recipients from malaria-endemic regions. PMID:22536941

  2. Red blood cell decreases of microgravity

    NASA Technical Reports Server (NTRS)

    Johnson, P. C.

    1985-01-01

    Postflight decreases in red blood cell mass (RBCM) have regularly been recorded after exposure to microgravity. These 5-25 percent decreases do not relate to the mission duration, workload, caloric intake or to the type of spacecraft used. The decrease is accompanied by normal red cell survivals, increased ferritin levels, normal radioactive iron studies, and increases in mean red blood cell volume. Comparable decreases in red blood cell mass are not found after bed rest, a commonly used simulation of the microgravity state. Inhibited bone marrow erythropoiesis has not been proven to date, although reticulocyte numbers in the peripheral circulation are decreased about 50 percent. To date, the cause of the microgravity induced decreases in RBCM is unknown. Increased splenic trapping of circulating red blood cells seem the most logical way to explain the results obtained.

  3. Human spleen and red blood cells

    NASA Astrophysics Data System (ADS)

    Pivkin, Igor; Peng, Zhangli; Karniadakis, George; Buffet, Pierre; Dao, Ming

    2016-11-01

    Spleen plays multiple roles in the human body. Among them is removal of old and altered red blood cells (RBCs), which is done by filtering cells through the endothelial slits, small micron-sized openings. There is currently no experimental technique available that allows us to observe RBC passage through the slits. It was previously noticed that people without a spleen have less deformable red blood cells, indicating that the spleen may play a role in defining the size and shape of red blood cells. We used detailed RBC model implemented within the Dissipative Particle Dynamics (DPD) simulation framework to study the filter function of the spleen. Our results demonstrate that spleen indeed plays major role in defining the size and shape of the healthy human red blood cells.

  4. Red blood cell decreases of microgravity

    NASA Technical Reports Server (NTRS)

    Johnson, P. C.

    1985-01-01

    Postflight decreases in red blood cell mass (RBCM) have regularly been recorded after exposure to microgravity. These 5-25 percent decreases do not relate to the mission duration, workload, caloric intake or to the type of spacecraft used. The decrease is accompanied by normal red cell survivals, increased ferritin levels, normal radioactive iron studies, and increases in mean red blood cell volume. Comparable decreases in red blood cell mass are not found after bed rest, a commonly used simulation of the microgravity state. Inhibited bone marrow erythropoiesis has not been proven to date, although reticulocyte numbers in the peripheral circulation are decreased about 50 percent. To date, the cause of the microgravity induced decreases in RBCM is unknown. Increased splenic trapping of circulating red blood cells seem the most logical way to explain the results obtained.

  5. Digital image analysis of blood cells.

    PubMed

    Da Costa, Lydie

    2015-03-01

    Rapid and accurate counts of red blood cells (RBCs), nucleated RBCs, platelets, and white blood cells (WBCs) (total and differential WBCs) are important requirements for a hematology laboratory. The detection of abnormal blood cell populations and the recognition of pathologic distributions of leukocytes are also of clinical importance. Manual microscopy counts are still required when a sample is flagged by the hematology analyzer and are still the reference method for WBC differential counts. Automated microscopy analyzers can provide accurate WBC differential counts, which may replace manual microscopy, but should not replace the eye of the cytologist. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Sickle red blood cells accumulate in tumor.

    PubMed

    Brown, S L; Ewing, J R; Nagaraja, T N; Swerdlow, P S; Cao, Y; Fenstermacher, J D; Kim, J H

    2003-12-01

    The preferential accumulation of sickle blood cells in tumor vasculature is demonstrated noninvasively using MRI and sickle red blood cells loaded with Gd-DTPA and invasively by two other techniques. The distribution of red blood cells in rat brain tumors relative to normal brains were measured using three separate techniques: MRI of Gd-DTPA loaded cells, fluorescent microscopy detection of Oregon Green 488 fluorescence conjugated to a streptavidin-biotin complex that binds to red blood cell surface proteins, and autoradiography using a technetium (99m)Tc-labeling kit. Labeled red cells were infused intravenously in rats with brain tumors. Sickle cells preferentially accumulated in tumor relative to normal brain, with highest concentrations near the tumor / normal tissue boundary, whereas control normal red cells did not preferentially aggregate at the tumor periphery. This demonstrates the potential of sickle red blood cells to accumulate in the abnormal tumor vessel network, and the ability to detect their aggregation noninvasively and at high spatial resolution using MRI. The application of the noninvasive measurement of sickle cells for imaging tumor neovasculature, or as a delivery tool for therapy, requires further study. Copyright 2003 Wiley-Liss, Inc.

  7. Characterization of red blood cell deformability change during blood storage.

    PubMed

    Zheng, Yi; Chen, Jun; Cui, Tony; Shehata, Nadine; Wang, Chen; Sun, Yu

    2014-02-07

    Stored red blood cells (RBCs) show progressive deformability changes during blood banking/storage. Their deformability changes over an 8 weeks' storage period were measured using a microfluidic device. Hydrodynamic focusing controls the orientation and position of individual RBCs within the microchannel. High-speed imaging (5000 frames s(-1)) captures the dynamic deformation behavior of the cells, and together with automated image analysis, enables the characterization of over 1000 RBCs within 3 minutes. Multiple parameters including deformation index (DI), time constant (shape recovery rate), and RBC circularity were quantified. Compared to previous studies on stored RBC deformability, our results include a significantly higher number of cells (>1000 cells per sample vs. a few to tens of cells per sample) and, for the first time, reveal deformation changes of stored RBCs when traveling through human-capillary-like microchannels. Contrary to existing knowledge, our results demonstrate that the deformation index of RBCs under folding does not change significantly over blood storage. However, significant differences exist in time constants and circularity distribution widths, which can be used to quantify stored RBC quality or age.

  8. Quantifying cerebral blood flow: regional regulation with global implications.

    PubMed

    Small, Scott A

    2004-10-01

    In 1948, Seymour S. Kety and Carl F. Schmidt published back-to-back papers in the JCI that are widely acknowledged as landmarks. Upon publication, the studies resolved a century-old debate, irrefutably demonstrating that cerebral blood flow is regionally regulated. The reported findings turned out to be so powerful in their implications that they provided the inspirational spark that illuminated a brand-new field: functional brain imaging. Thus these papers are landmarks of the rarest kind, not only ending a controversy, but also giving birth to one of the most exciting fields within modern day neuroscience.

  9. Impact of Radiation on Blood Cell Deformability

    DTIC Science & Technology

    2008-09-19

    Cell Separation," (2007). John A. Davis, "Microfluidic Separation of Blood Components through Deterministic Lateral Displacement," (2008...literature. For more details and references see Chapter 6 of the Ph.D. thesis of John A. Davis, "Microfluidic Separation of Blood Components through

  10. Blood-Forming Stem Cell Transplants

    MedlinePlus

    ... Health Professionals Questions to Ask about Your Treatment Research Blood-Forming Stem Cell Transplants On This Page What are bone marrow ... are evaluating BMT and PBSCT in clinical trials (research studies) for the treatment ... are the donor’s stem cells matched to the patient’s stem cells in allogeneic ...

  11. Low white blood cell count and cancer

    MedlinePlus

    Neutropenia and cancer; Absolute neutrophil count and cancer; ANC and cancer ... A person with cancer can get a low white blood cell count from the cancer or from treatment for the cancer. Cancer may ...

  12. Haemoglobin variants among voluntary blood donors in Jos, Nigeria: the implications on blood transfusion.

    PubMed

    Damulak, O D; Bolorunduro, S A; Egesie, J O; Yakubu, K; Godit, P; Smith, O A

    2013-01-01

    The normal haemoglobin is an efficient transporter of oxygen to the tissues and carbondioxide from tissues to the lungs for elimination. Various abnormal haemoglobin variants including, the sickle cell diseases, have been described with varying sickling tendencies. This study aimed to determine the haemoglobin variants among voluntary blood donors in Jos. Records of the age, sex, Haemoglobin level, and the haemoglobin genotype of all voluntary blood donors who donated blood at the National Blood Transfusion Service Centre, Jos, Nigeria between January 2011 and April 2012; and their haemoglobin levels and protein electrophoresis determined, were reviewed. A total of 937 blood donors, 658 (70.23%) males and 279 (29.79%) females, mean age 32.4 years, donated blood voluntarily, their haemoglobin electrophoretic patterns determined by alkaline cellulose acetate electrophoresis. Donor blood haemoglobin levels were determined by automation. Haemoglobin protein electrophoretic patterns identified among our donors were 77.70% AA, 21.88% AS, 0.22% SC, 0.11% AC and 0.11% SS. Mean haemoglobin levels of the donors according to their haemoglobin proteins electrophoretic patterns were, 150.4 +/- 12.5 gms/l for AA, 151.9 +/- 13.8 gms/l for AS and 131.1 +/- 5.0 gms/l for haemoglobin SC. Determination of haemoglobin protein electrophoretic patterns of blood unit for transfusion could enhance selective blood issuing based on recipient's haemoglobin type.

  13. Freeze-Dried Human Red Blood Cells.

    DTIC Science & Technology

    1992-07-15

    instructed not to consume any alcohol -containing beverage during the period from seven days prior to phlebotomy to the completion of the follow-up...over the heart, spleen and liver at 4 hours and 24 hours post-infusion to determine the organ distribution of the radiolabeled reconstituted red blood...cells. 4. External probe counts taken over the heart, liver and spleen to determine the distribution of the lyophilized red blood cells at 4 hours and

  14. Anesthetics and red blood cell rheology

    NASA Astrophysics Data System (ADS)

    Aydogan, Burcu; Aydogan, Sami

    2014-05-01

    There are many conditions where it is useful for anesthetists to have a knowledge of blood rheology. Blood rheology plays an important role in numerous clinical situations. Hemorheologic changes may significantly affect the induction and recovery times with anesthetic agents. But also, hemorheologic factors are directly or indirectly affected by many anesthetic agents or their metabolites. In this review, the blood rheology with special emphasis on its application in anesthesiology, the importance hemorheological parameters in anesthesiology and also the effect of some anesthetic substances on red blood cell rheology were presented.

  15. 21 CFR 864.8200 - Blood cell diluent.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Blood cell diluent. 864.8200 Section 864.8200 Food... DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8200 Blood cell diluent. (a) Identification. A blood cell diluent is a device used to dilute blood for further testing, such as blood cell...

  16. 21 CFR 864.8200 - Blood cell diluent.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Blood cell diluent. 864.8200 Section 864.8200 Food... DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8200 Blood cell diluent. (a) Identification. A blood cell diluent is a device used to dilute blood for further testing, such as blood cell...

  17. 21 CFR 864.8200 - Blood cell diluent.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Blood cell diluent. 864.8200 Section 864.8200 Food... DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8200 Blood cell diluent. (a) Identification. A blood cell diluent is a device used to dilute blood for further testing, such as blood cell...

  18. 21 CFR 864.8200 - Blood cell diluent.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Blood cell diluent. 864.8200 Section 864.8200 Food... DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8200 Blood cell diluent. (a) Identification. A blood cell diluent is a device used to dilute blood for further testing, such as blood cell...

  19. Nanoparticle-blood interactions: the implications on solid tumour targeting.

    PubMed

    Lazarovits, James; Chen, Yih Yang; Sykes, Edward A; Chan, Warren C W

    2015-02-18

    Nanoparticles are suitable platforms for cancer targeting and diagnostic applications. Typically, less than 10% of all systemically administered nanoparticles accumulate in the tumour. Here we explore the interactions of blood components with nanoparticles and describe how these interactions influence solid tumour targeting. In the blood, serum proteins adsorb onto nanoparticles to form a protein corona in a manner dependent on nanoparticle physicochemical properties. These serum proteins can block nanoparticle tumour targeting ligands from binding to tumour cell receptors. Additionally, serum proteins can also encourage nanoparticle uptake by macrophages, which decreases nanoparticle availability in the blood and limits tumour accumulation. The formation of this protein corona will also increase the nanoparticle hydrodynamic size or induce aggregation, which makes nanoparticles too large to enter into the tumour through pores of the leaky vessels, and prevents their deep penetration into tumours for cell targeting. Recent studies have focused on developing new chemical strategies to reduce or eliminate serum protein adsorption, and rescue the targeting potential of nanoparticles to tumour cells. An in-depth and complete understanding of nanoparticle-blood interactions is key to designing nanoparticles with optimal physicochemical properties with high tumour accumulation. The purpose of this review article is to describe how the protein corona alters the targeting of nanoparticles to solid tumours and explains current solutions to solve this problem.

  20. Mobilization of peripheral blood stem cells.

    PubMed

    Arslan, Onder; Moog, Rainer

    2007-10-01

    The use of peripheral blood stem cells (PBSC) as a source of hematopoietic stem cells is steadily increasing and has nearly supplanted bone marrow transplantation. The present article reviews mobilization of PBSC as well as the side effects. Under steady state conditions less than 0.05% of the white blood cells (WBC) are CD34+ cells. Chemotherapy results in a 5-15-fold increase of PBSC. Combining chemotherapy and growth factors increases CD34+ cells up to 6% of WBC. In the allogeneic setting, granulocyte-colony stimulating factor (G-CSF) is used alone for PBSC mobilization. Several factors affect the mobilization of PBSC: age, gender, type of growth factor, dose of the growth factor and in the autologous setting, the patient's diagnosis, chemotherapy regimen and number of previous chemotherapy cycles or radiation. Muscle and bone pain are frequent adverse events in allogeneic stem cell mobilization but are usually tolerated with the use of analgesics. Spleen enlargement followed by rupture is a serious complication in allogeneic donors. Large volume apheresis (LVL) with a processed volume of more than 4-fold of the patient's blood volume can be used to increase the CD34+ yield in patients with low CD34+ pre-counts, resulting in higher yields of CD34+ cells for transplantation. Processing of more blood in LVL is achieved by an increase of the blood flow rate and an altered anticoagulation regimen with the occurrence of more citrate reactions.

  1. Separation of blood cells using hydrodynamic lift

    NASA Astrophysics Data System (ADS)

    Geislinger, T. M.; Eggart, B.; Braunmüller, S.; Schmid, L.; Franke, T.

    2012-04-01

    Using size and deformability as intrinsic biomarkers, we separate red blood cells (RBCs) from other blood components based on a repulsive hydrodynamic cell-wall-interaction. We exploit this purely viscous lift effect at low Reynolds numbers to induce a lateral migration of soft objects perpendicular to the streamlines of the fluid, which closely follows theoretical prediction by Olla [J. Phys. II 7, 1533, (1997)]. We study the effects of flow rate and fluid viscosity on the separation efficiency and demonstrate the separation of RBCs, blood platelets, and solid microspheres from each other. The method can be used for continuous and label-free cell classification and sorting in on-chip blood analysis.

  2. Partitioning of red blood cell aggregates in bifurcating microscale flows

    NASA Astrophysics Data System (ADS)

    Kaliviotis, E.; Sherwood, J. M.; Balabani, S.

    2017-03-01

    Microvascular flows are often considered to be free of red blood cell aggregates, however, recent studies have demonstrated that aggregates are present throughout the microvasculature, affecting cell distribution and blood perfusion. This work reports on the spatial distribution of red blood cell aggregates in a T-shaped bifurcation on the scale of a large microvessel. Non-aggregating and aggregating human red blood cell suspensions were studied for a range of flow splits in the daughter branches of the bifurcation. Aggregate sizes were determined using image processing. The mean aggregate size was marginally increased in the daughter branches for a range of flow rates, mainly due to the lower shear conditions and the close cell and aggregate proximity therein. A counterintuitive decrease in the mean aggregate size was apparent in the lower flow rate branches. This was attributed to the existence of regions depleted by aggregates of certain sizes in the parent branch, and to the change in the exact flow split location in the T-junction with flow ratio. The findings of the present investigation may have significant implications for microvascular flows and may help explain why the effects of physiological RBC aggregation are not deleterious in terms of in vivo vascular resistance.

  3. Partitioning of red blood cell aggregates in bifurcating microscale flows

    PubMed Central

    Kaliviotis, E.; Sherwood, J. M.; Balabani, S.

    2017-01-01

    Microvascular flows are often considered to be free of red blood cell aggregates, however, recent studies have demonstrated that aggregates are present throughout the microvasculature, affecting cell distribution and blood perfusion. This work reports on the spatial distribution of red blood cell aggregates in a T-shaped bifurcation on the scale of a large microvessel. Non-aggregating and aggregating human red blood cell suspensions were studied for a range of flow splits in the daughter branches of the bifurcation. Aggregate sizes were determined using image processing. The mean aggregate size was marginally increased in the daughter branches for a range of flow rates, mainly due to the lower shear conditions and the close cell and aggregate proximity therein. A counterintuitive decrease in the mean aggregate size was apparent in the lower flow rate branches. This was attributed to the existence of regions depleted by aggregates of certain sizes in the parent branch, and to the change in the exact flow split location in the T-junction with flow ratio. The findings of the present investigation may have significant implications for microvascular flows and may help explain why the effects of physiological RBC aggregation are not deleterious in terms of in vivo vascular resistance. PMID:28303921

  4. Deterministic Aperiodic Sickle Cell Blood Flows

    NASA Astrophysics Data System (ADS)

    Atsaves, Louis; Harris, Wesley

    2013-11-01

    In this paper sickle cell blood flow in the capillaries is modeled as a hydrodynamical system. The hydrodynamical system consists of the axisymmetric unsteady, incompressible Navier-Stokes equations and a set of constitutive equations for oxygen transport. Blood cell deformation is not considered in this paper. The hydrodynamical system is reduced to a system of non-linear partial differential equations that are then transformed into a system of three autonomous non-linear ordinary differential equations and a set of algebraic equations. We examine the hydrodynamical system to discern stable/unstable, periodic/nonperiodic, reversible/irreversible properties of the system. The properties of the solutions are driven in large part by the coefficients of the governing system of equations. These coefficients depend on the physiological properties of the sickle cell blood. The chaotic nature of the onset of crisis in sickle cell patients is identified. Research Assistant.

  5. 21 CFR 864.9245 - Automated blood cell separator.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Automated blood cell separator. 864.9245 Section... Blood and Blood Products § 864.9245 Automated blood cell separator. (a) Identification. An automated blood cell separator is a device that uses a centrifugal or filtration separation principle to...

  6. 21 CFR 864.9245 - Automated blood cell separator.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Automated blood cell separator. 864.9245 Section... Blood and Blood Products § 864.9245 Automated blood cell separator. (a) Identification. An automated blood cell separator is a device that uses a centrifugal or filtration separation principle to...

  7. 21 CFR 864.9245 - Automated blood cell separator.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Automated blood cell separator. 864.9245 Section... Blood and Blood Products § 864.9245 Automated blood cell separator. (a) Identification. An automated blood cell separator is a device that uses a centrifugal or filtration separation principle to...

  8. 21 CFR 864.9245 - Automated blood cell separator.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Automated blood cell separator. 864.9245 Section... Blood and Blood Products § 864.9245 Automated blood cell separator. (a) Identification. An automated blood cell separator is a device that uses a centrifugal or filtration separation principle to...

  9. 21 CFR 864.9245 - Automated blood cell separator.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Automated blood cell separator. 864.9245 Section... Blood and Blood Products § 864.9245 Automated blood cell separator. (a) Identification. An automated blood cell separator is a device that uses a centrifugal or filtration separation principle to...

  10. Multiscale simulation of red blood cell aggregation

    NASA Astrophysics Data System (ADS)

    Bagchi, P.; Popel, A. S.

    2004-11-01

    In humans and other mammals, aggregation of red blood cells (RBC) is a major determinant to blood viscosity in microcirculation under physiological and pathological conditions. Elevated levels of aggregation are often related to cardiovascular diseases, bacterial infection, diabetes, and obesity. Aggregation is a multiscale phenomenon that is governed by the molecular bond formation between adjacent cells, morphological and rheological properties of the cells, and the motion of the extra-cellular fluid in which the cells circulate. We have developed a simulation technique using front tracking methods for multiple fluids that includes the multiscale characteristics of aggregation. We will report the first-ever direct computer simulation of aggregation of deformable cells in shear flows. We will present results on the effect of shear rate, strength of the cross-bridging bonds, and the cell rheological properties on the rolling motion, deformation and subsequent breakage of an aggregate.

  11. Whole Blood Cell Staining Device

    NASA Technical Reports Server (NTRS)

    Sams, Clarence F.; Clift, Vaughan L.; McDonald, Kelly E.

    2000-01-01

    An apparatus and method for staining particular cell markers is disclosed. The apparatus includes a flexible tube that is reversibly pinched into compartments with one or more clamps. Each compartment of the tube contains a separate reagent and is in selective fluid communication with adjoining compartments.

  12. Red blood cell transfusion in newborn infants

    PubMed Central

    Whyte, Robin K; Jefferies, Ann L

    2014-01-01

    Red blood cell transfusion is an important and frequent component of neonatal intensive care. The present position statement addresses the methods and indications for red blood cell transfusion of the newborn, based on a review of the current literature. The most frequent indications for blood transfusion in the newborn are the acute treatment of perinatal hemorrhagic shock and the recurrent correction of anemia of prematurity. Perinatal hemorrhagic shock requires immediate treatment with large quantities of red blood cells; the effects of massive transfusion on other blood components must be considered. Some guidelines are now available from clinical trials investigating transfusion in anemia of prematurity; however, considerable uncertainty remains. There is weak evidence that cognitive impairment may be more severe at follow-up in extremely low birth weight infants transfused at lower hemoglobin thresholds; therefore, these thresholds should be maintained by transfusion therapy. Although the risks of transfusion have declined considerably in recent years, they can be minimized further by carefully restricting neonatal blood sampling. PMID:24855419

  13. Red blood cell clustering in Poiseuille microcapillary flow

    NASA Astrophysics Data System (ADS)

    Tomaiuolo, Giovanna; Lanotte, Luca; Ghigliotti, Giovanni; Misbah, Chaouqi; Guido, Stefano

    2012-05-01

    Red blood cells (RBC) flowing in microcapillaries tend to associate into clusters, i.e., small trains of cells separated from each other by a distance comparable to cell size. This process is usually attributed to slower RBCs acting to create a sequence of trailing cells. Here, based on the first systematic investigation of collective RBC flow behavior in microcapillaries in vitro by high-speed video microscopy and numerical simulations, we show that RBC size polydispersity within the physiological range does not affect cluster stability. Lower applied pressure drops and longer residence times favor larger RBC clusters. A limiting cluster length, depending on the number of cells in a cluster, is found by increasing the applied pressure drop. The insight on the mechanism of RBC clustering provided by this work can be applied to further our understanding of RBC aggregability, which is a key parameter implicated in clotting and thrombus formation.

  14. Recent developments in blood cell labeling research

    SciTech Connect

    Srivastava, S.C.; Straub, R.F.; Meinken, G.E.

    1988-09-07

    A number of recent developments in research on blood cell labeling techniques are presented. The discussion relates to three specific areas: (1) a new in vitro method for red blood cell labeling with /sup 99m/Tc; (2) a method for labeling leukocytes and platelets with /sup 99m/Tc; and (3) the use of monoclonal antibody technique for platelet labeling. The advantages and the pitfalls of these techniques are examined in the light of available mechanistic information. Problems that remain to be resolved are reviewed. An assessment is made of the progress as well as prospects in blood cell labeling methodology including that using the monoclonal antibody approach. 37 refs., 4 figs.

  15. Membrane Stability during Biopreservation of Blood Cells

    PubMed Central

    Stoll, Christoph; Wolkers, Willem F.

    2011-01-01

    Summary Storage methods, which can be taken into consideration for red blood cells and platelets, include liquid storage, cryopreservation and freeze-drying. Red blood cells can be hypothermically stored at refrigerated temperatures, whereas platelets are chilling sensitive and therefore cannot be stored at temperatures below 20 °C. Here we give an overview of available cryopreservation and freeze-drying procedures for blood cells and discuss the effects of these procedures on cells, particularly on cellular membranes. Cryopreservation and freeze-drying may result in chemical and structural modifications of cellular membranes. Membranes undergo phase and permeability changes during freezing and drying. Cryo- and lyoprotective agents prevent membrane damage by different mechanisms. Cryoprotective agents are preferentially excluded from membrane surfaces. They decrease the activation energy for water transport during freezing and control the rate of cellular dehydration. Lyoprotectants are thought to stabilize membranes during drying by forming direct hydrogen bonding interactions with phospholipid head groups. In addition, lyoprotectants can form a glassy state at room temperature. Recently liposomes have been investigated to stabilize blood cells during freezing and freeze-drying. Liposomes modify the composition of cellular membranes by lipid and cholesterol transfer, which can stabilize or destabilize the low temperature response of cells. PMID:21566710

  16. Exploiting osmosis for blood cell sorting.

    PubMed

    Parichehreh, Vahidreza; Estrada, Rosendo; Kumar, Srikanth Suresh; Bhavanam, Kranthi Kumar; Raj, Vinay; Raj, Ashok; Sethu, Palaniappan

    2011-06-01

    Blood is a valuable tissue containing cellular populations rich in information regarding the immediate immune and inflammatory status of the body. Blood leukocytes or white blood cells (WBCs) provide an ideal sample to monitor systemic changes and understand molecular signaling mechanisms in disease processes. Blood samples need to be processed to deplete contaminating erythrocytes or red blood cells (RBCs) and sorted into different WBC sub-populations prior to analysis. This is typically accomplished using immuno-affinity protocols which result in undesirable activation. An alternative is size based sorting which by itself is unsuitable for WBCs sorting due to size overlap between different sub-populations. To overcome this limitation, we investigated the possibility of using controlled osmotic exposure to deplete and/or create a differential size increase between WBC populations. Using a new microfluidic cell docking platform, the response of RBCs and WBCs to deionized (DI) water was evaluated. Time lapse microscopy confirms depletion of RBCs within 15 s and creation of > 3 μm size difference between lymphocytes, monocytes and granulocytes. A flow through microfluidic device was also used to expose different WBCs to DI water for 30, 60 and 90 s to quantify cell loss and activation. Results confirm preservation of ~100% of monocytes, granulocytes and loss of ~30% of lymphocytes (mostly CD3+/CD4+) with minimal activation. These results indicate feasibility of this approach for monocyte, granulocyte and lymphocyte (sub-populations) isolation based on size.

  17. P2X and P2Y receptor signaling in red blood cells.

    PubMed

    Sluyter, Ronald

    2015-01-01

    Purinergic signaling involves the activation of cell surface P1 and P2 receptors by extracellular nucleosides and nucleotides such as adenosine and adenosine triphosphate (ATP), respectively. P2 receptors comprise P2X and P2Y receptors, and have well-established roles in leukocyte and platelet biology. Emerging evidence indicates important roles for these receptors in red blood cells. P2 receptor activation stimulates a number of signaling pathways in progenitor red blood cells resulting in microparticle release, reactive oxygen species formation, and apoptosis. Likewise, activation of P2 receptors in mature red blood cells stimulates signaling pathways mediating volume regulation, eicosanoid release, phosphatidylserine exposure, hemolysis, impaired ATP release, and susceptibility or resistance to infection. This review summarizes the distribution of P2 receptors in red blood cells, and outlines the functions of P2 receptor signaling in these cells and its implications in red blood cell biology.

  18. Cancer cells in the circulating blood

    PubMed Central

    Sato, Haruo

    1962-01-01

    The author discusses the relation between the presence of cancer cells in the circulating blood and the development of metastasis, as demonstrated by studies on animals with experimentally induced tumours, by post-mortem studies on fatal human cases of cancer, and by studies on patients operated upon for stomach cancer. Although the correlation between the presence of tumour cells in the blood and the occurrence of metastatic lesions was found to be less close in the human cases of cancer than in the experimental animals, the author considers that it was sufficiently marked to justify the assumption that the appearance of tumour cells in the circulating blood is an important link in the chain of processes leading to cancer metastasis. In conclusion, the author puts forward the suggestion, based on the results of animal experiments, that chemotherapy might have an inhibitory effect on the liberated tumour cells in the blood, particularly if these cells are present only in small numbers, and thus be instrumental in halting the course of metastasis. PMID:14497407

  19. Red blood cells in retinal vascular disorders.

    PubMed

    Agrawal, Rupesh; Sherwood, Joseph; Chhablani, Jay; Ricchariya, Ashutosh; Kim, Sangho; Jones, Philip H; Balabani, Stavroula; Shima, David

    2016-01-01

    Microvascular circulation plays a vital role in regulating physiological functions, such as vascular resistance, and maintaining organ health. Pathologies such as hypertension, diabetes, or hematologic diseases affect the microcirculation posing a significant risk to human health. The retinal vasculature provides a unique window for non-invasive visualisation of the human circulation in vivo and retinal vascular image analysis has been established to predict the development of both clinical and subclinical cardiovascular, metabolic, renal and retinal disease in epidemiologic studies. Blood viscosity which was otherwise thought to play a negligible role in determining blood flow based on Poiseuille's law up to the 1970s has now been shown to play an equally if not a more important role in controlling microcirculation and quantifying blood flow. Understanding the hemodynamics/rheology of the microcirculation and its changes in diseased states remains a challenging task; this is due to the particulate nature of blood, the mechanical properties of the cells (such as deformability and aggregability) and the complex architecture of the microvasculature. In our review, we have tried to postulate a possible role of red blood cell (RBC) biomechanical properties and laid down future framework for research related to hemorrheological aspects of blood in patients with retinal vascular disorders.

  20. Microfluidic immunomagnetic cell separation from whole blood.

    PubMed

    Bhuvanendran Nair Gourikutty, Sajay; Chang, Chia-Pin; Puiu, Poenar Daniel

    2016-02-01

    Immunomagnetic-based separation has become a viable technique for the separation of cells and biomolecules. Here we report on the design and analysis of a simple and efficient microfluidic device for high throughput and high efficiency capture of cells tagged with magnetic particles. This is made possible by using a microfluidic chip integrated with customized arrays of permanent magnets capable of creating large magnetic field gradients, which determine the effective capturing of the tagged cells. This method is based on manipulating the cells which are under the influence of a combination of magnetic and fluid dynamic forces in a fluid under laminar flow through a microfluidic chip. A finite element analysis (FEA) model is developed to analyze the cell separation process and predict its behavior, which is validated subsequently by the experimental results. The magnetic field gradients created by various arrangements of magnetic arrays have been simulated using FEA and the influence of these field gradients on cell separation has been studied with the design of our microfluidic chip. The proof-of-concept for the proposed technique is demonstrated by capturing white blood cells (WBCs) from whole human blood. CD45-conjugated magnetic particles were added into whole blood samples to label WBCs and the mixture was flown through our microfluidic device to separate the labeled cells. After the separation process, the remaining WBCs in the elute were counted to determine the capture efficiency, and it was found that more than 99.9% WBCs have been successfully separated from whole blood. The proposed design can be used for positive selection as well as for negative enrichment of rare cells.

  1. Potential implications of vascular wall resident endothelial progenitor cells.

    PubMed

    Ergün, Süleyman; Tilki, Derya; Hohn, Hans-Peter; Gehling, Ursula; Kilic, Nerbil

    2007-11-01

    A rapidly increasing body of data suggests an essential role of endothelial progenitor cells (EPCs) in vascular regeneration, formation of new vessels in cardiovascular diseases and also in tumor vasculogenesis. Moreover, recent data obtained from clinical studies with anti-angiogenic drugs in tumor therapy or with pro-angiogenic stimuli in ischemic disorders implicate a predictive role of the number of EPCs circulating in the peripheral blood in monitoring of these diseases. However, there is still some controversial data regarding the relevance of the EPCs in vascular formation depending on models used and diseases studied. One of the essential prerequisites for a better understanding of the whole contribution of EPCs to vascular formation in adult, a process called postnatal vasculogenesis, is to identify their exact sources. We could recently discover the existence of EPCs in a distinct zone of the vascular wall of large and middle sized adult blood vessels and showed that these cells are capable to differentiate into mature endothelial cells, to form capillary sprouts in arterial ring assay and to build vasa vasorum-like structures within the vascular wall. They also can be mobilized very rapidly from the vascular wall by tumor cells. This review will discuss the functional implications of these vascular wall resident endothelial progenitor cells (VW-EPCs) in relation to those of EPCs circulating in peripheral blood or derived from the bone marrow in cardiovascular and neoplastic diseases.

  2. Development of autologous blood cell therapies.

    PubMed

    Kim, Ah Ram; Sankaran, Vijay G

    2016-10-01

    Allogeneic hematopoietic stem cell transplantation and blood cell transfusions are performed commonly in patients with a variety of blood disorders. Unfortunately, these donor-derived cell therapies are constrained due to limited supplies, infectious risk factors, a lack of appropriately matched donors, and the risk of immunologic complications from such products. The use of autologous cell therapies has been proposed to overcome these shortcomings. One can derive such therapies directly from hematopoietic stem and progenitor cells of individuals, which can then be manipulated ex vivo to produce the desired modifications or differentiated to produce a particular target population. Alternatively, pluripotent stem cells, which have a theoretically unlimited self-renewal capacity and an ability to differentiate into any desired cell type, can be used as an autologous starting source for such manipulation and differentiation approaches. Such cell products can also be used as a delivery vehicle for therapeutics. In this review, we highlight recent advances and discuss ongoing challenges for the in vitro generation of autologous hematopoietic cells that can be used for cell therapy. Copyright © 2016 ISEH - International Society for Experimental Hematology. Published by Elsevier Inc. All rights reserved.

  3. The frequency and proliferative potential of megakaryocytic colony-forming cells (Meg-CFC) in cord blood, cytokine-mobilized peripheral blood and bone marrow, and their correlation with total CFC numbers: implications for the quantitation of Meg-CFC to predict platelet engraftment following cord blood transplantation.

    PubMed

    Drygalski, A; Xu, G; Constantinescu, D; Kashiwakura, I; Farley, T; Dobrila, L; Rubinstein, P; Adamson, J W

    2000-05-01

    CFC numbers have shown to correlate with success of engraftment and speed of neutrophil recovery following cord blood (CB) transplantation. To investigate whether the number of Meg-CFC in a CB stem cell preparation might correlate with time to platelet engraftment, we evaluated the frequency of Meg-CFC among all CFC types in 134 CB, 21 adult bone marrow (BM) and 52 cytokine-mobilized peripheral blood (PB) stem cell preparations. The correlation of Meg-CFC with the total number of CFC and mixed cell-CFC was also assessed. The frequency of Meg-CFC was highest in CB and correlated significantly with total CFC numbers (mean 20.8%, correlation coefficient (r) 0.84, P = 0.0001) compared with Meg-CFC from mobilized PB (mean 13.1%, r = 0.29, P = 0.07) and BM (mean 4%, r = 0. 39, P = 0.13). In addition, mixed-cell CFC numbers in CB were highly correlated with the total number of Meg-CFC (r = 0.7, P = 0.0001). No such correlations were found with mobilized PB or BM. We conclude that, based on the high degree of correlation between Meg-CFC and non-Meg-CFC numbers in CB, no additional information concerning time to platelet engraftment would be gained by routinely performing Meg-CFC assays in addition to non-Meg-CFC assays. The fact that CB Meg-CFC and mixed-cell CFC are strongly correlated suggests that CB Meg-CFC are more primitive than their counterparts in BM and PB and may reflect the number of stem cells in CB. Bone Marrow Transplantation (2000).

  4. White blood cell counts: reference methodology.

    PubMed

    Chabot-Richards, Devon S; George, Tracy I

    2015-03-01

    Modern hematology laboratories use automated hematology analyzers to perform cell counts. These instruments provide accurate, precise, low-cost differential counts with fast turnaround times. Technologies commonly used include electrical impedance, radiofrequency conductivity, laser light scattering, and cytochemistry. This article reviews the principles of these methodologies and possible sources of error, provides guidance for selecting flagging criteria, and discusses novel, clinically relevant white blood cell parameters provided by new instruments, including immature granulocyte count and granularity index.

  5. Photomodification of human immunocompetent blood cells

    SciTech Connect

    Krylenkov, V.A.; Ogurtsov, R.P.; Osmanov, M.A.; Kholmogorov, V.E.

    1987-10-01

    In this paper, processes of photomodification of lymphoid cells in human blood, developing immediately after exposure to visible radiation and also in the late stages after irradiation, were investigated by methods of spontaneous and immune rosette formation and the blast transformation test, combined with treatment with the antioxidant alpha-tocopherol and the radioactive assessment of spontaneous and stimulated DNA synthesis by tritium-thymidine-labelled cells.

  6. Sorting white blood cells in microfabricated arrays

    NASA Astrophysics Data System (ADS)

    Castelino, Judith Andrea Rose

    Fractionating white cells in microfabricated arrays presents the potential for detecting cells with abnormal adhesive or deformation properties. A possible application is separating nucleated fetal red blood cells from maternal blood. Since fetal cells are nucleated, it is possible to extract genetic information about the fetus from them. Separating fetal cells from maternal blood would provide a low cost noninvasive prenatal diagnosis for genetic defects, which is not currently available. We present results showing that fetal cells penetrate further into our microfabricated arrays than adult cells, and that it is possible to enrich the fetal cell fraction using the arrays. We discuss modifications to the array which would result in further enrichment. Fetal cells are less adhesive and more deformable than adult white cells. To determine which properties limit penetration, we compared the penetration of granulocytes and lymphocytes in arrays with different etch depths, constriction size, constriction frequency, and with different amounts of metabolic activity. The penetration of lymphocytes and granulocytes into constrained and unconstrained arrays differed qualitatively. In constrained arrays, the cells were activated by repeated shearing, and the number of cells stuck as a function of distance fell superexponentially. In unconstrained arrays the number of cells stuck fell slower than an exponential. We attribute this result to different subpopulations of cells with different sticking parameters. We determined that penetration in unconstrained arrays was limited by metabolic processes, and that when metabolic activity was reduced penetration was limited by deformability. Fetal cells also contain a different form of hemoglobin with a higher oxygen affinity than adult hemoglobin. Deoxygenated cells are paramagnetic and are attracted to high magnetic field gradients. We describe a device which can separate cells using 10 μm magnetic wires to deflect the paramagnetic

  7. Mitochondrial dysfunction in blood cells from amyotrophic lateral sclerosis patients.

    PubMed

    Ehinger, Johannes K; Morota, Saori; Hansson, Magnus J; Paul, Gesine; Elmér, Eskil

    2015-06-01

    Mitochondrial dysfunction is implicated in amyotrophic lateral sclerosis, where the progressive degeneration of motor neurons results in muscle atrophy, paralysis and death. Abnormalities in both central nervous system and muscle mitochondria have previously been demonstrated in patient samples, indicating systemic disease. In this case-control study, venous blood samples were acquired from 24 amyotrophic lateral sclerosis patients and 21 age-matched controls. Platelets and peripheral blood mononuclear cells were isolated and mitochondrial oxygen consumption measured in intact and permeabilized cells with additions of mitochondrial substrates, inhibitors and titration of an uncoupler. Respiratory values were normalized to cell count and for two markers of cellular mitochondrial content, citrate synthase activity and mitochondrial DNA, respectively. Mitochondrial function was correlated with clinical staging of disease severity. Complex IV (cytochrome c-oxidase)-activity normalized to mitochondrial content was decreased in platelets from amyotrophic lateral sclerosis patients both when normalized to citrate synthase activity and mitochondrial DNA copy number. In mononuclear cells, complex IV-activity was decreased when normalized to citrate synthase activity. Mitochondrial content was increased in amyotrophic lateral sclerosis patient platelets. In mononuclear cells, complex I activity declined and mitochondrial content increased progressively with advancing disease stage. The findings are, however, based on small subsets of patients and need to be confirmed. We conclude that when normalized to mitochondria-specific content, complex IV-activity is reduced in blood cells from amyotrophic lateral sclerosis patients and that there is an apparent compensatory increase in cellular mitochondrial content. This supports systemic involvement in amyotrophic lateral sclerosis and suggests further study of mitochondrial function in blood cells as a future biomarker for the

  8. Inflight Assay of Red Blood Cell Deformability

    NASA Technical Reports Server (NTRS)

    Ingram, M.; Paglia, D. E.; Eckstein, E. C.; Frazer, R. E.

    1985-01-01

    Studies on Soviet and American astronauts have demonstrated that red blood cell production is altered in response to low gravity (g) environment. This is associated with changes in individual red cells including increased mean cell volume and altered membrane deformability. During long orbital missions, there is a tendency for the red cell mass deficit to be at least partly corrected although the cell shape anomalies are not. Data currently available suggest that the observed decrease in red cell mass is the result of sudden suppression of erythropoieses and that the recovery trend observed during long missions reflects re-establishment of erythropoietic homeostasis at a "set point" for the red cell mass that is slightly below the normal level at 1 g.

  9. Inflight Assay of Red Blood Cell Deformability

    NASA Technical Reports Server (NTRS)

    Ingram, M.; Paglia, D. E.; Eckstein, E. C.; Frazer, R. E.

    1985-01-01

    Studies on Soviet and American astronauts have demonstrated that red blood cell production is altered in response to low gravity (g) environment. This is associated with changes in individual red cells including increased mean cell volume and altered membrane deformability. During long orbital missions, there is a tendency for the red cell mass deficit to be at least partly corrected although the cell shape anomalies are not. Data currently available suggest that the observed decrease in red cell mass is the result of sudden suppression of erythropoieses and that the recovery trend observed during long missions reflects re-establishment of erythropoietic homeostasis at a "set point" for the red cell mass that is slightly below the normal level at 1 g.

  10. Aggregation of mononuclear and red blood cells through an {alpha}4{beta}1-Lu/basal cell adhesion molecule interaction in sickle cell disease.

    PubMed

    Chaar, Vicky; Picot, Julien; Renaud, Olivier; Bartolucci, Pablo; Nzouakou, Ruben; Bachir, Dora; Galactéros, Frédéric; Colin, Yves; Le Van Kim, Caroline; El Nemer, Wassim

    2010-11-01

    Abnormal interactions between red blood cells, leukocytes and endothelial cells play a critical role in the occurrence of the painful vaso-occlusive crises associated with sickle cell disease. We investigated the interaction between circulating leukocytes and red blood cells which could lead to aggregate formation, enhancing the incidence of vaso-occlusive crises. Blood samples from patients with sickle cell disease (n=25) and healthy subjects (n=5) were analyzed by imaging and classical flow cytometry after density gradient separation. The identity of the cells in the peripheral blood mononuclear cell layer was determined using antibodies directed specifically against white (anti-CD45) or red (anti-glycophorin A) blood cells. Aggregates between red blood cells and peripheral blood mononuclear cells were visualized in whole blood from patients with sickle cell disease. The aggregation rate was 10-fold higher in these patients than in control subjects. Both mature red blood cells and reticulocytes were involved in these aggregates through their interaction with mononuclear cells, mainly with monocytes. The size of the aggregates was variable, with one mononuclear cell binding to one, two or several red blood cells. Erythroid Lu/basal cell adhesion molecule and α(4)β(1) integrin were involved in aggregate formation. The aggregation rate was lower in patients treated with hydroxycarbamide than in untreated patients. Our study gives visual evidence of the existence of circulating red blood cell-peripheral blood mononuclear cell aggregates in patients with sickle cell disease and shows that these aggregates are decreased during hydroxycarbamide treatment. Our results strongly suggest that erythroid Lu/basal cell adhesion molecule proteins are implicated in these aggregates through their interaction with α(4)β(1) integrin on peripheral blood mononuclear cells.

  11. Red blood cell alloimmunization among sickle cell Kuwaiti Arab patients who received red blood cell transfusion.

    PubMed

    Ameen, Reem; Al Shemmari, Salem; Al-Bashir, Abdulaziz

    2009-08-01

    Sickle cell disease (SCD) is common in the Arabian Gulf region. Most cases require a red blood cell (RBC) transfusion, increasing the potential for RBC alloantibody development. The incidence of RBC alloimmunization among Kuwaiti Arab SCD patients is not yet known. This study retrospectively assessed the effect of using two different matching protocols on the incidence of alloimmunization among multiply transfused Kuwaiti Arab SCD patients. A total of 233 Kuwaiti Arab SCD patients were divided into two groups: Group 1 (n = 110) received RBC transfusion through standard ABO- and D-matched nonleukoreduced blood; Group 2 (n = 123) received RBCs matched for ABO, Rh, and K1 poststorage-leukoreduced blood. Multivariate analysis was performed on the factors associated with RBC alloimmunization and antibody specificity. Sixty-five percent of patients in Group 1 developed clinically significant RBC alloantibody with an increased prevalence in females; in patients in Group 2, 23.6% developed RBC alloantibodies (p = 0.01). In Group 1, 72 patients (65.5%) had alloantibodies directed against Rh and Kell systems (p = 0.01). Multivariate analysis further confirmed the results, showing that blood transfusion type and sex have significant effects on the rate of alloimmunizations. This study confirms the importance of selecting RBCs matched for Rh and Kell to reduce the risk of alloimmunizations among Kuwaiti Arab SCD patients.

  12. Red blood cell transfusion in clinical practice.

    PubMed

    Klein, Harvey G; Spahn, Donat R; Carson, Jeffrey L

    2007-08-04

    Every year, about 75 million units of blood are collected worldwide. Red blood cell (RBC) transfusion is one of the few treatments that adequately restore tissue oxygenation when oxygen demand exceeds supply. Although the respiratory function of blood has been studied intensively, the trigger for RBC transfusion remains controversial, and doctors rely primarily on clinical experience. Laboratory assays that indicate failing tissue oxygenation would be ideal to guide the need for transfusion, but none has proved easy, reproducible, and sensitive to regional tissue hypoxia. The clinical importance of the RBCs storage lesion (ie, the time-dependent metabolic, biochemical, and molecular changes that stored blood cells undergo) is poorly understood. RBCs can be filtered, washed, frozen, or irradiated for specific indications. Donor screening and testing have dramatically reduced infectious risks in the developed world, but infection remains a major hazard in developing countries, where 13 million units of blood are not tested for HIV or hepatitis viruses. Pathogen inactivation techniques are in clinical trials for RBCs, but none is available for use. Despite serious immunological and non-immunological complications, RBC transfusion holds a therapeutic index that exceeds that of many common medications.

  13. Osmotic parameters of red blood cells from umbilical cord blood.

    PubMed

    Zhurova, Mariia; McGann, Locksley E; Acker, Jason P

    2014-06-01

    The transfusion of red blood cells from umbilical cord blood (cord RBCs) is gathering significant interest for the treatment of fetal and neonatal anemia, due to its high content of fetal hemoglobin as well as numerous other potential benefits to fetuses and neonates. However, in order to establish a stable supply of cord RBCs for clinical use, a cryopreservation method must be developed. This, in turn, requires knowledge of the osmotic parameters of cord RBCs. Thus, the objective of this study was to characterize the osmotic parameters of cord RBCs: osmotically inactive fraction (b), hydraulic conductivity (Lp), permeability to cryoprotectant glycerol (Pglycerol), and corresponding Arrhenius activation energies (Ea). For Lp and Pglycerol determination, RBCs were analyzed using a stopped-flow system to monitor osmotically-induced RBC volume changes via intrinsic RBC hemoglobin fluorescence. Lp and Pglycerol were characterized at 4°C, 20°C, and 35°C using Jacobs and Stewart equations with the Ea calculated from the Arrhenius plot. Results indicate that cord RBCs have a larger osmotically inactive fraction compared to adult RBCs. Hydraulic conductivity and osmotic permeability to glycerol of cord RBCs differed compared to those of adult RBCs with the differences dependent on experimental conditions, such as temperature and osmolality. Compared to adult RBCs, cord RBCs had a higher Ea for Lp and a lower Ea for Pglycerol. This information regarding osmotic parameters will be used in future work to develop a protocol for cryopreserving cord RBCs.

  14. Interferometric phase microscopy of red blood cells

    NASA Astrophysics Data System (ADS)

    Xue, Liang; Sun, Nan; Tang, Xian; Wang, Yin; Wang, Shouyu

    2013-12-01

    Quantitative phase imaging of cells with high accuracy in a completely noninvasive manner is a challenging task. To provide a proper solution to this important need, interferometric phase microscopy is described which relies on the off-axis interferometry, confocal microscopy and high-speed image capture technology. Phase retrieval from the single interferogram is done by algorithms based on the fast Fourier transform, traditional Hilbert transform and two-step Hilbert transform, respectively. Furthermore, a phase aberrations compensation approach is applied to correct the phase distribution of the red blood cells obtained via the three methods mentioned before without the pre-known knowledge for removing the wave front curvature introduced by the microscope objectives, off-axis imaging, etc., which otherwise hinders the phase reconstruction. The improved results reveal the better inner structures of the red blood cells. The development of quantitative phase imaging technique is shedding light on their future directions and applications for basic and clinical research.

  15. Reversibility of red blood cell deformation

    NASA Astrophysics Data System (ADS)

    Zeitz, Maria; Sens, P.

    2012-05-01

    The ability of cells to undergo reversible shape changes is often crucial to their survival. For red blood cells (RBCs), irreversible alteration of the cell shape and flexibility often causes anemia. Here we show theoretically that RBCs may react irreversibly to mechanical perturbations because of tensile stress in their cytoskeleton. The transient polymerization of protein fibers inside the cell seen in sickle cell anemia or a transient external force can trigger the formation of a cytoskeleton-free membrane protrusion of μm dimensions. The complex relaxation kinetics of the cell shape is shown to be responsible for selecting the final state once the perturbation is removed, thereby controlling the reversibility of the deformation. In some case, tubular protrusion are expected to relax via a peculiar “pearling instability.”

  16. Reversibility of red blood cell deformation.

    PubMed

    Zeitz, Maria; Sens, P

    2012-05-01

    The ability of cells to undergo reversible shape changes is often crucial to their survival. For red blood cells (RBCs), irreversible alteration of the cell shape and flexibility often causes anemia. Here we show theoretically that RBCs may react irreversibly to mechanical perturbations because of tensile stress in their cytoskeleton. The transient polymerization of protein fibers inside the cell seen in sickle cell anemia or a transient external force can trigger the formation of a cytoskeleton-free membrane protrusion of μm dimensions. The complex relaxation kinetics of the cell shape is shown to be responsible for selecting the final state once the perturbation is removed, thereby controlling the reversibility of the deformation. In some case, tubular protrusion are expected to relax via a peculiar "pearling instability."

  17. Banking on cord blood stem cells.

    PubMed

    Sullivan, Michael J

    2008-07-01

    Umbilical cord blood gifted to non-profit public cord blood banks is now routinely used as an alternative source of haematopoietic stem cells for allogeneic transplantation for children and adults with cancer, bone marrow failure syndromes, haemoglobinopathies and many genetic metabolic disorders. Because of the success and outcomes of public cord banking, many companies now provide private cord banking services. However, in the absence of any published transplant evidence to support autologous and non-directed family banking, commercial cord banks currently offer a superfluous service.

  18. The antibody approach of labeling blood cells

    SciTech Connect

    Srivastava, S.C.

    1992-12-31

    Although the science of blood cell labeling using monoclonal antibodies directed against specific cellular antigens is still in its early stages, considerable progress has recently been accomplished in this area. The monoclonal antibody approach offers the promise of greater selectivity and enhanced convenience since specific cell types can be labeled in vivo, thus eliminating the need for complex and damaging cell separation procedures. This article focuses on these developments with primary emphasis on antibody labeling of platelets and leukocytes. The advantages and the shortcomings of the recently reported techniques are critically assessed and evaluated.

  19. The antibody approach of labeling blood cells

    SciTech Connect

    Srivastava, S.C.

    1991-12-31

    Although the science of blood cell labeling using monoclonal antibodies directed against specific cellular antigens is still in its early stages, considerable progress has recently been accomplished in this area. The monoclonal antibody approach offers the promise of greater selectivity and enhanced convenience since specific cell types can be labeled in vivo, thus eliminating the need for complex and damaging cell separation procedures. This article focuses on these developments with primary emphasis on antibody labeling of platelets and leukocytes. The advantages and the shortcomings of the recently reported techniques are criticality assessed and evaluated.

  20. The antibody approach of labeling blood cells

    SciTech Connect

    Srivastava, S.C.

    1991-01-01

    Although the science of blood cell labeling using monoclonal antibodies directed against specific cellular antigens is still in its early stages, considerable progress has recently been accomplished in this area. The monoclonal antibody approach offers the promise of greater selectivity and enhanced convenience since specific cell types can be labeled in vivo, thus eliminating the need for complex and damaging cell separation procedures. This article focuses on these developments with primary emphasis on antibody labeling of platelets and leukocytes. The advantages and the shortcomings of the recently reported techniques are criticality assessed and evaluated.

  1. [Production of mature red blood cell by using peripheral blood mononuclear cells].

    PubMed

    Jia, Yan-Jun; Liu, Jiang; Zhang, Ke-Ying; Shang, Xiao-Yan; Li, Wei; Wang, Li-Jun; Liu, Na; Wang, Lin; Cui, Shuang; Ni, Lei; Zhao, Bo-Tao; Wang, Dong-Mei; Gao, Song-Ming; Zhang, Zhi-Xin

    2014-10-01

    Most protocols for in vitro producing red blood cells (RBC) use the CD34(+) cells or embryonic stem cells from cord blood, bone marrow or peripheral blood as the start materials. This study was purposed to produce the mature RBC in vitro by using peripheral blood mononuclear cells as start material. The peripheral blood mononuclear cells (PBMNC) were isolated from buffy coat after blood leukapheresis, the mature red blood cells (RBC) were prepared by a 4-step culture protocol. The results showed that after culture by inducing with the different sets of cytokines and supporting by mouse MS-5 cell line, the expansion of PBMNC reached about 1000 folds at the end of the culture. About 90% of cultured RBC were enucleated mature cells which had the comparable morphological characteristics with normal RBC. Colony-forming assays showed that this culture system could stimulate the proliferation of progenitors in PBMNC and differentiate into erythroid cells. The structure and function analysis indicated that the mean cell volume of in vitro cultured RBC was 118 ± 4 fl, which was slight larger than that of normal RBC (80-100 fl); the mean cell hemoglobin was 36 ± 1.2 pg, which was slight higher than that of normal RBC (27-31 pg); the maximal deformation index was 0.46, which approachs level of normal RBC; the glucose-6-phosphate dehydrogenase and pyrurvate kinase levels was consistant with young RBC. It is concluded that PBMNC are feasble, convenient and low-cost source for producing cultured RBC and this culture system is suitable to generate the RBC from PBMNC.

  2. Anemia and red blood cell transfusion in neurocritical care

    PubMed Central

    Kramer, Andreas H; Zygun, David A

    2009-01-01

    Introduction Anemia is one of the most common medical complications to be encountered in critically ill patients. Based on the results of clinical trials, transfusion practices across the world have generally become more restrictive. However, because reduced oxygen delivery contributes to 'secondary' cerebral injury, anemia may not be as well tolerated among neurocritical care patients. Methods The first portion of this paper is a narrative review of the physiologic implications of anemia, hemodilution, and transfusion in the setting of brain-injury and stroke. The second portion is a systematic review to identify studies assessing the association between anemia or the use of red blood cell transfusions and relevant clinical outcomes in various neurocritical care populations. Results There have been no randomized controlled trials that have adequately assessed optimal transfusion thresholds specifically among brain-injured patients. The importance of ischemia and the implications of anemia are not necessarily the same for all neurocritical care conditions. Nevertheless, there exists an extensive body of experimental work, as well as human observational and physiologic studies, which have advanced knowledge in this area and provide some guidance to clinicians. Lower hemoglobin concentrations are consistently associated with worse physiologic parameters and clinical outcomes; however, this relationship may not be altered by more aggressive use of red blood cell transfusions. Conclusions Although hemoglobin concentrations as low as 7 g/dl are well tolerated in most critical care patients, such a severe degree of anemia could be harmful in brain-injured patients. Randomized controlled trials of different transfusion thresholds, specifically in neurocritical care settings, are required. The impact of the duration of blood storage on the neurologic implications of transfusion also requires further investigation. PMID:19519893

  3. Red blood cell replacement, or nanobiotherapeutics with enhanced red blood cell functions?

    PubMed

    Chang, Thomas Ming Swi

    2015-06-01

    Why is this important? Under normal circumstances, donor blood is the best replacement for blood. However, there are exceptions: During natural epidemics (e.g., HIV, Ebola, etc.) or man-made epidemics (terrorism, war, etc.), there is a risk of donor blood being contaminated, and donors being disqualified because they have contracted disease. Unlike red blood cells (RBCs), blood substitutes can be sterilized to remove infective agents. Heart attack and stroke are usually caused by obstruction of arterial blood vessels. Unlike RBCs, which are particulate, blood substitutes are in the form of a solution that can perfuse through obstructed vessels with greater ease to reach the heart and brain, as has been demonstrated in animal studies. Severe blood loss from injuries sustained during accidents, disasters, or war may require urgent blood transfusion that cannot wait for transportation to the hospital for blood group testing. Unlike RBCs, blood substitutes do not have specific blood groups, and can be administered on the spot. RBCs have to be stored under refrigeration for up to 42 days, and are thus difficult to transport and store in times of disaster and at the battlefront. Blood substitutes can be stored at room temperature for more than 1 year, compared to the RBC shelf life of 1 day, at room temperature. In cases of very severe hemorrhagic shock, there is usually a safety window of 60 min for blood replacement, beyond which there could be problems related to irreversible shock. Animal studies show that a particular type of blood substitute, with enhanced RBC enzymes, may be able to prolong the duration of the safety window.

  4. Automated microscopy system for peripheral blood cells

    NASA Astrophysics Data System (ADS)

    Boev, Sergei F.; Sazonov, Vladimir V.; Kozinets, Gennady I.; Pogorelov, Valery M.; Gusev, Alexander A.; Korobova, Farida V.; Vinogradov, Alexander G.; Verdenskaya, Natalya V.; Ivanova, Irina A.

    2000-11-01

    The report describes the instrument ASPBS (Automated Screening of Peripheral Blood Cells) designed for an automated analysis of dry blood smears. The instrument is based on computer microscopy and uses dry blood smears prepared according to the standard Romanovskii-Giemza procedure. In comparison with the well-known flow cytometry systems, our instrument provides more detailed information and offers an opporunity of visualizing final results. The basic performances of the instrument are given. Software of this instrument is based on digital image processing and image recognition procedures. It is pointed out that the instrument can be used as a fairly universal tool in scientific research, public demonstrations, in medical treatment, and in medical education. The principle used as the basis of the instrument appeared adequate for creating an instrument version serviceable even during space flights where standard manual procedures and flow cytometry systems fail. The benefit of the use of the instrument in clinical laboratories is described.

  5. Pleomorphic Structures in Human Blood Are Red Blood Cell-Derived Microparticles, Not Bacteria

    PubMed Central

    Mitchell, Adam J.; Gray, Warren D.; Schroeder, Max; Yi, Hong; Taylor, Jeannette V.; Dillard, Rebecca S.; Ke, Zunlong; Wright, Elizabeth R.; Stephens, David; Roback, John D.; Searles, Charles D.

    2016-01-01

    Background Red blood cell (RBC) transfusions are a common, life-saving therapy for many patients, but they have also been associated with poor clinical outcomes. We identified unusual, pleomorphic structures in human RBC transfusion units by negative-stain electron microscopy that appeared identical to those previously reported to be bacteria in healthy human blood samples. The presence of viable, replicating bacteria in stored blood could explain poor outcomes in transfusion recipients and have major implications for transfusion medicine. Here, we investigated the possibility that these structures were bacteria. Results Flow cytometry, miRNA analysis, protein analysis, and additional electron microscopy studies strongly indicated that the pleomorphic structures in the supernatant of stored RBCs were RBC-derived microparticles (RMPs). Bacterial 16S rDNA PCR amplified from these samples were sequenced and was found to be highly similar to species that are known to commonly contaminate laboratory reagents. Conclusions These studies suggest that pleomorphic structures identified in human blood are RMPs and not bacteria, and they provide an example in which laboratory contaminants may can mislead investigators. PMID:27760197

  6. Pleomorphic Structures in Human Blood Are Red Blood Cell-Derived Microparticles, Not Bacteria.

    PubMed

    Mitchell, Adam J; Gray, Warren D; Schroeder, Max; Yi, Hong; Taylor, Jeannette V; Dillard, Rebecca S; Ke, Zunlong; Wright, Elizabeth R; Stephens, David; Roback, John D; Searles, Charles D

    2016-01-01

    Red blood cell (RBC) transfusions are a common, life-saving therapy for many patients, but they have also been associated with poor clinical outcomes. We identified unusual, pleomorphic structures in human RBC transfusion units by negative-stain electron microscopy that appeared identical to those previously reported to be bacteria in healthy human blood samples. The presence of viable, replicating bacteria in stored blood could explain poor outcomes in transfusion recipients and have major implications for transfusion medicine. Here, we investigated the possibility that these structures were bacteria. Flow cytometry, miRNA analysis, protein analysis, and additional electron microscopy studies strongly indicated that the pleomorphic structures in the supernatant of stored RBCs were RBC-derived microparticles (RMPs). Bacterial 16S rDNA PCR amplified from these samples were sequenced and was found to be highly similar to species that are known to commonly contaminate laboratory reagents. These studies suggest that pleomorphic structures identified in human blood are RMPs and not bacteria, and they provide an example in which laboratory contaminants may can mislead investigators.

  7. Hemodynamic effects of red blood cell aggregation.

    PubMed

    Baskurt, Oguz K; Meiselman, Herbert J

    2007-01-01

    The influence of red blood cell (RBC) aggregation on blood flow in vivo has been under debate since early 1900's, yet a full understanding has still has not been reached. Enhanced RBC aggregation is well known to increase blood viscosity measured in rotational viscometers. However, it has been demonstrated that RBC aggregation may decrease flow resistance in cylindrical tubes, due to the formation of a cell-poor zone near the tube wall which results from the enhanced central accumulation of RBC. There is also extensive discussion regarding the effects of RBC aggregation on in vivo blood flow resistance. Several groups have reported increased microcirculatory flow resistance with enhanced RBC aggregation in experiments that utilized intravital microscopy. Alternatively, whole organ studies revealed that flow resistance may be significantly decreased if RBC aggregation is enhanced. Recently, new techniques have been developed to achieve well-controlled, graded alterations in RBC aggregation without influencing suspending phase properties. Studies using this technique revealed that the effects of RBC aggregation are determined by the degree of aggregation changes, and that this relationship can be explained by different hemodynamic mechanisms.

  8. Understanding red blood cell alloimmunization triggers.

    PubMed

    Hendrickson, Jeanne E; Tormey, Christopher A

    2016-12-02

    Blood group alloimmunization is "triggered" when a person lacking a particular antigen is exposed to this antigen during transfusion or pregnancy. Although exposure to an antigen is necessary for alloimmunization to occur, it is not alone sufficient. Blood group antigens are diverse in structure, function, and immunogenicity. In addition to red blood cells (RBCs), a recipient of an RBC transfusion is exposed to donor plasma, white blood cells, and platelets; the potential contribution of these elements to RBC alloimmunization remains unclear. Much attention in recent years has been placed on recipient factors that influence RBC alloantibody responses. Danger signals, identified in murine and human studies alike as being risk factors for alloimmunization, may be quite diverse in nature. In addition to exogenous or condition-associated inflammation, autoimmunity is also a risk factor for alloantibody formation. Triggers for alloimmunization in pregnancy are not well-understood beyond the presence of a fetal/maternal bleed. Studies using animal models of pregnancy-induced RBC alloimmunization may provide insight in this regard. A better understanding of alloimmunization triggers and signatures of "responders" and "nonresponders" is needed for prevention strategies to be optimized. A common goal of such strategies is increased transfusion safety and improved pregnancy outcomes.

  9. Piezo1 links mechanical forces to red blood cell volume.

    PubMed

    Cahalan, Stuart M; Lukacs, Viktor; Ranade, Sanjeev S; Chien, Shu; Bandell, Michael; Patapoutian, Ardem

    2015-05-22

    Red blood cells (RBCs) experience significant mechanical forces while recirculating, but the consequences of these forces are not fully understood. Recent work has shown that gain-of-function mutations in mechanically activated Piezo1 cation channels are associated with the dehydrating RBC disease xerocytosis, implicating a role of mechanotransduction in RBC volume regulation. However, the mechanisms by which these mutations result in RBC dehydration are unknown. In this study, we show that RBCs exhibit robust calcium entry in response to mechanical stretch and that this entry is dependent on Piezo1 expression. Furthermore, RBCs from blood-cell-specific Piezo1 conditional knockout mice are overhydrated and exhibit increased fragility both in vitro and in vivo. Finally, we show that Yoda1, a chemical activator of Piezo1, causes calcium influx and subsequent dehydration of RBCs via downstream activation of the KCa3.1 Gardos channel, directly implicating Piezo1 signaling in RBC volume control. Therefore, mechanically activated Piezo1 plays an essential role in RBC volume homeostasis.

  10. Piezo1 links mechanical forces to red blood cell volume

    PubMed Central

    Cahalan, Stuart M; Lukacs, Viktor; Ranade, Sanjeev S; Chien, Shu; Bandell, Michael; Patapoutian, Ardem

    2015-01-01

    Red blood cells (RBCs) experience significant mechanical forces while recirculating, but the consequences of these forces are not fully understood. Recent work has shown that gain-of-function mutations in mechanically activated Piezo1 cation channels are associated with the dehydrating RBC disease xerocytosis, implicating a role of mechanotransduction in RBC volume regulation. However, the mechanisms by which these mutations result in RBC dehydration are unknown. In this study, we show that RBCs exhibit robust calcium entry in response to mechanical stretch and that this entry is dependent on Piezo1 expression. Furthermore, RBCs from blood-cell-specific Piezo1 conditional knockout mice are overhydrated and exhibit increased fragility both in vitro and in vivo. Finally, we show that Yoda1, a chemical activator of Piezo1, causes calcium influx and subsequent dehydration of RBCs via downstream activation of the KCa3.1 Gardos channel, directly implicating Piezo1 signaling in RBC volume control. Therefore, mechanically activated Piezo1 plays an essential role in RBC volume homeostasis. DOI: http://dx.doi.org/10.7554/eLife.07370.001 PMID:26001274

  11. [Peripheral blood hematopoietic stem cell collection].

    PubMed

    Bojanić, Ines; Mazić, Sanja; Cepulić, Branka Golubić

    2009-01-01

    Summary. Peripheral blood hematopoietic stem cells (PBSC) have numerous advatages in comparison with traditionally used bone marrow. PBSC collection by leukapheresis procedure is simpler and better tolerated than bone marrow harvest. PBCS are mobilized by myelosupressive chemotherapy or/and hematopoietic growth factors. Leukapheresis product contains PBSC along with lineage commited progenitors and precursors which contribute to faster hematopoietic recovery. In "poor mobilizers" options are large-volume leukapheresis (LVL) procedure or second generation of mobilising agents (pegfilgrastim, CXCR4 receptor antagonists). Total blood volume is processed 2-3 times in standard procedure compared to more than 3 times in LVL. LVL yields significantly higher numbers of CD34+ cells. Adverse effects of leukapheresis are electrolyte disbalance (hypocalcemia) caused by citrat administration and risk of bleeding due to trobocytopenia and heparin administration. PBSC collection and product quality control are regulated by national and international standards and recommendations.

  12. Acute psychological stress increases peripheral blood CD3+CD56+ natural killer T cells in healthy men: possible implications for the development and treatment of allergic and autoimmune disorders.

    PubMed

    Atanackovic, Djordje; Nowottne, Ulrike; Freier, Eva; Weber, Cora Stefanie; Meyer, Sabrina; Bartels, Katrin; Hildebrandt, York; Cao, Yanran; Kröger, Nicolaus; Brunner-Weinzierl, Monika Christine; Bokemeyer, Carsten; Deter, Hans-Christian

    2013-07-01

    Acute psychological stress has primarily been investigated regarding its effects on conventional lymphocytes such as natural killer (NK) cells and CD4(+) and CD8(+) T cells. However, it might be important to focus on more "specialized" lymphocyte subsets, playing a role, for instance, in allergic conditions and autoimmunity, to identify links between stress, the immune system and somatic diseases. Using flow cytometry we determined frequencies of circulating T helper (Th)1-type (CD226(+)) and Th2-type (CRTH2(+)) T cells, γδ T cells, conventional CD56(+) natural killer T (NKT) cells and invariant NKT cells (iNKT) in healthy young males (N = 31; median age 26 years) undergoing a laboratory computer-based stressor lasting 12 min. We found that acute psychological stress induced a prolonged increase in CD4(+) and CD8(+) T cells expressing a Th2 phenotype. We also detected an acute increase in CD4(-) and CD8(-) double negative γδ T cells. Finally, we found that the well-known increase in NK cells under stressful conditions was paralleled by a significant increase in numbers of conventional CD56(+) NKT cells. In contrast, numbers of iNKT was not altered by stress. This study adds further evidence to a psychoneuroimmunological model proposing that under stressful conditions certain lymphocyte subsets, including iNKT and less mature T cells, are retained in lymphoid tissues while antigen-experienced effector-type T cells with a Th2 phenotype, γδ T cells and conventional CD56(+) NKT cells are mobilized into the peripheral blood. We suggest that in the case of frequent stress exposure, this might result in the promotion of, for example, allergic conditions.

  13. Surface Enhanced Raman Scattering of Whole Human Blood, Blood Plasma and Red Blood Cells: Cellular Processes and Bioanalytical Sensing

    PubMed Central

    Premasiri, W. R.; Lee, J. C.; Ziegler, L. D.

    2013-01-01

    SERS spectra of whole human blood, blood plasma and red blood cells on Au nanoparticle SiO2 substrates excited at 785 nm have been observed. For the sample preparation procedure employed here, the SERS spectrum of whole blood arises from the blood plasma component only. This is in contrast to the normal Raman spectrum of whole blood excited at 785 nm and open to ambient air, which is exclusively due to the scattering of oxyhemoglobin. The SERS spectrum of whole blood shows a storage time dependence that is not evident in the non-SERS Raman spectrum of whole blood. Hypoxanthine, a product of purine degradation, dominates the SERS spectrum of blood after ~10 – 20 hours of storage at 8 °C. The corresponding SERS spectrum of plasma isolated from the stored blood shows the same temporal release of hypoxanthine. Thus, blood cellular components (red blood cells, white blood cells and/or platelets) are releasing hypoxanthine into the plasma over this time interval. The SERS spectrum of red blood cells (RBCs) excited at 785 nm is reported for the first time and exhibits well known heme group marker bands, as well as other bands that may be attributed to cell membrane components or protein denaturation contributions. SERS, as well as normal Raman spectra, of oxy- and met-RBCs are reported and compared. These SERS results can have significant impact in the area of clinical diagnostics, blood supply management and forensics. PMID:22780445

  14. Freeze-Dried Human Red Blood Cells

    DTIC Science & Technology

    1992-04-15

    chromium labelled mRBC via an intravenous catheter in the peripheral saphenous vein . Following administration of labelled mRBC into each monkey, 0.2ml...with a single dose of autologous , lyophilized and reconstituted, 5 1Cr-labelled packed erythrocytes via an intravenous catheter in a peripheral vein ...study site, at which time a 25 ml aliquot of reconstituted 51-Cr labeled autologous red blood cells will be infused intravenously into a large arm vein

  15. Freeze-Dried Human Red Blood Cells

    DTIC Science & Technology

    1991-07-12

    cells with 5 1Cr sodium chromate, collection of urine and peripheral blood samples, 5 1Cr organ uptake, whole body gamma imaging, and calculation of whole...7. Subject does not have a history of: - Renal disorders or BUN, creatinine, uric acid, sodium , potassium or chloride values outside the...uric acid, calcium, inorganic phosphorus, glucose, sodium , potassium, chloride, bicarbonate. Coagulation: prothrombin time (subject and control) and

  16. Stem-cell therapies for blood diseases

    NASA Astrophysics Data System (ADS)

    Bordignon, Claudio

    2006-06-01

    For decades, transplantation of haematopoietic stem cells - either unmodified, or genetically modified to correct genetic disorders - has been used to treat disorders of the blood and immune systems. The present challenge is to reduce the risk of such transplants and increase the number of patients who can safely access this treatment. In developing countries, such `one-shot' treatments are highly desirable because chronic treatments are difficult to sustain. To make these therapies more accessible and effective it will be important to improve clinical protocols and gene-delivery vectors, and to gain a deeper understanding of stem cells.

  17. [Clinical use of haematopoietic stem cells from cord blood].

    PubMed

    Lyngstadaas, Anita; Husebekk, Anne; Funderud, Steinar; Brinch, Lorentz

    2004-11-18

    A group of experts appointed by the Norwegian Centre for Health Technology Assessment (SMM) has undertaken a systematic review of available literature on the clinical effectiveness of transplanting haematopoietic stem cells from cord blood. A total of 17 studies form the documentary basis of the review. Autologous transplants of stem cells from cord blood have not been published. Retrospective studies suggest that the clinical effect of allogeneic cord blood transplants, at least in children, is comparable to transplants with allogeneic stem cells from bone marrow or peripheral blood cells. This review demonstrates the need for prospective studies comparing transplantations of cord blood with bone marrow or peripheral blood stem cells.

  18. Microconfined flow behavior of red blood cells.

    PubMed

    Tomaiuolo, Giovanna; Lanotte, Luca; D'Apolito, Rosa; Cassinese, Antonio; Guido, Stefano

    2016-01-01

    Red blood cells (RBCs) perform essential functions in human body, such as gas exchange between blood and tissues, thanks to their ability to deform and flow in the microvascular network. The high RBC deformability is mainly due to the viscoelastic properties of the cell membrane. Since an impaired RBC deformability could be found in some diseases, such as malaria, sickle cell anemia, diabetes and hereditary disorders, there is the need to provide further insight into measurement of RBC deformability in a physiologically relevant flow field. Here, RBCs deformability has been studied in terms of the minimum apparent plasma-layer thickness by using high-speed video microscopy of RBCs flowing in cylindrical glass capillaries. An in vitro systematic microfluidic investigation of RBCs in micro-confined conditions has been performed, resulting in the determination of the RBCs time recovery constant, RBC volume and surface area and RBC membrane shear elastic modulus and surface viscosity. It has been noticed that the deformability of RBCs induces cells aggregation during flow in microcapillaries, allowing the formation of clusters of cells. Overall, our results provide a novel technique to estimate RBC deformability and also RBCs collective behavior, which can be used for the analysis of pathological RBCs, for which reliable quantitative methods are still lacking.

  19. Superior long-term repopulating capacity of G-CSF+plerixafor-mobilized blood: implications for stem cell gene therapy by studies in the Hbb(th-3) mouse model.

    PubMed

    Psatha, Nikoleta; Sgouramali, Eleni; Gkountis, Antonios; Siametis, Athanasios; Baliakas, Panayotis; Constantinou, Varnavas; Athanasiou, Evangelia; Arsenakis, Minas; Anagnostopoulos, Achilles; Papayannopoulou, Thalia; Stamatoyannopoulos, George; Yannaki, Evangelia

    2014-12-01

    High numbers of genetically modified hematopoietic stem cells (HSCs) equipped with enhanced engrafting potential are required for successful stem cell gene therapy. By using thalassemia as a model, we investigated the functional properties of hematopoietic stem and progenitor cells (HSPCs) from Hbb(th3)/45.2(+) mice after mobilization with G-CSF, plerixafor, or G-CSF+plerixafor and the engraftment kinetics of primed cells after competitive primary and noncompetitive secondary transplantation. G-CSF+plerixafor yielded the highest numbers of HSPCs, while G-CSF+plerixafor-mobilized Hbb(th3)/45.2(+) cells, either unmanipulated or transduced with a reporter vector, achieved faster hematologic reconstitution and higher levels of donor chimerism over all other types of mobilized cells, after competitive transplantation to B6.BoyJ/45.1(+) recipients. The engraftment benefit observed in the G-CSF+plerixafor group was attributed to the more primitive stem cell phenotype of G-CSF+plerixafor-LSK cells, characterized by higher CD150(+)/CD48 expression. Moreover, secondary G-CSF+plerixafor recipients displayed stable or even higher chimerism levels as compared with primary engrafted mice, thus maintaining or further improving engraftment levels over G-CSF- or plerixafor-secondary recipients. Plerixafor-primed cells displayed the lowest competiveness over all other mobilized cells after primary or secondary transplantation, probably because of the higher frequency of more actively proliferating LK cells. Overall, the higher HSC yields, the faster hematological recovery, and the superiority in long-term engraftment indicate G-CSF+plerixafor-mobilized blood as an optimal graft source, not only for thalassemia gene therapy, but also for stem cell gene therapy applications in general.

  20. Mechanosensing Dynamics of Red blood Cells

    NASA Astrophysics Data System (ADS)

    Wan, Jiandi

    2015-11-01

    Mechanical stress-induced deformation of human red blood cells (RBCs) plays important physiopathological roles in oxygen delivery, blood rheology, transfusion, and malaria. Recent studies demonstrate that, in response to mechanical deformation, RBCs release adenosine-5'-triphosphate (ATP), suggesting the existence of mechanotransductive pathways in RBCs. Most importantly, the released ATP from RBCs regulates vascular tone and impaired release of ATP from RBCs has been linked to diseases such as type II diabetes and cystic fibrosis. To date, however, the mechanisms of mechanotransductive release of ATP from RBCs remain unclear. Given that RBCs experience shear stresses continuously during the circulation cycle and the released ATP plays a central role in vascular physiopathology, understanding the mechanotransductive release of ATP from RBCs will provide not only fundamental insights to the role of RBCs in vascular homeostasis but also novel therapeutic strategies for red cell dysfunction and vascular disease. This talk describes the main research in my group on integrating microfluidic-based approaches to study the mechanosensing dynamics of RBCs. Specifically, I will introduce a micro?uidic approach that can probe the dynamics of shear-induced ATP release from RBCs with millisecond resolution and provide quantitative understandings of the mechanosensitive ATP release processes in RBCs. Furthermore, I will also describe our recent findings about the roles of the Piezo1 channel, a newly discovered mechanosensitive cation channel in the mechanotransductive ATP release in RBCs. Last, possible functions of RBCs in the regulation of cerebral blood flow will be discussed.

  1. 21 CFR 660.30 - Reagent Red Blood Cells.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 7 2011-04-01 2010-04-01 true Reagent Red Blood Cells. 660.30 Section 660.30 Food... ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.30 Reagent Red Blood Cells. (a) Proper name and definition. The proper name of the product shall be Reagent...

  2. 21 CFR 660.30 - Reagent Red Blood Cells.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Reagent Red Blood Cells. 660.30 Section 660.30...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.30 Reagent Red Blood Cells. (a) Proper name and definition. The proper name of the product shall...

  3. Deterministic Migration-Based Separation of White Blood Cells.

    PubMed

    Kim, Byeongyeon; Choi, Young Joon; Seo, Hyekyung; Shin, Eui-Cheol; Choi, Sungyoung

    2016-10-01

    Functional and phenotypic analyses of peripheral white blood cells provide useful clinical information. However, separation of white blood cells from peripheral blood requires a time-consuming, inconvenient process and thus analyses of separated white blood cells are limited in clinical settings. To overcome this limitation, a microfluidic separation platform is developed to enable deterministic migration of white blood cells, directing the cells into designated positions according to a ridge pattern. The platform uses slant ridge structures on the channel top to induce the deterministic migration, which allows efficient and high-throughput separation of white blood cells from unprocessed whole blood. The extent of the deterministic migration under various rheological conditions is explored, enabling highly efficient migration of white blood cells in whole blood and achieving high-throughput separation of the cells (processing 1 mL of whole blood less than 7 min). In the separated cell population, the composition of lymphocyte subpopulations is well preserved, and T cells secrete cytokines without any functional impairment. On the basis of the results, this microfluidic platform is a promising tool for the rapid enrichment of white blood cells, and it is useful for functional and phenotypic analyses of peripheral white blood cells. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. 21 CFR 660.30 - Reagent Red Blood Cells.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 7 2012-04-01 2012-04-01 false Reagent Red Blood Cells. 660.30 Section 660.30...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.30 Reagent Red Blood Cells. (a) Proper name and definition. The proper name of the product shall...

  5. 21 CFR 660.30 - Reagent Red Blood Cells.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 7 2014-04-01 2014-04-01 false Reagent Red Blood Cells. 660.30 Section 660.30...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.30 Reagent Red Blood Cells. (a) Proper name and definition. The proper name of the product shall...

  6. 21 CFR 660.30 - Reagent Red Blood Cells.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 7 2013-04-01 2013-04-01 false Reagent Red Blood Cells. 660.30 Section 660.30...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.30 Reagent Red Blood Cells. (a) Proper name and definition. The proper name of the product shall...

  7. 21 CFR 864.5240 - Automated blood cell diluting apparatus.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Automated blood cell diluting apparatus. 864.5240 Section 864.5240 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... § 864.5240 Automated blood cell diluting apparatus. (a) Identification. An automated blood cell diluting...

  8. 21 CFR 864.7100 - Red blood cell enzyme assay.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Red blood cell enzyme assay. 864.7100 Section 864...) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7100 Red blood cell enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in...

  9. 21 CFR 864.7100 - Red blood cell enzyme assay.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Red blood cell enzyme assay. 864.7100 Section 864...) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7100 Red blood cell enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in...

  10. 21 CFR 864.5240 - Automated blood cell diluting apparatus.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Automated blood cell diluting apparatus. 864.5240 Section 864.5240 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... § 864.5240 Automated blood cell diluting apparatus. (a) Identification. An automated blood cell diluting...

  11. 21 CFR 864.7100 - Red blood cell enzyme assay.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Red blood cell enzyme assay. 864.7100 Section 864...) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7100 Red blood cell enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in...

  12. 21 CFR 864.7100 - Red blood cell enzyme assay.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Red blood cell enzyme assay. 864.7100 Section 864...) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7100 Red blood cell enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in...

  13. 21 CFR 864.5240 - Automated blood cell diluting apparatus.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Automated blood cell diluting apparatus. 864.5240 Section 864.5240 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... § 864.5240 Automated blood cell diluting apparatus. (a) Identification. An automated blood cell diluting...

  14. 21 CFR 864.5240 - Automated blood cell diluting apparatus.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Automated blood cell diluting apparatus. 864.5240 Section 864.5240 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... § 864.5240 Automated blood cell diluting apparatus. (a) Identification. An automated blood cell diluting...

  15. Cryopreservation of Autologous Blood (Red Blood Cells, Platelets and Plasma)

    NASA Astrophysics Data System (ADS)

    Ebine, Kunio

    Prevention of post-transfusion hepatitis is still a problem in cardiovascular surgery. We initiated the cryopreservation of autologous blood for the transfusion in elective cardiovascular surgery since 1981. This study includes 152 surgical cases in which autologous frozen, allogeneic frozen, and/or allogeneic non-frozen blood were used. In the 152 surgical cases, there were 69 cases in which autologous blood only (Group I) was used; 12 cases with autologous and allogeneic frozen blood (Group II); 46 cases with autologous and allgeneic frozen plus allogeneic non-frozen blood (Group III); and 25 cases with allogeneic frozen plus allogeneic non-frozen blood (Group IV). No hepatitis developed in Groups I (0%) and II (0%), but there was positive hepatitis in Groups III (4.3%) and IV (8.0%) . In 357 cases of those who underwent surgery with allogeneic non-frozen whole blood during the same period, the incidence rate of hepatitis was 13.7% (49/357). Patients awaiting elective surgery can store their own blood in the frozen state. Patients who undergo surgery with the cryoautotransfusion will not produce any infections or immunologic reactions as opposed to those who undergo surgery with the allogeneic non-frozen blood.

  16. Red blood cell nitric oxide synthase modulates red blood cell deformability in sickle cell anemia.

    PubMed

    Mozar, Anaïs; Connes, Philippe; Collins, Bianca; Hardy-Dessources, Marie-Dominique; Romana, Marc; Lemonne, Nathalie; Bloch, Wilhelm; Grau, Marijke

    2016-11-04

    Sickle cell anemia (SCA) is an inherited red blood cells (RBC) disorder characterized by significantly decreased RBC deformability. The present study aimed to assess whether modulation of RBC Nitric Oxide Synthase (RBC-NOS) activation could affect RBC deformability in SCA.Blood of twenty-five SCA patients was treated for 1 hour at 37°C with Phosphate Buffered Saline (PBS) or PBS containing 1% of Dimethylsulfoxyde as control, L-arginine or N(5)-(1-Iminoethyl)-L-ornithine (L-NIO) to directly stimulate or inhibit RBC-NOS, insulin or wortmannin to indirectly stimulate or inhibit RBC-NOS through their effects on the PI3 Kinase/Akt pathway, and sodium nitroprusside (SNP) and 2-(4-Carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (cPTIO) as NO donor and NO scavenger, respectively. RBC deformability was measured by ektacytometry at 3 Pa.RBC deformability significantly increased after insulin treatment and significantly decreased after L-NIO and wortmannin incubation. The other conditions did not affect deformability. Significantly increased nitrotyrosine levels, a marker of enhanced free radical generation, were detected by immunohistochemistry in SNP and insulin treated samples.These data suggest that RBC deformability of SCA can be modulated by RBC-NOS activity but also that oxidative stress may impair effectiveness of RBC-NOS produced NO.

  17. Red Blood Cell Count Automation Using Microscopic Hyperspectral Imaging Technology.

    PubMed

    Li, Qingli; Zhou, Mei; Liu, Hongying; Wang, Yiting; Guo, Fangmin

    2015-12-01

    Red blood cell counts have been proven to be one of the most frequently performed blood tests and are valuable for early diagnosis of some diseases. This paper describes an automated red blood cell counting method based on microscopic hyperspectral imaging technology. Unlike the light microscopy-based red blood count methods, a combined spatial and spectral algorithm is proposed to identify red blood cells by integrating active contour models and automated two-dimensional k-means with spectral angle mapper algorithm. Experimental results show that the proposed algorithm has better performance than spatial based algorithm because the new algorithm can jointly use the spatial and spectral information of blood cells.

  18. Optical analysis of red blood cell suspension

    NASA Astrophysics Data System (ADS)

    Szołna, Alicja A.; Grzegorzewski, Bronisław

    2008-12-01

    The optical properties of suspensions of red blood cells (RBCs) were studied. Fresh human venues blood was obtained from adult healthy donors. RBCs were suspended in isotonic salt solution, and in autologous plasma. Suspensions with haematocrit 0.25 - 3% were investigated. Novel technique was proposed to determine the scattering coefficient μs for the suspensions. The intensity of He-Ne laser light transmitted through a wedge-shape container filled with a suspension was recorded. To find the dependence of the intensity on the thickness of the sample the container was moved horizontally. The dependence of μs on the haematocrit was determined for RBCs suspended in the isotonic salt solution. RBCs suspended in plasma tend to form rouleaux. For the RBCs suspended in plasma, the scattering coefficient as a function of time was obtained. It is shown that this technique can be useful in the study of rouleaux formation.

  19. Multiscale modeling of blood flow: from single cells to blood rheology.

    PubMed

    Fedosov, Dmitry A; Noguchi, Hiroshi; Gompper, Gerhard

    2014-04-01

    Mesoscale simulations of blood flow, where the red blood cells are described as deformable closed shells with a membrane characterized by bending rigidity and stretching elasticity, have made much progress in recent years to predict the flow behavior of blood cells and other components in various flows. To numerically investigate blood flow and blood-related processes in complex geometries, a highly efficient simulation technique for the plasma and solutes is essential. In this review, we focus on the behavior of single and several cells in shear and microcapillary flows, the shear-thinning behavior of blood and its relation to the blood cell structure and interactions, margination of white blood cells and platelets, and modeling hematologic diseases and disorders. Comparisons of the simulation predictions with existing experimental results are made whenever possible, and generally very satisfactory agreement is obtained.

  20. Kit for the selective labeling of red blood cells in whole blood with [sup 99]Tc

    DOEpatents

    Srivastava, S.C.; Babich, J.W.; Straub, R.; Richards, P.

    1992-05-26

    Disclosed herein are a method and kit for the preparation of [sup 99m]Tc labeled red blood cells using whole blood in a closed sterile system containing stannous tin in a form such that it will enter the red blood cells and be available therein for reduction of technetium. No Drawings

  1. Kit for the selective labeling of red blood cells in whole blood with .sup.9 TC

    DOEpatents

    Srivastava, Suresh C.; Babich, John W.; Straub, Rita; Richards, Powell

    1992-01-01

    Disclosed herein are a method and kit for the preparation of .sup.99m Tc labeled red blood cells using whole blood in a closed sterile system containing stannous tin in a form such that it will enter the red blood cells and be available therein for reduction of technetium.

  2. Fresh Whole Blood Transfusion: Military and Civilian Implications.

    PubMed

    Goforth, Carl W; Tranberg, John W; Boyer, Phillip; Silvestri, Peter J

    2016-06-01

    Uncontrolled hemorrhage and exsanguination are the leading cause of preventable death, and resuscitative therapy is a critical component for survival. In various combinations, fresh whole blood, blood components, colloids, and crystalloids have all been staples of trauma care. The use of fresh whole blood is a well-established military practice that has saved the lives of thousands of American and coalition military personnel. Civilian use of fresh whole blood is far less established owing to the wide availability of individual blood components. However, this highly tailored blood supply is vulnerable to both natural and man-made disasters. In the event of such disruption, such as a major hurricane, it may be necessary for civilian hospitals to rapidly enact a fresh whole blood program. Therefore, the aim of this article is to review the current use of blood therapy for trauma resuscitation, the US military's approach to fresh whole blood, and how maintaining a civilian capacity for fresh whole blood collection in the event of future man-made and natural disasters is key to promoting survival from trauma. ©2016 American Association of Critical-Care Nurses.

  3. Colon cancer stem cells: implications in carcinogenesis

    PubMed Central

    Sanders, Matthew A.; Majumdar, Adhip P. N.

    2014-01-01

    The cancer stem cell model was described for hematologic malignancies in 1997 and since then evidence has emerged to support it for many solid tumors as well, including colon cancer. This model proposes that certain cells within the tumor mass are pluripotent and capable of self-renewal and have an enhanced ability to initiate distant metastasis. The cancer stem cell model has important implications for cancer treatment, since most current therapies target actively proliferating cells and may not be effective against the cancer stem cells that are responsible for recurrence. In recent years great progress has been made in identifying markers of both normal and malignant colon stem cells. Proteins proposed as colon cancer stem cell markers include CD133, CD44, CD166, ALDH1A1, Lgr5, and several others. In this review we consider the evidence for these proteins as colon cancer stem cell markers and as prognostic indicators of colon cancer survival. Additionally, we discuss potential functions of these proteins and the implications this may have for development of therapies that target colon cancer stem cells. PMID:21196254

  4. Therapeutic implications of Cancer Initiating Cells.

    PubMed

    Scopelliti, Alessandro; Cammareri, Patrizia; Catalano, Veronica; Saladino, Vitanna; Todaro, Matilde; Stassi, Giorgio

    2009-08-01

    Until few years ago, all neoplastic cells within a tumour were suggested to have tumorigenic capacity, but recent evidences hint to the possibility that such feature is confined to a subset of Cancer Initiating Cells (CICs), also called Cancer Stem Cells (CSCs). These cells are the reservoir of the heterogeneous populations of differentiated cancer cells constituting the tumour bulk. Mechanisms shared with somatic stem cells, such as quiescence, self-renewal ability, asymmetric division and multidrug resistance, allow to these cells to drive tumour growth and to evade conventional therapy. Here, we give a brief overview on the origin of CICs, the mechanisms involved in chemoresistance and therapeutic implications. Current cancer treatments, based on the assumption that tumour cell population responds homogeneously, have been developed to eradicate proliferating cells. The new model of tumorigenesis entails significant therapeutic implications, in fact if a small fraction of CICs survives conventional therapy it may lead to recurrence after month or years of apparent remission. Selective targeting of CICs could eliminate the tumour from the root, overcoming the emergence of clones capable of evading traditional therapy and increasing overall disease free survival.

  5. Peripheral blood stem cell transplant-related Plasmodium falciparum infection in a patient with sickle cell disease.

    PubMed

    Mejia, Rojelio; Booth, Garrett S; Fedorko, Daniel P; Hsieh, Matthew M; Khuu, Hanh M; Klein, Harvey G; Mu, Jianbing; Fahle, Gary; Nutman, Thomas B; Su, Xin-Zhuan; Williams, Esther C; Flegel, Willy A; Klion, Amy

    2012-12-01

    Although transmission of Plasmodium falciparum (Pf) infection during red blood cell (RBC) transfusion from an infected donor has been well documented, malaria parasites are not known to infect hematopoietic stem cells. We report a case of Pf infection in a patient 11 days after peripheral blood stem cell transplant for sickle cell disease. Malaria parasites were detected in thick blood smears by Giemsa staining. Pf HRP2 antigen was measured by enzyme-linked immunosorbent assay on whole blood and plasma. Pf DNA was detected in whole blood and stem cell retention samples by real-time polymerase chain reaction using Pf species-specific primers and probes. Genotyping of eight Pf microsatellites was performed on genomic DNA extracted from whole blood. Pf was not detected by molecular, serologic, or parasitologic means in samples from the recipient until Day 11 posttransplant, coincident with the onset of symptoms. In contrast, Pf antigen was retrospectively detected in stored plasma collected 3 months before transplant from the asymptomatic donor. Pf DNA was detected in whole blood from both the donor and the recipient after transplant, and genotyping confirmed shared markers between donor and recipient Pf strains. Lookback analysis of RBC donors was negative for Pf infection. These findings are consistent with transmission by the stem cell product and have profound implications with respect to the screening of potential stem cell donors and recipients from malaria-endemic regions. © 2012 American Association of Blood Banks.

  6. The flow of red blood cells in stenosed microvessels and the influence of red blood cells on wall-bounded rolling motion of microparticles

    NASA Astrophysics Data System (ADS)

    Vahidkhah, Koohyar; Balogh, Peter; Bagchi, Prosenjit

    2015-11-01

    In the first part of this work, we consider a 3D computational study of the flow of deformable red blood cells in stenosed microvessels. We observe that the apparent viscosity of blood increases by several folds, and the rate of increase with increasing vessel diameter is also higher than that in non-stenosed vessels, implying an enhancement of the well-known Fahraeus-Lindqvist effect. The flow of the red blood cells causes time-dependent fluctuations in the blood flow rate. The RMS of the flow rate oscillations in the stenosed vessel is observed to be significantly higher than that in the non-stenosed vessel. Furthermore, several folds increase in the Eulerian velocity fluctuations and a transient flow reversal upstream the stenosed region are also observed, which would not occur in absence of the cells. In the second part, we consider the adhesive rolling motion of wall-bounded microparticles in presence of flowing red blood cells in microvessels. We observe two contradictory role of the red blood cells: On one hand, the cells facilitate the establishment of the particle-wall contact, and, thereby, initiation of adhesion. On the other hand, they augment the rolling velocity of the particles. Implications of these results on the optimal design of drug carriers are discussed.

  7. Delayed clamping of the umbilical cord after delivery and implications for public cord blood banking.

    PubMed

    Allan, David S; Scrivens, Nicholas; Lawless, Tiffany; Mostert, Karen; Oppenheimer, Lawrence; Walker, Mark; Petraszko, Tanya; Elmoazzen, Heidi

    2016-03-01

    Public banking of umbilical cord blood units (CBUs) containing higher numbers of cells ensures timely engraftment after transplantation for increasing numbers of patients. Delayed clamping of the umbilical cord after birth may benefit some infants by preventing iron deficiency. Implications of delayed cord clamping for public cord blood banking remains unclear. CBUs collected by Canadian Blood Services at one collection site between November 1, 2014, and March 17, 2015, were analyzed. The delay in cord clamping after birth was timed and classified as "no delay," 20 to 60 seconds, more than 60 seconds, or more than 120 seconds. Of 367 collections, 100 reported no delay in clamping while clamping was delayed by 20 to 60 seconds (n = 69), more than 60 seconds (n = 98), or more than 120 seconds (n = 100) in the remaining cases. The mean volume and total nucleated cells (TNCs) in units with no delay in clamping were significantly greater than mean volumes for all categories of delayed clamping (Tukey's test, p < 0.05 for each comparison). The proportion of units with more than 1.5 × 10(9) TNCs was significantly reduced when clamping was delayed (p = 5.5 × 10(-8) ). The difference was most marked for cords that were clamped more than 120 seconds after delivery (6.2% compared with 39%). Delayed cord clamping greatly diminishes the volume and TNC count of units collected for a public cord blood bank. Creating an inventory of CBUs with high TNC content may take more time than expected. © 2015 AABB.

  8. Blood

    MedlinePlus

    ... spans vary from a few days to months. New cells are constantly being formed in the bone marrow. ... the bloodstream and are constantly being replaced by new cells. Blood also contains important proteins called clotting factors , ...

  9. Implications of Dengue Outbreaks for Blood Supply, Australia

    PubMed Central

    Seed, Clive R.; Fryk, Jesse J.; Hyland, Catherine A.; Ritchie, Scott A.; Taylor, Carmel T.; Van Der Merwe, Kathryn L.; Flower, Robert L.P.; McBride, William J.H.

    2013-01-01

    Dengue outbreaks have increased in size and frequency in Australia, and transfusion-transmitted dengue poses a risk to transfusion safety. Using whole blood samples collected during the large 2008–2009 dengue epidemic, we estimated the risk for a dengue-infectious blood donation as ≈1 in 7,146 (range 2,218–50,021). PMID:23648012

  10. Red Blood Cell Supernatant Potentiates LPS-Induced Proinflammatory Cytokine Response From Peripheral Blood Mononuclear Cells

    PubMed Central

    Nydam, Trevor L.; Clarke, Jason H.; Banerjee, Anirban; Silliman, Christopher C.; McCarter, Martin D.

    2009-01-01

    Allogeneic blood transfusion has an immunomodulatory capacity on its recipients through accumulation of immunologically active substances with blood storage, and prestorage leukoreduction reduces many of these mediators. We investigated lipopolysaccharide (LPS)-induced cytokine response of peripheral blood mononuclear cells (PBMCs) exposed to packed red blood cell (PRBC) supernatants from leukoreduced (LR) or non-leukoreduced (NLR) units with variable duration of storage. PRBC units were collected with or without leukoreduction on Day 0 before routine storage. The plasma fraction (supernatant) was isolated from LR and NLR units after 1 day (D1) or 42 days (D42) of storage and exposed to PBMCs versus control media for 24 h, then with LPS for an additional 24 h. Cell supernatants were analyzed for IL-1β, IL-6, IL-8, IL-10, and TNF-α by cytokine bead array. IL-1β, TNF-α, and IL-6 were significantly elevated in PRBC groups versus control. D42 NLR PRBC supernatant significantly increased secretion of IL-1β and IL-6 compared to D1 NLR PRBC supernatant. LR significantly attenuated the cytokine response of IL-1β. Thus, PRBC supernatant potentiates proinflammatory LPS-induced cytokine secretion from PBMCs. This response is accentuated with storage duration and partially attenuated with leukoreduction. These findings may partially explain the immune activation seen clinically after blood transfusion. PMID:19441884

  11. Red blood cell storage duration and trauma.

    PubMed

    Sparrow, Rosemary L

    2015-04-01

    Numerous retrospective clinical studies suggest that transfusion of longer stored red blood cells (RBCs) is associated with an independent risk of poorer outcomes for certain groups of patients, including trauma, intensive care, and cardiac surgery patients. Large multicenter randomized controlled trials are currently underway to address the concern about RBC storage duration. However, none of these randomized controlled trials focus specifically on trauma patients with hemorrhage. Major trauma, particularly due to road accidents, is the leading cause of critical injury in the younger-than-40-year-old age group. Severe bleeding associated with major trauma induces hemodynamic dysregulation that increases the risk of hypoxia, coagulopathy, and potentially multiorgan failure, which can be fatal. In major trauma, a multitude of stress-associated changes occur to the patient's RBCs, including morphological changes that increase cell rigidity and thereby alter blood flow hemodynamics, particularly in the microvascular vessels, and reduce RBC survival. Initial inflammatory responses induce deleterious cellular interactions, including endothelial activation, RBC adhesion, and erythrophagocytosis that are quickly followed by profound immunosuppressive responses. Stored RBCs exhibit similar biophysical characteristics to those of trauma-stressed RBCs. Whether transfusion of RBCs that exhibit storage lesion changes exacerbates the hemodynamic perturbations already active in the trauma patient is not known. This article reviews findings from several recent nonrandomized studies examining RBC storage duration and clinical outcomes in trauma patients. The rationale for further research on RBC storage duration in the trauma setting is provided. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Human red blood cell aging: correlative changes in surface charge and cell properties.

    PubMed

    Huang, Yao-Xiong; Wu, Zheng-Jie; Mehrishi, Jitendra; Huang, Bao-Tian; Chen, Xing-Yao; Zheng, Xin-Jing; Liu, Wen-Jing; Luo, Man

    2011-12-01

    Red blood cells (RBCs) during microcirculation, aging and storage, lose N-acetylneuraminic acid (NANA) and other biomaterials thereby altering cell structures, some properties and functions. Such cell damage very likely underlies the serious adverse effects of blood transfusion. However, a controversy has remained since 1961-1977 as to whether with aging, the RBCs, suffering loss of NANA, do have a decreased charge density. Any correlation between the changes in the cell properties with cell aging is also not clear. Therefore, to remove the ambiguity and uncertainty, we carried out multiparameteric studies on Percoll fractions of blood of 38 volunteers (lightest-young-Y-RBCs, densest-old-O-RBCs, two middle fractions).We found that there were striking differences between the properties of Y-RBCs and O-RBCs. The ζ-potential of Y-RBCs decreased gradually with aging. Studies in parallel on RBC fractions incubated with both positively charged quantum dots and Sambucus Nigra-fluorescein isothiocyanate (FITC) along with their ζ-potentials provide for the first time direct visual evidence about the lesser amount of charge density and NANA on O-RBCs, and a collinear decrease in their respective ζ-potentials. Close correlation was found between the surface charge on an aging RBC and its structure and functions, from the cell morphology, the membrane deformability to the intracellular Hb structure and oxidation ability. This quantitative approach not only clarifies the picture but also has implications in biology and medicine.

  13. Deformability of red blood cells and its relation to blood trauma in rotary blood pumps.

    PubMed

    Watanabe, Nobuo; Sakota, Daisuke; Ohuchi, Katsuhiro; Takatani, Setsuo

    2007-05-01

    In this study, mechanical trauma to red blood cells was evaluated by conventional hemolysis test and a newly developed cyclically reversing shear flow generator. The fresh porcine blood obtained from a local slaughterhouse was subjected to the conventional hemolysis test using a commercial centrifugal blood pump for the duration of 8 h. The measurements consisted of (i) plasma-free hemoglobin based on the standard optical measurement and (ii) the deformability of red blood cells (RBCs) using a cyclically reversing shear flow generator and microscope image acquisition system. The deformability of RBCs was expressed by the L/W value where L and W were the longer and shorter axes of the elongated RBCs' images. Although the plasma-free hemoglobin level increased with the pumping duration, the L/W remained unchanged for the duration of 8 h of pumping to indicate no alteration in the deformability. It was speculated that (i) although RBCs might have been circulated for so many times through the test pump, after each exposure to mechanical stress, RBCs might have recovered, and net effect due to shear stress-exposure time might have been small; and (ii) RBCs' deformability might be maintained near normal until sudden burst or membrane rupture, or the hemoglobin might have continuously leaked through the pores of the thinned membrane created by the mechanical stress. The deformability testing under a fluctuating shear flow could be a new method to quantify subhemolytic mechanical damage that has been accumulated in the RBCs' membrane and that may not be assessed by the conventional hemolysis test.

  14. Direct In Vivo Electrochemical Detection of Haemoglobin in Red Blood Cells

    NASA Astrophysics Data System (ADS)

    Toh, Rou Jun; Peng, Weng Kung; Han, Jongyoon; Pumera, Martin

    2014-08-01

    The electrochemical behavior of iron ion in haemoglobin provides insight to the chemical activity in the red blood cell which is important in the field of hematology. Herein, the detection of haemoglobin in human red blood cells on glassy carbon electrode (GC) was demonstrated. Red blood cells or raw blood cells was immobilized on a glassy carbon electrode surface with Nafion films employed to sandwich the layer of biological sample firmly on the electrode surface. Cyclic voltammetry (CV) analyses revealed a well-defined reduction peak for haemoglobin at about -0.30 V (vs. Ag/AgCl) at the red blood cell (GC-Nf-RBC-3Nf) and blood (GC-Nf-B-3Nf) film modified GCE in a pH 3.5 phosphate buffer solution. We further demonstrated that the complex biological conditions of a human red blood cell displayed no interference with the detection of haemoglobin. Such findings shall have an implication on the possibilities of studying the electrochemical behaviour of haemoglobin directly from human blood, for various scientific and clinical purposes.

  15. Direct in vivo electrochemical detection of haemoglobin in red blood cells.

    PubMed

    Toh, Rou Jun; Peng, Weng Kung; Han, Jongyoon; Pumera, Martin

    2014-08-28

    The electrochemical behavior of iron ion in haemoglobin provides insight to the chemical activity in the red blood cell which is important in the field of hematology. Herein, the detection of haemoglobin in human red blood cells on glassy carbon electrode (GC) was demonstrated. Red blood cells or raw blood cells was immobilized on a glassy carbon electrode surface with Nafion films employed to sandwich the layer of biological sample firmly on the electrode surface. Cyclic voltammetry (CV) analyses revealed a well-defined reduction peak for haemoglobin at about -0.30 V (vs. Ag/AgCl) at the red blood cell (GC-Nf-RBC-3Nf) and blood (GC-Nf-B-3Nf) film modified GCE in a pH 3.5 phosphate buffer solution. We further demonstrated that the complex biological conditions of a human red blood cell displayed no interference with the detection of haemoglobin. Such findings shall have an implication on the possibilities of studying the electrochemical behaviour of haemoglobin directly from human blood, for various scientific and clinical purposes.

  16. Direct In Vivo Electrochemical Detection of Haemoglobin in Red Blood Cells

    PubMed Central

    Toh, Rou Jun; Peng, Weng Kung; Han, Jongyoon; Pumera, Martin

    2014-01-01

    The electrochemical behavior of iron ion in haemoglobin provides insight to the chemical activity in the red blood cell which is important in the field of hematology. Herein, the detection of haemoglobin in human red blood cells on glassy carbon electrode (GC) was demonstrated. Red blood cells or raw blood cells was immobilized on a glassy carbon electrode surface with Nafion films employed to sandwich the layer of biological sample firmly on the electrode surface. Cyclic voltammetry (CV) analyses revealed a well-defined reduction peak for haemoglobin at about −0.30 V (vs. Ag/AgCl) at the red blood cell (GC-Nf-RBC-3Nf) and blood (GC-Nf-B-3Nf) film modified GCE in a pH 3.5 phosphate buffer solution. We further demonstrated that the complex biological conditions of a human red blood cell displayed no interference with the detection of haemoglobin. Such findings shall have an implication on the possibilities of studying the electrochemical behaviour of haemoglobin directly from human blood, for various scientific and clinical purposes. PMID:25163492

  17. Biology, detection, and clinical implications of circulating tumor cells

    PubMed Central

    Joosse, Simon A; Gorges, Tobias M; Pantel, Klaus

    2015-01-01

    Cancer metastasis is the main cause of cancer-related death, and dissemination of tumor cells through the blood circulation is an important intermediate step that also exemplifies the switch from localized to systemic disease. Early detection and characterization of circulating tumor cells (CTCs) is therefore important as a general strategy to monitor and prevent the development of overt metastatic disease. Furthermore, sequential analysis of CTCs can provide clinically relevant information on the effectiveness and progression of systemic therapies (e.g., chemo-, hormonal, or targeted therapies with antibodies or small inhibitors). Although many advances have been made regarding the detection and molecular characterization of CTCs, several challenges still exist that limit the current use of this important diagnostic approach. In this review, we discuss the biology of tumor cell dissemination, technical advances, as well as the challenges and potential clinical implications of CTC detection and characterization. PMID:25398926

  18. Cord blood T cells mediate enhanced antitumor effects compared with adult peripheral blood T cells.

    PubMed

    Hiwarkar, Prashant; Qasim, Waseem; Ricciardelli, Ida; Gilmour, Kimberly; Quezada, Sergio; Saudemont, Aurore; Amrolia, Persis; Veys, Paul

    2015-12-24

    Unrelated cord blood transplantation (CBT) without in vivo T-cell depletion is increasingly used to treat high-risk hematologic malignancies. Following T-replete CBT, naïve CB T cells undergo rapid peripheral expansion with memory-effector differentiation. Emerging data suggest that unrelated CBT, particularly in the context of HLA mismatch and a T-replete graft, may reduce leukemic relapse. To study the role of CB T cells in mediating graft-versus-tumor responses and dissect the underlying immune mechanisms for this, we compared the ability of HLA-mismatched CB and adult peripheral blood (PB) T cells to eliminate Epstein-Barr virus (EBV)-driven human B-cell lymphoma in a xenogeneic NOD/SCID/IL2rg(null) mouse model. CB T cells mediated enhanced tumor rejection compared with equal numbers of PB T cells, leading to improved survival in the CB group (P < .0003). Comparison of CB T cells that were autologous vs allogeneic to the lymphoma demonstrated that this antitumor effect was mediated by alloreactive rather than EBV-specific T cells. Analysis of tumor-infiltrating lymphocytes demonstrated that CB T cells mediated this enhanced antitumor effect by rapid infiltration of the tumor with CCR7(+)CD8(+) T cells and prompt induction of cytotoxic CD8(+) and CD4(+) T-helper (Th1) T cells in the tumor microenvironment. In contrast, in the PB group, this antilymphoma effect is impaired because of delayed tumoral infiltration of PB T cells and a relative bias toward suppressive Th2 and T-regulatory cells. Our data suggest that, despite being naturally programmed toward tolerance, reconstituting T cells after unrelated T-replete CBT may provide superior Tc1-Th1 antitumor effects against high-risk hematologic malignancies.

  19. Born approximation model for light scattering by red blood cells.

    PubMed

    Lim, Joonoh; Ding, Huafeng; Mir, Mustafa; Zhu, Ruoyu; Tangella, Krishnarao; Popescu, Gabriel

    2011-10-01

    The primary role of a red blood cell (RBC) is delivering oxygen throughout our body. Abnormalities of this basic function lead to anemia and are caused by numerous diseases such as malaria and sickle cell anemia. As prompt and inexpensive tests for blood screening are in demand, we have developed a faster and reliable way to measure morphological parameters associated with the structure of red blood cells and the size distribution of the cells in a whole blood smear. Modeling the RBC shape under Born approximation, we are able to determine parameters of clinical relevance, such as the diameter, thickness and dimple size. From a measured quantitative phase image of a blood smear, we can determine the average and standard deviation of the red blood cell volume simultaneously, i.e., without analyzing each cell individually. This approach may open the door for a new generation of label-free, high-throughput blood testing.

  20. Blood cell diagnostics by a chip lensless microscope

    NASA Astrophysics Data System (ADS)

    Riesenberg, R.; Kanka, M.; Mayer, G.

    2014-02-01

    We present the digital inline holographic microscopy for blood cell counting. The microscope unit contains a pinhole chip for illumination, a micro-fluidic chip, and a CMOS-chip for detection. The design is adapted and tested for blood cell diagnostics. A single hologram delivers a stack of images for all z-positions in the micro-fluidic channel and is the basic for counting of flowing cells. Images of flowing red blood cells are presented providing clinical diagnostics.

  1. Novel, high-yield red blood cell production methods from CD34-positive cells derived from human embryonic stem, yolk sac, fetal liver, cord blood, and peripheral blood.

    PubMed

    Olivier, Emmanuel; Qiu, Caihong; Bouhassira, Eric E

    2012-08-01

    The current supply of red blood cells expressing rare blood groups is not sufficient to cover all the existing transfusion needs for chronically transfused patients, such as sickle cell disease homozygous carriers, because of alloimmunization. In vitro production of cultured red blood cells is slowly emerging as a possible complement to the existing collection-based red blood cell procurement system. The yield of cultured red blood cells can theoretically be maximized by amplifying the stem, progenitor, or precursor compartment. Here, we combined methods designed to expand these three compartments to optimize the yield of cultured red blood cells and found that exposing CD34(+) cells to a short pulse of cytokines favorable for erythroid differentiation prior to stem cell expansion followed by progenitor expansion produced the highest yield of erythroid cells. This novel serum-free red blood cell production protocol was efficient on CD34(+) cells derived from human embryonic stem cells, 6-8-week yolk sacs, 16-18-week fetal livers, cord blood, and peripheral blood. The yields of cells obtained with these new protocols were larger by an order of magnitude than the yields observed previously. Globin expression analysis by high-performance liquid chromatography revealed that these expansion protocols generally yielded red blood cells that expressed a globin profile similar to that expected for the developmental age of the CD34(+) cells.

  2. Novel, High-Yield Red Blood Cell Production Methods from CD34-Positive Cells Derived from Human Embryonic Stem, Yolk Sac, Fetal Liver, Cord Blood, and Peripheral Blood

    PubMed Central

    Olivier, Emmanuel; Qiu, Caihong

    2012-01-01

    The current supply of red blood cells expressing rare blood groups is not sufficient to cover all the existing transfusion needs for chronically transfused patients, such as sickle cell disease homozygous carriers, because of alloimmunization. In vitro production of cultured red blood cells is slowly emerging as a possible complement to the existing collection-based red blood cell procurement system. The yield of cultured red blood cells can theoretically be maximized by amplifying the stem, progenitor, or precursor compartment. Here, we combined methods designed to expand these three compartments to optimize the yield of cultured red blood cells and found that exposing CD34+ cells to a short pulse of cytokines favorable for erythroid differentiation prior to stem cell expansion followed by progenitor expansion produced the highest yield of erythroid cells. This novel serum-free red blood cell production protocol was efficient on CD34+ cells derived from human embryonic stem cells, 6–8-week yolk sacs, 16–18-week fetal livers, cord blood, and peripheral blood. The yields of cells obtained with these new protocols were larger by an order of magnitude than the yields observed previously. Globin expression analysis by high-performance liquid chromatography revealed that these expansion protocols generally yielded red blood cells that expressed a globin profile similar to that expected for the developmental age of the CD34+ cells. PMID:23197866

  3. Platelet and red blood cell utilization and transfusion independence in umbilical cord blood and allogeneic peripheral blood hematopoietic cell transplants.

    PubMed

    Solh, Melhem; Brunstein, Claudio; Morgan, Shanna; Weisdorf, Daniel

    2011-05-01

    Allogeneic hematopoietic cell transplantation (HCT) recipients have substantial transfusion requirements. Factors associated with increased transfusions and the extent of blood product use in umbilical cord blood (UCB) recipients are uncertain. We reviewed blood product use in 229 consecutive adult recipients of allogeneic HCT at the University of Minnesota: 147 with leukemia, 82 lymphoma or myeloma; 58% received unrelated UCB and 43% sibling donor peripheral blood stem cell (PBSC) grafts. Although neutrophil recovery was prompt (UCB median 17, range: 2-45 days, and PBSC 14, range: 3-34 days), only 135 of 229 (59% cumulative incidence) achieved red blood cell (RBC) independence and 157 (69%) achieved platelet independence by 6 months. Time to platelet independence was prolonged in UCB recipients (median UCB 41 versus PBSC 14 days) and in patients who had received a prior transplant (median 48 versus 32 days). Patients who received UCB grafts required more RBC through day 60 post-HCT (mean UCB 7.8 (95% confidence interval [CI] 6.7-8.9) versus PBSC 5.2 (3.7-6.7) transfusions, P = .04), and more platelet transfusions (mean 25.2 (95% CI 22.1-28.2) versus 12.9 (9.4-16.4), P < .01) compared to PBSC recipients. Patients receiving myeloablative (MA) conditioning required more RBC and platelet transfusions during the first 2 months post-HCT compared to reduced-intensity conditioning (RIC) (7.4 versus 6.2, P = .30 for RBC; 23.2 versus 17.5, P = .07 for platelets). Despite prompt neutrophil engraftment, UCB recipients had delayed platelet recovery as well as more prolonged and costly blood product requirements. Enhanced approaches to accelerate multilineage engraftment could limit the transfusion-associated morbidity and costs accompanying UCB allotransplantation.

  4. Immunoglobulin G-mediated regulation of the murine immune response to transfused red blood cells occurs in the absence of active immune suppression: implications for the mechanism of action of anti-D in the prevention of haemolytic disease of the fetus and newborn?

    PubMed Central

    Brinc, Davor; Le-Tien, Hoang; Crow, Andrew R; Siragam, Vinayakumar; Freedman, John; Lazarus, Alan H

    2008-01-01

    Anti-D has been widely and effectively used in Rhesus blood group D negative mothers for the prevention of haemolytic disease of the fetus and newborn; its mechanism of action however, often referred to as antibody-mediated immune suppression (AMIS), remains largely unresolved. We investigated, in a murine model, whether active immune suppression or clonal deletion mediated by anti-red blood cell (RBC) immunoglobulin G (IgG) could explain the phenomenon of AMIS. Transfusion of IgG-opsonized foreign RBCs (i.e. AMIS) strongly attenuated antibody responses compared to transfusion of untreated foreign RBCs. When the AMIS-mice were subsequently transfused with untreated RBCs, no immune suppression was observed at 5 and 35 days after AMIS induction; in fact, the mice responded to retransfusion with untreated RBCs in a manner that was characteristic of a secondary immune response. When IgG-opsonized RBCs were transfused concurrently with untreated RBCs, a dose-dependent reduction of the antibody response was observed. This work suggests that the attenuation of the antibody responsiveness by anti-RBC IgG is not associated with active immune suppression or clonal deletion at either the T-cell or B-cell level; rather, the effect appears more characteristic of B-cell unresponsiveness to IgG-opsonized RBCs. These results may have implications for the understanding of the mechanism of action of anti-D in haemolytic disease of the fetus and newborn. PMID:18266717

  5. Activation of Na+/H+ and K+/H+ exchange by calyculin A in Amphiuma tridactylum red blood cells: implications for the control of volume-induced ion flux activity

    PubMed Central

    Ortiz-Acevedo, Alejandro; Rigor, Robert R.; Maldonado, Hector M.; Cala, Peter M.

    2008-01-01

    Alteration in cell volume of vertebrates results in activation of volume-sensitive ion flux pathways. Fine control of the activity of these pathways enables cells to regulate volume following osmotic perturbation. Protein phosphorylation and dephosphorylation have been reported to play a crucial role in the control of volume-sensitive ion flux pathways. Exposing Amphiuma tridactylu red blood cells (RBCs) to phorbol esters in isotonic medium results in a simultaneous, dose-dependent activation of both Na+/H+ and K+/H+ exchangers. We tested the hypothesis that in Amphiuma RBCs, both shrinkage-induced Na+/H+ exchange and swelling-induced K+/H+ exchange are activated by phosphorylation-dependent reactions. To this end, we assessed the effect of calyculin A, a phosphatase inhibitor, on the activity of the aforementioned exchangers. We found that exposure of Amphiuma RBCs to calyculin-A in isotonic media results in simultaneous, 1–2 orders of magnitude increase in the activity of both K+/H+ and Na+/H+ exchangers. We also demonstrate that, in isotonic media, calyculin A-dependent increases in net Na+ uptake and K+ loss are a direct result of phosphatase inhibition and are not dependent on changes in cell volume. Whereas calyculin A exposure in the absence of volume changes results in stimulation of both the Na+/H+ and K+/H+ exchangers, superimposing cell swelling or shrinkage and calyculin A treatment results in selective activation of K+/H+ or Na+/H+ exchange, respectively. We conclude that kinase-dependent reactions are responsible for Na+/H+ and K+/H+ exchange activity, whereas undefined volume-dependent reactions confer specificity and coordinated control. PMID:18799654

  6. Separation of White Blood Cells from Red Blood Cells in a Microfabricated Lattice

    NASA Astrophysics Data System (ADS)

    Austin, Robert H.; Chan, Shirley S.

    1996-03-01

    Leukocytes (WBCs) are relatively rare in a healthy person: approximately 1 out of every thousand cells in the blood are WBCs, the rest are predominantly the un-nucleated erythrocytes (RBCs). Chemotactic control of WBC invasion of small openings (one micron or less) is a critical element in understanding, and perhaps someday controlling, the invasive and lethal transformation of WBCs in leukemia. Quantitative study and understanding of the physical phenomena involved in chemotaxis requires the ability to both capture from blood the relatively rare WBCs and then to challenge them with a precise array of variable sized openings in the presence of a known chemical gradient. We have recently been able to show that a suitably chosen opening in microlithographically constructed array structures can with 100% efficiency sort rare white blood cells from red blood cells and hold them for optical observation under a transparent glass lid. We have developed sensitive fluorescence and dark-field techniques to observe the signal transduction and motile response to both hydrodynamic shear fields and chemotactic patterns. Videos of this work will be shown.

  7. Effects of red blood cells on hemostasis.

    PubMed

    Roeloffzen, Wilfried W H; Kluin-Nelemans, Hanneke C; Bosman, Lotte; de Wolf, Joost Th M

    2010-07-01

    Currently there is no sensitive laboratory test to establish the influence of red blood cells (RBCs) on hemostasis. As thromboelastography (TEG) measures hemostasis in whole blood, taking into account the interactions of all cellular elements, we used this instrument to investigate the role that RBCs play in hemostasis. In 29 patients with chemotherapy-induced anemia we studied the effect of progressive anemia on the coagulation profile. In 24 patients with chronic anemia we studied the effect of transfusion of RBCs on coagulation. Finally, in 18 patients we evaluated whether storage time of RBCs has additional effects on hemostasis. We observed a significant negative correlation between hemoglobin and TEG variables related to both clot strength and elasticity (p < 0.05). Moreover, anemia was associated with a delay in the initiation of the coagulation cascade. Correction of anemia by RBC transfusion resulted in significant shortening of this initiation phase with now the opposite effect on clot strength and elasticity. The negative effects on clot quality were significantly worse when fresh RBCs were transfused compared to longer-stored RBCs. Furthermore, in contrast to the longer-stored RBCs, fresh RBCs did not enhance initial fibrin formation. In this study we found that anemia was associated with a delay in the initiation of the coagulation cascade with a finally formed clot with superior strength and viscoelastic properties. Transfusion of RBCs was associated with impaired clot quality, with even worse effects on the initial fibrin build-up and clot quality by fresh RBCs.

  8. Counting white blood cells using morphological granulometries

    NASA Astrophysics Data System (ADS)

    Theera-Umpon, Nipon; Gader, Paul D.

    2000-04-01

    We describe a modification of the mixture proportion estimation algorithm based on the granulometric mixing theorem. The modified algorithm is applied to the problem of counting different types of white blood cells in bone marrow images. In principle, the algorithm can be used to count the proportion of cells in each class without explicitly segmenting and classifying them. The direct application of the original algorithm does not converge well for more than two classes. The modified algorithm uses prior statistics to initially segment the mixed pattern spectrum and then applies the one-primitive estimation algorithm to each initial component. Applying the algorithm to one class at a time results in better convergence. The counts produced by the modified algorithm on six classes of cells--myeloblast, promyelocyte, myelocyte, metamyelocyte, band, and PolyMorphoNuclear--are very close to the human expert's numbers; the deviation of the algorithm counts is similar to the deviation of counts produced by human experts. The important technical contributions are that the modified algorithm uses prior statistics for each shape class in place or prior knowledge of the total number of objects in an image, and it allows for more than one primitive from each class.

  9. Fluorometric assay for red blood cell antibodies

    SciTech Connect

    Schreiber, A.B.; Lambermont, M.; Strosberg, A.D.; Wybran, J.

    1981-03-01

    A fluorometric assay is described for the detection of red blood cell antibodies. The assay reveals as little as 600 molecules of bound, fluoroesceinated rabbit anti-human IgG antibodies per erythrocyte. Eleven patients with possible autoimmune erythrocyte disorder and negative direct antiglobulin test were studied by the fluorometric assay. The outcome of the fluorometric assay was compared with that of the human allogeneic rosette test. Results obtained by the two methods were in complete agreement. Five of the patients were shown to possess unexpectedly high levels of erythrocyte-bound IgG in spite of a negative, direct antiglobulin test. These findings and the validity of the fluorometric assay are discussed.

  10. Inflammatory Cytokines and White Blood Cell Counts ...

    EPA Pesticide Factsheets

    Epidemiological observations of urban inhalation exposures to diesel exhaust (DE) and ozone (O3) have shown pre-clinical cardiopulmonary responses in humans. Identifying the key biological mechanisms that initiate these health bioindicators is difficult due to variability in environmental exposure in time and from person to person. Previously, environmentally controlled human exposure chambers have been used to study DE and O3 dose-response patterns separately, but investigation of co-exposures has not been performed under controlled conditions. Because a mixture is a more realistic exposure scenario for the general public, in this study we investigate the relationships of urban levels of urban-level DE exposure (300 μg/m3), O3 (0.3 ppm), DE + O3 co-exposure, and innate immune system responses. Fifteen healthy human volunteers were studied for changes in ten inflammatory cytokines (interleukins 1β, 2, 4, 5, 8, 10, 12p70 and 13, IFN-γ, and TNF-α) and counts of three white blood cell types (lymphocytes, monocytes, and neutrophils) following controlled exposures to DE, O3, and DE+O3. The results show subtle cytokines responses to the diesel-only and ozone-only exposures, and that a more complex (possibly synergistic) relationship exists in the combination of these two exposures with suppression of IL-5, IL-12p70, IFN-γ, and TNF-α that persists up to 22-hours for IFN-γ and TNF-α. The white blood cell differential counts showed significant monocyte and lympho

  11. Portable microfluidic cytometer for whole blood cell analysis

    NASA Astrophysics Data System (ADS)

    Grafton, Meggie M.; Zordan, Michael D.; Chuang, Han-Sheng; Rajdev, Pooja; Reece, Lisa M.; Irazoqui, Pedro P.; Wereley, Steven T.; Byrnes, Ron; Todd, Paul; Leary, James F.

    2010-02-01

    Lab-on-a-chip (LOC) systems allow complex laboratory assays to be carried out on a single chip using less time, reagents, and manpower than traditional methods. There are many chips addressing PCR and other DNA assays, but few that address blood cell analysis. Blood analysis, particularly of the cellular component, is highly important in both medical and scientific fields. Traditionally blood samples require a vial of blood, then several processing steps to separate and stain the various components, followed by the preparations for each specific assay to be performed. A LOC system for blood cell analysis and sorting would be ideal. The microfluidic-based system we have developed requires a mere drop of blood to be introduced onto the chip. Once on chip, the blood is mixed with both fluorescent and magnetic labels. The lab-on-a-chip device then uses a syringe drive to push the cells through the chip, while a permanent magnet is positioned to pull the magnetically labeled white blood cells to a separate channel. The white blood cells, labeled with different color fluorescent quantum dots (Qdots) conjugated to antibodies against WBC subpopulations, are analyzed and counted, while a sampling of red blood cells is also counted in a separate channel. This device will be capable of processing whole blood samples on location in a matter of minutes and displaying the cell count and should eventually find use in neonatology, AIDS and remote site applications.

  12. SBR-Blood: systems biology repository for hematopoietic cells.

    PubMed

    Lichtenberg, Jens; Heuston, Elisabeth F; Mishra, Tejaswini; Keller, Cheryl A; Hardison, Ross C; Bodine, David M

    2016-01-04

    Extensive research into hematopoiesis (the development of blood cells) over several decades has generated large sets of expression and epigenetic profiles in multiple human and mouse blood cell types. However, there is no single location to analyze how gene regulatory processes lead to different mature blood cells. We have developed a new database framework called hematopoietic Systems Biology Repository (SBR-Blood), available online at http://sbrblood.nhgri.nih.gov, which allows user-initiated analyses for cell type correlations or gene-specific behavior during differentiation using publicly available datasets for array- and sequencing-based platforms from mouse hematopoietic cells. SBR-Blood organizes information by both cell identity and by hematopoietic lineage. The validity and usability of SBR-Blood has been established through the reproduction of workflows relevant to expression data, DNA methylation, histone modifications and transcription factor occupancy profiles.

  13. Nanoparticles isolated from blood: a reflection of vesiculability of blood cells during the isolation process

    PubMed Central

    Šuštar, Vid; Bedina-Zavec, Apolonija; Štukelj, Roman; Frank, Mojca; Bobojević, Goran; Janša, Rado; Ogorevc, Eva; Kruljc, Peter; Mam, Keriya; Šimunič, Boštjan; Manček-Keber, Mateja; Jerala, Roman; Rozman, Blaž; Veranič, Peter; Hägerstrand, Henry; Kralj-Iglič, Veronika

    2011-01-01

    Background Shedding of nanoparticles from the cell membrane is a common process in all cells. These nanoparticles are present in body fluids and can be harvested by isolation. To collect circulating nanoparticles from blood, a standard procedure consisting of repeated centrifugation and washing is applied to the blood samples. Nanoparticles can also be shed from blood cells during the isolation process, so it is unclear whether nanoparticles found in the isolated material are present in blood at sampling or if are they created from the blood cells during the isolation process. We addressed this question by determination of the morphology and identity of nanoparticles harvested from blood. Methods The isolates were visualized by scanning electron microscopy, analyzed by flow cytometry, and nanoparticle shapes were determined theoretically. Results The average size of nanoparticles was about 300 nm, and numerous residual blood cells were found in the isolates. The shapes of nanoparticles corresponded to the theoretical shapes obtained by minimization of the membrane free energy, indicating that these nanoparticles can be identified as vesicles. The concentration and size of nanoparticles in blood isolates was sensitive to the temperature during isolation. We demonstrated that at lower temperatures, the nanoparticle concentration was higher, while the nanoparticles were on average smaller. Conclusion These results indicate that a large pool of nanoparticles is produced after blood sampling. The shapes of deformed blood cells found in the isolates indicate how fragmentation of blood cells may take place. The results show that the contents of isolates reflect the properties of blood cells and their interaction with the surrounding solution (rather than representing only nanoparticles present in blood at sampling) which differ in different diseases and may therefore present a relevant clinical parameter. PMID:22128248

  14. Preoperative blood transfusions for sickle cell disease

    PubMed Central

    Estcourt, Lise J; Fortin, Patricia M; Trivella, Marialena; Hopewell, Sally

    2016-01-01

    Background Sickle cell disease is one of the commonest severe monogenic disorders in the world, due to the inheritance of two abnormal haemoglobin (beta globin) genes. Sickle cell disease can cause severe pain, significant end-organ damage, pulmonary complications, and premature death. Surgical interventions are more common in people with sickle cell disease, and occur at much younger ages than in the general population. Blood transfusions are frequently used prior to surgery and several regimens are used but there is no consensus over the best method or the necessity of transfusion in specific surgical cases. This is an update of a Cochrane review first published in 2001. Objectives To determine whether there is evidence that preoperative blood transfusion in people with sickle cell disease undergoing elective or emergency surgery reduces mortality and perioperative or sickle cell-related serious adverse events. To compare the effectiveness of different transfusion regimens (aggressive or conservative) if preoperative transfusions are indicated in people with sickle cell disease. Search methods We searched for relevant trials in The Cochrane Library, MEDLINE (from 1946), Embase (from 1974), the Transfusion Evidence Library (from 1980), and ongoing trial databases; all searches current to 23 March 2016. We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register: 18 January 2016. Selection criteria All randomised controlled trials and quasi-randomised controlled trials comparing preoperative blood transfusion regimens to different regimens or no transfusion in people with sickle cell disease undergoing elective or emergency surgery. There was no restriction by outcomes examined, language or publication status. Data collection and analysis Two authors independently assessed trial eligibility and the risk of bias and extracted data. Main results Three trials with 990 participants were eligible for inclusion in the review. There were no

  15. Antigen negative red blood cell inventory of Indian blood donors.

    PubMed

    Kulkarni, Swati; Vasantha, K; Ghosh, Kanjaksha

    2016-08-01

    Screening the donor population for clinically important antigens and creating a database of phenotyped donors will eliminate the tedious task of large scale screening for antigen negative units. The aim of the present study is to identify donors lacking common antigens and a combination of common antigens to establish an antigen negative inventory. Blood samples of 1221 regular blood donors were phenotyped for the clinically important common antigens of the Rh, Duffy, Kell, Kidd and MNS blood group systems using standard tube technique. Out of 1221 total donors tested, we observed that 261 donors lacked a combination of clinically important common antigens (C, D, e, Fya, Jka, s). After excluding the RhD negative donors in this study 15.56% lacked a combination of two or three common antigens. Of all donors, 3.2% lacked Fya and Jka antigens, 1.96% Fya and s, 1.88% Jka and s antigens and 0.57% lacked three common antigens. An antigen negative inventory of donors who lack a single common antigen or a combination of common antigens was prepared from regular donors which will prove useful for efficient management of transfusion therapy in patients with multiple antibodies against common antigens. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Meanings of blood, bleeding and blood donations in Pakistan: implications for national vs global safe blood supply policies

    PubMed Central

    Mumtaz, Zubia; Bowen, Sarah; Mumtaz, Rubina

    2012-01-01

    Contemporary public policy, supported by international arbitrators of blood policy such as the World Health Organization and the International Federation of the Red Cross, asserts that the safest blood is that donated by voluntary, non-remunerated donors from low-risk groups of the population. These policies promote anonymous donation and discourage kin-based or replacement donation. However, there is reason to question whether these policies, based largely on Western research and beliefs, are the most appropriate for ensuring an adequate safe blood supply in many other parts of the world. This research explored the various and complex meanings embedded in blood using empirical ethnographic data from Pakistan, with the intent of informing development of a national blood policy in that country. Using a focused ethnographic approach, data were collected in 26 in-depth interviews, 6 focus group discussions, 12 key informant interviews and 25 hours of observations in blood banks and maternity and surgical wards. The key finding was that notions of caste-based purity of blood, together with the belief that donors and recipients are symbolically knitted in a kin relationship, place a preference on kin-blood. The anonymity inherent in current systems of blood extraction, storage and use as embedded in contemporary policy discourse and practice was problematic as it blurred distinctions that were important within this society. The article highlights the importance—to ensuring a safe blood supply—of basing blood procurement policies on local, context-specific belief systems rather than relying on uniform, one-size-fits-all global policies. Drawing on our empirical findings and the literature, it is argued that the practice of kin-donated blood remains a feasible alternative to the global ideal of voluntary, anonymous donations. There is a need to focus on developing context-sensitive strategies for promoting blood safety, and critically revisit the assumptions

  17. Meanings of blood, bleeding and blood donations in Pakistan: implications for national vs global safe blood supply policies.

    PubMed

    Mumtaz, Zubia; Bowen, Sarah; Mumtaz, Rubina

    2012-03-01

    Contemporary public policy, supported by international arbitrators of blood policy such as the World Health Organization and the International Federation of the Red Cross, asserts that the safest blood is that donated by voluntary, non-remunerated donors from low-risk groups of the population. These policies promote anonymous donation and discourage kin-based or replacement donation. However, there is reason to question whether these policies, based largely on Western research and beliefs, are the most appropriate for ensuring an adequate safe blood supply in many other parts of the world. This research explored the various and complex meanings embedded in blood using empirical ethnographic data from Pakistan, with the intent of informing development of a national blood policy in that country. Using a focused ethnographic approach, data were collected in 26 in-depth interviews, 6 focus group discussions, 12 key informant interviews and 25 hours of observations in blood banks and maternity and surgical wards. The key finding was that notions of caste-based purity of blood, together with the belief that donors and recipients are symbolically knitted in a kin relationship, place a preference on kin-blood. The anonymity inherent in current systems of blood extraction, storage and use as embedded in contemporary policy discourse and practice was problematic as it blurred distinctions that were important within this society. The article highlights the importance-to ensuring a safe blood supply-of basing blood procurement policies on local, context-specific belief systems rather than relying on uniform, one-size-fits-all global policies. Drawing on our empirical findings and the literature, it is argued that the practice of kin-donated blood remains a feasible alternative to the global ideal of voluntary, anonymous donations. There is a need to focus on developing context-sensitive strategies for promoting blood safety, and critically revisit the assumptions underlying

  18. Relationship between blood lead levels and blood pressure and its cardiovascular risk implications

    SciTech Connect

    Pirkle, J.L.; Schwartz, J.; Landis, J.R.; Harlan, W.R.

    1985-02-01

    The relationship between blood pressure and blood lead levels in the second National Health and Nutrition Examination Survey (1976-1980) has been examined for white males aged 40-59 years. After adjustment for age, body mass index, nutritional factors, and blood biochemistries in a multiple linear regression model, the relationship of systolic and diastolic blood pressures to blood lead levels was statistically significant (p < 0.01). There was no evidence of a threshold blood lead level for this relationship. Although these data alone do not prove a causal relationship between low blood lead levels and blood pressure, the findings are consistent with current epidemiologic and animal studies, indicating that a causal reationship is probable. To examine the potential health risks, the multiple logistic risk factor coefficients from the Pooling Project and Framingham studies were used to predict the impact of the 37% decrease in mean blood lead levels which occurred in adult white males from 1976 to 1980. As a result of this blood lead decrease, the calculations predicted a 4.7% decrease in the incidence of fatal and nonfatal myocardial infarction over 10 years, a 6.7% decrease in the incidence of fatal and nonfatal strokes over 10 years, and a 5.5% decrease in the incidence of death from all causes over 11.5 years. In addition, as a result of this blood lead decrease, the predicted number of white males in this age group with hypertension (diastolic blood pressure greater than or equal to 90 mmHg) decreased by 17.5%.

  19. [Changes in blood pressure during static work. Practical implication].

    PubMed

    Kahn, J F; Monod, H

    1989-08-01

    while the cardiocirculatory response to dynamic exercises (e.g. running, cycling, swimming) is the object of the physician's full attention, the cardiovascular repercussions of static exercises, such as weight-lifting, sustained postures in gymnastics or immobilization in judo, are often ignored. Yet any sustained isometric contraction is associated from the art with an increase in blood pressure which may be major and involves about equally the systolic and diastolic pressures. As soon as the strength developed by the muscle exceeds 20 p. 100 of its maximum voluntary strength (MVS) the increase of blood pressure continues until the contraction comes to an end. Whatever the muscle used, the intensity of a cardiovascular response is independent of the muscular mass in action, but it mostly depends on the MVS percentage This rise in blood pressure is mainly due to an increase in heart and cardiac output. The reactions are such that relatively moderate and localized static effort may result in a rapid and important increase in myocardial work, and this may cause serious accidents in subject with a cardiovascular weakness, either isolated or associated with such risk factors as age or arterial hypertension. In consequence, adults who are insufficiently trained and present with one or several risk factors should avoid sports which required frequent respiratory arrests and/or sustained postures. If such sports are nevertheless chosen, it would seem that practising also a dynamic sport relying on aerobic metabolism might lin , at least in part, the effects of increased blood pressure due to static activities.

  20. Destruction of newly released red blood cells in space flight

    NASA Technical Reports Server (NTRS)

    Alfrey, C. P.; Udden, M. M.; Huntoon, C. L.; Driscoll, T.

    1996-01-01

    Space flight results in a rapid change in total blood volume, plasma volume, and red blood cell mass because the space to contain blood is decreased. The plasma volume and total blood volume decreases during the first hours in space and remain at a decreased level for the remainder of the flight. During the first several hours following return to earth, plasma volume and total blood volume increase to preflight levels. During the first few days in space recently produced red blood cells disappear from the blood resulting in a decrease in red blood cell mass of 10-15%. Red cells 12 d old or older survive normally and production of new cells continues at near preflight levels. After the first few days in space, the red cell mass is stable at the decreased level. Following return to earth the hemoglobin and red blood cell mass concentrations decrease reflecting the increase in plasma volume. The erythropoietin levels increase responding to "postflight anemia"; red cell production increases, and the red cell mass is restored to preflight levels after several weeks.

  1. Destruction of newly released red blood cells in space flight

    NASA Technical Reports Server (NTRS)

    Alfrey, C. P.; Udden, M. M.; Huntoon, C. L.; Driscoll, T.

    1996-01-01

    Space flight results in a rapid change in total blood volume, plasma volume, and red blood cell mass because the space to contain blood is decreased. The plasma volume and total blood volume decreases during the first hours in space and remain at a decreased level for the remainder of the flight. During the first several hours following return to earth, plasma volume and total blood volume increase to preflight levels. During the first few days in space recently produced red blood cells disappear from the blood resulting in a decrease in red blood cell mass of 10-15%. Red cells 12 d old or older survive normally and production of new cells continues at near preflight levels. After the first few days in space, the red cell mass is stable at the decreased level. Following return to earth the hemoglobin and red blood cell mass concentrations decrease reflecting the increase in plasma volume. The erythropoietin levels increase responding to "postflight anemia"; red cell production increases, and the red cell mass is restored to preflight levels after several weeks.

  2. Backward elastic light scattering of malaria infected red blood cells

    NASA Astrophysics Data System (ADS)

    Lee, Seungjun; Lu, Wei

    2011-08-01

    We investigated the backward light scattering pattern of healthy and malaria (Plasmodium falciparum) parasitized red blood cells. The spectrum could clearly distinguish between predominant ring stage infected blood cells and healthy blood cells. Further, we found that infected samples mixed with different stages of P. falciparum showed different signals, suggesting that even variance in parasite stages could also be detected by the spectrum. These results together with the backward scattering technique suggest the potential of non-invasive diagnosis of malaria through light scattering of blood cells near the surface of human body, such as using eyes or skin surface.

  3. Infusion of hemolyzed red blood cells within peripheral blood stem cell grafts in patients with and without sickle cell disease.

    PubMed

    Fitzhugh, Courtney D; Unno, Hayato; Hathaway, Vincent; Coles, Wynona A; Link, Mary E; Weitzel, R Patrick; Zhao, Xiongce; Wright, Elizabeth C; Stroncek, David F; Kato, Gregory J; Hsieh, Matthew M; Tisdale, John F

    2012-06-14

    Peripheral blood stem cell (PBSC) infusions are associated with complications such as elevated blood pressure and decreased creatinine clearance. Patients with sickle cell disease experience similar manifestations, and some have postulated release of plasma-free hemoglobin with subsequent nitric oxide consumption as causative. We sought to evaluate whether the infusion of PBSC grafts containing lysed red blood cells (RBCs) leads to the toxicity observed in transplant subjects. We report a prospective cohort study of 60 subjects divided into 4 groups based on whether their infusions contained dimethyl sulfoxide (DMSO) and lysed RBCs, no DMSO and fresh RBCs, DMSO and no RBCs, or saline. Our primary end point, change in maximum blood pressure compared with baseline, was not significantly different among groups. Tricuspid regurgitant velocity and creatinine levels also did not differ significantly among groups. Our data do not support free hemoglobin as a significant contributor to toxicity associated with PBSC infusions. This study was registered at clinicaltrials.gov (NCT00631787).

  4. Developmental Plasticity of Red Blood Cell Homeostasis

    PubMed Central

    Golub, Mari S.; Hogrefe, Casey E.; Malka, Roy; Higgins, John M.

    2014-01-01

    Most human physiologic set points like body temperature are tightly regulated and show little variation between healthy individuals. Red blood cell (RBC) characteristics such as hematocrit (HCT) and mean cell volume (MCV) are stable within individuals but can vary by 20% from one healthy person to the next. The mechanisms for the majority of this inter-individual variation are unknown and do not appear to involve common genetic variation. Here we show that environmental conditions present during development, namely in utero iron availability, can exert long-term influence on a set point related to the RBC life cycle. In a controlled study of rhesus monkeys and a retrospective study of humans, we use a mathematical model of in vivo RBC population dynamics to show that in utero iron deficiency is associated with a lowered threshold for RBC clearance and turnover. This in utero effect is plastic, persisting at least two years after birth and after the cessation of iron deficiency. Our study reports a rare instance of developmental plasticity in the human hematologic systems and also shows how mathematical modeling can be used to identify cellular mechanisms involved in the adaptive control of homeostatic set points. PMID:24415575

  5. Polypeptide multilayer nanofilm artificial red blood cells.

    PubMed

    Palath, Naveen; Bhad, Sujaykumar; Montazeri, Reza; Guidry, Christopher A; Haynie, Donald T

    2007-04-01

    Reliable encapsulation of hemoglobin (Hb) within polypeptide multilayer nanofilms has been achieved by a template-based approach, and protein functionality has been demonstrated postencapsulation. The method is general in scope and could be useful for many other encapsulants. Met-Hb was adsorbed onto 5 microm-diameter CaCO3 microparticles, and the Hb-coated particles were encapsulated within a multilayer nanofilm of poly(L-glutamic acid) (PLGA) and poly(L-lysine) (PLL) by layer-by-layer assembly. The CaCO3 templates were then dissolved within the PLGA/PLL nanofilms by addition of ethylenediaminetetraacetic acid. Encapsulation of Hb was proved by fluorescence microscopy, the pH-dependence of retention of Hb was determined by visible wavelength absorbance, and conversion of the encapsulated met-Hb to deoxy-Hb and oxy-Hb was demonstrated by spectroscopic analysis of the Soret absorption peak under various conditions. It thus has been shown that control of Hb oxygenation within polypeptide multilayer nanofilm artificial cells is possible, and that Hb thus encapsulated can bind, release, and subsequently rebind molecular oxygen. This work therefore represents an advance in the development of polypeptide multilayer film artificial red blood cells. (c) 2006 Wiley Periodicals, Inc.

  6. Red blood cell volume in preterm neonates

    SciTech Connect

    Quaife, M.A.; Dirksen, J.W.; Paxson, C.L. Jr.; McIntire, R.H. Jr.

    1981-10-01

    In the high-risk neonate, the direct determination of the red cell volume by radionuclide dilution technique appears to be the singularly definitive method of defining treatment efficacy, and is thus a useful evaluation and management tool for the pediatrician. For effective patient management, the red blood cell(RBC) volume of 69 preterm and term neonates was determined. The method utilized, Tc-99m-labeled RBCs, provided a fast and accurate answer with a large reduction in the absorbed radiation dose. In the population studied within a high-risk newborn ICU, the mean RBC volumes between the preterm and term neonates were without significant difference. Grouping and analysis of the RBC volume data with respect to birth weight, gestational ages, and 1- and 5-minute Apgar scores revealed on statistical difference. The mean value found in our population, 32.2 +/- 9.2 ml/kg, however, does differ from those previously reported in which the determinations were made using an indirect estimation from the plasma compartment.

  7. Changes in CD34+ cell count in peripheral blood after whole blood donation.

    PubMed

    Pala, Cigdem; Mumcuoglu, Haluk; Kurnaz, Fatih; Sivgin, Serdar; Kaynar, Leylagul; Keklik, Muzaffer; Akyol, Gulsah; Koker, Yavuz; Eser, Bulent

    2013-10-01

    We aimed to investigate the change in the number of stem cells and white cells in the early period following blood donation. 22 male (71%) and 9 female (29%), 31 volunteers in total were included in the study. 450 ml of whole blood were collected from each of the volunteers for the donation. Complete blood counts were performed on the volunteers before and at 6 and 24h after the donation and CD34+ cell counts per ml of peripheral blood were measured by flow cytometry technique. There was a statistically significant increase in the number of CD34+ cells in the peripheral blood at 6h following blood donation (p<0.001). At 24h, however, there was a statistically significant decrease in the number of CD34+ cells, compared to 6h (p<0.001). There was a statistically significant increase in the number of leukocytes in the peripheral blood at 6h following blood donation (p<0.001). At 24h, there was a decrease in the number of leukocytes, which was statistically significant compared to 6h (p<0.001). When the difference in CD34+ cell and leukocytes counts before blood donation and at 24h after blood donation were compared, the results were not statistically significant. As the result of this study, a transient increase in the number of CD34+ cells in the peripheral blood after blood donation was demonstrated, with a decline in CD34+ cell counts back to levels prior to donation at 24h. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Numerical analysis on cell-cell interaction of red blood cells during sedimentation

    NASA Astrophysics Data System (ADS)

    Shi, Xing

    2017-07-01

    The long-range hydrodynamic interaction among red blood cells plays an important role on the macroscopic behaviors, however, the molecular interaction at such scale is much weaker. In this paper, the sedimentations under external body force of two red blood cells are numerical simulated to investigate the hydrodynamic interaction between cells. The flow is solved by lattice Boltzmann method and the membrane of red blood cell is model by the spring model where the fluid-membrane interaction is coupled by fictitious domain method. It is found that the cells have the tendency to aggregate and may be aligned in a line along the sediment direction. Compared to the properties of a single cell under the same conditions, the sediment velocity of red blood cell group is larger; the leading cell deforms less and the following cell endures larger deformation.

  9. Phenotype and functions of memory Tfh cells in human blood.

    PubMed

    Schmitt, Nathalie; Bentebibel, Salah-Eddine; Ueno, Hideki

    2014-09-01

    Our understanding of the origin and functions of human blood CXCR5(+) CD4(+) T cells found in human blood has changed dramatically in the past years. These cells are currently considered to represent a circulating memory compartment of T follicular helper (Tfh) lineage cells. Recent studies have shown that blood memory Tfh cells are composed of phenotypically and functionally distinct subsets. Here, we review the current understanding of human blood memory Tfh cells and the subsets within this compartment. We present a strategy to define these subsets based on cell surface profiles. Finally, we discuss how increased understanding of the biology of blood memory Tfh cells may contribute insight into the pathogenesis of autoimmune diseases and the mode of action of vaccines.

  10. WBC (White Blood Cell) Differential Count

    MedlinePlus

    ... Blood Smear , Bone Marrow Aspiration and Biopsy , Immunophenotyping , Chromosome Analysis All content on Lab Tests Online has ... such as a blood smear , bone marrow biopsy , chromosome analysis , or immunophenotyping (e.g., flow cytometry). These ...

  11. Numerical Simulation of Sickle Cell Blood Flow in the Microcirculation

    NASA Astrophysics Data System (ADS)

    Berger, Stanley A.; Carlson, Brian E.

    2001-11-01

    A numerical simulation of normal and sickle cell blood flow through the transverse arteriole-capillary microcirculation is carried out to model the dominant mechanisms involved in the onset of vascular stasis in sickle cell disease. The transverse arteriole-capillary network is described by Strahler's network branching method, and the oxygen and blood transport in the capillaries is modeled by a Krogh cylinder analysis utilizing Lighthill's lubrication theory, as developed by Berger and King. Poiseuille's law is used to represent blood flow in the arterioles. Applying this flow and transport model and utilizing volumetric flow continuity at each network bifurcation, a nonlinear system of equations is obtained, which is solved iteratively using a steepest descent algorithm coupled with a Newton solver. Ten different networks are generated and flow results are calculated for normal blood and sickle cell blood without and with precapillary oxygen loss. We find that total volumetric blood flow through the network is greater in the two sickle cell blood simulations than for normal blood owing to the anemia associated with sickle cell disease. The percentage of capillary blockage in the network increases dramatically with decreasing pressure drop across the network in the sickle cell cases while there is no blockage when normal blood flows through simulated networks. It is concluded that, in sickle cell disease, without any vasomotor dilation response to decreasing oxygen concentrations in the blood, capillary blockage will occur in the microvasculature even at average pressure drops across the transverse arteriole-capillary networks.

  12. Identification and red blood cell automated counting from blood smear images using computer-aided system.

    PubMed

    Acharya, Vasundhara; Kumar, Preetham

    2017-08-17

    Red blood cell count plays a vital role in identifying the overall health of the patient. Hospitals use the hemocytometer to count the blood cells. Conventional method of placing the smear under microscope and counting the cells manually lead to erroneous results, and medical laboratory technicians are put under stress. A computer-aided system will help to attain precise results in less amount of time. This research work proposes an image-processing technique for counting the number of red blood cells. It aims to examine and process the blood smear image, in order to support the counting of red blood cells and identify the number of normal and abnormal cells in the image automatically. K-medoids algorithm which is robust to external noise is used to extract the WBCs from the image. Granulometric analysis is used to separate the red blood cells from the white blood cells. The red blood cells obtained are counted using the labeling algorithm and circular Hough transform. The radius range for the circle-drawing algorithm is estimated by computing the distance of the pixels from the boundary which automates the entire algorithm. A comparison is done between the counts obtained using the labeling algorithm and circular Hough transform. Results of the work showed that circular Hough transform was more accurate in counting the red blood cells than the labeling algorithm as it was successful in identifying even the overlapping cells. The work also intends to compare the results of cell count done using the proposed methodology and manual approach. The work is designed to address all the drawbacks of the previous research work. The research work can be extended to extract various texture and shape features of abnormal cells identified so that diseases like anemia of inflammation and chronic disease can be detected at the earliest.

  13. Adequacy and pattern of blood donations in north-eastern Nigeria: the implications for blood safety.

    PubMed

    Ahmed, S G; Ibrahim, U A; Hassan, A W

    2007-12-01

    In a retrospective analysis, the quantities, patterns and adequacy of blood donations made, between 1984 and 2006, at the University of Maiduguri Teaching Hospital in north-eastern Nigeria were explored and related to blood safety in the study area. The types of blood donor were reviewed and the annual increments in the number of donations made were estimated and compared with the annual increments in the numbers of in-patients managed at the study hospital. The mean annual increment in the number of blood donations (4%) fell well below the mean annual increment in in-patient numbers (11%). The blood donations received at the hospital fell into four types: voluntary, family-replacement, commercial and pre-deposit autologous donations. Over the study period, the percentage of donations falling into the voluntary and family-replacement categories fell from 31% to 5% and from 49% to 23%, respectively. These falls were matched by increases in the percentages of donations categorised as commercial and autologous, which rose from 20% to 63%, and from 1% to 9%, respectively. By the end of the study period, the quantity of blood being donated at the hospital was grossly inadequate and predominantly derived from family and commercial donors, who were found to be generally inferior, in terms of blood safety, to voluntary donors. There is an urgent need to rectify this situation by setting up a functional and national blood-transfusion service in Nigeria.

  14. Platelet and Red Blood Cell Utilization and Transfusion Independence in Umbilical Cord Blood and Allogeneic Peripheral Blood Hematopoietic Cell Transplants

    PubMed Central

    Solh, Melhem; Brunstein, Claudio; Morgan, Shanna; Weisdorf, Daniel

    2010-01-01

    Allogeneic hematopoietic cell transplantation (HCT) recipients have substantial transfusion requirements. Factors associated with increased transfusions and the extent of blood product use in umbilical cord blood (UCB) recipients are uncertain. We reviewed blood product use in 229 consecutive adult recipients of allogeneic HCT at the University of Minnesota: 147 with leukemia, 82 lymphoma or myeloma; 58% received unrelated UCB and 43% sibling donor peripheral blood stem cell (PBSC) grafts. Although neutrophil recovery was prompt (UCB median 17, range 2–45 days, and PBSC 14, range 3–34 days), only 135 of 229 (59% cumulative incidence, CI) achieved RBC independence and 157 (69%) achieved platelet independence by 6 months. Time to platelet independence was prolonged in UCB recipients (median UCB 41 vs. PBSC 14 days) and in patients who had received a prior transplant (median 48 vs. 32 days). Patients who received UCB grafts required more RBC through day 60 post HCT (mean UCB 7.8 (95% CI 6.7–8.9) vs. PBSC 5.2 (3.7–6.7) transfusions, p=0.04), and more platelet transfusions (mean 25.2 (95% CI 22.1–28.2) vs. 12.9 (9.4–16.4), p<0.01) compared to PBSC recipients. Patient receiving myeloablative (MA) conditioning required more RBC and platelet transfusions during the first 2 months post HCT compared to reduced intensity conditioning (RIC) (7.4 vs. 6.2, p=0.3 for RBC; 23.2 vs 17.5, p=0.07 for platelets). Despite prompt neutrophil engraftment, UCB recipients had delayed platelet recovery as well as more prolonged and costly blood product requirements. Enhanced approaches to accelerate multilineage engraftment could limit the transfusion-associated morbidity and costs accompanying UCB allotransplantation. PMID:20813199

  15. Blood stem cell procurement: donor safety issues.

    PubMed

    Anderlini, P; Przepiorka, D; Körbling, M; Champlin, R

    1998-06-01

    Allogeneic transplantation of rhG-CSF-mobilized peripheral blood stem cells (PBSCs) is now being increasingly performed, but safety considerations for hematologically normal PBSC donors have not been fully addressed. Experience in this area is rapidly accumulating, however, and on the basis of currently available data, a consensus is gradually emerging on several issues: (1) rhG-CSF treatment and PBSC collection seem to have an acceptable short-term safety profile in normal donors. There is a need for continued safety monitoring, however. (2) rhG-CSF doses up to 10 microg/kg/day show a consistent dose-response relationship with the mobilization (and collection) of CD34+ progenitor cells, and this dose is acceptable for routine clinical use. Whether higher doses are superior (or cost-effective) remains to be determined, and they may produce more severe side-effects. The potential risks of marked leukocytosis (arbitrarily defined as a leukocyte count of more than 70 x 10(9)/l) have been a concern, and rhG-CSF dose reduction is performed by many centers to maintain leukocyte counts below this level. (3) Transient post-donation cytopenias, involving granulocytes, lymphocytes and platelets, may occur and are at least partly related to the leukapheresis procedure. These are generally asymptomatic and self-limited; follow-up blood counts are not necessarily required. Reinfusion of autologous platelet-rich plasma should be considered for donors with expected post-donation thrombocytopenia (platelet count <80-100 x 10(9)/l). (4) Donors should meet the eligibility criteria which apply to donors of apheresis platelets, with the exception that pediatric (as well as elderly) donors may also be considered. There is insufficient information at this time to clearly establish definite contraindications for PBSC collection in a hematologically normal donor. Potential contraindications include the presence of inflammatory, autoimmune or rheumatologic disorders, as well as

  16. Quality of red blood cells isolated from umbilical cord blood stored at room temperature.

    PubMed

    Zhurova, Mariia; Akabutu, John; Acker, Jason

    2012-01-01

    Red blood cells (RBCs) from cord blood contain fetal hemoglobin that is predominant in newborns and, therefore, may be more appropriate for neonatal transfusions than currently transfused adult RBCs. Post-collection, cord blood can be stored at room temperature for several days before it is processed for stem cells isolation, with little known about how these conditions affect currently discarded RBCs. The present study examined the effect of the duration cord blood spent at room temperature and other cord blood characteristics on cord RBC quality. RBCs were tested immediately after their isolation from cord blood using a broad panel of quality assays. No significant decrease in cord RBC quality was observed during the first 65 hours of storage at room temperature. The ratio of cord blood to anticoagulant was associated with RBC quality and needs to be optimized in future. This knowledge will assist in future development of cord RBC transfusion product.

  17. Quality of Red Blood Cells Isolated from Umbilical Cord Blood Stored at Room Temperature

    PubMed Central

    Zhurova, Mariia; Akabutu, John; Acker, Jason

    2012-01-01

    Red blood cells (RBCs) from cord blood contain fetal hemoglobin that is predominant in newborns and, therefore, may be more appropriate for neonatal transfusions than currently transfused adult RBCs. Post-collection, cord blood can be stored at room temperature for several days before it is processed for stem cells isolation, with little known about how these conditions affect currently discarded RBCs. The present study examined the effect of the duration cord blood spent at room temperature and other cord blood characteristics on cord RBC quality. RBCs were tested immediately after their isolation from cord blood using a broad panel of quality assays. No significant decrease in cord RBC quality was observed during the first 65 hours of storage at room temperature. The ratio of cord blood to anticoagulant was associated with RBC quality and needs to be optimized in future. This knowledge will assist in future development of cord RBC transfusion product. PMID:24089645

  18. Red blood cell membrane fragments but not intact red blood cells promote calcium oxalate monohydrate crystal growth and aggregation.

    PubMed

    Chutipongtanate, Somchai; Thongboonkerd, Visith

    2010-08-01

    Cell membranes are thought to promote calcium oxalate kidney stone formation but to our knowledge the modulating effect of red blood cell membranes on calcium oxalate crystals has not been previously investigated. Thus, we examined the effects of red blood cell membrane fragments on calcium oxalate monohydrate and calcium oxalate dihydrate crystal growth and aggregation. Calcium oxalate monohydrate and calcium oxalate dihydrate crystals were treated with red blood cell membrane fragments or intact red blood cells from a healthy donor. Phase contrast microscopy was performed to evaluate crystal morphology and aggregation. We used ImageMaster 2D Platinum software to evaluate crystal size and spectrophotometric oxalate depletion assay to monitor crystal growth. Red blood cell membrane fragments had significant promoting activity on calcium oxalate monohydrate crystal growth with an approximately 75% increase in size and aggregation with an approximately 2.5-fold increase in aggregate number compared to the control without membrane fragments or cells. Approximately 50% of calcium oxalate monohydrate crystals were adhered by red blood cell membrane fragments. Intact red blood cells had no significant effect on calcium oxalate monohydrate crystal growth or aggregation but they could transform calcium oxalate monohydrate to calcium oxalate dihydrate crystals. Red blood cell membrane fragments and intact red blood cells had no effect on calcium oxalate dihydrate crystals. The promoting activity of red blood cell membrane fragments on calcium oxalate monohydrate crystal growth was successfully confirmed by spectrophotometric oxalate depletion assay. To our knowledge our data provide the first direct evidence that red blood cell membrane fragments are a promoting factor for calcium oxalate monohydrate crystal growth and aggregation. Thus, they may aggravate calcium oxalate stone formation. Copyright (c) 2010 American Urological Association Education and Research, Inc

  19. A microfluidic chip for direct and rapid trapping of white blood cells from whole blood

    PubMed Central

    Chen, Jingdong; Chen, Di; Yuan, Tao; Xie, Yao; Chen, Xiang

    2013-01-01

    Blood analysis plays a major role in medical and science applications and white blood cells (WBCs) are an important target of analysis. We proposed an integrated microfluidic chip for direct and rapid trapping WBCs from whole blood. The microfluidic chip consists of two basic functional units: a winding channel to mix and arrays of two-layer trapping structures to trap WBCs. Red blood cells (RBCs) were eliminated through moving the winding channel and then WBCs were trapped by the arrays of trapping structures. We fabricated the PDMS (polydimethylsiloxane) chip using soft lithography and determined the critical flow velocities of tartrazine and brilliant blue water mixing and whole blood and red blood cell lysis buffer mixing in the winding channel. They are 0.25 μl/min and 0.05 μl/min, respectively. The critical flow velocity of the whole blood and red blood cell lysis buffer is lower due to larger volume of the RBCs and higher kinematic viscosity of the whole blood. The time taken for complete lysis of whole blood was about 85 s under the flow velocity 0.05 μl/min. The RBCs were lysed completely by mixing and the WBCs were trapped by the trapping structures. The chip trapped about 2.0 × 103 from 3.3 × 103 WBCs. PMID:24404026

  20. A microfluidic chip for direct and rapid trapping of white blood cells from whole blood.

    PubMed

    Chen, Jingdong; Chen, Di; Yuan, Tao; Xie, Yao; Chen, Xiang

    2013-01-01

    Blood analysis plays a major role in medical and science applications and white blood cells (WBCs) are an important target of analysis. We proposed an integrated microfluidic chip for direct and rapid trapping WBCs from whole blood. The microfluidic chip consists of two basic functional units: a winding channel to mix and arrays of two-layer trapping structures to trap WBCs. Red blood cells (RBCs) were eliminated through moving the winding channel and then WBCs were trapped by the arrays of trapping structures. We fabricated the PDMS (polydimethylsiloxane) chip using soft lithography and determined the critical flow velocities of tartrazine and brilliant blue water mixing and whole blood and red blood cell lysis buffer mixing in the winding channel. They are 0.25 μl/min and 0.05 μl/min, respectively. The critical flow velocity of the whole blood and red blood cell lysis buffer is lower due to larger volume of the RBCs and higher kinematic viscosity of the whole blood. The time taken for complete lysis of whole blood was about 85 s under the flow velocity 0.05 μl/min. The RBCs were lysed completely by mixing and the WBCs were trapped by the trapping structures. The chip trapped about 2.0 × 10(3) from 3.3 × 10(3) WBCs.

  1. A microfluidic biochip for complete blood cell counts at the point-of-care

    PubMed Central

    Hassan, U.; Reddy, B.; Damhorst, G.; Sonoiki, O.; Ghonge, T.; Yang, C.; Bashir, R.

    2016-01-01

    Complete blood cell counts (CBCs) are one of the most commonly ordered and informative blood tests in hospitals. The results from a CBC, which typically include white blood cell (WBC) counts with differentials, red blood cell (RBC) counts, platelet counts and hemoglobin measurements, can have implications for the diagnosis and screening of hundreds of diseases and treatments. Bulky and expensive hematology analyzers are currently used as a gold standard for acquiring CBCs. For nearly all CBCs performed today, the patient must travel to either a hospital with a large laboratory or to a centralized lab testing facility. There is a tremendous need for an automated, portable point-of-care blood cell counter that could yield results in a matter of minutes from a drop of blood without any trained professionals to operate the instrument. We have developed microfluidic biochips capable of a partial CBC using only a drop of whole blood. Total leukocyte and their 3-part differential count are obtained from 10 μL of blood after on-chip lysing of the RBCs and counting of the leukocytes electrically using microfabricated platinum electrodes. For RBCs and platelets, 1 μL of whole blood is diluted with PBS on-chip and the cells are counted electrically. The total time for measurement is under 20 minutes. We demonstrate a high correlation of blood cell counts compared to results acquired with a commercial hematology analyzer. This technology could potentially have tremendous applications in hospitals at the bedside, private clinics, retail clinics and the developing world. PMID:26909365

  2. Clinical implications of non-invasive measurement of central aortic blood pressure.

    PubMed

    Stepień, Mariusz; Banach, Maciej; Jankowski, Piotr; Rysz, Jacek

    2010-11-01

    Central arterial systolic blood pressure is a very important factor in the pathophysiology of cardiovascular diseases. Central arterial pressure is a better predictor of cardiovascular risk than peripheral brachial blood pressure. Measurement of central blood pressure is useful for a diagnosis of spurious systolic hypertension in young people. Antihypertensive drugs have a different impact on central blood pressure, for example angiotensin converting enzyme inhibitors, antagonists of angiotensin II receptors, calcium channel blockers more effectively lower central blood pressure than betablockers, despite all of those drugs (including beta-blockers) having a similar impact on peripheral pressure. This mechanism may be responsible for the beneficial effect of some antihypertensive drugs on cardiovascular end points observed in clinical trials, despite a low peripheral hypotensive effect. However, further clinical trials are required to provide more evidence for the prognostic and therapeutic implications of the measurement of central blood pressure before adopting its routine application in clinical practice.

  3. Hyperspectral enhanced dark field microscopy for imaging blood cells.

    PubMed

    Verebes, Giulia Sacco; Melchiorre, Michele; Garcia-Leis, Adianez; Ferreri, Carla; Marzetti, Carla; Torreggiani, Armida

    2013-12-01

    In this work, a novel methodology based on hyperspectral imagery with enhanced Darkfield microscopy for probing and characterizing changes in blood cell components was tested. Two main categories of blood cells were analyzed, red and white blood cells. Unique spectral signatures of ordinary and most common deformed morphologies of red blood cells were identified. Moreover, examination of white blood cells allowed to characterize and differentiate active from inactive cells. The findings indicate the ability of this technique to detect changes in light scattering property of blood cells due to their morphological properties Since pathological states can alterate the discocyte shape, this preliminary, but promising application of the hyperspectral analysis to blood cells can be useful to evaluate significant correlations of blood cell spectral features in healthy and pathological conditions. The combination of the quali- and quantitative spectral signatures of hyperspectral imaging microscopy with the information of the subject health conditions may provide a new tool for clinical applications. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Primary cilia are present on human blood and bone marrow cells and mediate Hedgehog signaling.

    PubMed

    Singh, Mohan; Chaudhry, Parvesh; Merchant, Akil A

    2016-12-01

    Primary cilia are nonmotile, microtubule-based organelles that are present on the cellular membrane of all eukaryotic cells. Functional cilia are required for the response to developmental signaling pathways such as Hedgehog (Hh) and Wnt/β-catenin. Although the Hh pathway has been shown to be active in leukemia and other blood cancers, there have been no reports describing the presence of primary cilia in human blood or leukemia cells. In the present study, we show that nearly all human blood and bone marrow cells have primary cilia (97-99%). In contrast, primary cilia on AML cell lines (KG1, KG1a, and K562) were less frequent (10-36% of cells) and were often shorter and dysmorphic, with less well-defined basal bodies. Finally, we show that treatment of blood cells with the Hh pathway ligand Sonic Hedgehog (SHh) causes translocation of Smoothened (SMO) to the primary cilia and activation of Hh target genes, demonstrating that primary cilia in blood cells are functional and participate in Hh signaling. Loss of primary cilia on leukemia cells may have important implications for aberrant pathway activation and response to SMO inhibitors currently in clinical development. Copyright © 2016 ISEH - International Society for Experimental Hematology. Published by Elsevier Inc. All rights reserved.

  5. Differential effects of Tat proteins derived from HIV-1 subtypes B and recombinant CRF02_AG on human brain microvascular endothelial cells: implications for blood-brain barrier dysfunction.

    PubMed

    Woollard, Shawna M; Bhargavan, Biju; Yu, Fang; Kanmogne, Georgette D

    2014-06-01

    HIV-1 genetic differences influence viral replication and progression to AIDS. HIV-1 circulating recombinant form (CRF)02_AG is the predominant viral subtype infecting humans in West and Central Africa, but its effects on HIV neuropathogenesis are not known. In the present study, we investigated the effects of Tat proteins from HIV-1 subtype B (Tat.B) and HIV-1 CRF02_AG (Tat.AG) on primary human brain microvascular endothelial cells (HBMEC), the major component of the blood-brain barrier (BBB). Using Affymetrix GeneChip Human Gene 1.0.ST arrays, we showed that Tat.AG had minimal effects while Tat.B induced transcriptional upregulation of 90 genes in HBMEC, including proinflammatory chemokines, complement components C3, C7, and complement factor B, matrix metalloproteinases (MMP)-3, MMP-10, and MMP-12. These results were confirmed by real-time PCR. Compared with Tat.AG, Tat.B significantly increased MMP-3, MMP-10, and MMP-12 activities in HBMEC, and the MMPs tissue inhibitor of metalloproteinase-2 blocked Tat-induced increase in MMPs activity. Western blot analyses also showed that Tat increased the expression of C3 and its cleaved fragment C3b in HBMEC. These data suggest that genetic differences between HIV-1 subtypes B and CRF02_AG influence the effects of Tat proteins from these two clades on HBMEC, including molecular and cellular functions, and canonical pathways, which would affect BBB dysfunction and viral neuropathogenesis.

  6. Neurological Complications following Blood Transfusions in Sickle Cell Anemia

    PubMed Central

    Khawar, Nayaab; Kulpa, Jolanta; Bellin, Anne; Proteasa, Simona; Sundaram, Revathy

    2017-01-01

    In Sickle Cell Anemia (SCA) patient blood transfusions are an important part of treatment for stroke and its prevention. However, blood transfusions can also lead to complications such as Reversible Posterior Leukoencephalopathy Syndrome (RPLS). This brief report highlights two cases of SCA who developed such neurological complications after a blood transfusion. RLPS should be considered as the cause of neurologic finding in patients with SCA and hypertension following a blood transfusion. PMID:28127478

  7. Connexin 36 mediates blood cell flow in mouse pancreatic islets

    PubMed Central

    Short, Kurt W.; Head, W. Steve

    2013-01-01

    The insulin-secreting β-cells are contained within islets of Langerhans, which are highly vascularized. Blood cell flow rates through islets are glucose-dependent, even though there are no changes in blood cell flow within in the surrounding exocrine pancreas. This suggests a specific mechanism of glucose-regulated blood flow in the islet. Pancreatic islets respond to elevated glucose with synchronous pulses of electrical activity and insulin secretion across all β-cells in the islet. Connexin 36 (Cx36) gap junctions between islet β-cells mediate this synchronization, which is lost in Cx36 knockout mice (Cx36−/−). This leads to glucose intolerance in these mice, despite normal plasma insulin levels and insulin sensitivity. Thus, we sought to investigate whether the glucose-dependent changes in intraislet blood cell flow are also dependent on coordinated pulsatile electrical activity. We visualized and quantified blood cell flow using high-speed in vivo fluorescence imaging of labeled red blood cells and plasma. With the use of a live animal glucose clamp, blood cell flow was measured during either hypoglycemia (∼50 mg/dl) or hyperglycemia (∼300 mg/dl). In contrast to the large glucose-dependent islet blood velocity changes observed in wild-type mice, only minimal differences are observed in both Cx36+/− and Cx36−/− mice. This observation supports a novel model where intraislet blood cell flow is regulated by the coordinated electrical activity in the islet β-cells. Because Cx36 expression and function is reduced in type 2 diabetes, the resulting defect in intraislet blood cell flow regulation may also play a significant role in diabetic pathology. PMID:24326425

  8. Connexin 36 mediates blood cell flow in mouse pancreatic islets.

    PubMed

    Short, Kurt W; Head, W Steve; Piston, David W

    2014-02-01

    The insulin-secreting β-cells are contained within islets of Langerhans, which are highly vascularized. Blood cell flow rates through islets are glucose-dependent, even though there are no changes in blood cell flow within in the surrounding exocrine pancreas. This suggests a specific mechanism of glucose-regulated blood flow in the islet. Pancreatic islets respond to elevated glucose with synchronous pulses of electrical activity and insulin secretion across all β-cells in the islet. Connexin 36 (Cx36) gap junctions between islet β-cells mediate this synchronization, which is lost in Cx36 knockout mice (Cx36(-/-)). This leads to glucose intolerance in these mice, despite normal plasma insulin levels and insulin sensitivity. Thus, we sought to investigate whether the glucose-dependent changes in intraislet blood cell flow are also dependent on coordinated pulsatile electrical activity. We visualized and quantified blood cell flow using high-speed in vivo fluorescence imaging of labeled red blood cells and plasma. With the use of a live animal glucose clamp, blood cell flow was measured during either hypoglycemia (∼50 mg/dl) or hyperglycemia (∼300 mg/dl). In contrast to the large glucose-dependent islet blood velocity changes observed in wild-type mice, only minimal differences are observed in both Cx36(+/-) and Cx36(-/-) mice. This observation supports a novel model where intraislet blood cell flow is regulated by the coordinated electrical activity in the islet β-cells. Because Cx36 expression and function is reduced in type 2 diabetes, the resulting defect in intraislet blood cell flow regulation may also play a significant role in diabetic pathology.

  9. A photonic crystal hydrogel suspension array for the capture of blood cells from whole blood

    NASA Astrophysics Data System (ADS)

    Zhang, Bin; Cai, Yunlang; Shang, Luoran; Wang, Huan; Cheng, Yao; Rong, Fei; Gu, Zhongze; Zhao, Yuanjin

    2016-02-01

    Diagnosing hematological disorders based on the separation and detection of cells in the patient's blood is a significant challenge. We have developed a novel barcode particle-based suspension array that can simultaneously capture and detect multiple types of blood cells. The barcode particles are polyacrylamide (PAAm) hydrogel inverse opal microcarriers with characteristic reflection peak codes that remain stable during cell capture on their surfaces. The hydrophilic PAAm hydrogel scaffolds of the barcode particles can entrap various plasma proteins to capture different cells in the blood, with little damage to captured cells.Diagnosing hematological disorders based on the separation and detection of cells in the patient's blood is a significant challenge. We have developed a novel barcode particle-based suspension array that can simultaneously capture and detect multiple types of blood cells. The barcode particles are polyacrylamide (PAAm) hydrogel inverse opal microcarriers with characteristic reflection peak codes that remain stable during cell capture on their surfaces. The hydrophilic PAAm hydrogel scaffolds of the barcode particles can entrap various plasma proteins to capture different cells in the blood, with little damage to captured cells. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr06368j

  10. Light scattering by aggregated red blood cells

    NASA Astrophysics Data System (ADS)

    Tsinopoulos, Stephanos V.; Sellountos, Euripides J.; Polyzos, Demosthenes

    2002-03-01

    In low flow rates, red blood cells (RBCs) fasten together along their axis of symmetry and form a so-called rouleaux. The scattering of He-Ne laser light by a rouleau consisting of n (2 less-than-or-equal n less-than-or-equal 8) average-sized RBCs is investigated. The interaction problem is treated numerically by means of an advanced axisymmetric boundary element--fast Fourier transform methodology. The scattering problem of one RBC was solved first, and the results showed that the influence of the RBC's membrane on the scattering patterns is negligible. Thus the rouleau is modeled as an axisymmetric, homogeneous, low-contrast dielectric cylinder, on the surface of which appears, owing to aggregated RBCs, a periodic roughness along the direction of symmetry. The direction of the incident laser light is considered to be perpendicular to the scatterer's axis of symmetry. The differential scattering cross sections in both perpendicular and parallel scattering planes and for all the scattering angles are calculated and presented in detail.

  11. DNA methylation in white blood cells

    PubMed Central

    Delgado-Cruzata, Lissette; Vin-Raviv, Neomi; Wu, Hui Chen; Santella, Regina M

    2011-01-01

    Alterations in DNA methylation patterns, both at specific loci and overall in the genome, have been associated with many different health outcomes. In cancer and other diseases, most of these changes have been observed at the tissue level. Data on whether DNA methylation changes in white blood cells (WBC) can serve as a useful biomarker for different health outcomes are much more limited, but rapidly emerging. Epidemiologic studies have reported associations between global WBC methylation and several different cancers including cancers of the colon, bladder, stomach, breast, and head and neck, as well as schizophrenia and myelodysplastic syndrome. Evidence for WBC methylation at specific loci and disease risk is more limited, but increasing. Differences in WBC DNA methylation by selected risk factors including demographic (age, gender, race), environmental exposures (benzene, persistent organic pollutants, lead, arsenic and air pollution), and other risk factors (cigarette smoke, alcohol drinking, body size, physical activity and diet) have been observed in epidemiologic studies though the patterns are far from consistent. Challenges in inferences from the existing data are primarily due to the cross-sectional fashion and small size of most studies performed to date, as well as to the differences in results across assay type and source of DNA. Large, prospective studies will be needed to understand whether changes in risk factors are associated with changes in DNA methylation patterns, and if changes in DNA methylation patterns are associated with changes in disease endpoints. PMID:21636973

  12. 21 CFR 864.8200 - Blood cell diluent.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Blood cell diluent. 864.8200 Section 864.8200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Reagents § 864.8200 Blood cell diluent....

  13. Effect of Induced Pluripotent Stem Cell Technology in Blood Banking

    PubMed Central

    Focosi, Daniele

    2016-01-01

    Summary Population aging has imposed cost-effective alternatives to blood donations. Artificial blood is still at the preliminary stages of development, and the need for viable cells seems unsurmountable. Because large numbers of viable cells must be promptly available for clinical use, stem cell technologies, expansion, and banking represent ideal tools to ensure a regular supply. Provided key donors can be identified, induced pluripotent stem cell (iPSC) technology could pave the way to a new era in transfusion medicine, just as it is already doing in many other fields of medicine. The present review summarizes the current state of research on iPSC technology in the field of blood banking, highlighting hurdles, and promises. Significance The aging population in Western countries is causing a progressive reduction of blood donors and a constant increase of blood recipients. Because blood is the main therapeutic option to treat acute hemorrhage, cost-effective alternatives to blood donations are being actively investigated. The enormous replication capability of induced pluripotent stem cells and their promising results in many other fields of medicine could be an apt solution to produce the large numbers of viable cells required in transfusion and usher in a new era in transfusion medicine. The present report describes the potentiality, technological hurdles, and promises of induced pluripotent stem cells to generate red blood cells by redifferentiation. PMID:26819256

  14. Hormones that Stimulate the Growth of Blood Cells.

    ERIC Educational Resources Information Center

    Golde, David W.; Gasson, Judith C.

    1988-01-01

    Describes the nature and action of hematopoietic proteins which regulate the production of specific sets of blood cells. Discusses the production of these hematopoietins by recombinant-DNA methods in an effort to enable physicians to treat patients by eliciting production of specific types of blood cells. (CW)

  15. Hormones that Stimulate the Growth of Blood Cells.

    ERIC Educational Resources Information Center

    Golde, David W.; Gasson, Judith C.

    1988-01-01

    Describes the nature and action of hematopoietic proteins which regulate the production of specific sets of blood cells. Discusses the production of these hematopoietins by recombinant-DNA methods in an effort to enable physicians to treat patients by eliciting production of specific types of blood cells. (CW)

  16. Computational Biomechanics of Human Red Blood Cells in Hematological Disorders.

    PubMed

    Li, Xuejin; Li, He; Chang, Hung-Yu; Lykotrafitis, George; Em Karniadakis, George

    2017-02-01

    We review recent advances in multiscale modeling of the biomechanical characteristics of red blood cells (RBCs) in hematological diseases, and their relevance to the structure and dynamics of defective RBCs. We highlight examples of successful simulations of blood disorders including malaria and other hereditary disorders, such as sickle-cell anemia, spherocytosis, and elliptocytosis.

  17. Oscillation dynamics of embolic microspheres in flows with red blood cell suspensions

    NASA Astrophysics Data System (ADS)

    Das, Tamal; Carugo, Dario; Zhang, Xunli; Chakraborty, Suman

    2012-12-01

    Dynamic nature of particle motion in blood flow is an important determinant of embolization based cancer therapy. Yet, the manner in which the presence of high volume fraction of red blood cells influences the particle dynamics remains unknown. Here, by investigating the motions of embolic microspheres in pressure-driven flows of red blood cell suspensions through capillaries, we illustrate unique oscillatory trends in particle trajectories, which are not observable in Newtonian fluid flows. Our investigation reveals that such oscillatory behavior essentially manifests when three simultaneous conditions, namely, the Reynolds number beyond a threshold limit, degree of confinement beyond a critical limit, and high hematocrit level, are fulfilled simultaneously. Given that these conditions are extremely relevant to fluid dynamics of blood or polymer flow, the observations reported here bear significant implications on embolization based cancer treatment as well as for complex multiphase fluidics involving particles.

  18. Red blood cells in sports: effects of exercise and training on oxygen supply by red blood cells.

    PubMed

    Mairbäurl, Heimo

    2013-01-01

    During exercise the cardiovascular system has to warrant substrate supply to working muscle. The main function of red blood cells in exercise is the transport of O2 from the lungs to the tissues and the delivery of metabolically produced CO2 to the lungs for expiration. Hemoglobin also contributes to the blood's buffering capacity, and ATP and NO release from red blood cells contributes to vasodilation and improved blood flow to working muscle. These functions require adequate amounts of red blood cells in circulation. Trained athletes, particularly in endurance sports, have a decreased hematocrit, which is sometimes called "sports anemia." This is not anemia in a clinical sense, because athletes have in fact an increased total mass of red blood cells and hemoglobin in circulation relative to sedentary individuals. The slight decrease in hematocrit by training is brought about by an increased plasma volume (PV). The mechanisms that increase total red blood cell mass by training are not understood fully. Despite stimulated erythropoiesis, exercise can decrease the red blood cell mass by intravascular hemolysis mainly of senescent red blood cells, which is caused by mechanical rupture when red blood cells pass through capillaries in contracting muscles, and by compression of red cells e.g., in foot soles during running or in hand palms in weightlifters. Together, these adjustments cause a decrease in the average age of the population of circulating red blood cells in trained athletes. These younger red cells are characterized by improved oxygen release and deformability, both of which also improve tissue oxygen supply during exercise.

  19. Red blood cells in sports: effects of exercise and training on oxygen supply by red blood cells

    PubMed Central

    Mairbäurl, Heimo

    2013-01-01

    During exercise the cardiovascular system has to warrant substrate supply to working muscle. The main function of red blood cells in exercise is the transport of O2 from the lungs to the tissues and the delivery of metabolically produced CO2 to the lungs for expiration. Hemoglobin also contributes to the blood's buffering capacity, and ATP and NO release from red blood cells contributes to vasodilation and improved blood flow to working muscle. These functions require adequate amounts of red blood cells in circulation. Trained athletes, particularly in endurance sports, have a decreased hematocrit, which is sometimes called “sports anemia.” This is not anemia in a clinical sense, because athletes have in fact an increased total mass of red blood cells and hemoglobin in circulation relative to sedentary individuals. The slight decrease in hematocrit by training is brought about by an increased plasma volume (PV). The mechanisms that increase total red blood cell mass by training are not understood fully. Despite stimulated erythropoiesis, exercise can decrease the red blood cell mass by intravascular hemolysis mainly of senescent red blood cells, which is caused by mechanical rupture when red blood cells pass through capillaries in contracting muscles, and by compression of red cells e.g., in foot soles during running or in hand palms in weightlifters. Together, these adjustments cause a decrease in the average age of the population of circulating red blood cells in trained athletes. These younger red cells are characterized by improved oxygen release and deformability, both of which also improve tissue oxygen supply during exercise. PMID:24273518

  20. Isolation of mesenchymal stem cells from equine umbilical cord blood

    PubMed Central

    Koch, Thomas G; Heerkens, Tammy; Thomsen, Preben D; Betts, Dean H

    2007-01-01

    Background There are no published studies on stem cells from equine cord blood although commercial storage of equine cord blood for future autologous stem cell transplantations is available. Mesenchymal stem cells (MSC) have been isolated from fresh umbilical cord blood of humans collected non-invasively at the time of birth and from sheep cord blood collected invasively by a surgical intrauterine approach. Mesenchymal stem cells isolation percentage from frozen-thawed human cord blood is low and the future isolation percentage of MSCs from cryopreserved equine cord blood is therefore expectedly low. The hypothesis of this study was that equine MSCs could be isolated from fresh whole equine cord blood. Results Cord blood was collected from 7 foals immediately after foaling. The mononuclear cell fraction was isolated by Ficoll density centrifugation and cultured in a DMEM low glucose based media at 38.5°C in humidified atmosphere containing 5% CO2. In 4 out of 7 samples colonies with MSC morphology were observed. Cellular morphology varied between monolayers of elongated spindle-shaped cells to layered cell clusters of cuboidal cells with shorter cytoplasmic extensions. Positive Alizarin Red and von Kossa staining as well as significant calcium deposition and alkaline phosphatase activity confirmed osteogenesis. Histology and positive Safranin O staining of matrix glycosaminoglycans illustrated chondrogenesis. Oil Red O staining of lipid droplets confirmed adipogenesis. Conclusion We here report, for the first time, the isolation of mesenchymal-like stem cells from fresh equine cord blood and their differentiation into osteocytes, chondrocytes and adipocytes. This novel isolation of equine cord blood MSCs and their preliminary in vitro differentiation positions the horse as the ideal pre-clinical animal model for proof-of-principle studies of cord blood derived MSCs. PMID:17537254

  1. Isolation of mesenchymal stem cells from equine umbilical cord blood.

    PubMed

    Koch, Thomas G; Heerkens, Tammy; Thomsen, Preben D; Betts, Dean H

    2007-05-30

    There are no published studies on stem cells from equine cord blood although commercial storage of equine cord blood for future autologous stem cell transplantations is available. Mesenchymal stem cells (MSC) have been isolated from fresh umbilical cord blood of humans collected non-invasively at the time of birth and from sheep cord blood collected invasively by a surgical intrauterine approach. Mesenchymal stem cells isolation percentage from frozen-thawed human cord blood is low and the future isolation percentage of MSCs from cryopreserved equine cord blood is therefore expectedly low. The hypothesis of this study was that equine MSCs could be isolated from fresh whole equine cord blood. Cord blood was collected from 7 foals immediately after foaling. The mononuclear cell fraction was isolated by Ficoll density centrifugation and cultured in a DMEM low glucose based media at 38.5 degrees C in humidified atmosphere containing 5% CO2. In 4 out of 7 samples colonies with MSC morphology were observed. Cellular morphology varied between monolayers of elongated spindle-shaped cells to layered cell clusters of cuboidal cells with shorter cytoplasmic extensions. Positive Alizarin Red and von Kossa staining as well as significant calcium deposition and alkaline phosphatase activity confirmed osteogenesis. Histology and positive Safranin O staining of matrix glycosaminoglycans illustrated chondrogenesis. Oil Red O staining of lipid droplets confirmed adipogenesis. We here report, for the first time, the isolation of mesenchymal-like stem cells from fresh equine cord blood and their differentiation into osteocytes, chondrocytes and adipocytes. This novel isolation of equine cord blood MSCs and their preliminary in vitro differentiation positions the horse as the ideal pre-clinical animal model for proof-of-principle studies of cord blood derived MSCs.

  2. Red blood cells and thrombin generation in sickle cell disease.

    PubMed

    Whelihan, Matthew F; Lim, Ming Y; Key, Nigel S

    2014-05-01

    The prothrombotic nature of sickle cell disease (SCD) is evidenced by the chronically elevated levels of almost all coagulation activation biomarkers, and an increased incidence of certain thrombotic events, including venous thromboembolism. Numerous studies have attempted to define the extent and elucidate the mechanism of the observed increase in thrombin generation in SCD patients in vivo. In general, these studies were performed using thrombin generation assays in platelet poor or platelet rich plasma and showed little difference in endogenous thrombin potential between the SCD cohort and healthy matched controls. In SCD, erythrocytes and monocytes have been demonstrated to exhibit procoagulant characteristics. Thus, the absence of these cellular components in standard thrombin generation assays may fail to reflect global hypercoagulability in the whole blood of patients with SCD. We were therefore surprised to see no difference in net thrombin generation in tissue factor-initiated initiated clotting of whole blood from patients with SCD. However, we are continuing to reconcile these seemingly disparate observations by slight modifications of the whole blood model that include alternative coagulation triggers and a re-examination of the net thrombin generation when the protein/protein S system is simultaneously interrogated.

  3. The counting of native blood cells by digital microscopy

    NASA Astrophysics Data System (ADS)

    Torbin, S. O.; Doubrovski, V. A.; Zabenkov, I. V.; Tsareva, O. E.

    2017-03-01

    An algorithm for photographic images processing of blood samples in its native state was developed to determine the concentration of erythrocytes, leukocytes and platelets without individual separate preparation of cells' samples. Special "photo templates" were suggested to use in order to identify red blood cells. The effect of "highlighting" of leukocytes, which was found by authors, was used to increase the accuracy of this type of cells counting. Finally to raise the resolution of platelets from leukocytes the areas of their photo images were used, but not their sizes. It is shown that the accuracy of cells counting for native blood samples may be comparable with the accuracy of similar studies for smears. At the same time the proposed native blood analysis simplifies greatly the procedure of sample preparation in comparison to smear, permits to move from the detection of blood cells ratio to the determination of their concentrations in the sample.

  4. [Regularity of sugar-uptake in human red blood cells].

    PubMed

    Quan, Guo-Bo; Lü, Cui-Cui; Liu, Min-Xia; Hu, Wen-Bo; Wang, Yan; Han, Ying

    2006-06-01

    Lyophilization of human red blood cells has important significance in clinical application. Some sugars, especially trehalose, can be more tolerant of some organism or cells to dry environments, But, how to bring sugars into cells is a challenge. This study was aimed to investigate the regularity of sugar-uptake in human red blood cells. The absorption rate of trehalose and glucose in red blood cells, free hemoglobin level and erythrocyte deformation index were determined at different incubation temperature (4, 25 and 37 degrees C), different sugar concentration (0, 0.2, 0.4, 0.6, 0.8 and 1 mol/L) and different incubation time (1, 3, 5, 7 and 9 hours). The results showed that with increase of temperature and extracellular sugar concentration, the uptake of sugar in red blood cells also increased, the intracellular trehalose and glucose concentrations were over 30 mmol/L and 40 mmol/L respectively. The effects of incubation time on uptake of trehalose and glucose were different. With prolonging of incubation time, the uptake of trehalose showed firstly increase and then decrease, however, the uptake of glucose showed a constant increase. But the loading process had side-effect on free hemoglobin and maximum deformation index (MAXDI) of red blood cells, especially for trehalose, which mainly come from high osmotic pressure. It is concluded that the uptake of sugars in red blood cells is closely dependent on incubation temperature, extracellular sugar concentration and incubation time. In certain condition, the efficiency of sugar uptake is very high, but this process also damages red blood cells so as to affect the application of sugars in lyophilization of red blood cells. The research in the future should focus on how to deal with the relation between cell injury and uptake efficiency of sugar in red blood cells.

  5. Microfluidic impedance cytometry of tumour cells in blood

    PubMed Central

    Spencer, Daniel; Morgan, Hywel

    2014-01-01

    The dielectric properties of tumour cells are known to differ from normal blood cells, and this difference can be exploited for label-free separation of cells. Conventional measurement techniques are slow and cannot identify rare circulating tumour cells (CTCs) in a realistic timeframe. We use high throughput single cell microfluidic impedance cytometry to measure the dielectric properties of the MCF7 tumour cell line (representative of CTCs), both as pure populations and mixed with whole blood. The data show that the MCF7 cells have a large membrane capacitance and size, enabling clear discrimination from all other leukocytes. Impedance analysis is used to follow changes in cell viability when cells are kept in suspension, a process which can be understood from modelling time-dependent changes in the dielectric properties (predominantly membrane conductivity) of the cells. Impedance cytometry is used to enumerate low numbers of MCF7 cells spiked into whole blood. Chemical lysis is commonly used to remove the abundant erythrocytes, and it is shown that this process does not alter the MCF7 cell count or change their dielectric properties. Combining impedance cytometry with magnetic bead based antibody enrichment enables MCF7 cells to be detected down to 100 MCF7 cells in 1 ml whole blood, a log 3.5 enrichment and a mean recovery of 92%. Microfluidic impedance cytometry could be easily integrated within complex cell separation systems for identification and enumeration of specific cell types, providing a fast in-line single cell characterisation method. PMID:25553198

  6. Microvascular blood flow resistance: Role of red blood cell migration and dispersion.

    PubMed

    Katanov, Dinar; Gompper, Gerhard; Fedosov, Dmitry A

    2015-05-01

    Microvascular blood flow resistance has a strong impact on cardiovascular function and tissue perfusion. The flow resistance in microcirculation is governed by flow behavior of blood through a complex network of vessels, where the distribution of red blood cells across vessel cross-sections may be significantly distorted at vessel bifurcations and junctions. In this paper, the development of blood flow and its resistance starting from a dispersed configuration of red blood cells is investigated in simulations for different hematocrit levels, flow rates, vessel diameters, and aggregation interactions between red blood cells. Initially dispersed red blood cells migrate toward the vessel center leading to the formation of a cell-free layer near the wall and to a decrease of the flow resistance. The development of cell-free layer appears to be nearly universal when scaled with a characteristic shear rate of the flow. The universality allows an estimation of the length of a vessel required for full flow development, lc ≲ 25D, for vessel diameters in the range 10 μm < D < 100 μm. Thus, the potential effect of red blood cell dispersion at vessel bifurcations and junctions on the flow resistance may be significant in vessels which are shorter or comparable to the length lc. Aggregation interactions between red blood cells generally lead to a reduction of blood flow resistance. The simulations are performed using the same viscosity for both external and internal fluids and the RBC membrane viscosity is not considered; however, we discuss how the viscosity contrast may affect the results. Finally, we develop a simple theoretical model which is able to describe the converged cell-free-layer thickness at steady-state flow with respect to flow rate. The model is based on the balance between a lift force on red blood cells due to cell-wall hydrodynamic interactions and shear-induced effective pressure due to cell-cell interactions in flow. We expect that these results can

  7. Relation between stable isotope ratios in human red blood cells and hair: implications for using the nitrogen isotope ratio of hair as a biomarker of eicosapentaenoic acid and docosahexaenoic acid1234

    PubMed Central

    Nash, Sarah H; Kristal, Alan R; Boyer, Bert B; King, Irena B; Metzgar, Jordan S

    2009-01-01

    Background: The nitrogen isotope ratio (expressed as δ15N) of red blood cells (RBCs) is highly correlated with the RBC long-chain ω−3 (n−3) fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in Yup'ik Eskimos. Because δ15N can also be measured in hair samples, it could provide a noninvasive, retrospective biomarker for EPA and DHA intakes. Objectives: We investigated the agreement between δ15N in hair and RBCs and then evaluated the relations between hair δ15N and RBC EPA and DHA. We also assessed the agreement in carbon isotope ratios (δ13C) between hair and RBCs, because δ13C has been proposed as a dietary biomarker in other populations. Design: We assessed relations between hair and RBC δ15N and δ13C in a community-based sample of 144 Yup'ik Eskimos and examined the correlations between δ15N and RBC EPA and DHA in a subset of these participants (n = 44). Results: We showed a 1:1 relation with good agreement between hair and RBC δ15N (r = 0.91) and δ13C (r = 0.87). Hair isotope ratios were greater than RBC ratios by 1.5‰ for δ15N and by 2.3‰ for δ13C. There were strong correlations between hair δ15N and RBC EPA and DHA (r = 0.83 and 0.84, respectively). Conclusions: These results support the use of hair δ15N values as a biomarker of EPA and DHA intakes. Because hair collection is noninvasive and the samples require no special processing, studies of EPA and DHA intakes in large populations could use biomarkers rather than self-reports to assess these fatty acids. PMID:19864410

  8. Rheology of red blood cell aggregation by computer simulation

    NASA Astrophysics Data System (ADS)

    Liu, Yaling; Liu, Wing Kam

    2006-12-01

    The aggregation of red blood cells (RBC) induced by the interactions between RBCs is a dominant factor of the in vitro rheological properties of blood, and existing models of blood do not contain full cellular information. In this work, we introduce a new three-dimensional model that couples Navier-Stokes equations with cell interactions to investigate RBC aggregation and its effect on blood rheology. It consists of a depletion mediated aggregation model to describe the interactions of RBCs and an immersed continuum model to track the deformation/motion of RBCs in blood plasma. To overcome the large deformation of RBCs, the meshfree method is used to model the RBCs. Three important phenomena in blood rheology are successfully captured and studied via this approach: the shear rate dependence of blood viscosity, the influence of cell rigidity on blood viscosity, and the Fahraeus-Lindqvist effect. As a microscopic illustration of the shear-rate dependence of the blood's viscoelasticity, the disaggregation of an RBC rouleau at shear rates varying between 0.125 and 24 s -1 is modeled. Lower RBC deformability and higher shear rates above 0.5 s -1 are found to facilitate disaggregation. The effective viscosities at different shear rates and for cells with different deformabilities are simulated. The numerical results are shown to agree with the reported experimental measurements. The Fahraeus-Lindqvist effect is, for the first time, studied through three-dimensional numerical simulations of blood flow through tubes with different diameters and is shown to be directly linked to axial-migration of deformable cells. This study shows that cell-cell interaction and cell deformability have significant effects on blood rheology in capillaries.

  9. Fresenius AS.TEC204 blood cell separator.

    PubMed

    Sugai, Mikiya

    2003-02-01

    Fresenius AS.TEC204 is a third-generation blood cell separator that incorporates the continuous centrifugal separation method and automatic control of the cell separation process. Continuous centrifugation separates cell components according to their specific gravity, and different cell components are either harvested or eliminated as needed. The interface between the red blood cell and plasma is optically detected, and the Interface Control (IFC) cooperates with different pumps, monitors and detectors to harvest required components automatically. The system is composed of three major sections; the Front Panel Unit; the Pump Unit, and the Centrifuge Unit. This unit can be used for a wide variety of clinical applications including collection of platelets, peripheral blood stem cells, bone marrow stem cells, granulocytes, mononuclear cells, and exchange of plasma or red cells, and for plasma treatment.

  10. Calf blood pressure: clinical implications and correlations with arm blood pressure in infants and young children.

    PubMed

    Crapanzano, M S; Strong, W B; Newman, I R; Hixon, R L; Casal, D; Linder, C W

    1996-02-01

    Indirect measurement of lower extremity blood pressure is often used in the clinical setting, although normative data after the newborn period are not readily available. Indirect blood pressure (BP) measurement was obtained in the right arms and right calves of 148 healthy infants and young children 2 weeks to 3 years of age. All measurements were made using an oscillometric device. The infants and children are quiet or asleep and in the supine position. A BP cuff of proper size was chosen. Three measurements were made in both extremities; the average of the second and third measurements was used for all analyses. Age correlated better with calf systolic blood pressure (SBPc) than with arm SBP (SBPa) (r = .52 vs .17). Calf diastolic blood pressure (DBPc) and calf mean blood pressure (MBPc) correlated moderately poorly with age (r = .37 and .39, respectively). There was no order effect. SBPc correlated best with height (r = .53), then age (r = .52), and, finally, weight (r = .51). The correlation between BPc and BPa was moderately low. The correlation of SBPc with SBPa was r = .46; that of DBPc with DBPa was r = .37; and that of MBPc with MBPa was r = .41. From birth to 6 months, SBPc was slightly lower than SBPa (1 to 3 mm Hg). SBPc increased linearly relative to SBPa and began to exceed SBPa at 6 months of age. The pattern of DBP and MBP was similar. Wide variability of blood pressure parameters was noted between the infants and children at all ages. Reference data are presented for BPc and the difference between BPc and BPa in healthy infants and children from 2 weeks to 3 years of age. BPc is not equivalent to BPa and should not be arbitrarily substituted. Because of the wide variability among healthy infants and children, SBPc measurements should be interpreted with caution when evaluating for coarctation of the aorta.

  11. Mutation assays involving blood cells that metabolize toxic substances

    DOEpatents

    Crespi, Charles L.; Thilly, William G.

    1985-01-01

    A line of human blood cells which have high levels of oxidative activity (such as oxygenase, oxidase, peroxidase, and hydroxylase activity) is disclosed. Such cells grow in suspension culture, and are useful to determine the mutagenicity of xenobiotic substances that are metabolized into toxic or mutagenic substances. Mutation assays using these cells, and other cells with similar characteristics, are also disclosed.

  12. Heart rate and blood pressure: any possible implications for management of hypertension?

    PubMed

    Reule, Scott; Drawz, Paul E

    2012-12-01

    Hypertension is a common clinical problem and a major risk factor for cardiovascular disease and stroke. Elevated heart rate is associated with elevated blood pressure, increased risk for hypertension, and, among hypertensives, increased risk for cardiovascular disease. Despite these important relationships, heart rate is generally not a major consideration in choosing antihypertensive medications. In part, this is due to a lack of evidence supporting heart rate lowering as a therapeutic strategy in hypertension. Additionally, while there is a positive correlation between heart rate and peripheral blood pressure, there is an inverse relationship between heart rate and central blood pressure. The use of antihypertensive medications, specifically medications that affect heart rate, may not reliably reduce central blood pressure to a similar extent as observed peripherally. We review the relationship between heart rate and peripheral and central blood pressure, with a focus on the implications for chronotropic therapy in hypertension.

  13. Effects of helicopter transport on red blood cell components

    PubMed Central

    Otani, Taiichi; Oki, Ken-ichi; Akino, Mitsuaki; Tamura, Satoru; Naito, Yuki; Homma, Chihiro; Ikeda, Hisami; Sumita, Shinzou

    2012-01-01

    Background There are no reported studies on whether a helicopter flight affects the quality and shelf-life of red blood cells stored in mannitol-adenine-phosphate. Materials and methods Seven days after donation, five aliquots of red blood cells from five donors were packed into an SS-BOX-110 container which can maintain the temperature inside the container between 2 °C and 6 °C with two frozen coolants. The temperature of an included dummy blood bag was monitored. After the box had been transported in a helicopter for 4 hours, the red blood cells were stored again and their quality evaluated at day 7 (just after the flight), 14, 21 and 42 after donation. Red blood cell quality was evaluated by measuring adenosine triphosphate, 2,3-diphosphoglycerate, and supernatant potassium, as well as haematocrit, intracellular pH, glucose, supernatant haemoglobin, and haemolysis rate at the various time points. Results During the experiment the recorded temperature remained between 2 and 6 °C. All data from the red blood cells that had undergone helicopter transportation were the same as those from a control group of red blood cell samples 7 (just after the flight), 14, 21, and 42 days after the donation. Only supernatant Hb and haemolysis rate 42 days after the donation were slightly increased in the helicopter-transported group of red blood cell samples. All other parameters at 42 days after donation were the same in the two groups of red blood cells. Discussion These results suggest that red blood cells stored in mannitol-adenine-phosphate are not significantly affected by helicopter transportation. The differences in haemolysis by the end of storage were small and probably not of clinical significance. PMID:22153688

  14. Effects of helicopter transport on red blood cell components.

    PubMed

    Otani, Taiichi; Oki, Ken-ichi; Akino, Mitsuaki; Tamura, Satoru; Naito, Yuki; Homma, Chihiro; Ikeda, Hisami; Sumita, Shinzou

    2012-01-01

    There are no reported studies on whether a helicopter flight affects the quality and shelf-life of red blood cells stored in mannitol-adenine-phosphate. Seven days after donation, five aliquots of red blood cells from five donors were packed into an SS-BOX-110 container which can maintain the temperature inside the container between 2 °C and 6 °C with two frozen coolants. The temperature of an included dummy blood bag was monitored. After the box had been transported in a helicopter for 4 hours, the red blood cells were stored again and their quality evaluated at day 7 (just after the flight), 14, 21 and 42 after donation. Red blood cell quality was evaluated by measuring adenosine triphosphate, 2,3-diphosphoglycerate, and supernatant potassium, as well as haematocrit, intracellular pH, glucose, supernatant haemoglobin, and haemolysis rate at the various time points. During the experiment the recorded temperature remained between 2 and 6 °C. All data from the red blood cells that had undergone helicopter transportation were the same as those from a control group of red blood cell samples 7 (just after the flight), 14, 21, and 42 days after the donation. Only supernatant Hb and haemolysis rate 42 days after the donation were slightly increased in the helicopter-transported group of red blood cell samples. All other parameters at 42 days after donation were the same in the two groups of red blood cells. These results suggest that red blood cells stored in mannitol-adenine-phosphate are not significantly affected by helicopter transportation. The differences in haemolysis by the end of storage were small and probably not of clinical significance.

  15. Modification of red blood cells for laboratory quality control use.

    PubMed

    Henry, Stephen M

    2009-11-01

    This review describes the current state-of-the-art with respect to the modification of red blood cells for creating quality controls for use in immunohaematology. The author has identified five technologies able to create modified red blood cells potentially suitable for use in quality control. Two of the technologies use enzymes, glycosidases or glycosyltransferases, to modify red blood cells and create ABO quality control cells. A third technology uses polyethylene glycol to reduce antigen expression by masking epitopes, whereas a fourth technology is speculative and involves the in-vitro generation of genetically modified erythroid cells. None of these four technologies are in routine use to make commercially available quality controls. A fifth commercially available technology creates quality controls by adding synthetic blood group A and B antigens (FSLs) to group O red blood cells, creating what are referred to as 'kodecytes'. This technology is also being used to add blood group peptides onto red cells for use in the future in a range of diagnostic applications. Transducing cell-derived erythroid populations with blood group encoding or silencing vectors, and the use of FSLs to create kodecytes, are two technologies with the potential to provide quality controls for laboratory use.

  16. Models for the Red Blood Cell Lifespan

    PubMed Central

    Shrestha, Rajiv P.; Horowitz, Joseph; Hollot, Christopher V.; Germain, Michael J.; Widness, John A.; Mock, Donald M.; Veng-Pedersen, Peter; Chait, Yossi

    2016-01-01

    The lifespan of red blood cells (RBCs) plays an important role in the study and interpretation of various clinical conditions. Yet, confusion about the meanings of fundamental terms related to cell survival and their quantification still exists in the literature. To address these issues, we started from a compartmental model of RBC populations based on an arbitrary full lifespan distribution, carefully defined the residual lifespan, current age, and excess lifespan of the RBC population, and then derived the distributions of these parameters. For a set of residual survival data from biotin-labeled RBCs, we fit models based on Weibull, gamma, and lognormal distributions, using nonlinear mixed effects (NLME) modeling and parametric bootstrapping. From the estimated Weibull, gamma, and lognormal parameters we computed the respective population mean full lifespans (95% confidence interval): 115.60 (109.17–121.66), 116.71 (110.81–122.51), and 116.79 (111.23–122.75) days together with the standard deviations of the full lifespans: 24.77 (20.82–28.81), 24.30 (20.53–28.33), and 24.19 (20.43–27.73). We then estimated the 95th percentiles of the lifespan distributions (a surrogate for the maximum lifespan): 153.95 (150.02–158.36), 159.51 (155.09–164.00), and 160.40 (156.00–165.58) days, the mean current ages (or the mean residual lifespans): 60.45 (58.18–62.85), 60.82 (58.77–63.33), and 57.26 (54.33–60.61) days, and the residual half-lives: 57.97 (54.96–60.90), 58.36 (55.45–61.26), and 58.40 (55.62–61.37) days, for the Weibull, gamma, and lognormal models respectively. Corresponding estimates were obtained for the individual subjects. The three models provide equally excellent goodness-of-fit, reliable estimation, and physiologically plausible values of the directly interpretable RBC survival parameters. PMID:27039311

  17. Models for the red blood cell lifespan.

    PubMed

    Shrestha, Rajiv P; Horowitz, Joseph; Hollot, Christopher V; Germain, Michael J; Widness, John A; Mock, Donald M; Veng-Pedersen, Peter; Chait, Yossi

    2016-06-01

    The lifespan of red blood cells (RBCs) plays an important role in the study and interpretation of various clinical conditions. Yet, confusion about the meanings of fundamental terms related to cell survival and their quantification still exists in the literature. To address these issues, we started from a compartmental model of RBC populations based on an arbitrary full lifespan distribution, carefully defined the residual lifespan, current age, and excess lifespan of the RBC population, and then derived the distributions of these parameters. For a set of residual survival data from biotin-labeled RBCs, we fit models based on Weibull, gamma, and lognormal distributions, using nonlinear mixed effects modeling and parametric bootstrapping. From the estimated Weibull, gamma, and lognormal parameters we computed the respective population mean full lifespans (95 % confidence interval): 115.60 (109.17-121.66), 116.71 (110.81-122.51), and 116.79 (111.23-122.75) days together with the standard deviations of the full lifespans: 24.77 (20.82-28.81), 24.30 (20.53-28.33), and 24.19 (20.43-27.73). We then estimated the 95th percentiles of the lifespan distributions (a surrogate for the maximum lifespan): 153.95 (150.02-158.36), 159.51 (155.09-164.00), and 160.40 (156.00-165.58) days, the mean current ages (or the mean residual lifespans): 60.45 (58.18-62.85), 60.82 (58.77-63.33), and 57.26 (54.33-60.61) days, and the residual half-lives: 57.97 (54.96-60.90), 58.36 (55.45-61.26), and 58.40 (55.62-61.37) days, for the Weibull, gamma, and lognormal models respectively. Corresponding estimates were obtained for the individual subjects. The three models provide equally excellent goodness-of-fit, reliable estimation, and physiologically plausible values of the directly interpretable RBC survival parameters.

  18. Quantification of red blood cells using atomic force microscopy.

    PubMed

    O'Reilly, M; McDonnell, L; O'Mullane, J

    2001-01-01

    For humans the sizes and shapes of their red blood cells are important indicators of well being. In this study, the feasibility of using the atomic force microscope (AFM) to provide the sizes and shapes of red blood cells has been investigated. An immobilisation procedure has been developed that enabled red blood cells to be reliably imaged by contact AFM in air. The shapes of the red blood cells were readily apparent in the AFM images. Various cell quantification parameters were investigated, including thickness, width, surface area and volume. Excellent correlation was found between the AFM-derived immobilised mean cell volume (IMCV) parameter and the mean cell volume (MCV) parameter used in current haematological practice. The correlation between MCV and IMCV values has validated the immobilisation procedure by demonstrating that the significant cell shrinkage that occurs during immobilisation and drying does not introduce quantification artifacts. Reliable IMCV values were obtained by quantifying 100 red blood cells and this typically required 3-5 AFM images of 100 microm x 100 microm area. This work has demonstrated that the AFM can provide in a single test the red blood cell size and shape data needed in the assessment of human health.

  19. Induction of apoptosis in glioma cells requires cell-to-cell contact with human umbilical cord blood stem cells.

    PubMed

    Gondi, Christopher S; Gogineni, Venkateswara R; Chetty, Chandramu; Dasari, Venkata R; Gorantla, Bharathi; Gujrati, Meena; Dinh, Dzung H; Rao, Jasti S

    2010-05-01

    We have previously demonstrated the multipotent nature of human umbilical cord blood stem cells (hUCB). In this study, we have attempted to show the use of hUCB in glioma therapy. We used hUCB enriched in CD44 and CD133 cells for our studies and observed that glioma cells co-cultured with hUCB undergo apoptosis. To prove the role of cell-to-cell contact in the induction of apoptotic events, we used a modified 0.22 microm Boyden's chamber where the upper surface was used to culture glioma cells (SNB19 or U87) or xenografts (4910 or 5310) and the lower surface to culture hUCB. TUNEL assay was carried out to determine the degree of apoptotic induction and we observed that glioma or xenograft cells co-cultured with hUCB had a higher number of TUNEL-positive characteristics (63+/-6%) compared to the controls. Further, we co-cultured glioma cells labeled with lipophilic green fluorescent dye and hUCB labeled with lipophilic red fluorescent dye. FACS analysis of cells collected from the upper and lower surfaces revealed that glioma cells had taken up red fluorescent dye from the stem cells (70+/-3%) when compared to glioma cells co-cultured with fibroblast cells (15+/-4%). The apoptotic events in the glioma and xenograft cells co-cultured with hUCB were also confirmed by Western blot analysis for the cleavage of PARP and activation of caspase 8. In addition, elevated levels of CHK-2 levels and downregulation of MAP2K1 were observed in glioma cells co-cultured with hUCB indicating the DNA damage and decrease in cell survival. Nude mice, intracranially implanted with luciferase-expressing U87 cells followed by implantation of hUCB or human fibroblast cells showed retardation of intracranial tumors in hUCB-implanted mice. Taken together, these results demonstrate that hUCB have therapeutic potential with possible clinical implications.

  20. High blood pressure in children: clinical and health policy implications.

    PubMed

    Falkner, Bonita; Lurbe, Empar; Schaefer, Franz

    2010-04-01

    Hypertension is a global problem, affecting both developed and developing nations. In addition to being a major cause of morbidity and mortality, hypertension places a heavy burden on health care systems, families, and society as a whole. Despite evidence of an increasing prevalence of hypertension among youth, the consequences of early onset are poorly established and often overlooked. Childhood hypertension is often asymptomatic and easily missed, even by health professionals. Target organ damage is detectable in children and adolescents, however, and hypertension continues into adulthood. Additional strategies to improve cardiovascular health among children and adolescents are needed, including methods to achieve healthy lifestyles at home and in school, improved systems for diagnosis, and research on mechanisms and timing of interventions. The burden of hypertension in the young will continue to grow unless it is given the attention it deserves by policy makers, health care providers, schools, parents, and society. This report aims to increase awareness of the problem of hypertension in childhood. Recent reports on prevalence and target organ injury are discussed and health policy initiatives to improve blood pressure control are proposed.

  1. Origins of circulating endothelial cells and endothelial outgrowth from blood

    PubMed Central

    Lin, Yi; Weisdorf, Daniel J.; Solovey, Anna; Hebbel, Robert P.

    2000-01-01

    Normal adults have a small number of circulating endothelial cells (CEC) in peripheral blood, and endothelial outgrowth has been observed from cultures of blood. In this study we seek insight into the origins of CEC and endothelial outgrowth from cultures of blood. Fluorescence in situ hybridization analysis of blood samples from bone marrow transplant recipients who had received gender-mismatched transplants 5–20 months earlier showed that most CEC in fresh blood had recipient genotype. Endothelial outgrowth from the same blood samples after 9 days in culture (5-fold expansion) was still predominantly of the recipient genotype. In contrast, endothelial outgrowth after ∼1 month (102-fold expansion) was mostly of donor genotype. Thus, recipient-genotype endothelial cells expanded only ∼20-fold over this period, whereas donor-genotype endothelial cells expanded ∼1000-fold. These data suggest that most CEC in fresh blood originate from vessel walls and have limited growth capability. Conversely, the data indicate that outgrowth of endothelial cells from cultures of blood is mostly derived from transplantable marrow-derived cells. Because these cells have more delayed outgrowth but a greater proliferative rate, our data suggest that they are derived from circulating angioblasts. PMID:10619863

  2. Red blood cell ghosts and intact red blood cells as complementary models in photodynamic cell research.

    PubMed

    Kaestner, Lars

    2004-05-01

    Recent research on erythrocytes as model cells for photodynamic therapy showed differing behaviour of certain photosensitisers in erythrocytes compared to other cells. Differences of dye accumulation in the cell membrane were proposed to be the reason for the distinct photodynamic effects. Using pheophorbide a as an example, the combination of erythrocyte ghosts as models to follow the dye accumulation in the cell membrane and intact erythrocytes as model cells to show the photodynamic damage is provided. Evidence for the correctness of the combination of erythrocyte ghosts and intact erythrocytes as a functioning model system in photodynamic cell research is provided using the confocal laser scanning microscopy on intact, pheophorbide a loaded erythrocytes.

  3. Technetium-99m-labeled red blood cell imaging

    SciTech Connect

    Front, D.; Israel, O.; Groshar, D.; Weininger, J.

    1984-07-01

    Red blood cells labeled with 99mTc constitute a suitable intravascular agent for imaging of vascular abnormalities. Hemangiomas are characterized by low perfusion and a high blood pool. This ''perfusion blood-pool mismatch,'' not encountered in other lesions, may help in the specific diagnosis of this tumor. This is particularly so in cavernous hemangiomas of the liver where three-phase 99mTc-labeled red blood cell scintigraphy should precede liver biopsy. Red cell scintigraphy also is useful for establishing the vascular nature of hemangiomas of the head and neck and the skin and for diagnosis of venous occlusion. Heat-damaged red blood cells provide a specific spleen imaging agent. This should be used when patients with suspected splenic pathology have equivocal colloid scintigraphy.

  4. An assessment of the cord blood:maternal blood methylmercury ratio: implications for risk assessment.

    PubMed Central

    Stern, Alan H; Smith, Andrew E

    2003-01-01

    In the current U.S. Environmental Protection Agency reference dose (RfD) for methylmercury, the one-compartment pharmacokinetic model is used to convert fetal cord blood mercury (Hg) concentration to a maternal intake dose. This requires a ratio relating cord blood Hg concentration to maternal blood Hg concentration. No formal analysis of either the central tendency or variability of this ratio has been done. This variability contributes to the overall variability in the dose estimate. A ratio of 1.0 is implicitly used in the model, but an uncertainty factor adjustment is applied to the central tendency estimate of dose to address variability in that estimate. Thus, incorporation of the cord:maternal ratio and its variability into the estimate of intake dose could result in a significant change in the value of the RfD. We analyzed studies providing data on the cord:maternal blood Hg ratio and conducted a Monte Carlo-based meta-analysis of 10 studies meeting all inclusion criteria to generate a comprehensive estimate of the central tendency and variability of the ratio. This analysis results in a recommended central tendency estimate of 1.7, a coefficient of variation of 0.56, and a 95th percentile of 3.4. By analogy to the impact of the similar hair:blood Hg ratio on the overall variability in the dose estimate, incorporation of the cord:maternal ratio may support a 3-fold uncertainty factor adjustment to the central tendency estimate of dose to account for pharmacokinetic variability. Whether the information generated in this analysis is sufficient to warrant a revision to the RfD will depend on the outcome of a comprehensive reanalysis of the entire one-compartment model. We are currently engaged in such an analysis. PMID:12948885

  5. White blood cell count - series (image)

    MedlinePlus

    How the test is performed: Adult or child: Blood is drawn from a vein (venipuncture), usually from the inside of the elbow or the back of the hand. The puncture site is cleaned with antiseptic, and a tourniquet ( ...

  6. The plasma protein fibrinogen stabilizes clusters of red blood cells in microcapillary flows.

    PubMed

    Brust, M; Aouane, O; Thiébaud, M; Flormann, D; Verdier, C; Kaestner, L; Laschke, M W; Selmi, H; Benyoussef, A; Podgorski, T; Coupier, G; Misbah, C; Wagner, C

    2014-03-11

    The supply of oxygen and nutrients and the disposal of metabolic waste in the organs depend strongly on how blood, especially red blood cells, flow through the microvascular network. Macromolecular plasma proteins such as fibrinogen cause red blood cells to form large aggregates, called rouleaux, which are usually assumed to be disaggregated in the circulation due to the shear forces present in bulk flow. This leads to the assumption that rouleaux formation is only relevant in the venule network and in arterioles at low shear rates or stasis. Thanks to an excellent agreement between combined experimental and numerical approaches, we show that despite the large shear rates present in microcapillaries, the presence of either fibrinogen or the synthetic polymer dextran leads to an enhanced formation of robust clusters of red blood cells, even at haematocrits as low as 1%. Robust aggregates are shown to exist in microcapillaries even for fibrinogen concentrations within the healthy physiological range. These persistent aggregates should strongly affect cell distribution and blood perfusion in the microvasculature, with putative implications for blood disorders even within apparently asymptomatic subjects.

  7. The plasma protein fibrinogen stabilizes clusters of red blood cells in microcapillary flows

    PubMed Central

    Brust, M.; Aouane, O.; Thiébaud, M.; Flormann, D.; Verdier, C.; Kaestner, L.; Laschke, M. W.; Selmi, H.; Benyoussef, A.; Podgorski, T.; Coupier, G.; Misbah, C.; Wagner, C.

    2014-01-01

    The supply of oxygen and nutrients and the disposal of metabolic waste in the organs depend strongly on how blood, especially red blood cells, flow through the microvascular network. Macromolecular plasma proteins such as fibrinogen cause red blood cells to form large aggregates, called rouleaux, which are usually assumed to be disaggregated in the circulation due to the shear forces present in bulk flow. This leads to the assumption that rouleaux formation is only relevant in the venule network and in arterioles at low shear rates or stasis. Thanks to an excellent agreement between combined experimental and numerical approaches, we show that despite the large shear rates present in microcapillaries, the presence of either fibrinogen or the synthetic polymer dextran leads to an enhanced formation of robust clusters of red blood cells, even at haematocrits as low as 1%. Robust aggregates are shown to exist in microcapillaries even for fibrinogen concentrations within the healthy physiological range. These persistent aggregates should strongly affect cell distribution and blood perfusion in the microvasculature, with putative implications for blood disorders even within apparently asymptomatic subjects. PMID:24614613

  8. The plasma protein fibrinogen stabilizes clusters of red blood cells in microcapillary flows

    NASA Astrophysics Data System (ADS)

    Brust, M.; Aouane, O.; Thiébaud, M.; Flormann, D.; Verdier, C.; Kaestner, L.; Laschke, M. W.; Selmi, H.; Benyoussef, A.; Podgorski, T.; Coupier, G.; Misbah, C.; Wagner, C.

    2014-03-01

    The supply of oxygen and nutrients and the disposal of metabolic waste in the organs depend strongly on how blood, especially red blood cells, flow through the microvascular network. Macromolecular plasma proteins such as fibrinogen cause red blood cells to form large aggregates, called rouleaux, which are usually assumed to be disaggregated in the circulation due to the shear forces present in bulk flow. This leads to the assumption that rouleaux formation is only relevant in the venule network and in arterioles at low shear rates or stasis. Thanks to an excellent agreement between combined experimental and numerical approaches, we show that despite the large shear rates present in microcapillaries, the presence of either fibrinogen or the synthetic polymer dextran leads to an enhanced formation of robust clusters of red blood cells, even at haematocrits as low as 1%. Robust aggregates are shown to exist in microcapillaries even for fibrinogen concentrations within the healthy physiological range. These persistent aggregates should strongly affect cell distribution and blood perfusion in the microvasculature, with putative implications for blood disorders even within apparently asymptomatic subjects.

  9. Measurement of Retinal Blood Flow Using Fluorescently Labeled Red Blood Cells1,2,3

    PubMed Central

    Kornfield, Tess E.

    2015-01-01

    Abstract Blood flow is a useful indicator of the metabolic state of the retina. However, accurate measurement of retinal blood flow is difficult to achieve in practice. Most existing optical techniques used for measuring blood flow require complex assumptions and calculations. We describe here a simple and direct method for calculating absolute blood flow in vessels of all sizes in the rat retina. The method relies on ultrafast confocal line scans to track the passage of fluorescently labeled red blood cells (fRBCs). The accuracy of the blood flow measurements was verified by (1) comparing blood flow calculated independently using either flux or velocity combined with diameter measurements, (2) measuring total retinal blood flow in arterioles and venules, (3) measuring blood flow at vessel branch points, and (4) measuring changes in blood flow in response to hyperoxic and hypercapnic challenge. Confocal line scans oriented parallel and diagonal to vessels were used to compute fRBC velocity and to examine velocity profiles across the width of vessels. We demonstrate that these methods provide accurate measures of absolute blood flow and velocity in retinal vessels of all sizes. PMID:26082942

  10. HEMORHEOLOGICAL IMPLICATIONS OF PERFLUOROCARBON BASED OXYGEN CARRIER INTERACTION WITH COLLOID PLASMA EXPANDERS AND BLOOD

    PubMed Central

    Vásquez, Diana M.; Ortiz, Daniel; Alvarez, Oscar A.; Briceño, Juan C.; Cabrales, Pedro

    2013-01-01

    Perfluorocarbon (PFC) emulsion based oxygen carriers lack colloid osmotic pressure (COP) and must be administered with colloid-based plasma expanders (PEs). Although PFC emulsions have been widely studied, there is limited information about PFC emulsion interaction with PEs and blood. Their interaction forms aggregates due to electrostatic and rheological phenomena, and change blood rheology and blood flow. This study analyzes the effects of the interaction between PFC emulsions with blood in the presence of clinically-used PEs. The rheological behavior of the mixtures was analyzed in parallel with in vivo analysis of blood flow in microvessels using intravital microscopy when administered in a clinically relevant scenario. The interaction between the PFC emulsion and PE with blood produced PFC droplets and red blood cell (RBCs) aggregation, and increased blood viscosity. The PFC droplets formed aggregates when mixed with PEs containing electrolytes, and the aggregation increased with the electrolyte concentration. Mixtures of PFC with PEs that produced PFC aggregates also induced RCBs aggregation when mixed with blood, increasing blood viscosity at low shear rates. The more viscous suspension at low shear rates produced a blunted blood flow velocity profile in vivo relative to non-aggregating mixtures of PFC and PEs. For the PEs evaluated, albumin produced minimal to undetectable aggregation. PFC and PEs interaction with blood can affect sections of the microcirculation with low shear rate (e.g. arterioles, venules, and pulmonary circulation) because aggregates could cause capillary occlusion, decrease perfusion, pulmonary emboli, or focal ischemia. PMID:23606592

  11. Detection and Characterization of Carcinoma Cells in the Blood

    NASA Astrophysics Data System (ADS)

    Racila, Emilian; Euhus, David; Weiss, Arthur J.; Rao, Chandra; McConnell, John; Terstappen, Leon W. M. M.; Uhr, Jonathan W.

    1998-04-01

    A highly sensitive assay combining immunomagnetic enrichment with multiparameter flow cytometric and immunocytochemical analysis has been developed to detect, enumerate, and characterize carcinoma cells in the blood. The assay can detect one epithelial cell or less in 1 ml of blood. Peripheral blood (10-20 ml) from 30 patients with carcinoma of the breast, from 3 patients with prostate cancer, and from 13 controls was examined by flow cytometry for the presence of circulating epithelial cells defined as nucleic acid+, CD45-, and cytokeratin+. Highly significant differences in the number of circulating epithelial cells were found between normal controls and patients with cancer including 17 with organ-confined disease. To determine whether the circulating epithelial cells in the cancer patients were neoplastic cells, cytospin preparations were made after immunomagnetic enrichment and were analyzed. Epithelial cells from patients with breast cancer generally stained with mAbs against cytokeratin and 3 of 5 for mucin-1. In contrast, no cells that stained for these antigens were observed in the blood from normal controls. The morphology of the stained cells was consistent with that of neoplastic cells. Of 8 patients with breast cancer followed for 1-10 months, there was a good correlation between changes in the level of tumor cells in the blood with both treatment with chemotherapy and clinical status. The present assay may be helpful in early detection, in monitoring disease, and in prognostication.

  12. Endothelial cell-derived microparticles induce plasmacytoid dendritic cell maturation: potential implications in inflammatory diseases

    PubMed Central

    Angelot, Fanny; Seillès, Estelle; Biichlé, Sabeha; Berda, Yael; Gaugler, Béatrice; Plumas, Joel; Chaperot, Laurence; Dignat-George, Françoise; Tiberghien, Pierre; Saas, Philippe; Garnache-Ottou, Francine

    2009-01-01

    Background Increased circulating endothelial microparticles, resulting from vascular endothelium dysfunction, and plasmacytoid dendritic cell activation are both encountered in common inflammatory disorders. The aim of our study was to determine whether interactions between endothelial microparticles and plasmacytoid dendritic cells could contribute to such pathologies. Design and Methods Microparticles generated from endothelial cell lines, platelets or activated T cells were incubated with human plasmacytoid dendritic cells sorted from healthy donor blood or with monocyte-derived dendritic cells. Dendritic cell maturation was evaluated by flow cytometry, cytokine secretion as well as naive T-cell activation and polarization. Labeled microparticles were also used to study cellular interactions. Results Endothelial microparticles induced plasmacytoid dendritic cell maturation. In contrast, conventional dendritic cells were resistant to endothelial microparticle-induced maturation. In addition to upregulation of co-stimulatory molecules, endothelial microparticle-matured plasmacytoid dendritic cells secreted inflammatory cytokines (interleukins 6 and 8, but no interferon-α) and also induced allogeneic naive CD4+ T cells to proliferate and to produce type 1 cytokines such as interferon-γ and tumor necrosis factor-α. Endothelial microparticle endocytosis by plasmacytoid dendritic cells appeared to be required for plasmacytoid dendritic cell maturation. Importantly, the ability of endothelial microparticles to induce plasmacytoid dendritic cells to mature was specific as microparticles derived from activated T cells or platelets (the major source of circulating microparticules in healthy subjects) did not induce such plasmacytoid dendritic cell maturation. Conclusions Our data show that endothelial microparticles specifically induce plasmacytoid dendritic cell maturation and production of inflammatory cytokines. This novel activation pathway may be implicated in

  13. Red blood cell damage by shear stress for different blood types

    NASA Astrophysics Data System (ADS)

    Arwatz, Gilad; Bedkowski, Katherine; Smits, Alexander

    2011-11-01

    In surgical practice, blood damage caused by medical devices is often a limiting factor in the duration of an acute procedure or in chronic exposures such as hemodialysis. In order to establish guidelines for designing medical devices, a study was conducted to determine the relationship between shear stress and damage to red blood cells using a concentric Couette device. By measuring the hemolysis level for various shear stresses and exposure times, a non-dimensional relationship between shear stress and blood damage for different blood types was established. Funding provided by Princeton University's Project X.

  14. Blood-brain barrier pathology in Alzheimer's and Parkinson's disease: implications for drug therapy.

    PubMed

    Desai, Brinda S; Monahan, Angela J; Carvey, Paul M; Hendey, Bill

    2007-01-01

    The blood-brain barrier (BBB) is a tightly regulated barrier in the central nervous system. Though the BBB is thought to be intact during neurodegenerative diseases such as Alzheimer's (AD) and Parkinson's disease (PD), recent evidence argues otherwise. Dysfunction of the BBB may be involved in disease progression, eliciting of peripheral immune response, and, most importantly, altered drug efficacy. In this review, we will give a brief overview of the BBB, its components, and their functions. We will critically evaluate the current literature in AD and PD BBB pathology resulting from insult, neuroinflammation, and neurodegeneration. Specifically, we will discuss alterations in tight junction, transport and endothelial cell surface proteins, and vascular density changes, all of which result in altered permeability. Finally, we will discuss the implications of BBB dysfunction in current and future therapeutics. Developing a better appreciation of BBB dysfunction in AD and PD may not only provide novel strategies in treatment, but will prove an interesting milestone in understanding neurodegenerative disease etiology and progression.

  15. Quantification of Depletion-Induced Adhesion of Red Blood Cells

    NASA Astrophysics Data System (ADS)

    Steffen, P.; Verdier, C.; Wagner, C.

    2013-01-01

    Red blood cells (RBCs) are known to form aggregates in the form of rouleaux due to the presence of plasma proteins under physiological conditions. The formation of rouleaux can also be induced in vitro by the addition of macromolecules to the RBC suspension. Current data on the adhesion strength between red blood cells in their natural discocyte shapes mostly originate from indirect measurements such as flow chamber experiments, but data is lacking at the single cell level. Here, we present measurements on the dextran-induced aggregation of red blood cells using atomic force microscopy-based single cell force spectroscopy. The effects of dextran concentration and molecular weight on the interaction energy of adhering RBCs were determined. The results on adhesion energy are in excellent agreement with a model based on the depletion effect and previous experimental studies. Furthermore, our method allowed to determine the adhesion force, a quantity that is needed in theoretical investigations on blood flow.

  16. Quantification of depletion-induced adhesion of red blood cells.

    PubMed

    Steffen, P; Verdier, C; Wagner, C

    2013-01-04

    Red blood cells (RBCs) are known to form aggregates in the form of rouleaux due to the presence of plasma proteins under physiological conditions. The formation of rouleaux can also be induced in vitro by the addition of macromolecules to the RBC suspension. Current data on the adhesion strength between red blood cells in their natural discocyte shapes mostly originate from indirect measurements such as flow chamber experiments, but data is lacking at the single cell level. Here, we present measurements on the dextran-induced aggregation of red blood cells using atomic force microscopy-based single cell force spectroscopy. The effects of dextran concentration and molecular weight on the interaction energy of adhering RBCs were determined. The results on adhesion energy are in excellent agreement with a model based on the depletion effect and previous experimental studies. Furthermore, our method allowed to determine the adhesion force, a quantity that is needed in theoretical investigations on blood flow.

  17. Mitochondria single nucleotide variation across six blood cell types.

    PubMed

    Zhang, Pan; Samuels, David C; Wang, Jing; Zhao, Shilin; Shyr, Yu; Guo, Yan

    2016-05-01

    It has been shown that heteroplasmic mitochondrial DNA variants can be tissue specific. However, whether mitochondrial DNA variants are specific by blood cell types has not been investigated. Motivated by this question and using mitochondria sequences extracted from RNAseq data from six distinct blood cell types (neutrophil, monocyte, myeloid dendritic, natural killer, T and B), we thoroughly compared SNPs and heteroplasmies among these cell types. Each cell type from each subject was sequenced at four time points used as biological replicates. We found that mitochondria content is low in neutrophil compared to the other five blood cell types. Subsequent analysis on the other five blood cell types showed that at the SNP level, there was no discrepancy. At the heteroplasmy level, we observed good concordances among all blood cell types. However, the allele frequencies of the heteroplasmy differed between blood cell types for certain heteroplasmic sites. Furthermore, we identified five tri-allelic sites (1610, 2617, 8303, 12146, 13710) that are likely caused by RNA editing. Three out of these five sites are located at the ninth position of tRNA genes, and are likely resulting from post-transcriptional methylation. Copyright © 2016 Elsevier B.V. and Mitochondria Research Society. All rights reserved.

  18. High-Throughput Separation of White Blood Cells From Whole Blood Using Inertial Microfluidics.

    PubMed

    Zhang, Jun; Yuan, Dan; Sluyter, Ronald; Yan, Sheng; Zhao, Qianbin; Xia, Huanming; Tan, Say Hwa; Nguyen, Nam-Trung; Li, Weihua

    2017-08-29

    White blood cells (WBCs) constitute only about 0.1% of human blood cells, yet contain rich information about the immune status of the body; thus, separation of WBCs from the whole blood is an indispensable and critical sample preparation step in many scientific, clinical, and diagnostic applications. In this paper, we developed a continuous and high-throughput microfluidic WBC separation platform utilizing the differential inertial focusing of particles in serpentine microchannels. First, separation performance of the proposed method is characterized and evaluated using polystyrene beads in the serpentine channel. The purity of 10-μm polystyrene beads is increased from 0.1% to 80.3% after two cascaded processes, with an average enrichment ratio of 28 times. Next, we investigated focusing and separation properties of Jurkat cells spiked in the blood to mimic the presence of WBCs in whole blood. Finally, separation of WBCs from human whole blood was conducted and separation purity of WBCs was measured by the flow cytometry. The results show that the purity of WBCs can be increased to 48% after two consecutive processes, with an average enrichment ratio of ten times. Meanwhile, a parallelized inertial microfluidic device was designed to provide a high processing flow rate of 288 ml/h for the diluted (×1/20) whole blood. The proposed microfluidic device can potentially work as an upstream component for blood sample preparation and analysis in the integrated microfluidic systems.

  19. Red blood cell dynamics: from cell deformation to ATP release.

    PubMed

    Wan, Jiandi; Forsyth, Alison M; Stone, Howard A

    2011-10-01

    The mechanisms of red blood cell (RBC) deformation under both static and dynamic, i.e., flow, conditions have been studied extensively since the mid 1960s. Deformation-induced biochemical reactions and possible signaling in RBCs, however, were proposed only fifteen years ago. Therefore, the fundamental relationship between RBC deformation and cellular signaling dynamics i.e., mechanotransduction, remains incompletely understood. Quantitative understanding of the mechanotransductive pathways in RBCs requires integrative studies of physical models of RBC deformation and cellular biochemical reactions. In this article we review the physical models of RBC deformation, spanning from continuum membrane mechanics to cellular skeleton dynamics under both static and flow conditions, and elaborate the mechanistic links involved in deformation-induced ATP release.

  20. Human umbilical cord blood cells and diabetes mellitus: recent advances.

    PubMed

    Reddi, Alluru S; Kothari, Neil; Kuppasani, Kishore; Ende, Norman

    2015-01-01

    Stem cell therapy for patients with diabetes is an area of great interest to both scientists and clinicians. Human umbilical cord blood cells (HUCBCs) are being increasingly used as a source of stem cells for cell-based therapy for diabetes because these cells can differentiate into pancreatic islet β-cells. Administration of HUCBCs has been shown to lower blood glucose levels in diabetic animal models. The use of autologous HUCBC transfusion in type 1 diabetic children has not shown any benefit. However, "Stem Cell Educator" therapy has shown promise in long term lowering of blood glucose levels in both type 1 and type 2 diabetic patients. In this review, we will briefly discuss recent advances in HUCBC therapy in the treatment of diabetes and some of its complications.

  1. Reflectance confocal microscopy of red blood cells: simulation and experiment.

    PubMed

    Zeidan, Adel; Yelin, Dvir

    2015-11-01

    Measuring the morphology of red blood cells is important for clinical diagnosis, providing valuable indications on a patient's health. In this work, we have simulated the appearance of normal red blood cells under a reflectance confocal microscope and discovered unique relations between the morphological parameters and the resulting characteristic interference patterns of the cell. The simulation results showed good agreement with in vitro reflectance confocal images of red blood cells, acquired using spectrally encoded flow cytometry that imaged the cells in a linear flow without artificial staining. By matching the simulated patterns to confocal images of the cells, this method could be used for measuring cell morphology in three dimensions and for studying their physiology.

  2. Photosensitized inactivation of infectious agents for sterilization of red blood cell concentrates and whole blood

    NASA Astrophysics Data System (ADS)

    Judy, Millard M.; Matthews, James Lester; Sogandares-Bernal, Franklin M.; Newman, Joseph T.; Chanh, Tran C.; Marengo-Rowe, Alain J.

    1992-06-01

    More than 10 million units of human blood components are transfused annually in the United States. Although donor screening and testing have greatly lowered the risk of transmission of viral and protozoan infectious agents, additional sterilization procedures which also preserve blood component function would be of significant value. Use of visible-light-range photosensitizers for sterilization of red blood cells is currently being aggressively investigated in laboratory-scale optical-mechanical systems. Both the photochemical sterilization process and the optical-mechanical system must operate without introducing significant alteration in the properties of the red cells. With successful demonstration of the efficacy and safety of these sterilization techniques, implementation in the blood bank setting will require scale-up to optical-mechanical systems capable of handling approximately 50,000 units daily in 500 - 1,000 blood banks in the United States.

  3. [Effects of infusion media on human red blood cell morphology].

    PubMed

    Burova, O O; Gusev, A A; Petrikov, S S; Gusev, S A; Basyreva, L Iu

    2006-01-01

    The effect of various infusion media on the structure of human red blood cells was evaluated in vitro and in vivo. The in vitro experiments used 10% sodium chloride (NaCl) solution, 10% glucose solution, 20% albumin solution, Rheopolyglucin, HyperHAES solution (18 g of NaCl in combination with 60 g of hydroxyethylstarch (HES), 200/0.5), Voluven (HES 130/0.4/9:1), and a combination of hypertensive NaCl solution and Rheopolyglucin. The morphofunctional response of red blood cells was studied in the clinical setting when 6% Voluven solution (HES 130/0.4/ 9:1) and hypertensive NaCl and glucose solutions were used. It was established that 10% NaCl solution caused considerable changes in the morphology of red blood cells both in the experiment and in patients with severe brain injury. The magnitude of structural changes increased as blood NaCl concentrations became higher. 10% glucose solution, Voluven, Rheopolyglucin, and albumin did not virtually affect the structure of red blood cells. Infusion of Voluven (500 ml of 6% solution for 40 minutes) induced no changes in the morphology of red blood cells in the clinical setting. Among the test solutions used to correct intracranial hypertension (HyperHAES, 10% NaCl, a combination of rheopolyglucin and 10% NaCl), HyperHAES exerted the least effect on the morphology of red blood cells.

  4. [Study on serological blood group conversion rule and clinical blood transfusion in allogeneic hematopoietic stem cell transplantation].

    PubMed

    Yu, Zhong-qing; Gao, Zhi-feng; Li, Hui-yu

    2012-08-01

    To explore the conversion rule of serological blood group and blood group substance after successful allogeneic hematopoietic stem cell transplantation, and to provide theory for clinical special blood type identification and blood transfusion. The growth cycle of recipient WBC and RBC, RBC chimera, blood group antibody production and remaining in full transition were observed. Conversion rule of blood group substance, contradiction between cells typing and sera typing were detected by saline medium tube method and microcolumn gel method after stem cells transplantation. The average time of engraftment in 21 recipients was about 18.6 days, RBC growth cycle in 8 major blood type incompatibility was 56.6 days, 25.9 days in 9 minor blood type incompatibility, 67 days in 4 bidirectional blood type incompatibility (P < 0.01). The ratio of RBC chimeric growth was 1:9, gradually converse to donor's blood group. Residue of recipient anti-A(B) was left after conditioning regimen, disappeared after full transformation, and recipient anti-A(B) was converse to donor's blood type in major blood type incompatibility. 5 A blood type recipient donated by O blood type blood generated anti-B instead of anti-A, 3 B blood type recipient generated only anti-A instead of B in minor blood type incompatibility, and 1 AB blood type recipient donated by A did not generate anti-B. Among 4 bidirectional blood type incompatibility, 2 B blood type recipient donated by A blood type blood did not generate anti-B, 2 A recipient by B could not produce anti-A. Recipient blood group substance helped original ABO blood type substance remain unchanged. Among patient with allogeneic hematopoietic stem cell transplantation, recipient's ABO and RBC blood type can be converse to donor's, but there is significant difference between patients of serological blood group and of normal people (P < 0.01). Recipient blood group substance helps original ABO blood type substance remain unchanged (P > 0.01).

  5. [Discovery of blood cells in the 17th century].

    PubMed

    Doubek, M

    2001-07-01

    Landmark works of the 17th century concerning observations of blood cells are quoted in the article. "Simple" and successively "compound" microscopes made their appearance in the late 16th century and early 17th century. In 1656, Frenchman Pierre Borel, physician-in-ordinary to the King Louis XIV, who first applied the microscope to medicine described a type of "worn" found in human blood. In 1657, Athanasius Kircher, a Jesuit priest and scientist from Germany, examined blood from plague victims, and described "worms" of plague. In 1661, 1664 and 1665, the blood cells were discerned by Marcello Malpighi. In 1678, the red blood corpuscles was described by Jan Swammerdam of Amsterdam, a Dutch naturalist and physician. The first complete account of the red cells was made by Anthony van Leeuwenhoek of Delft in the last quarter of the 17th century.

  6. Method for determining properties of red blood cells

    SciTech Connect

    Gourley, Paul L.

    2001-01-01

    A method for quantifying the concentration of hemoglobin in a cell, and indicia of anemia, comprises determining the wavelength of the longitudinal mode of a liquid in a laser microcavity; determining the wavelength of the fundamental transverse mode of a red blood cell in the liquid in the laser microcavity; and determining if the cell is anemic from the difference between the wavelength of the longitudinal mode and the fundamental transverse mode. In addition to measuring hemoglobin, the invention includes a method using intracavity laser spectroscopy to measure the change in spectra as a function of time for measuring the influx of water into a red blood cell and the cell's subsequent rupture.

  7. Vascular smooth muscle progenitor cells: building and repairing blood vessels.

    PubMed

    Majesky, Mark W; Dong, Xiu Rong; Regan, Jenna N; Hoglund, Virginia J

    2011-02-04

    Molecular pathways that control the specification, migration, and number of available smooth muscle progenitor cells play key roles in determining blood vessel size and structure, capacity for tissue repair, and progression of age-related disorders. Defects in these pathways produce malformations of developing blood vessels, depletion of smooth muscle progenitor cell pools for vessel wall maintenance and repair, and aberrant activation of alternative differentiation pathways in vascular disease. A better understanding of the molecular mechanisms that uniquely specify and maintain vascular smooth muscle cell precursors is essential if we are to use advances in stem and progenitor cell biology and somatic cell reprogramming for applications directed to the vessel wall.

  8. Red Blood Cell Dysfunction Induced by High-Fat Diet

    PubMed Central

    Unruh, Dusten; Srinivasan, Ramprasad; Benson, Tyler; Haigh, Stephen; Coyle, Danielle; Batra, Neil; Keil, Ryan; Sturm, Robert; Blanco, Victor; Palascak, Mary; Franco, Robert S.; Tong, Wilson; Chatterjee, Tapan; Hui, David Y.; Davidson, W. Sean; Aronow, Bruce J.; Kalfa, Theodosia; Manka, David; Peairs, Abigail; Blomkalns, Andra; Fulton, David J.; Brittain, Julia E.; Weintraub, Neal L.; Bogdanov, Vladimir Y.

    2015-01-01

    Background High-fat diet (HFD) promotes endothelial dysfunction and proinflammatory monocyte activation, which contribute to atherosclerosis in obesity. We investigated whether HFD also induces the dysfunction of red blood cells (RBCs), which serve as a reservoir for chemokines via binding to Duffy antigen receptor for chemokines (DARC). Methods and Results A 60% HFD for 12 weeks, which produced only minor changes in lipid profile in C57/BL6 mice, markedly augmented the levels of monocyte chemoattractant protein-1 bound to RBCs, which in turn stimulated macrophage migration through an endothelial monolayer. Levels of RBC-bound KC were also increased by HFD. These effects of HFD were abolished in DARC−/− mice. In RBCs from HFD-fed wild-type and DARC−/− mice, levels of membrane cholesterol and phosphatidylserine externalization were increased, fostering RBC-macrophage inflammatory interactions and promoting macrophage phagocytosis in vitro. When labeled ex vivo and injected into wild-type mice, RBCs from HFD-fed mice exhibited ≈3-fold increase in splenic uptake. Finally, RBCs from HFD-fed mice induced increased macrophage adhesion to the endothelium when they were incubated with isolated aortic segments, indicating endothelial activation. Conclusions RBC dysfunction, analogous to endothelial dysfunction, occurs early during diet-induced obesity and may serve as a mediator of atherosclerosis. These findings may have implications for the pathogenesis of atherosclerosis in obesity, a worldwide epidemic. PMID:26467254

  9. Vesicle-associated microRNAs are released from blood cells on incubation of blood samples.

    PubMed

    Köberle, Verena; Kakoschky, Bianca; Ibrahim, Ahmed Atef; Schmithals, Christian; Peveling-Oberhag, Jan; Zeuzem, Stefan; Kronenberger, Bernd; Waidmann, Oliver; Pleli, Thomas; Piiper, Albrecht

    2016-03-01

    MicroRNAs (miRNAs) circulating extracellularly in the blood are currently intensively studied as novel disease markers. However, the preanalytical factors influencing the levels of the extracellular miRNAs are still incompletely explored. In particular, it is unknown, whether the incubation of blood samples as occurring in clinical routine can lead to a release of miRNAs from blood cells and thus alter the extracellular miRNA levels before the preparation of serum or plasma from the blood cells. Using a set of marker miRNAs and quantitative RT-PCR, we found that the levels of extracellular miRNA-1, miRNA-16, and miRNA-21 were increased in EDTA and serum collection tubes incubated for 1-3 hours at room temperature and declined thereafter; the levels of the liver-specific miRNA-122 declined monophasically. These events occurred in the absence of significant hemolysis. When the blood was supplemented with Ribonuclease A inhibitor, the levels of miRNA-1, miRNA-16, and miRNA-21 increased substantially during the initial 3 hours of incubation and those of miRNA-122 remained unchanged, indicating that the release of blood cell-derived miRNAs occurred during the initial 3 hours of incubation of the blood tubes, but not at later time points. Separation of 5-hour preincubated blood into vesicle and nonvesicle fractions revealed a selective increase in the portion of vesicle-associated miRNAs. Together, these data indicate that the release of vesicle-associated miRNAs from blood cells can occur in blood samples within the time elapsing in normal clinical practice until their processing without significant hemolysis. This becomes particularly visible on the inhibition of miRNA degradation by Ribonuclease A inhibitor.

  10. Simultaneous measurement of red blood cell aggregation and whole blood coagulation using high-frequency ultrasound.

    PubMed

    Nam, Kweon-Ho; Yeom, Eunseop; Ha, Hojin; Lee, Sang Joon

    2012-03-01

    This study aims to investigate the feasibility of using high-frequency ultrasound (HFUS) for simultaneous monitoring of blood coagulation and red blood cell (RBC) aggregation. Using a 35-MHz ultrasound scanner, ultrasound speckle data were acquired from whole blood samples of three experimental groups of rats, including 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS)-treated, noncoagulation and normal control groups. The variations of blood echogenicity, the shape parameters of probability distribution of speckle intensity (skewness and kurtosis) and the correlation coefficient between two consecutive speckle data were calculated as a function of time starting from immediately after taking blood. The blood echogenicity increases rapidly to plateaus at the early stage of measurement for all the experimental groups caused by the formation of RBC aggregates. The DIDS-treated group exhibits the lowest echogenicity level due to the inhibitory effect of DIDS on RBC aggregation. The correlation analysis between consecutive speckle patterns seems to be useful to examine the variation of blood fluidity and the progress of clot formation. Whole blood coagulation is observed to be accelerated by DIDS treatment. In addition, the results of skewness and kurtosis analysis indicated that RBC aggregates may be disrupted during blood coagulation. The present study suggests that HFUS has good potential for simultaneous monitoring of RBC aggregation and blood coagulation to examine the relationship between them. Copyright © 2012 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  11. Quantification of red blood cell deformation at high-hematocrit blood flow in microvessels.

    PubMed

    Alizadehrad, Davod; Imai, Yohsuke; Nakaaki, Keita; Ishikawa, Takuji; Yamaguchi, Takami

    2012-10-11

    The deformation of red blood cells in microvessels was investigated numerically for various vessel diameters, hematocrits, and shear rates. We simulated blood flow in circular channels with diameters ranging from 9 to 50 μm, hematocrits from 20% to 45%, and shear rates from 20 to 150 s(-1) using a particle-based model with parallel computing. The apparent viscosity predicted by the simulation was in good agreement with previous experimental results. We quantified the deformation of red blood cells as a function of radial position. The numerical results demonstrated that because of the shape transition in response to local shear stress and the wall effect, the radial variation of red blood cell deformation in relatively large microvessels could be classified into three different regions: near-center, middle, and near-wall regions. Effects of the local shear stress and wall varied with vessel diameter, hematocrit, and shear rate. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. 21 CFR 864.7100 - Red blood cell enzyme assay.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Red blood cell enzyme assay. 864.7100 Section 864.7100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Hematology Kits and Packages § 864.7100 Red blood...

  13. Histochemistry of blood and bone marrow cells in pangolins.

    PubMed

    Caxton-Martins, A E

    1977-04-01

    Blood and bone marrow cells of pangolins have been examined histochemically. Sudanophilia, PAS positivity and acid phosphatase and alkaline phosphatase reactivity were confined to cells of the granulocytic and monocytic series, while peroxidase reactivity was confined to cells of the erythroid series. In this latter respect the pangolin is unique among mammals so far studied.

  14. Umbilical cord cell banking--implications for the future.

    PubMed

    Gunning, Jennifer

    2005-09-01

    The first successful cord cell transplant to a sibling with Fanconi's anaemia took place 15 years ago. This proven utility of cord blood led to the establishment of cord blood banks both private and public and there are now nearly 100 cord blood banks worldwide. It is estimated that over 200,000 cord blood units (CBU) are held by the private sector and over 160,000 CBU are registered with the largest public cord blood registry. There is a tension between private cord blood banks, which store CBU for autologous or family use, and public banks, which store CBU for unrelated use and the ethics of private cord blood storage has been questioned. But more general ethical questions also arise regarding ownership, consent, confidentiality, costs and quality standards and patenting. In looking at these ethical issues one also needs to look at potential future use of cord blood stem cells. Up until now cord cells have principally been used in the treatment of paediatric blood and immune disorders. Improvements in cell expansion technology will make CBU more appropriate also for treating adults with such disorders. However, it has also been demonstrated that cord blood stem cells have the capacity to differentiate into other types of cells, neuronal, bone, epithelial and muscle which would have a future role to play in cell therapy and regenerative medicine.

  15. Umbilical cord cell banking-implications for the future

    SciTech Connect

    Gunning, Jennifer . E-mail: gunning@cf.ac.uk

    2005-09-01

    The first successful cord cell transplant to a sibling with Fanconi's anaemia took place 15 years ago. This proven utility of cord blood led to the establishment of cord blood banks both private and public and there are now nearly 100 cord blood banks worldwide. It is estimated that over 200,000 cord blood units (CBU) are held by the private sector and over 160,000 CBU are registered with the largest public cord blood registry. There is a tension between private cord blood banks, which store CBU for autologous or family use, and public banks, which store CBU for unrelated use and the ethics of private cord blood storage has been questioned. But more general ethical questions also arise regarding ownership, consent, confidentiality, costs and quality standards and patenting. In looking at these ethical issues one also needs to look at potential future use of cord blood stem cells. Up until now cord cells have principally been used in the treatment of paediatric blood and immune disorders. Improvements in cell expansion technology will make CBU more appropriate also for treating adults with such disorders. However, it has also been demonstrated that cord blood stem cells have the capacity to differentiate into other types of cells, neuronal, bone, epithelial and muscle which would have a future role to play in cell therapy and regenerative medicine.

  16. Color contrast of red blood cells on solid substrate

    NASA Astrophysics Data System (ADS)

    Paiziev, Adkham A.

    2013-02-01

    In present study we developed the new method of colour visualization of red blood cells without using any chemical staining. The method based on physical phenomena a white light interference on thin transparent films. It is shown that in the case of thin human blood smears colour interference contrast occurs on solid polished substrates. The best contrast shows substrates with maximal refractive index (Mo, W, Si). These materials have been selected as substrate instead of ordinary microscopic slide in reflected light microscopy. It is shown that reflection of incident white light from blood cell surface and boundary cell-substrate generate two coherent lights. The second one (object signal) after passing through red blood cell gathers additional phase and after interference interaction with reference signal (light reflected from outer cell surface) enables cell image in colour. Number of blood smears of healthy persons (control) and patients who were diagnosed with cancer are presented. It is concluded that the offered method may be used as an effective diagnostic tool to detect early stage blood cells lesion by its interference painting in white light. Offered method may be used in research laboratories, hospitals, diagnostic centres, emergency medicine and other as complementary diagnostic tool to present convenient optical and electron microscopy technique.

  17. Image classification of unlabeled malaria parasites in red blood cells.

    PubMed

    Zheng Zhang; Ong, L L Sharon; Kong Fang; Matthew, Athul; Dauwels, Justin; Ming Dao; Asada, Harry

    2016-08-01

    This paper presents a method to detect unlabeled malaria parasites in red blood cells. The current "gold standard" for malaria diagnosis is microscopic examination of thick blood smear, a time consuming process requiring extensive training. Our goal is to develop an automate process to identify malaria infected red blood cells. Major issues in automated analysis of microscopy images of unstained blood smears include overlapping cells and oddly shaped cells. Our approach creates robust templates to detect infected and uninfected red cells. Histogram of Oriented Gradients (HOGs) features are extracted from templates and used to train a classifier offline. Next, the ViolaJones object detection framework is applied to detect infected and uninfected red cells and the image background. Results show our approach out-performs classification approaches with PCA features by 50% and cell detection algorithms applying Hough transforms by 24%. Majority of related work are designed to automatically detect stained parasites in blood smears where the cells are fixed. Although it is more challenging to design algorithms for unstained parasites, our methods will allow analysis of parasite progression in live cells under different drug treatments.

  18. How Cell Number and Cellular Properties of Blood-Banked Red Blood Cells of Different Cell Ages Decline during Storage

    PubMed Central

    Tuo, Wei-Wei; Wang, Di; Liang, Wen-Jing; Huang, Yao-Xiong

    2014-01-01

    Aims Numerous studies have suggested that transfusion of red blood cells (RBCs) stored over a long period of time may induce harmful effects due to storage-induced lesions. However, the underlying mechanisms responsible for this damage have not been identified. Furthermore, it is unclear why and how up to 30% of long-stored RBCs disappear from the circulation within 24 hours after transfusion. The aim of this study was to determine how the cell number of RBCs of different ages changes during storage and how these cells undergo cumulative structural and functional changes with storage time. Methods and Results We used Percoll centrifugation to fractionate the RBCs in blood bank stored RBC units into different aged sub-populations and then measured the number of intact cells in each sub-population as well the cells’ biomechanical and biochemical parameters as functions of the storage period. We found that the RBC units stored for ≤ 14 days could be separated into four fractions: the top or young cell fraction, two middle fractions, and the lower or old fraction. However, after 14 days of storage, the cell number and cellular properties declined rapidly whereby the units stored for 21 days only exhibited the three lower fractions and not the young fraction. The cell number within a unit stored for 21 days decreased by 23% compared to a fresh unit and the cells that were lost had hemolyzed into harmful membrane fragments, microparticles, and free hemoglobin. All remaining cells exhibited cellular properties similar to those of senescent cells. Conclusion In RBC units stored for greater than 14 days, there were fewer intact cells with no healthy cells present, as well as harmful membrane fragments, microparticles, and free hemoglobin. Therefore, transfusion of these stored units would not likely help patients and may induce a series of clinical problems. PMID:25167052

  19. Margination of White Blood Cells in Microcapillary Flow

    NASA Astrophysics Data System (ADS)

    Fedosov, Dmitry A.; Fornleitner, Julia; Gompper, Gerhard

    2012-01-01

    Margination of white blood cells (WBCs) towards vessel walls is an essential precondition for their efficient adhesion to the vascular endothelium. We perform numerical simulations with a two-dimensional blood flow model to investigate the dependence of WBC margination on hydrodynamic interactions of blood cells with the vessel walls, as well as on their collective behavior and deformability. We find WBC margination to be optimal in intermediate ranges of red blood cell (RBC) volume fractions and flow rates, while, beyond these ranges, it is substantially attenuated. RBC aggregation enhances WBC margination, while WBC deformability reduces it. These results are combined in state diagrams, which identify WBC margination for a wide range of flow and cell suspension conditions.

  20. Collection, Storage, and Preparation of Human Blood Cells

    PubMed Central

    Dagur, Pradeep K.; McCoy, J. Philip

    2015-01-01

    Human peripheral blood is often studied by flow cytometry in both the research and clinical laboratories. The methods for collection, storage, and preparation of peripheral blood will vary depending on the cell lineage to be examined as well as the type of assay to be performed. This unit presents protocols for collection of blood, separation of leukocytes from whole blood by lysis of erythrocytes, isolating mononuclear cells by density gradient separation, and assorted non-flow sorting methods, such as magnetic bead separations, for enriching specific cell populations, including monocytes, T lymphocytes, B lymphocytes, neutrophils,, , and platelets prior to flow cytometric analysis. A protocol is also offered for cryopreservation of cells since clinical research often involves retrospective flow cytometric analysis of samples stored over a period of months or years. PMID:26132177

  1. Novel Automated Blood Separations Validate Whole Cell Biomarkers

    PubMed Central

    Burger, Douglas E.; Wang, Limei; Ban, Liqin; Okubo, Yoshiaki; Kühtreiber, Willem M.; Leichliter, Ashley K.; Faustman, Denise L.

    2011-01-01

    Background Progress in clinical trials in infectious disease, autoimmunity, and cancer is stymied by a dearth of successful whole cell biomarkers for peripheral blood lymphocytes (PBLs). Successful biomarkers could help to track drug effects at early time points in clinical trials to prevent costly trial failures late in development. One major obstacle is the inaccuracy of Ficoll density centrifugation, the decades-old method of separating PBLs from the abundant red blood cells (RBCs) of fresh blood samples. Methods and Findings To replace the Ficoll method, we developed and studied a novel blood-based magnetic separation method. The magnetic method strikingly surpassed Ficoll in viability, purity and yield of PBLs. To reduce labor, we developed an automated platform and compared two magnet configurations for cell separations. These more accurate and labor-saving magnet configurations allowed the lymphocytes to be tested in bioassays for rare antigen-specific T cells. The automated method succeeded at identifying 79% of patients with the rare PBLs of interest as compared with Ficoll's uniform failure. We validated improved upfront blood processing and show accurate detection of rare antigen-specific lymphocytes. Conclusions Improving, automating and standardizing lymphocyte detections from whole blood may facilitate development of new cell-based biomarkers for human diseases. Improved upfront blood processes may lead to broad improvements in monitoring early trial outcome measurements in human clinical trials. PMID:21799852

  2. Freeze-Dried Human Red Blood Cells

    DTIC Science & Technology

    1991-11-08

    which we thought may improve the resealing and phospholipid packing of the cell membranes. Neither treatment appeared to significantly improve the cell...cells were experiencing subtle membrane damage. This hypothesis was based on our model of transient lysis- resealing of the cells during the shock of...appreciable rates of chemical reactions. This theory has already found general application in the food and pharmaceuticals (i.e., lyophilized protein

  3. Red blood cell and iron metabolism during space flight

    NASA Technical Reports Server (NTRS)

    Smith, Scott M.

    2002-01-01

    Space flight anemia is a widely recognized phenomenon in astronauts. Reduction in circulating red blood cells and plasma volume results in a 10% to 15% decrement in circulatory volume. This effect appears to be a normal physiologic adaptation to weightlessness and results from the removal of newly released blood cells from the circulation. Iron availability increases, and (in the few subjects studied) iron stores increase during long-duration space flight. The consequences of these changes are not fully understood.

  4. Red blood cell and iron metabolism during space flight

    NASA Technical Reports Server (NTRS)

    Smith, Scott M.

    2002-01-01

    Space flight anemia is a widely recognized phenomenon in astronauts. Reduction in circulating red blood cells and plasma volume results in a 10% to 15% decrement in circulatory volume. This effect appears to be a normal physiologic adaptation to weightlessness and results from the removal of newly released blood cells from the circulation. Iron availability increases, and (in the few subjects studied) iron stores increase during long-duration space flight. The consequences of these changes are not fully understood.

  5. Drawings of Blood Cells Reveal People’s Perception of Their Blood Disorder: A Pilot Study

    PubMed Central

    Ramondt, Steven; Cameron, Linda D.; Broadbent, Elizabeth; Kaptein, Adrian A.

    2016-01-01

    Context Sickle cell disease (SCD) and thalassemia are rare but chronic blood disorders. Recent literature showed impaired quality of life (QOL) in people with these blood disorders. Assessing one of the determinants of QOL (i.e. illness perceptions) therefore, is an important next research area. Objective We aimed to explore illness perceptions of people with a blood disorder with drawings in addition to the Brief Illness Perception Questionnaire (Brief IPQ). Drawings are a novel method to assess illness perceptions and the free-range answers drawings offer can add additional insight into how people perceive their illness. Method We conducted a cross-sectional study including 17 participants with a blood disorder. Participants’ illness perceptions were assessed by the Brief IPQ and drawings. Brief IPQ scores were compared with reference groups from the literature (i.e. people with asthma or lupus erythematosus). Results Participants with SCD or thalassemia perceived their blood disorder as being more chronic and reported more severe symptoms than people with either asthma or lupus erythematosus. In the drawings of these participants with a blood disorder, a greater number of blood cells drawn was negatively correlated with perceived personal control (P<0.05), indicating that a greater quantity in the drawing is associated with more negative or distressing beliefs. Conclusion Participants with a blood disorder perceive their disease as fairly threatening compared with people with other chronic illnesses. Drawings can add additional insight into how people perceive their illness by offering free-range answers. PMID:27123580

  6. Red blood cell transport mechanisms in polyester thread-based blood typing devices.

    PubMed

    Nilghaz, Azadeh; Ballerini, David R; Guan, Liyun; Li, Lizi; Shen, Wei

    2016-02-01

    A recently developed blood typing diagnostic based on a polyester thread substrate has shown great promise for use in medical emergencies and in impoverished regions. The device is easy to use and transport, while also being inexpensive, accurate, and rapid. This study used a fluorescent confocal microscope to delve deeper into how red blood cells were behaving within the polyester thread-based diagnostic at the cellular level, and how plasma separation could be made to visibly occur on the thread, making it possible to identify blood type in a single step. Red blood cells were stained and the plasma phase dyed with fluorescent compounds to enable them to be visualised under the confocal microscope at high magnification. The mechanisms uncovered were in surprising contrast with those found for a similar, paper-based method. Red blood cell aggregates did not flow over each other within the thread substrate as expected, but suffered from a restriction to their flow which resulted in the chromatographic separation of the RBCs from the liquid phase of the blood. It is hoped that these results will lead to the optimisation of the method to enable more accurate and sensitive detection, increasing the range of blood systems that can be detected.

  7. Non-invasive spectroscopy of transfusable red blood cells stored inside sealed plastic blood-bags.

    PubMed

    Buckley, K; Atkins, C G; Chen, D; Schulze, H G; Devine, D V; Blades, M W; Turner, R F B

    2016-03-07

    After being separated from (donated) whole blood, red blood cells are suspended in specially formulated additive solutions and stored (at 4 °C) in polyvinyl chloride (PVC) blood-bags until they are needed for transfusion. With time, the prepared red cell concentrate (RCC) is known to undergo biochemical changes that lower effectiveness of the transfusion, and thus regulations are in place that limit the storage period to 42 days. At present, RCC is not subjected to analytical testing prior to transfusion. In this study, we use Spatially Offset Raman Spectroscopy (SORS) to probe, non-invasively, the biochemistry of RCC inside sealed blood-bags. The retrieved spectra compare well with conventional Raman spectra (of sampled aliquots) and are dominated by features associated with hemoglobin. In addition to the analytical demonstration that SORS can be used to retrieve RCC spectra from standard clinical blood-bags without breaking the sterility of the system, the data reveal interesting detail about the oxygenation-state of the stored cells themselves, namely that some blood-bags unexpectedly contain measurable amounts of deoxygenated hemoglobin after weeks of storage. The demonstration that chemical information can be obtained non-invasively using spectroscopy will enable new studies of RCC degeneration, and points the way to a Raman-based instrument for quality-control in a blood-bank or hospital setting.

  8. Effective and selective cell retention and recovery from whole blood by electroactive thin films.

    PubMed

    Xiao, Yun; Zhou, Hangyu; Xuan, Nanxia; Cheng, Meng; Rao, Yuefeng; Luo, Yan; Wang, Ben; Tang, Ruikang

    2014-12-10

    Hematogenous metastatic spread causes most cancer patient deaths. Because circulating tumor cells (CTCs) are highly relevant to early metastatic spread, the capture or detection of these cells provides a diagnostic tool for patients with metastatic conditions. Herein, we demonstrate a programmable electroactive multilayered material platform with a smart electrically induced "switch" that captures CTCs from biological plasma with high efficiency and releases the captured cells flexibly. The released cells are still viable and proliferative, which facilitates the detection of trace levels of CTCs by amplification. Furthermore, the inherent rough characteristics of the nanoparticle-composed interface can promote capture efficiency and cell purification by integration with a simple microfluidic device. This elegant, inexpensive, and versatile platform for cell sorting and enrichment makes subsequent molecular and cell biological analysis achievable. The strategy has broad implications for favoring fundamental cancer biology research, for the diagnosis and monitoring of cancer individually, and for advanced intervention based on blood purification.

  9. Chronic red blood cell exchange to prevent clinical complications in sickle cell disease.

    PubMed

    Cabibbo, Sergio; Fidone, Carmelo; Garozzo, Giovanni; Antolino, Agostino; Manenti, Giovanna Oriella; Bennardello, Francesco; Licitra, Vincenzo; Calabrese, Salvatore; Costantino, Francesco; Travali, Simone; Distefano, Roberto; Bonomo, Pietro

    2005-06-01

    We tracked the results of 394 manual or automatic red blood cell exchanges done with a cell separator in 20 sickle cell patients at high risk for recurrent complications. Over an average of 6 years, none of the patients developed complications related to the procedure or to the increased blood use. It was safe and effective in preventing complications of sickle cell disease, and if done automatically, reduced iron overload. Ferritin levels also decreased in patients treated with automatic red blood cell exchange. Furthermore, using Single Donor Red Blood Cell units (SDRC) we reduced the potential exposure to transfusion transmitted infectious diseases (TTI).

  10. Healthy and unhealthy red blood cell detection in human blood smears using neural networks.

    PubMed

    Elsalamony, Hany A

    2016-04-01

    One of the most common diseases that affect human red blood cells (RBCs) is anaemia. To diagnose anaemia, the following methods are typically employed: an identification process that is based on measuring the level of haemoglobin and the classification of RBCs based on a microscopic examination in blood smears. This paper presents a proposed algorithm for detecting and counting three types of anaemia-infected red blood cells in a microscopic coloured image using circular Hough transform and morphological tools. Anaemia cells include sickle, elliptocytosis, microsite cells and cells with unknown shapes. Additionally, the resulting data from the detection process have been analysed by a prevalent data analysis technique: the neural network. The experimental results for this model have demonstrated high accuracy for analysing healthy/unhealthy cells. This algorithm has achieved a maximum detection of approximately 97.8% of all cells in 21 microscopic images. Effectiveness rates of 100%, 98%, 100%, and 99.3% have been achieved using neural networks for sickle cells, elliptocytosis cells, microsite cells and cells with unknown shapes, respectively. Copyright © 2016. Published by Elsevier Ltd.

  11. Insights and hopes in umbilical cord blood stem cell transplantations.

    PubMed

    Shahrokhi, Somayeh; Menaa, Farid; Alimoghaddam, Kamran; McGuckin, Colin; Ebtekar, Massoumeh

    2012-01-01

    Over 20.000 umblical cord blood transplantations (UCBT) have been carried out around the world. Indeed, UCBT represents an attractive source of donor hematopoietic stem cells (HSCs) and, offer interesting features (e.g., lower graft-versus-host disease) compared to bone marrow transplantation (BMT). Thereby, UCBT often represents the unique curative option against several blood diseases. Recent advances in the field of UCBT, consisted to develop strategies to expand umbilical stem cells and shorter the timing of their engraftment, subsequently enhancing their availability for enhanced efficacy of transplantation into indicated patients with malignant diseases (e.g., leukemia) or non-malignant diseases (e.g., thalassemia major). Several studies showed that the expansion and homing of UCBSCs depends on specific biological factors and cell types (e.g., cytokines, neuropeptides, co-culture with stromal cells). In this review, we extensively present the advantages and disadvantages of current hematopoietic stem cell transplantations (HSCTs), compared to UBCT. We further describe the importance of cord blood content and obstetric factors on cord blood selection, and report the recent approaches that can be undertook to improve cord blood stem cell expansion as well as engraftment. Eventually, we provide two majors examples underlining the importance of UCBT as a potential cure for blood diseases.

  12. Insights and Hopes in Umbilical Cord Blood Stem Cell Transplantations

    PubMed Central

    Shahrokhi, Somayeh; Menaa, Farid; Alimoghaddam, Kamran; McGuckin, Colin; Ebtekar, Massoumeh

    2012-01-01

    Over 20.000 umblical cord blood transplantations (UCBT) have been carried out around the world. Indeed, UCBT represents an attractive source of donor hematopoietic stem cells (HSCs) and, offer interesting features (e.g., lower graft-versus-host disease) compared to bone marrow transplantation (BMT). Thereby, UCBT often represents the unique curative option against several blood diseases. Recent advances in the field of UCBT, consisted to develop strategies to expand umbilical stem cells and shorter the timing of their engraftment, subsequently enhancing their availability for enhanced efficacy of transplantation into indicated patients with malignant diseases (e.g., leukemia) or non-malignant diseases (e.g., thalassemia major). Several studies showed that the expansion and homing of UCBSCs depends on specific biological factors and cell types (e.g., cytokines, neuropeptides, co-culture with stromal cells). In this review, we extensively present the advantages and disadvantages of current hematopoietic stem cell transplantations (HSCTs), compared to UBCT. We further describe the importance of cord blood content and obstetric factors on cord blood selection, and report the recent approaches that can be undertook to improve cord blood stem cell expansion as well as engraftment. Eventually, we provide two majors examples underlining the importance of UCBT as a potential cure for blood diseases. PMID:23258957

  13. Alpha thalassemia protects sickle cell anemia patients from macro-albuminuria through its effects on red blood cell rheological properties.

    PubMed

    Lamarre, Yann; Romana, Marc; Lemonne, Nathalie; Hardy-Dessources, Marie-Dominique; Tarer, Vanessa; Mougenel, Danielle; Waltz, Xavier; Tressières, Benoît; Lalanne-Mistrih, Marie-Laure; Etienne-Julan, Maryse; Connes, Philippe

    2014-01-01

    While chronic hemolysis has been suspected to be involved in the development of glomerulopathy in patients with sickle cell anemia (SCA), no study focused on the implications of blood rheology. Ninety-six adults with SCA at steady state were included in the present cross-sectional study. Three categories were defined: normo-albuminuria (NORMO, n = 41), micro-albuminuria (MICRO, n = 23) and macro-albuminuria (MACRO, n = 32). Blood was sampled to measure hematological and hemorheological parameters, and genomic DNA extraction was performed to detect the presence of α-thalassemia. The prevalence of α-thalassemia was lower in the MACRO group compared with the two other groups. Anemia was more severe in the MACRO compared with the NORMO group leading the former group to exhibit decreased blood viscosity. Red blood cell deformability was lower and red blood cell aggregates strength was greater in the MACRO compared to the two other groups, and this was directly attributed to the lower frequency of α-thalassemia in the former group. Our results show the protective role of α-thalassemia against the development of sickle cell glomerulopathy, and strongly suggest that this protection is mediated through the decrease of anemia, the increase of RBC deformability and the lowering of the RBC aggregates strength.

  14. A microfluidic device for continuous white blood cell separation and lysis from whole blood.

    PubMed

    Kim, Myounggon; Mo Jung, Seung; Lee, Kyeong-Hwan; Jun Kang, Yang; Yang, Sung

    2010-11-01

    A microfluidic device, which is composed of a blood inlet, a cell lysis solution inlet, a bifurcation outlet containing six microchannels, and a white blood cell (WBC)-lysed solution outlet, is proposed in this study to separate WBCs from whole blood and lyse the WBCs in a continuous and near real-time fashion. The geometry of the microfluidic device is determined based on the bifurcation law and a cell crossover method. The microflow patterns of blood cells in the microfluidic channels are simulated by computational fluid dynamics. The simulation results agree with the experiment results by considering the reduction of blood viscosity in the microfluidic channels. The performance of the microfluidic device is evaluated by investigating the WBC recovery efficiency and the ratio of spectrophotometric absorbance of the blood sample at 260 to that at 280nm. The WBC recovery efficiency at the main channel outlet is 97.2%. The measured spectrophotometric absorbance ratio of 1.82 indicates that the separated WBCs are completely lysed, leaving only pure DNA in the WBC-lysed solution. The continuous cell separation and lysis is completed within only 0.5s. Therefore, it is concluded that the proposed microfluidic device is promising for separating WBCs from whole blood without any pretreatment and lysing the WBCs in a continuous and near real-time fashion. The proposed microfluidic device may be applicable to a lab-on-a-chip for blood analysis. © 2010, Copyright the Authors. Artificial Organs © 2010, International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  15. Blood flow simulation on a role for red blood cells in platelet adhesion

    NASA Astrophysics Data System (ADS)

    Shimizu, Kazuya; Sugiyama, Kazuyasu; Takagi, Shu

    2016-11-01

    Large-scale blood flow simulations were conducted and a role for red blood cells in platelet adhesion was discussed. The flow conditions and hematocrit values were set to the same as corresponding experiments, and the numerical results were compared with the measurements. Numerical results show the number of platelets adhered on the wall is increased with the increase in hematocrit values. The number of adhered platelets estimated from the simulation was approximately 28 (per 0.01 square millimeter per minute) for the hematocrit value of 20%. These results agree well with the experimental results qualitatively and quantitatively, which proves the validity of the present numerical model including the interaction between fluid and many elastic bodies and the modeling of platelet adhesion. Numerical simulation also reproduces the behavior of red blood cells in the blood flow and their role in platelet adhesion. Red blood cells deform to a flat shape and move towards channel center region. In contrast, platelets are pushed out and have many chances to contact with the wall. As a result, the large number of adhered platelets is observed as hematocrit values becomes high. This result indicates the presence of red blood cells plays a crucial role in platelet adhesion.

  16. DNA methylation of cord blood cell types: Applications for mixed cell birth studies.

    PubMed

    Bakulski, Kelly M; Feinberg, Jason I; Andrews, Shan V; Yang, Jack; Brown, Shannon; L McKenney, Stephanie; Witter, Frank; Walston, Jeremy; Feinberg, Andrew P; Fallin, M Daniele

    2016-05-03

    Epigenome-wide association studies of disease widely use DNA methylation measured in blood as a surrogate tissue. Cell proportions can vary between people and confound associations of exposure or outcome. An adequate reference panel for estimating cell proportions from adult whole blood for DNA methylation studies is available, but an analogous cord blood cell reference panel is not yet available. Cord blood has unique cell types and the epigenetic signatures of standard cell types may not be consistent throughout the life course. Using magnetic bead sorting, we isolated cord blood cell types (nucleated red blood cells, granulocytes, monocytes, natural killer cells, B cells, CD4(+)T cells, and CD8(+)T cells) from 17 live births at Johns Hopkins Hospital. We confirmed enrichment of the cell types using fluorescence assisted cell sorting and ran DNA from the separated cell types on the Illumina Infinium HumanMethylation450 BeadChip array. After filtering, the final analysis was on 104 samples at 429,794 probes. We compared cell type specific signatures in cord to each other and methylation at 49.2% of CpG sites on the array differed by cell type (F-test P < 10(-8)). Differences between nucleated red blood cells and the remainder of the cell types were most pronounced (36.9% of CpG sites at P < 10(-8)) and 99.5% of these sites were hypomethylated relative to the other cell types. We also compared the mean-centered sorted cord profiles to the available adult reference panel and observed high correlation between the overlapping cell types for granulocytes and monocytes (both r=0.74), and poor correlation for CD8(+)T cells and NK cells (both r=0.08). We further provide an algorithm for estimating cell proportions in cord blood using the newly developed cord reference panel, which estimates biologically plausible cell proportions in whole cord blood samples.

  17. DNA methylation of cord blood cell types: Applications for mixed cell birth studies

    PubMed Central

    Bakulski, Kelly M.; Feinberg, Jason I.; Andrews, Shan V.; Yang, Jack; Brown, Shannon; L. McKenney, Stephanie; Witter, Frank; Walston, Jeremy; Feinberg, Andrew P.; Fallin, M. Daniele

    2016-01-01

    ABSTRACT Epigenome-wide association studies of disease widely use DNA methylation measured in blood as a surrogate tissue. Cell proportions can vary between people and confound associations of exposure or outcome. An adequate reference panel for estimating cell proportions from adult whole blood for DNA methylation studies is available, but an analogous cord blood cell reference panel is not yet available. Cord blood has unique cell types and the epigenetic signatures of standard cell types may not be consistent throughout the life course. Using magnetic bead sorting, we isolated cord blood cell types (nucleated red blood cells, granulocytes, monocytes, natural killer cells, B cells, CD4+T cells, and CD8+T cells) from 17 live births at Johns Hopkins Hospital. We confirmed enrichment of the cell types using fluorescence assisted cell sorting and ran DNA from the separated cell types on the Illumina Infinium HumanMethylation450 BeadChip array. After filtering, the final analysis was on 104 samples at 429,794 probes. We compared cell type specific signatures in cord to each other and methylation at 49.2% of CpG sites on the array differed by cell type (F-test P < 10−8). Differences between nucleated red blood cells and the remainder of the cell types were most pronounced (36.9% of CpG sites at P < 10−8) and 99.5% of these sites were hypomethylated relative to the other cell types. We also compared the mean-centered sorted cord profiles to the available adult reference panel and observed high correlation between the overlapping cell types for granulocytes and monocytes (both r=0.74), and poor correlation for CD8+T cells and NK cells (both r=0.08). We further provide an algorithm for estimating cell proportions in cord blood using the newly developed cord reference panel, which estimates biologically plausible cell proportions in whole cord blood samples. PMID:27019159

  18. Raman spectroscopy of stored red blood cells: evaluating clinically-relevant biochemical markers in donated blood

    NASA Astrophysics Data System (ADS)

    Atkins, Chad G.; Buckley, Kevin; Chen, Deborah; Schulze, H. G.; Devine, Dana V.; Blades, Michael W.; Turner, Robin F. B.

    2015-07-01

    Modern transfusion medicine relies on the safe, secure, and cost-effective delivery of donated red blood cells (RBCs). Once isolated, RBCs are suspended in a defined additive solution and stored in plastic blood bags in which, over time, they undergo chemical, physiological, and morphological changes that may have a deleterious impact on some patients. Regulations limit the storage period to 42 days and the cells do not routinely undergo analytical testing before use. In this study, we use Raman spectroscopy to interrogate stored RBCs and we identify metabolic and cell-breakdown products, such as haemoglobin and membrane fragments, that build-up in the blood bags as the cells age. Our work points the way to the development of an instrument which could quickly and easily assess the biochemical nature of stored RBC units before they are transfused.

  19. Mapping viscoelastic properties of healthy and pathological red blood cells at the nanoscale level.

    PubMed

    Ciasca, G; Papi, M; Di Claudio, S; Chiarpotto, M; Palmieri, V; Maulucci, G; Nocca, G; Rossi, C; De Spirito, M

    2015-10-28

    In order to pass through the microcirculation, red blood cells (RBCs) need to undergo extensive deformations and to recover the original shape. This extreme deformability is altered by various pathological conditions. On the other hand, an altered RBC deformability can have major effects on blood flow and can lead to pathological implications. The study of the viscoelastic response of red blood cells to mechanical stimuli is crucial to fully understand deformability changes under pathological conditions. However, the typical erythrocyte biconcave shape hints to a complex and intrinsically heterogeneous mechanical response that must be investigated by using probes at the nanoscale level. In this work, the local viscoelastic behaviour of healthy and pathological red blood cells was probed by Atomic Force Microscopy (AFM). Our results clearly show that the RBC stiffness is not spatially homogeneous, suggesting a strong correlation with the erythrocyte biconcave shape. Moreover, our nanoscale mapping highlights the key role played by viscous forces, demonstrating that RBCs do not behave as pure elastic bodies. The fundamental role played by viscous forces is further strengthened by the comparison between healthy and pathological (diabetes mellitus) RBCs. It is well known that pathological RBCs are usually stiffer than the healthy ones. Our measures unveil a more complex scenario according to which the difference between normal and pathological red blood cells does not merely lie in their stiffness but also in a different dynamical response to external stimuli that is governed by viscous forces.

  20. On ultrasound-induced microbubble oscillation in a capillary blood vessel and its implications for the blood-brain barrier

    NASA Astrophysics Data System (ADS)

    Wiedemair, W.; Tuković, Ž.; Jasak, H.; Poulikakos, D.; Kurtcuoglu, V.

    2012-02-01

    The complex interaction between an ultrasound-driven microbubble and an enclosing capillary microvessel is investigated by means of a coupled, multi-domain numerical model using the finite volume formulation. This system is of interest in the study of transient blood-brain barrier disruption (BBBD) for drug delivery applications. The compliant vessel structure is incorporated explicitly as a distinct domain described by a dedicated physical model. Red blood cells (RBCs) are taken into account as elastic solids in the blood plasma. We report the temporal and spatial development of transmural pressure (Ptm) and wall shear stress (WSS) at the luminal endothelial interface, both of which are candidates for the yet unknown mediator of BBBD. The explicit introduction of RBCs shapes the Ptm and WSS distributions and their derivatives markedly. While the peak values of these mechanical wall parameters are not affected considerably by the presence of RBCs, a pronounced increase in their spatial gradients is observed compared to a configuration with blood plasma alone. The novelty of our work lies in the explicit treatment of the vessel wall, and in the modelling of blood as a composite fluid, which we show to be relevant for the mechanical processes at the endothelium.

  1. Induction and identification of rabbit peripheral blood derived dendritic cells

    NASA Astrophysics Data System (ADS)

    Zhou, Jing; Yang, FuYuan; Chen, WenLi

    2012-03-01

    Purpose: To study a method of the induction of dendritic cells (DCs) from rabbit peripheral blood. Methods: Peripheral blood cells were removed from rabbit, filtered through nylon mesh. Peripheral blood mononuclear cells (PBMC) were isolated from the blood cells by Ficoll-Hypaque centrifugation (density of 1.077g/cm3).To obtain DCs, PBMC were cultured in RPMI1640 medium containing 10% fetal calf serum, 50U/mL penicillin and streptomycin, referred to subsequently as complete medium, at 37°C in 5% CO2 atmosphere for 4 hours. Nonadherent cells were aspirated, adherent cells were continued incubated in complete medium, supplemented with granulocyte/macrophage colony-stimulating factor (GM-CSF, 50ng/ml),and interleukin 4 (IL-4, 50ng/ml) for 9 days. Fluorescein labeled antibodies(anti-CD14, anti-HLA-DR, anti-CD86) were used to sign cells cultured for 3,6,9 days respectively, Then flow cytometry was performed. Results: Ratio of anti-HLA-DR and anti-CD86 labeled cells increased with induction time extension, in contrast with anti-CD14. Conclusion: Dendritic cells can be effectively induced by the method of this experiment, cell maturation status increased with induction time extension.

  2. Perturbation of red blood cell membrane rigidity by extracellular ligands.

    PubMed

    Paulitschke, M; Nash, G B; Anstee, D J; Tanner, M J; Gratzer, W B

    1995-07-01

    It is known that binding of extracellular antibodies against the major sialoglycoprotein, glycophorin A, reduced the deformability of the red blood cell membrane. This has been taken to result from new or altered interactions between the glycophorin A and the membrane skeleton. We have shown by means of the micropipette aspiration technique that antibodies against the preponderant transmembrane protein, band 3, induce similar effects. A definite but much smaller reduction in elasticity of the membrane is engendered by univalent Fab fragments of the anti-band 3 antibodies. By examining cells genetically devoid of glycophorin A or containing a variant of this constituent, truncated at the inner membrane surface, we have shown that the anti-band 3 antibodies do not act through the band 3-associated glycophorin A. We examined the effect of anti-glycophorin A antibodies on homozygous Wr(a+b-) cells, in which an amino acid replacement in band 3 annihilates the Wright b (Wrb) epitope (comprising sequence elements of glycophorin A and band 3) and thus, by implication disrupts or perturbs the band 3-glycophorin A interaction; these cells show a much smaller response to an anti-glycophorin A antibody than do normal controls. We infer that in this case anti-glycophorin A antibodies exert their rigidifying effect through the associated band 3. Another anti-glycophorin A antibody, directed against an epitope remote from the membrane surface, however, increases the rigidity of both Wr(a+b-) and normal cells. This implies that not all antibodies act in the same manner in modifying the membrane mechanical properties. The effect exerted by anti-band 3 antibodies appears not to be transmitted through the band 3-ankyrin-spectrin pathway because the rigidifying effect of the intact antibody persists at alkaline pH, at which there is evidence that the ankyrin-band 3 link is largely dissociated. The large difference between the effects of saturating concentrations of the divalent and

  3. Peripheral blood stem cell mobilization failure.

    PubMed

    Kurnaz, Fatih; Kaynar, Leylagül

    2015-08-01

    Autologous hematopoietic stem cell transplantation (HSCT) is an important and often life saving treatment for many hematological malignancies and selected solid tumors. To rescue hematopoiesis after high-dose chemotherapy in autologous HSCT depends on maintaining sufficient stem cells. Hematopoietic stem cells and progenitor cells expressing CD34 in the BM are mobilized into the circulation with granulocyte-colony stimulating factor ± chemotherapy prior to autologous HSCT. One of the most important factors for success of autologous HSCT is hematopoietic stem cell (HSC) count. Minimum threshold for the engraftment of hematopoietic cells is accepted as 2 × 10(6) CD34 + cells/kg especially for platelet engraftment. Below this level it is defined as stem cell mobilization failure. There are several factors affecting stem cell mobilization: prior chemotherapy (such as fludarabine, melphalan, lenalidomide) and radiotherapy, age, type of disease, bone marrow cellularity. We tried to summarize the reasons of peripheral stem cell mobilization failure.

  4. Phenotypic differences of CD4(+) T cells in response to red blood cell immunization in transfused sickle cell disease patients.

    PubMed

    Vingert, Benoît; Tamagne, Marie; Habibi, Anoosha; Pakdaman, Sadaf; Ripa, Julie; Elayeb, Rahma; Galacteros, Frédéric; Bierling, Philippe; Ansart-Pirenne, Hélène; Bartolucci, Pablo; Noizat-Pirenne, France

    2015-06-01

    Alloimmunization against red blood cells (RBCs) is the main immunological risk associated with transfusion in patients with sickle cell disease (SCD). However, about 50-70% of SCD patients never get immunized despite frequent transfusion. In murine models, CD4(+) T cells play a key role in RBC alloimmunization. We therefore explored and compared the CD4(+) T-cell phenotypes and functions between a group of SCD patients (n = 11) who never became immunized despite a high transfusion regimen and a group of SCD patients (n = 10) who had become immunized (at least against Kidd antigen b) after a low transfusion regimen. We studied markers of CD4(+) T-cell function, including TLR, that directly control lymphocyte function, and their spontaneous cytokine production. We also tested responders for the cytokine profile in response to Kidd antigen b peptides. Low TLR2/TLR3 expression and, unexpectedly, strong expression of CD40 on CD4(+) T cells were associated with the nonresponder status, whereas spontaneous expression of IL-10 by CD4(+) T cells and weak Tbet expression were associated with the responder status. A Th17 profile was predominant in responders when stimulated by Jb(k) . These findings implicate CD4(+) T cells in alloimmunization in humans and suggest that they may be exploited to differentiate responders from nonresponders. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. The promise of fetal cells in maternal blood.

    PubMed

    Choolani, Mahesh; Mahyuddin, Aniza P; Hahn, Sinuhe

    2012-10-01

    Delaying childbirth increases the proportion of advanced maternal age pregnancies. This increases the number of pregnancies requiring invasive prenatal testing. Prenatal diagnosis of chromosomal aneuploidies and monogenic disorders requires fetal cells obtained through invasive procedures (i.e. chorionic villus sampling and amniocentesis). These procedures carry a risk of fetal loss, which causes anxiety to at-risk couples. Intact fetal cells entering maternal circulation have raised the possibility of non-invasive prenatal diagnosis. Rarity of fetal cells, however, has made it challenging. Fetal nucleated red blood cells are ideal candidate target cells because they have limited lifespan, contain true representation of fetal genotype, contain specific fetal cell identifiers (embryonic and fetal globins), and allow interrogation with chromosomal fluorescence in-situ hybridisation and possibly with array comparative genomic hybridisation. The utility of fetal nucleated red blood cells in non-invasive prenatal diagnosis has not reached clinical application because of the inconsistencies in enrichment strategies and rarity of cells.

  6. Cord Blood Mononuclear Cells Have a Potential to Produce NK Cells Using IL2Rg Cytokines

    PubMed Central

    Khaziri, Nahid; Mohammadi, Momeneh; Aliyari, Zeinab; Soleimani Rad, Jafar; Tayefi Nasrabadi, Hamid; Nozad Charoudeh, Hojjatollah

    2016-01-01

    Purpose: Although bone marrow represents the main site for NK cell development and also distinct thymic-dependentNK cell pathway was identified, the cytokines effect on the NK cell generation from cord blood is unclear. Studies were identified the role of cytokines in the regulation of bone marrow and thymic NK cells. Previous studies reported that IL15 are critical for bone marrow dependent and IL7 is important for thymic NK cells. It is remain unclear the cytokines influence on the expantion of NK cells in cord blood mononuclear cells. Methods: We evaluated cultured cord blood mononuclear cells suplememnted with combinations of cytokines using FACS in distinct time points. In this study, we presented the role of IL2, IL7 and IL15 as members of the common gamma receptor -chain (Il2rg) on the expansion NK cells from cord blood cells. Results: By investigating cord blood mononuclear cells in vitro , we demonstrated that IL2 and IL15 are important for expansion of NK cells. IL2 in comparision with IL15 has more influences in NK cell expansion. In contrast IL-7 is dispensable for NK cell generation in cord blood. Conclusion: Thus,IL-2Rg cytokines play complementary roles and are indispensable for homeostasis of NK cell development in cord blood. Probably these cytokines could help to use NK beneficials in engrafment of transplanted cells and Anti tumor activity of NK cells. PMID:27123412

  7. On-chip Extraction of Intracellular Molecules in White Blood Cells from Whole Blood.

    PubMed

    Choi, Jongchan; Hyun, Ji-chul; Yang, Sung

    2015-10-14

    The extraction of virological markers in white blood cells (WBCs) from whole blood--without reagents, electricity, or instruments--is the most important first step for diagnostic testing of infectious diseases in resource-limited settings. Here we develop an integrated microfluidic chip that continuously separates WBCs from whole blood and mechanically ruptures them to extract intracellular proteins and nucleic acids for diagnostic purposes. The integrated chip is assembled with a device that separates WBCs by using differences in blood cell size and a mechanical cell lysis chip with ultra-sharp nanoblade arrays. We demonstrate the performance of the integrated device by quantitatively analyzing the levels of extracted intracellular proteins and genomic DNAs. Our results show that compared with a conventional method, the device yields 120% higher level of total protein amount and similar levels of gDNA (90.3%). To demonstrate its clinical application to human immunodeficiency virus (HIV) diagnostics, the developed chip was used to process blood samples containing HIV-infected cells. Based on PCR results, we demonstrate that the chip can extract HIV proviral DNAs from infected cells with a population as low as 10(2)/μl. These findings suggest that the developed device has potential application in point-of-care testing for infectious diseases in developing countries.

  8. The flow of sickle-cell blood in the capillaries.

    PubMed Central

    Berger, S A; King, W S

    1980-01-01

    Oxygen tension levels and red cell velocities for the flow of sickle-cell blood in the capillaries are determined by using the Krogh model for oxygen transport and lubrication theory for the cell motion. The coupling and interaction between these arises from the red cell compliance, which is assumed to vary with the oxygen concentration. Microsieving data is used to establish an upper bound for this relationship. Calculations are carried out for a range of capillary sizes, taking into account the rightward shift of the oxyhemoglobin dissociation curve and the reduced hematocrit of sickle-cell blood, and are compared to, as a base case, the flow of normal blood under normal pressure gradient. The results indicate that under normal pressure gradients the oxygen tensions and cell velocities for sickle blood are considerably higher than for normal blood, thus acting against the tendency for cells to sickle, or significantly change their rheological properties, in the capillaries. Under reduced pressure gradients, however, the concentrations and velocities drop dramatically, adding to the likelihood of such shape or flow property changes. PMID:7260242

  9. Shear induced diffusion in a red blood cell suspension

    NASA Astrophysics Data System (ADS)

    Podgorski, Thomas; Grandchamp, Xavier; Srivastav, Aparna; Coupier, Gwennou

    2012-11-01

    In the microcirculation, blood exhibits an inhomogeneous structure which results in the well know Fahraeus-Lindqvist effect : the apparent viscosity decreases when the diameter of the capillary decreases due to the formation of a marginal cell depletion layer (known as plasma skimming). This structure is a consequence of several phenomena, which include i) the migration of cells aways from walls due to lift forces and gradients of shear and ii) shear induced diffusion due to collisions and interactions among cells. We investigated these phenomena through experiments in simple shear and microchannel flows, with dilute suspensions of vesicles and blood cells. Pairwise interactions between suspended objects result in non-linear and flow-dependent diffusion, whose properties have been measured in different experiments for vesicles and blood cells. The injection of a sheet of concentrated blood cell suspension in a microchannel with a rectangular cross-section allows, through the measurement of its widening along the channel, to measure the diffusivity of blood cells, both in the local plane of shear and in the vorticity direction.

  10. Mutation assays involving blood cells that metabolize toxic substances

    DOEpatents

    Crespi, Charles L.; Thilly, William G.

    1999-01-01

    The present invention pertains to a line of human blood cells which have high levels of oxidative activity (such as oxygenase, oxidase, peroxidase, and hydroxylase activity). Such cells grow in suspension culture, and are useful to determine the mutagenicity of xenobiotic substances that are metabolized into toxic or mutagenic substances. The invention also includes mutation assays using these cells, and other cells with similar characteristics.

  11. Mutation assays involving blood cells that metabolize toxic substances

    DOEpatents

    Crespi, C.L.; Thilly, W.G.

    1999-08-10

    The present invention pertains to a line of human blood cells which have high levels of oxidative activity (such as oxygenase, oxidase, peroxidase, and hydroxylase activity). Such cells grow in suspension culture, and are useful to determine the mutagenicity of xenobiotic substances that are metabolized into toxic or mutagenic substances. The invention also includes mutation assays using these cells, and other cells with similar characteristics. 3 figs.

  12. Blood cell manufacture: current methods and future challenges.

    PubMed

    Timmins, Nicholas E; Nielsen, Lars K

    2009-07-01

    Blood transfusion depends on availability of donor material, and concerns over supply and safety have spurred development of methods to manufacture blood from stem cells. Current methods could theoretically yield therapeutic doses of red blood cells (RBCs) and platelets. However, due to the very large number of cells required to have any impact on supply (currently 10(19) RBC/year in the US), realization of routine manufacture faces significant challenges. Current yields are orders of magnitude too low for production of meaningful quantities, and the physical scale of the problem is a challenge in itself. We discuss these challenges in relation to current methods and how it might be possible to realize limited 'blood pharming' of neutrophils in the near future.

  13. Laser-photophoretic migration and fractionation of human blood cells.

    PubMed

    Monjushiro, Hideaki; Tanahashi, Yuko; Watarai, Hitoshi

    2013-05-13

    Laser photophoretic migration behavior of human blood cells in saline solution was investigated under the irradiation of Nd:YAG laser beam (532 nm) in the absence and the presence of the flow in a fused silica capillary. Red blood cells (RBC) were migrated faster than white blood cells (WBC) and blood pellets to the direction of propagation of laser light. The observed photophoretic velocity of RBC was about 11 times faster than those of others. This was understood from the larger photophoretic efficiency of RBC than that of WBC, which was simulated based on the Mie scattering theory. Furthermore, it was found that, during the photophoretic migration, RBCs spontaneously orientated parallel to the migration direction so as to reduce the drag force. Finally, it was demonstrated that RBC and WBC were separated in a micro-channel flow system by the laser photophoresis.

  14. Red blood cell aggregate flux in a bifurcating microchannel.

    PubMed

    Kaliviotis, E; Pasias, D; Sherwood, J M; Balabani, S

    2017-10-01

    Red blood cell aggregation plays a key role in microcirculatory flows, however, little is known about the transport characteristics of red blood cell aggregates in branching geometries. This work reports on the fluxes of red blood cell aggregates of various sizes in a T-shaped microchannel, aiming to clarify the effects of different flow conditions in the outlet branches of the channel. Image analysis techniques, were utilised, and moderately aggregating human red blood cell suspensions were tested in symmetric (∼50-50%) and asymmetric flow splits through the two outlet (daughter) branches. The results revealed that the flux decreases with aggregate size in the inlet (parent) and daughter branches, mainly due to the fact that the number of larger structures is significantly smaller than that of smaller structures. However, when the flux in the daughter branches is examined relative to the aggregate size flux in the parent branch an increase with aggregate size is observed for a range of asymmetric flow splits. This increase is attributed to size distribution and local concentration changes in the daughter branches. The results show that the flow of larger aggregates is not suppressed downstream of a bifurcation, and that blood flow is maintained, for physiological levels of red blood cell aggregation. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

  15. Hematologic Assessment in Pet Rats, Mice, Hamsters, and Gerbils: Blood Sample Collection and Blood Cell Identification.

    PubMed

    Lindstrom, Nicole M; Moore, David M; Zimmerman, Kurt; Smith, Stephen A

    2015-09-01

    Hamsters, gerbils, rats, and mice are presented to veterinary clinics and hospitals for prophylactic care and treatment of clinical signs of disease. Physical examination, history, and husbandry practice information can be supplemented greatly by assessment of hematologic parameters. As a resource for veterinarians and their technicians, this article describes the methods for collection of blood, identification of blood cells, and interpretation of the hemogram in mice, rats, gerbils, and hamsters.

  16. Hematologic assessment in pet rats, mice, hamsters, and gerbils: blood sample collection and blood cell identification.

    PubMed

    Lindstrom, Nicole M; Moore, David M; Zimmerman, Kurt; Smith, Stephen A

    2015-01-01

    Hamsters, gerbils, rats, and mice are presented to veterinary clinics and hospitals for prophylactic care and treatment of clinical signs of disease. Physical examination, history, and husbandry practice information can be supplemented greatly by assessment of hematologic parameters. As a resource for veterinarians and their technicians, this article describes the methods for collection of blood, identification of blood cells, and interpretation of the hemogram in mice, rats, gerbils, and hamsters.

  17. Cord blood transplants for SCID: better B-cell engraftment?

    PubMed

    Chan, Wan-Yin; Roberts, Robert Lloyd; Moore, Theodore B; Stiehm, E Richard

    2013-01-01

    Hematopoietic stem-cell transplantation is the treatment of choice for severe combined immunodeficiency (SCID). Despite successful T-cell engraftment in transplanted patients, B-cell function is not always achieved; up to 58% of patients require immunoglobulin therapy after receiving haploidentical transplants. We report 2 half-sibling males with X-linked γ-chain SCID treated with different sources of stem cells. Sibling 1 was transplanted with T-cell-depleted haploidentical maternal bone marrow and sibling 2 was transplanted with 7/8 human leukocyte antigen-matched unrelated umbilical cord blood. Both patients received pretransplant conditioning and posttransplant graft-versus-host-disease prophylaxis. B-cell engraftment and function was achieved in sibling 1 but not in sibling 2. This disparate result is consistent with a review of 19 other SCID children who received cord blood transplants. B-cell function, as indicated by no need for immunoglobulin therapy, was restored in 42% of patients given haploidentical transplants and in 68% of patients given matched unrelated donor transplants compared with 80% of patients given cord blood transplants. Cord blood is an alternative source of stem cells for transplantation in children with SCID and has a higher likelihood of B-cell reconstitution.

  18. Malaria and Human Red Blood Cells

    PubMed Central

    Mohandas, Narla; An, Xiuli

    2013-01-01

    Invasion by the malaria parasite, P. falciparum brings about extensive changes in the host red cells. These include loss of the normal discoid shape, increased rigidity of the membrane, elevated permeability to a wide variety of ionic and other species, and increased adhesiveness, most notably to endothelial surfaces. These effects facilitate survival of the parasite within the host cell and tend to increase the virulence of disease that include cerebral malaria and anemia. Numerous proteins secreted by the internalized parasite and interaction with red cell membrane proteins are responsible for the changes occurring to the host cell. Anemia a serious clinical manifestation of malaria is due to increased destruction of both infected and uninfected red cells due to membrane alterations, as well as ineffective erythropoiesis. There is very good evidence that various red cell disorders including hemoglobinopathies and hereditary ovalocytosis decrease the virulence of disease following parasite infection. A number of mechanism(s) are likely responsible for the protective effect of various red cell abnormalities including decreased invasion, impaired intraerythrocytic development of the parasites and altered interaction between exported parasite proteins and the red cell membrane skeleton. PMID:22965173

  19. Malaria and human red blood cells.

    PubMed

    Mohandas, Narla; An, Xiuli

    2012-11-01

    Invasion by the malaria parasite, Plasmodium falciparum, brings about extensive changes in the host red cells. These include loss of the normal discoid shape, increased rigidity of the membrane, elevated permeability to a wide variety of ionic and other species and increased adhesiveness, most notably to endothelial surfaces. These effects facilitate survival of the parasite within the host cell and tend to increase the virulence of disease that includes cerebral malaria and anemia. Numerous proteins secreted by the internalized parasite and interacting with red cell membrane proteins are responsible for the changes occurring to the host cell. Anemia, a serious clinical manifestation of malaria, is due to increased destruction of both infected and uninfected red cells due to membrane alterations, as well as ineffective erythropoiesis. There is very good evidence that various red cell disorders including hemoglobinopathies and hereditary ovalocytosis decrease the virulence of disease following parasite infection. A number of mechanism(s) are likely responsible for the protective effect of various red cell abnormalities including decreased invasion, impaired intraerythrocytic development of the parasites and altered interaction between exported parasite proteins and the red cell membrane skeleton.

  20. [Simplified preparation of test-red blood cells for ABO blood grouping in a laboratory in Madagascar].

    PubMed

    Rasamiravaka, T; Andrianarivelo, A M; Ramarison, G; Rakoto-Alson, A O; Rasamindrakotroka, A

    2011-10-01

    To ensure self-sufficiency and lower costs associated with reagent red blood cells, some medical laboratories produce their own test-red blood cells for plasma ABO blood grouping. However, given the vital importance of blood goup testing, it is essential to verify the reliability of these cells. The purpose of this study was to assess the quality of laboratory-made ABO test-red blood cells. This study comparing house made and commercially available test-red blood cells was carried out at the Medical Biology Training and Research Laboratory in Madagascar. This laboratory is attended by people wishing to obtain their blood group card. In this population, no discrepancy was found between the red cell and plasma tests. Comparison of test-red blood cells with commercially available reagent red blood cells showed no difference in reactivity in the first four days of conservation. However a decrease in the reactivity of house made cells appeared on the 5th day. House made red blood cells are costless than commercially available reagent red blood cells mainly due to the simplified method of preparation. However, since laboratory-made cells progressivley lose antigenic reactivity quicly, production must be repeated regularly and good internal quality control is necessary to ensure reliability.

  1. Filter Characteristics Influencing Circulating Tumor Cell Enrichment from Whole Blood

    PubMed Central

    Beck, Markus; Terstappen, Leon W. M. M.

    2013-01-01

    A variety of filters assays have been described to enrich circulating tumor cells (CTC) based on differences in physical characteristics of blood cells and CTC. In this study we evaluate different filter types to derive the properties of the ideal filter for CTC enrichment. Between 0.1 and 10 mL of whole blood spiked with cells from tumor cell lines were passed through silicon nitride microsieves, polymer track-etched filters and metal TEM grids with various pore sizes. The recovery and size of 9 different culture cell lines was determined and compared to the size of EpCAM+CK+CD45−DNA+ CTC from patients with metastatic breast, colorectal and prostate cancer. The 8 µm track-etched filter and the 5 µm microsieve had the best performance on MDA-231, PC3-9 and SKBR-3 cells, enriching >80% of cells from whole blood. TEM grids had poor recovery of ∼25%. Median diameter of cell lines ranged from 10.9–19.0 µm, compared to 13.1, 10.7, and 11.0 µm for breast, prostate and colorectal CTC, respectively. The 11.4 µm COLO-320 cell line had the lowest recovery of 17%. The ideal filter for CTC enrichment is constructed of a stiff, flat material, is inert to blood cells, has at least 100,000 regularly spaced 5 µm pores for 1 ml of blood with a ≤10% porosity. While cell size is an important factor in determining recovery, other factors must be involved as well. To evaluate a filtration procedure, cell lines with a median size of 11–13 µm should be used to challenge the system. PMID:23626725

  2. Filter characteristics influencing circulating tumor cell enrichment from whole blood.

    PubMed

    Coumans, Frank A W; van Dalum, Guus; Beck, Markus; Terstappen, Leon W M M

    2013-01-01

    A variety of filters assays have been described to enrich circulating tumor cells (CTC) based on differences in physical characteristics of blood cells and CTC. In this study we evaluate different filter types to derive the properties of the ideal filter for CTC enrichment. Between 0.1 and 10 mL of whole blood spiked with cells from tumor cell lines were passed through silicon nitride microsieves, polymer track-etched filters and metal TEM grids with various pore sizes. The recovery and size of 9 different culture cell lines was determined and compared to the size of EpCAM+CK+CD45-DNA+ CTC from patients with metastatic breast, colorectal and prostate cancer. The 8 µm track-etched filter and the 5 µm microsieve had the best performance on MDA-231, PC3-9 and SKBR-3 cells, enriching >80% of cells from whole blood. TEM grids had poor recovery of ∼25%. Median diameter of cell lines ranged from 10.9-19.0 µm, compared to 13.1, 10.7, and 11.0 µm for breast, prostate and colorectal CTC, respectively. The 11.4 µm COLO-320 cell line had the lowest recovery of 17%. The ideal filter for CTC enrichment is constructed of a stiff, flat material, is inert to blood cells, has at least 100,000 regularly spaced 5 µm pores for 1 ml of blood with a ≤10% porosity. While cell size is an important factor in determining recovery, other factors must be involved as well. To evaluate a filtration procedure, cell lines with a median size of 11-13 µm should be used to challenge the system.

  3. Isolation of nucleated red blood cells in maternal blood for Non-invasive prenatal diagnosis.

    PubMed

    Byeon, Yeongje; Ki, Chang-Seok; Han, Ki-Ho

    2015-12-01

    This paper introduces a two-step cascade enrichment method for isolating nucleated red blood cells (NRBCs) in maternal blood. The two-step enrichment platform consists of a positive enrichment process based on a red blood cell (RBC) hyperaggregation method and a negative enrichment process using microfluidic technology. An analytical evaluation using blood samples from patients with leukemia showed that the while blood cell (WBC) depletion and NRBC loss rates of the positive enrichment process were 93.98 % and 6.02 %, respectively. Through the two-step cascade enrichment method, 1-396 NRBCs and only 0-6 WBCs were isolated from 1 mL of 18 maternal blood samples. Experimental results also showed that the WBC depletion rate of the proposed two-step method was more than 625,000-fold, and the purity of enriched NRBCs ranged from 20 % to 100 %. Furthermore, SRY (the sex-determining region of the Y chromosome) genes were detected in enriched NRBCs, thereby demonstrating that enriched NRBCs contain fetus-derived NRBCs.

  4. Effect of red blood cell aggregation and sedimentation on optical coherence tomography signals from blood samples

    NASA Astrophysics Data System (ADS)

    Kirillin, M. Yu; Priezzhev, A. V.; Tuchin, V. V.; Wang, R. K.; Myllylä, R.

    2005-08-01

    In this work, Monte Carlo simulation is used to obtain model optical coherence tomography (OCT) signals from a horizontally orientated blood layer at different stages of red blood cell (RBC) aggregation and sedimentation processes. The parameters for aggregating and sedimenting blood cells were chosen based on the data available from the literature and our earlier experimental studies. We consider two different cases: a suspension of washed RBCs in physiological solution (where aggregation does not take place) and RBCs in blood plasma (which provides necessary conditions for aggregation). Good agreement of the simulation results with the available experimental data shows that the chosen optical parameters are reasonable. The dependence of the numbers of photons contributing to the OCT signal on the number of experienced scattering events was analysed for each simulated signal. It was shown that the maxima of these dependences correspond to the peaks in the OCT signals related to the interfaces between the layers of blood plasma and blood cells. Their positions can be calculated from the optical thicknesses of the layers, and the absorption and scattering coefficients of the media.

  5. Isolation of fetal nucleated red blood cells from maternal blood in normal and aneuploid pregnancies.

    PubMed

    Prieto, Belén; Cándenas, Mercedes; Venta, Rafael; Ladenson, Jack H; Alvarez, Francisco V

    2002-07-01

    Fetal nucleated red blood cells (NRBC) have been widely reported in maternal blood during pregnancy. However, there is no consensus with regard to their presence in all pregnancies. Therefore, the usefulness of developing a fetal NRBC-based noninvasive method suitable for clinical prenatal diagnosis remains uncertain. Fluorescence in situ hybridization (FISH) method was used to evaluate the ability of one of our own monoclonal antibodies (mAb), 2B7.4, to isolate fetal NRBC from maternal blood by magnetic activated cell sorting (MACS). Our mAb was able to isolate from 25 to 822 NRBC from all of the 45 maternal blood samples included in this study. A correct diagnosis was achieved in 21 out of 24 pregnancies carrying trisomic fetuses (87.5%), with a fetal/maternal NRBC frequency of 8.4%. In contrast, a significantly lower percentage of fetal NRBC (0.2%) was observed in 22% of pregnancies carrying a chromosomally normal male fetus, that were correctly predicted. In conclusion, using 2B7.4 mAb we succeeded in isolating NRBC from the maternal blood samples, but most of the isolated cells were maternal in origin. Nevertheless, a higher number of fetal NRBC was found in the peripheral blood of pregnant women carrying aneuploid fetuses, which could allow development of a screening method for prenatal diagnosis of fetal aneuploidies.

  6. Blood thixotropy in patients with sickle cell anaemia: role of haematocrit and red blood cell rheological properties.

    PubMed

    Vent-Schmidt, Jens; Waltz, Xavier; Romana, Marc; Hardy-Dessources, Marie-Dominique; Lemonne, Nathalie; Billaud, Marie; Etienne-Julan, Maryse; Connes, Philippe

    2014-01-01

    We compared the blood thixotropic/shear-thinning properties and the red blood cells' (RBC) rheological properties between a group of patients with sickle cell anaemia (SS) and healthy individuals (AA). Blood thixotropy was determined by measuring blood viscosity with a capillary viscometer using a "loop" protocol: the shear rate started at 1 s-1 and increased progressively to 922 s-1 and then re-decreased to the initial shear rate. Measurements were performed at native haematocrit for the two groups and at 25% and 40% haematocrit for the AA and SS individuals, respectively. RBC deformability was determined by ektacytometry and RBC aggregation properties by laser backscatter versus time. AA at native haematocrit had higher blood thixotropic index than SS at native haematocrit and AA at 25% haematocrit. At 40% haematocrit, SS had higher blood thixotropic index than AA. While RBC deformability and aggregation were lower in SS than in AA, the strength of RBC aggregates was higher in the former population. Our results showed that 1) anaemia is the main modulator of blood thixtropy and 2) the low RBC deformability and high RBC aggregates strength cause higher blood thixotropy in SS patients than in AA individuals at 40% haematocrit, which could impact blood flow in certain vascular compartments.

  7. Association of heart rate with blood pressure variability: implications for blood pressure measurement.

    PubMed

    Cahan, Amos; Ben-Dov, Iddo Z; Bursztyn, Michael

    2012-03-01

    Antihypertensive β-blocker use is associated with greater intervisit blood pressure variability (BPV) and with less favorable outcomes compared to other antihypertensive agents. A theoretical model demonstrated that accuracy and precision of BP measurement are affected by heart rate (HR) at a constant cuff deflation rate. We aimed to examine the empirical relationship between HR and BPV in a clinical setting. Intratracing variability in ambulatory BP monitoring (ABPM) were analyzed in search of a link between BPV and HR. BPV was expressed as standard deviation (s.d.), coefficient of variation (CV), and variability independent of the mean (VIM). In a dataset of 4,693 subjects, HR was inversely associated with BPV and independently explained 1.3% of between-subject variation in s.d. of awake systolic BP (1.5% of CV and VIM). Linear regression suggested 0.5 mm Hg increase in s.d. of systolic BP per 10 beats per minute (bpm) decrease in HR. In a subset of 1,019 patients with available data on medications, HR was independently and inversely related with awake systolic BPV (P < 0.0001), more so in diuretic (P < 0.050) and renin-angiotensin system antagonists-treated (P < 0.050) patients. Associations of β-blockade with increased BPV were abolished by model-adjustment for HR. In another subset of patients who were monitored twice (n = 635), HR had a mild (0.6%) but significant (P < 0.05) inverse contribution to the change in awake systolic BPV between repeated monitoring. Ambulatory BPV is inversely related to HR and is not increased in referred patients treated with β-blockers after correction for HR. © 2012 American Journal of Hypertension, Ltd.

  8. Image analysis of nucleated red blood cells.

    PubMed

    Zajicek, G; Shohat, M; Melnik, Y; Yeger, A

    1983-08-01

    Bone marrow smears stained with Giemsa were scanned with a video camera under computer control. Forty-two cells representing the six differentiation classes of the red bone marrow were sampled. Each cell was digitized into 70 X 70 pixels, each pixel representing a square area of 0.4 micron2 in the original image. The pixel gray values ranged between 0 and 255. Zero stood for white, 255 represented black, while the numbers in between stood for the various shades of gray. After separation and smoothing the images were processed with a Sobel operator outlining the points of steepest gray level change in the cell. These points constitute a closed curve denominated as inner cell boundary, separating the cell into an inner and an outer region. Two types of features were extracted from each cell: form features, e.g., area and length, and gray level features. Twenty-two features were tested for their discriminative merit. After selecting 16, the discriminant analysis program classified correctly all 42 cells into the 6 classes.

  9. Participation of blood vessel cells in human adaptive immune responses.

    PubMed

    Pober, Jordan S; Tellides, George

    2012-01-01

    Circulating T cells contact blood vessels either when they extravasate across the walls of microvessels into inflamed tissues or when they enter into the walls of larger vessels in inflammatory diseases such as atherosclerosis. The blood vessel wall is largely composed of three cell types: endothelial cells lining the entire vascular tree; pericytes supporting the endothelium of microvessels; and smooth muscle cells forming the bulk of large vessel walls. Each of these cell types interacts with and alters the behavior of infiltrating T cells in different ways, making these cells active participants in the processes of immune-mediated inflammation. In this review, we compare and contrast what is known about the nature of these interactions in humans. Copyright © 2011 Elsevier Ltd. All rights reserved.

  10. Cryopreserved red blood cells are superior to standard liquid red blood cells.

    PubMed

    Hampton, David A; Wiles, Connor; Fabricant, Loïc J; Kiraly, Laszlo; Differding, Jerome; Underwood, Samantha; Le, Dinh; Watters, Jennifer; Schreiber, Martin A

    2014-07-01

    Liquid preserved packed red blood cell (LPRBC) transfusions are used to treat anemia and increase end-organ perfusion. Throughout their storage duration, LPRBCs undergo biochemical and structural changes collectively known as the storage lesion. These changes adversely affect perfusion and oxygen off-loading. Cryopreserved RBCs (CPRBC) can be stored for up to 10 years and potentially minimize the associated storage lesion. We hypothesized that CPRBCs maintain a superior biochemical profile compared with LPRBCs. This was a prospective, randomized, double-blinded study. Adult trauma patients with an Injury Severity Score (ISS) greater than 4 and an anticipated 1-U to 2-U transfusion of PRBCs were eligible. Enrolled patients were randomized to receive either CPRBCs or LPRBCs. Serum proteins (haptoglobin, serum amyloid P, and C-reactive protein), proinflammatory and anti-inflammatory cytokines, d-dimer, nitric oxide, and 2,3-DPG concentrations were analyzed. Mann-Whitney U-test and Wilcoxon rank sum test were used to assess significance (p < 0.05). Fifty-seven patients were enrolled (CPRBC, n = 22; LPRBC, n = 35). The LPRBC group's final interleukin 8, tumor necrosis factor α, and d-dimer concentrations were elevated compared with their pretransfusion values (p < 0.05). After the second transfused units, 2,3-DPG was higher in the patients receiving CPRBCs (p < 0.05); this difference persisted throughout the study. Finally, serum protein concentrations were decreased in the transfused CPRBC units compared with LPRBC (p < 0.01). CPRBC transfusions have a superior biochemical profile: an absent inflammatory response, attenuated fibrinolytic state, and increased 2,3-DPG. A blood banking system using both storage techniques will offer the highest-quality products to critically injured patients virtually independent of periodic changes in donor availability and transfusion needs. Therapeutic study, level II.

  11. Full dynamics of a red blood cell in shear flow.

    PubMed

    Dupire, Jules; Socol, Marius; Viallat, Annie

    2012-12-18

    At the cellular scale, blood fluidity and mass transport depend on the dynamics of red blood cells in blood flow, specifically on their deformation and orientation. These dynamics are governed by cellular rheological properties, such as internal viscosity and cytoskeleton elasticity. In diseases in which cell rheology is altered genetically or by parasitic invasion or by changes in the microenvironment, blood flow may be severely impaired. The nonlinear interplay between cell rheology and flow may generate complex dynamics, which remain largely unexplored experimentally. Under simple shear flow, only two motions, "tumbling" and "tank-treading," have been described experimentally and relate to cell mechanics. Here, we elucidate the full dynamics of red blood cells in shear flow by coupling two videomicroscopy approaches providing multidirectional pictures of cells, and we analyze the mechanical origin of the observed dynamics. We show that contrary to common belief, when red blood cells flip into the flow, their orientation is determined by the shear rate. We discuss the "rolling" motion, similar to a rolling wheel. This motion, which permits the cells to avoid energetically costly deformations, is a true signature of the cytoskeleton elasticity. We highlight a hysteresis cycle and two transient dynamics driven by the shear rate: an intermittent regime during the "tank-treading-to-flipping" transition and a Frisbee-like "spinning" regime during the "rolling-to-tank-treading" transition. Finally, we reveal that the biconcave red cell shape is highly stable under moderate shear stresses, and we interpret this result in terms of stress-free shape and elastic buckling.

  12. Management strategies for poor peripheral blood stem cell mobilization.

    PubMed

    Moog, Rainer

    2008-06-01

    Peripheral blood stem cells (PBSC) have nearly replaced bone marrow (BM) as the preferred source of hematopoietic rescue for patients undergoing high-dose chemotherapy. However, some patients fail to mobilize sufficient numbers of PBSC into the peripheral blood thereby putting high-dose chemotherapy at risk. The present article reviews mobilization of PBSC with a special focus on poor mobilizers. Under steady-state conditions less than 0.05% of the white blood cells (WBC) are CD34+ cells. Chemotherapy results in a 5-15-fold increase of PBSC. Combining chemotherapy and growth factors increases CD34+ cells up to 6% of WBC. Several factors affect the mobilization of PBSC: age, gender, type of growth factor, dose of the growth factor and in the autologous setting patient's diagnosis, chemotherapy regimen and number of previous chemotherapy cycles or radiation. Poor mobilizers are defined as patients with less than 10 CD34+ cells/mul in the peripheral blood during mobilization. Promising approaches for those patients rely on remobilization, use of high doses of granulocyte-colony stimulating factor (G-CSF), or the combination of G-CSF and granulocyte macrophage (GM)-CSF, which successfully mobilized the majority of poor mobilizing patients. New agents such as long lasting variants of G-CSF and CXCR4 antagonists are at the horizon and studied in clinical trials as mobilizing agents. Muscle and bone pain are frequent adverse events in stem cell mobilization but are usually tolerated under the use of analgesics. Large volume apheresis (LVL) with a processed volume of more than 4-fold patient's blood volume is an approach to increase the CD34+ yield in patients with low CD34+ pre-counts resulting in higher yields of CD34+ cells for transplantation. Processing of more blood in LVL is achieved by an increase of the blood flow rate and an altered anticoagulation regimen with the occurrence of more citrate reactions.

  13. Control of red blood cell mass during spaceflight

    NASA Technical Reports Server (NTRS)

    Lane, H. W.; Alfrey, C. P.; Driscoll, T. B.; Smith, S. M.; Nyquist, L. E.

    1996-01-01

    Data are reviewed from twenty-two astronauts from seven space missions in a study of red blood cell mass. The data show that decreased red cell mass in all astronauts exposed to space for more than nine days, although the actual dynamics of mass changes varies with flight duration. Possible mechanisms for these changes, including alterations in erythropoietin levels, are discussed.

  14. Observation of dynamic subdomains in red blood cells.

    PubMed

    Popescu, Gabriel; Badizadegan, Kamran; Dasari, Ramachandra R; Feld, Michael S

    2006-01-01

    We quantify the nanoscale structure and low-frequency dynamics associated with live red blood cells. The membrane displacements are measured using quantitative phase images provided by Fourier phase microscopy, with an average path-length stability of 0.75 nm over 45 min. The results reveal the existence of dynamic, independent subdomains across the cells that fluctuate at various dominant frequencies.

  15. Control of red blood cell mass during spaceflight

    NASA Technical Reports Server (NTRS)

    Lane, H. W.; Alfrey, C. P.; Driscoll, T. B.; Smith, S. M.; Nyquist, L. E.

    1996-01-01

    Data are reviewed from twenty-two astronauts from seven space missions in a study of red blood cell mass. The data show that decreased red cell mass in all astronauts exposed to space for more than nine days, although the actual dynamics of mass changes varies with flight duration. Possible mechanisms for these changes, including alterations in erythropoietin levels, are discussed.

  16. Myeloid Suppressor Cells Accumulate and Regulate Blood Pressure in Hypertension.

    PubMed

    Shah, Kandarp H; Shi, Peng; Giani, Jorge F; Janjulia, Tea; Bernstein, Ellen A; Li, You; Zhao, Tuantuan; Harrison, David G; Bernstein, Kenneth E; Shen, Xiao Z

    2015-10-23

    Chronic inflammation is a major contributor to the progressive pathology of hypertension, and T-cell activation is required for the genesis of hypertension. However, the precise role of myeloid cells in this process is unclear. To characterize and understand the role of peripheral myeloid cells in the development of hypertension. We examined myeloid cells in the periphery of hypertensive mice and found that increased numbers of CD11b(+)Gr1(+) myeloid cells in blood and the spleen are a characteristic of 3 murine models of experimental hypertension (angiotensin II, L-NG-nitroarginine methyl ester, and high salt). These cells express surface markers and transcription factors associated with immaturity and immunosuppression. Also, they produce hydrogen peroxide to suppress T-cell activation. These are characteristics of myeloid-derived suppressor cells (MDSCs). Depletion of hypertensive MDSCs increased blood pressure and renal inflammation. In contrast, adoptive transfer of wild-type MDSCs to hypertensive mice reduced blood pressure, whereas the transfer of nicotinamide adenine dinucleotide phosphate oxidase 2-deficient MDSCs did not. The accumulation of MDSCs is a characteristic of experimental models of hypertension. MDSCs limit inflammation and the increase of blood pressure through the production of hydrogen peroxide. © 2015 American Heart Association, Inc.

  17. THE RETICULAR MATERIAL OF DEVELOPING BLOOD CELLS

    PubMed Central

    Cowdry, Edmund V.

    1921-01-01

    Erythroblasts, leucocytes, and lymphocytes resemble other cells of the body in containing a restricted area of fluidity in their cytoplasm. In special preparations this fluid appears in the form of a more or less complicated reticulum which seems to be continually but slowly changing in shape. For convenience the fluid may provisionally be referred to as reticular material, emphasis being laid on its composition rather than its form. As a working hypothesis it is safe to assume that the chemical and physical properties of this material vary in cells of different kinds as well as in different stages in the activity of the same cell. The conclusion that it is "identical" in different cells, because the present crude methods of technique reveal no fundamental differences, would be as incorrect as the statement that the serum of different animals is identical, because no difference is observed on microscopic examination. PMID:19868474

  18. ABO blood group mismatched hematopoietic stem cell transplantation.

    PubMed

    Tekgündüz, Sibel Akpınar; Özbek, Namık

    2016-02-01

    Apart from solid organ transplantations, use of ABO-blood group mismatched (ABO-mismatched) donors is acceptable in hematopoietic stem cell transplantation (HSCT) patients. About 20-40% of allogeneic HSCT recipients will receive grafts from ABO-mismatched donors. ABO incompatible HSCT procedures are associated with immediate and late consequences, including but not restricted to acute or delayed hemolytic reactions, delayed red blood cell recovery, pure red cell aplasia and graft-versus-host disease. This review summarizes the current knowledge about consequences of ABO-mismatched HSCT in terms of associated complications and will evaluate its impact on important outcome parameters of HSCT.

  19. Human white blood cells contain cyclobutyl pyrimidine dimer photolyase

    SciTech Connect

    Sutherland, B.M.; Bennett, P.V.

    1995-10-10

    Although enzymatic photoreactivation of cyclobutyl pyrimidine dimers in DNA is present in almost all organisms, its presence in placental mammals is controversial. We tested human white blood cells for photolyase by using three defined DNAs (suprecoiled pET-2, nonsupercoiled bacteriphage {lambda}, and a defined-sequence 287-bp oligonucleotide), two dimer-specific endonucleases (T4 endonuclease V and UV endonuclease from Micrococcus luteus), and three assay methods. We show that human white blood cells contain photolyase that can photorepair pyrimidine dimers in defined supercoiled and linear DNAs and in a 287-bp oligonucleotide and that human photolyase is active on genomic DNA in intact human cells. 44 refs., 3 figs.

  20. Rapid white blood cell detection for peritonitis diagnosis

    NASA Astrophysics Data System (ADS)

    Wu, Tsung-Feng; Mei, Zhe; Chiu, Yu-Jui; Cho, Sung Hwan; Lo, Yu-Hwa

    2013-03-01

    A point-of-care and home-care lab-on-a-chip (LoC) system that integrates a microfluidic spiral device as a concentrator with an optical-coding device as a cell enumerator is demonstrated. The LoC system enumerates white blood cells from dialysis effluent of patients receiving peritoneal dialysis. The preliminary results show that the white blood cell counts from our system agree well with the results from commercial flow cytometers. The LoC system can potentially bring significant benefits to end stage renal disease (ESRD) patients that are on peritoneal dialysis (PD).

  1. Freeze-Dried Human Red Blood Cells

    DTIC Science & Technology

    1992-01-15

    outlined in our November progress report had been successfully used to repair damage incurred by RBC during hypotonic lysis ( referencesl and 2). The...reconstitution. Figures IA-IF show the osmotic deformability profiles of our thawed red cell preparation. Note the well defined hypotonic and hypertonic...upon rehydration. The osmotic deformability profiles of the reconstituted lyophilized cells are also nearly normal with well defined hypotonic and

  2. Red blood cells transfusion in intensive care unit.

    PubMed

    Volpato, Solange Emanuelle; Ferreira, Jovino Dos Santos; Ferreira, Vera Lúcia Paes Cavalcanti; Ferreira, David Cavalcanti

    2009-12-01

    The anemia is a common problem upon admission of the patients in the intensive care unit being the red blood cell transfusion a frequent therapeutic. The causes of anemia in critical patients who under go red blood cell transfusion are several: acute loss of blood after trauma, gastrointestinal hemorrhage, surgery amongst others. Currently, few studies are available regarding the use of blood components in patients at intensive care unit. Although blood transfusions are frequent in intensive care unit, the optimized criteria for handling are not clearly defined, with no available guidelines. To analyze the clinical indications of the use of the red blood cell in the intensive care unit. The clinical history of the patients admitted in the intensive care unit were analyzed, revisiting which had have red blood cell transfusion in the period between January 1st 2005 and December 31 2005. The study was accepted by the Research Ethics Committee - Comitê de Ética em Pesquisa (CEP) - of the University of South of Santa Catarina (UNISUL). The transfusion rate was 19,33, and the majority of the patients were of the male gender. Their age prevalence was of 60 years old or older. The mortality rate among patients who under went red blood cell transfusion died was of 38,22%. The transfusions criterias were low serum hemoglobin (78%) and the hemoglobin pre - transfusion was 8,11 g/dL. Politrauma and sepsis/sepsis chock were the pre diagnosis criteria. A low hemoglobin level is the main clinical criteria with average hemoglobin pre - transfusion was 8,11 g/dL.

  3. Spatial Distributions of Red Blood Cells Significantly Alter Local Haemodynamics

    PubMed Central

    Sherwood, Joseph M.; Holmes, David; Kaliviotis, Efstathios; Balabani, Stavroula

    2014-01-01

    Although bulk changes in red blood cell concentration between vessels have been well characterised, local distributions are generally overlooked. Red blood cells aggregate, deform and migrate within vessels, forming heterogeneous distributions which have considerable effect on local haemodynamics. The present study reports data on the local distribution of human red blood cells in a sequentially bifurcating microchannel, representing the branching geometry of the microvasculature. Imaging methodologies with simple extrapolations are used to infer three dimensional, time-averaged velocity and haematocrit distributions under a range of flow conditions. Strong correlation between the bluntness of the velocity and haematocrit profiles in the parent branch of the geometry is observed and red blood cell aggregation has a notable effect on the observed trends. The two branches of the first bifurcation show similar characteristics in terms of the shapes of the profiles and the extent of plasma skimming, despite the difference in geometric configuration. In the second bifurcation, considerable asymmetry between the branches in the plasma skimming relationship is observed, and elucidated by considering individual haematocrit profiles. The results of the study highlight the importance of considering local haematocrit distributions in the analysis of blood flow and could lead to more accurate computational models of blood flow in microvascular networks. The experimental approaches developed in this work provide a foundation for further examining the characteristics of microhaemodynamics. PMID:24950214

  4. Effect of Induced Pluripotent Stem Cell Technology in Blood Banking.

    PubMed

    Focosi, Daniele; Pistello, Mauro

    2016-03-01

    Population aging has imposed cost-effective alternatives to blood donations. Artificial blood is still at the preliminary stages of development, and the need for viable cells seems unsurmountable. Because large numbers of viable cells must be promptly available for clinical use, stem cell technologies, expansion, and banking represent ideal tools to ensure a regular supply. Provided key donors can be identified, induced pluripotent stem cell (iPSC) technology could pave the way to a new era in transfusion medicine, just as it is already doing in many other fields of medicine. The present review summarizes the current state of research on iPSC technology in the field of blood banking, highlighting hurdles, and promises. ©AlphaMed Press.

  5. Hypoalbuminemia causes high blood viscosity by increasing red cell lysophosphatidylcholine.

    PubMed

    Joles, J A; Willekes-Koolschijn, N; Koomans, H A

    1997-09-01

    Albumin deficiency is accompanied by a reduction in red cell deformability and blood hyperviscosity. Albumin deficiency increases plasma fibrinogen and triglyceride levels and may alter red cell membrane lipid composition. These options, which could all contribute to reduced red cell deformability (RCD) and hyperviscosity, were studied in the Nagase analbuminemic rat (NAR), a mutant Sprague Dawley rat (CON), characterized by normal total protein levels, with an absolute deficiency of albumin, but elevated levels of non-albumin proteins and hyperlipidemia. Plasma protein-binding of the polar phopholipid lysophosphatidylcholine (LPC) was markedly decreased. LPC comprised only 26 +/- 1% of total plasma phospholipids as compared to 42 +/- 2% in CON. NAR red cells in CON plasma had a viscosity that was similar to CON red cells in CON plasma. Conversely, CON red cells in NAR plasma show an increased viscosity as compared to CON red cells in CON plasma. The maximum deformation index of both NAR and CON red cells was markedly decreased in NAR plasma as compared to either NAR or CON cells in CON plasma (0.04 +/- 0.03 and 0.02 +/- 0.02 vs. 0.22 +/- 0.06 and 0.15 +/- 0.04, respectively; P < 0.05). Thus, plasma composition causes hyperviscosity and reduced RCD in NAR. Fibrinogen is not responsible since red cells in serum and red cells in plasma had a similar viscosity and differences in viscosity and RCD between NAR and CON were maintained. Plasma triglycerides are also not responsible since the viscosity of red cells in serum with a 50% reduction in triglycerides was not reduced. LPC levels in red cells were increased in NAR (8.7 +/- 0.2 vs. 5.5 +/- 0.3% of total phospholipids; P < 0.01). Adding albumin to NAR blood dose-dependently decreased whole blood viscosity, despite marked increases in plasma viscosity, and increased RCD of NAR cells (from 0.04 +/- 0.03 to 0.21 +/- 0.01; P < 0.05). There was also some effect on CON RCD of similar albumin addition to CON blood (from 0

  6. Storage of red blood cells in a novel polyolefin blood container: a pilot in vitro study.

    PubMed

    Gulliksson, H; Meinke, S; Ravizza, A; Larsson, L; Höglund, P

    2017-01-01

    The present general plasticizer di-2-ethylhexyl-phthalate in polyvinylchloride (PVC) blood bags is only physically dispersed in PVC and will therefore leach into blood components. The objective of this study was to perform a first preliminary red blood cell (RBC) storage evaluation in a new blood bag manufactured of polyolefin without any inclusion of potentially migrating substances. This is a RBC storage study for 42 days. Blood collection was performed in a polyolefin-based PVC-free blood bag. RBCs were prepared within 8 h. Two different RBC additive solutions were used, either PAGGS-M or PAGGG-M. We weekly measured pH, K(+) , glucose, lactate, haemolysis, red cell ATP and 2,3-DPG. RBC storage in PAGGS-M resulted in high haemolysis levels already after 21 days, exceeding the European maximum limit of 0·8%, and low ATP levels by the end of the storage period. With PAGGG-M, haemolysis exceeded 0·8% after 28 days of storage. For additional parameters, the results were comparable to those of previous studies in conventional blood bags. This is a first preliminary study of RBC storage in a new type of blood bags. PAGGG-M gave encouraging results except for its inability to prevent increased haemolysis. There will be room for further development of RBC additive solutions to address the haemolysis problems. Plasma should also be tested regarding the stability of coagulation and activation pathway variables. There may also be a potential for future use of the bag for preparation of pooled buffy-coat-derived platelets. © 2016 International Society of Blood Transfusion.

  7. A smart core-sheath nanofiber that captures and releases red blood cells from the blood

    NASA Astrophysics Data System (ADS)

    Shi, Q.; Hou, J.; Zhao, C.; Xin, Z.; Jin, J.; Li, C.; Wong, S.-C.; Yin, J.

    2016-01-01

    A smart core-sheath nanofiber for non-adherent cell capture and release is demonstrated. The nanofibers are fabricated by single-spinneret electrospinning of poly(N-isopropylacrylamide) (PNIPAAm), polycaprolactone (PCL) and nattokinase (NK) solution blends. The self-assembly of PNIPAAm and PCL blends during the electrospinning generates the core-sheath PCL/PNIPAAm nanofibers with PNIPAAm as the sheath. The PNIPAAm-based core-sheath nanofibers are switchable between hydrophobicity and hydrophilicity with temperature change and enhance stability in the blood. When the nanofibers come in contact with blood, the NK is released from the nanofibers to resist platelet adhesion on the nanofiber surface, facilitating the direct capture and isolation of red blood cells (RBCs) from the blood above phase-transition temperature of PNIPAAm. Meanwhile, the captured RBCs are readily released from the nanofibers with temperature stimuli in an undamaged manner. The release efficiency of up to 100% is obtained while maintaining cellular integrity and function. This work presents promising nanofibers to effectively capture non-adherent cells and release for subsequent molecular analysis and diagnosis of single cells.A smart core-sheath nanofiber for non-adherent cell capture and release is demonstrated. The nanofibers are fabricated by single-spinneret electrospinning of poly(N-isopropylacrylamide) (PNIPAAm), polycaprolactone (PCL) and nattokinase (NK) solution blends. The self-assembly of PNIPAAm and PCL blends during the electrospinning generates the core-sheath PCL/PNIPAAm nanofibers with PNIPAAm as the sheath. The PNIPAAm-based core-sheath nanofibers are switchable between hydrophobicity and hydrophilicity with temperature change and enhance stability in the blood. When the nanofibers come in contact with blood, the NK is released from the nanofibers to resist platelet adhesion on the nanofiber surface, facilitating the direct capture and isolation of red blood cells (RBCs) from

  8. Automatic recognition of five types of white blood cells in peripheral blood.

    PubMed

    Rezatofighi, Seyed Hamid; Soltanian-Zadeh, Hamid

    2011-06-01

    This paper proposes image processing algorithms to recognize five types of white blood cells in peripheral blood automatically. First, a method based on Gram-Schmidt orthogonalization is proposed along with a snake algorithm to segment nucleus and cytoplasm of the cells. Then, a variety of features are extracted from the segmented regions. Next, most discriminative features are selected using a Sequential Forward Selection (SFS) algorithm and performances of two classifiers, Artificial Neural Network (ANN) and Support Vector Machine (SVM), are compared. The results demonstrate that the proposed methods are accurate and sufficiently fast to be used in hematological laboratories.

  9. Mobilization and harvesting of peripheral blood stem cells.

    PubMed

    Moog, Rainer

    2006-05-01

    The use of peripheral blood stem cells (PBSC) as a source of hematopoietic stem cells is steadily increasing and has nearly supplanted bone marrow. The present article reviews mobilization and collection of PBSC as well as its side effects. Specialized harvesting strategies such as large volume leukapheresis (LVL) and pediatric PBSC collection are included in this overview. Under steady state conditions, less than 0.05% of the white blood cells (WBC) are CD34+ cells. Chemotherapy results in a 5-15-fold increase of PBSC. Combining chemotherapy and growth factors increases CD34+ cells up to 6% of WBC. In the allogeneic setting, granulocyte-colony stimulating factor is used alone for PBSC mobilization. Several factors affect the mobilization of PBSC: age, gender, type of growth factor, dose of the growth factor and in the autologous setting, patient's diagnosis, chemotherapy regimen and number of previous chemotherapy cycles or radiation. Harvesting of PBSC can be performed with various blood cell separators using continuous or discontinuous flow technique. Continuous flow separators allow the processing of more blood compared with intermittent flow devices resulting in higher yields of CD34+ cells for transplantation. LVL can be used to increase the CD34+ yield in patients with low CD34+ pre-counts. Processing of more blood in LVL is achieved by an increase of the blood flow rate and an altered anticoagulation regimen. Specialized strategies were developed for pediatric PBSC collection considering the main limiting factors, extracorporeal volume and vascular access. Adverse events in PBSC collection can be subdivided in apheresis associated and mobilization associated side effects. Citrate reactions due to hypocalcemia are frequent during apheresis, especially in pediatric PBSC collection and LVL. Thrombocytopenia is often observed in patients after termination of apheresis due to platelet loss during PBSC harvesting. Muscle and bone pain are frequent adverse events

  10. Filtration parameters influencing circulating tumor cell enrichment from whole blood.

    PubMed

    Coumans, Frank A W; van Dalum, Guus; Beck, Markus; Terstappen, Leon W M M

    2013-01-01

    Filtration can achieve circulating tumor cell (CTC) enrichment from blood. Key parameters such as flow-rate, applied pressure, and fixation, vary largely between assays and their influence is not well understood. Here, we used a filtration system, to monitor these parameters and determine their relationships. Whole blood, or its components, with and without spiked tumor cells were filtered through track-etched filters. We characterize cells passing through filter pores by their apparent viscosity; the viscosity of a fluid that would pass with the same flow. We measured a ratio of 5·10(4)∶10(2)∶1 for the apparent viscosities of 15 µm diameter MDA-231 cells, 10 µm white cells and 90 fl red cells passing through a 5 µm pore. Fixation increases the pressure needed to pass cells through 8 µm pores 25-fold and halves the recovery of spiked tumor cells. Filtration should be performed on unfixed samples at a pressure of ∼10 mbar for a 1 cm(2) track-etched filter with 5 µm pores. At this pressure MDA-231 cells move through the filter in 1 hour. If fixation is needed for sample preservation, a gentle fixative should be selected. The difference in apparent viscosity between CTC and blood cells is key in optimizing recovery of CTC.

  11. Filtration Parameters Influencing Circulating Tumor Cell Enrichment from Whole Blood

    PubMed Central

    Beck, Markus; Terstappen, Leon W. M. M.

    2013-01-01

    Filtration can achieve circulating tumor cell (CTC) enrichment from blood. Key parameters such as flow-rate, applied pressure, and fixation, vary largely between assays and their influence is not well understood. Here, we used a filtration system, to monitor these parameters and determine their relationships. Whole blood, or its components, with and without spiked tumor cells were filtered through track-etched filters. We characterize cells passing through filter pores by their apparent viscosity; the viscosity of a fluid that would pass with the same flow. We measured a ratio of 5·104∶102∶1 for the apparent viscosities of 15 µm diameter MDA-231 cells, 10 µm white cells and 90 fl red cells passing through a 5 µm pore. Fixation increases the pressure needed to pass cells through 8 µm pores 25-fold and halves the recovery of spiked tumor cells. Filtration should be performed on unfixed samples at a pressure of ∼10 mbar for a 1 cm2 track-etched filter with 5 µm pores. At this pressure MDA-231 cells move through the filter in 1 hour. If fixation is needed for sample preservation, a gentle fixative should be selected. The difference in apparent viscosity between CTC and blood cells is key in optimizing recovery of CTC. PMID:23658615

  12. THE AGGLUTINATION OF RED BLOOD CELLS

    PubMed Central

    Northrop, John H.; Freund, Jules

    1924-01-01

    1. Unsensitized sheep cells suspended in sugar solutions are agglutinated by electrolytes whenever the potential is depressed to 6 millivolts or less, except in the case of MgCl2 or CaCl2. 2. With these salts no agglutination occurs although there is practically no potential. The presence of these salts prevents acid agglutination. This is presumably due to a decrease in the "cohesion" between the cells. 3. Cells which have been sensitized with specific antibody, ricin, colloidal stannic hydroxide, or paraffin oil, are agglutinated whenever the potential is decreased below about 12 millivolts. 4. The agglutination by electrolytes is therefore primarily due to a decrease in the potential whereas agglutination by immune serum, ricin, etc., is due primarily to an increase in the critical potential. PMID:19872099

  13. Viable Bacteria Associated with Red Blood Cells and Plasma in Freshly Drawn Blood Donations

    PubMed Central

    Damgaard, Christian; Magnussen, Karin; Enevold, Christian; Nilsson, Martin; Tolker-Nielsen, Tim; Holmstrup, Palle; Nielsen, Claus Henrik

    2015-01-01

    Objectives Infection remains a leading cause of post-transfusion mortality and morbidity. Bacterial contamination is, however, detected in less than 0.1% of blood units tested. The aim of the study was to identify viable bacteria in standard blood-pack units, with particular focus on bacteria from the oral cavity, and to determine the distribution of bacteria revealed in plasma and in the red blood cell (RBC)-fraction. Design Cross-sectional study. Blood were separated into plasma and RBC-suspensions, which were incubated anaerobically or aerobically for 7 days on trypticase soy blood agar (TSA) or blue lactose plates. For identification colony PCR was performed using primers targeting 16S rDNA. Setting Blood donors attending Capital Region Blood Bank, Copenhagen University Hospital, Rigshospitalet, Hvidovre, Denmark, October 29th to December 10th 2013. Participants 60 donors (≥50 years old), self-reported medically healthy. Results Bacterial growth was observed on plates inoculated with plasma or RBCs from 62% of the blood donations. Growth was evident in 21 (35%) of 60 RBC-fractions and in 32 (53%) of 60 plasma-fractions versus 8 of 60 negative controls (p = 0.005 and p = 2.6x10-6, respectively). Propionibacterium acnes was found in 23% of the donations, and Staphylococcus epidermidis in 38%. The majority of bacteria identified in the present study were either facultative anaerobic (59.5%) or anaerobic (27.8%) species, which are not likely to be detected during current routine screening. Conclusions Viable bacteria are present in blood from donors self-reported as medically healthy, indicating that conventional test systems employed by blood banks insufficiently detect bacteria in plasma. Further investigation is needed to determine whether routine testing for anaerobic bacteria and testing of RBC-fractions for adherent bacteria should be recommended. PMID:25751254

  14. On-chip Extraction of Intracellular Molecules in White Blood Cells from Whole Blood

    NASA Astrophysics Data System (ADS)

    Choi, Jongchan; Hyun, Ji-Chul; Yang, Sung

    2015-10-01

    The extraction of virological markers in white blood cells (WBCs) from whole blood—without reagents, electricity, or instruments—is the most important first step for diagnostic testing of infectious diseases in resource-limited settings. Here we develop an integrated microfluidic chip that continuously separates WBCs from whole blood and mechanically ruptures them to extract intracellular proteins and nucleic acids for diagnostic purposes. The integrated chip is assembled with a device that separates WBCs by using differences in blood cell size and a mechanical cell lysis chip with ultra-sharp nanoblade arrays. We demonstrate the performance of the integrated device by quantitatively analyzing the levels of extracted intracellular proteins and genomic DNAs. Our results show that compared with a conventional method, the device yields 120% higher level of total protein amount and similar levels of gDNA (90.3%). To demonstrate its clinical application to human immunodeficiency virus (HIV) diagnostics, the developed chip was used to process blood samples containing HIV-infected cells. Based on PCR results, we demonstrate that the chip can extract HIV proviral DNAs from infected cells with a population as low as 102/μl. These findings suggest that the developed device has potential application in point-of-care testing for infectious diseases in developing countries.

  15. On-chip Extraction of Intracellular Molecules in White Blood Cells from Whole Blood

    PubMed Central

    Choi, Jongchan; Hyun, Ji-chul; Yang, Sung

    2015-01-01

    The extraction of virological markers in white blood cells (WBCs) from whole blood—without reagents, electricity, or instruments—is the most important first step for diagnostic testing of infectious diseases in resource-limited settings. Here we develop an integrated microfluidic chip that continuously separates WBCs from whole blood and mechanically ruptures them to extract intracellular proteins and nucleic acids for diagnostic purposes. The integrated chip is assembled with a device that separates WBCs by using differences in blood cell size and a mechanical cell lysis chip with ultra-sharp nanoblade arrays. We demonstrate the performance of the integrated device by quantitatively analyzing the levels of extracted intracellular proteins and genomic DNAs. Our results show that compared with a conventional method, the device yields 120% higher level of total protein amount and similar levels of gDNA (90.3%). To demonstrate its clinical application to human immunodeficiency virus (HIV) diagnostics, the developed chip was used to process blood samples containing HIV-infected cells. Based on PCR results, we demonstrate that the chip can extract HIV proviral DNAs from infected cells with a population as low as 102/μl. These findings suggest that the developed device has potential application in point-of-care testing for infectious diseases in developing countries. PMID:26464211

  16. Twenty-five years of peripheral blood stem cell transplantation.

    PubMed

    Körbling, Martin; Freireich, Emil J

    2011-06-16

    Peripheral blood stem cell transplantation (PBSCT) is the most common transplantation procedure performed in medicine. Its clinical introduction in 1986 replaced BM as a stem-cell source to approximately 100% in the autologous and to approximately 75% in the allogeneic transplantation setting. This historical overview provides a brief insight into the discovery of circulating hematopoietic stem cells in the early 1960s, the development of apheresis technology, the discovery of hematopoietic growth factors and small molecule CXCR4 antagonist for stem- cell mobilization, and in vivo experimental transplantation studies that eventually led to clinical PBSCT. Also mentioned are the controversies surrounding the engraftment potential of circulating stem cells before acceptance as a clinical modality. Clinical trials comparing the outcome of PBSCT with BM transplantation, registry data analyses, and the role of the National Marrow Donor Program (NMDP) in promoting unrelated blood stem-cell donation are addressed.

  17. Nanoscale dielectrophoretic spectroscopy of individual immobilized mammalian blood cells.

    PubMed

    Lynch, Brian P; Hilton, Al M; Simpson, Garth J

    2006-10-01

    Dielectrophoretic force microscopy (DEPFM) and spectroscopy have been performed on individual intact surface-immobilized mammalian red blood cells. Dielectrophoretic force spectra were obtained in situ in approximately 125 ms and could be acquired over a region comparable in dimension to the effective diameter of a scanning probe microscopy tip. Good agreement was observed between the measured dielectrophoretic spectra and predictions using a single-shell cell model. In addition to allowing for highly localized dielectric characterization, DEPFM provided a simple means for noncontact imaging of mammalian blood cells under aqueous conditions. These studies demonstrate the feasibility of using DEPFM to monitor localized changes in membrane capacitance in real time with high spatial resolution on immobilized cells, complementing previous studies of mobile whole cells and cell suspensions.

  18. Combined cell index in assessing blood donor iron stores.

    PubMed

    Vuk, T; Bingulac-Popović, J; Očić, T; Mayer, L J; Milošević, M; Jukić, I

    2017-02-01

    The aim of this study was to assess the appropriateness of using combined cell index (CCI) in the assessment of iron stores in blood donors. This index is calculated by the formula: red blood cell distribution width (RDW) × 10(4) × mean corpuscular volume (MCV)(-1) × mean corpuscular haemoglobin (MCH)(-1) . Ferritin measurement is a reliable method for estimating iron stores in blood donors. The sensitivity of red blood cell (RBC) parameters of complete blood count in detecting non-anaemic iron deficiency is significantly lower. Consequently, there were several attempts to increase the detection sensitivity by combining these parameters in different indices. This study included 1084 male and 792 female whole blood donors accepted for blood donation. For six RBC parameters with the highest level of correlation relative to ferritin [Hgb, MCV, MCH, mean corpuscular haemoglobin concentration (MCHC), RDW and CCI], diagnostic efficacy in the detection of iron depletion (ferritin <12 µg L(-1) ) was assessed using receiver operating characteristic (ROC) analysis. CCI showed the highest degree of correlation with ferritin (r = -0·373 for men and r = -0·590 for women) and the highest area under the curve (0·961 for men and 0·864 for women). Using the cut-off value of 52·6 for men and 50·6 for women, the corresponding Youden index was the highest for CCI in both genders (0·851 for men and 0·612 for women). The sensitivity and specificity of CCI in the population of male donors were higher in comparison to female donors (0·941 and 0·910 vs 0·851 and 0·761, respectively). Study results confirmed the satisfactory diagnostic value of CCI in detecting depleted iron stores in blood donors. © 2016 British Blood Transfusion Society.

  19. Erythropoietin reduces storage lesions and decreases apoptosis indices in blood bank red blood cells.

    PubMed

    Penuela, Oscar Andrés; Palomino, Fernando; Gómez, Lina Andrea

    2016-01-01

    Recent evidence shows a selective destruction of the youngest circulating red blood cells (neocytolysis) trigged by a drop in erythropoietin levels. The aim of this study was to evaluate the effect of recombinant human erythropoietin beta on the red blood cell storage lesion and apoptosis indices under blood bank conditions. Each one of ten red blood cell units preserved in additive solution 5 was divided in two volumes of 100mL and assigned to one of two groups: erythropoietin (addition of 665IU of recombinant human erythropoietin) and control (isotonic buffer solution was added). The pharmacokinetic parameters of erythropoietin were estimated and the following parameters were measured weekly, for six weeks: Immunoreactive erythropoietin, hemolysis, percentage of non-discocytes, adenosine triphosphate, glucose, lactate, lactate dehydrogenase, and annexin-V/esterase activity. The t-test or Wilcoxon's test was used for statistical analysis with significance being set for a p-value <0.05. Erythropoietin, when added to red blood cell units, has a half-life >6 weeks under blood bank conditions, with persistent supernatant concentrations of erythropoietin during the entire storage period. Adenosine triphosphate was higher in the Erythropoietin Group in Week 6 (4.19±0.05μmol/L vs. 3.53±0.02μmol/L; p-value=0.009). The number of viable cells in the Erythropoietin Group was higher than in the Control Group (77%±3.8% vs. 71%±2.3%; p-value <0.05), while the number of apoptotic cells was lower (9.4%±0.3% vs. 22%±0.8%; p-value <0.05). Under standard blood bank conditions, an important proportion of red blood cells satisfy the criteria of apoptosis. Recombinant human erythropoietin beta seems to improve storage lesion parameters and mitigate apoptosis. Copyright © 2015 Associação Brasileira de Hematologia, Hemoterapia e Terapia Celular. Published by Elsevier Editora Ltda. All rights reserved.

  20. Erythropoietin reduces storage lesions and decreases apoptosis indices in blood bank red blood cells

    PubMed Central

    Penuela, Oscar Andrés; Palomino, Fernando; Gómez, Lina Andrea

    2015-01-01

    Background Recent evidence shows a selective destruction of the youngest circulating red blood cells (neocytolysis) trigged by a drop in erythropoietin levels. Objective The aim of this study was to evaluate the effect of recombinant human erythropoietin beta on the red blood cell storage lesion and apoptosis indices under blood bank conditions. Methods Each one of ten red blood cell units preserved in additive solution 5 was divided in two volumes of 100 mL and assigned to one of two groups: erythropoietin (addition of 665 IU of recombinant human erythropoietin) and control (isotonic buffer solution was added). The pharmacokinetic parameters of erythropoietin were estimated and the following parameters were measured weekly, for six weeks: Immunoreactive erythropoietin, hemolysis, percentage of non-discocytes, adenosine triphosphate, glucose, lactate, lactate dehydrogenase, and annexin-V/esterase activity. The t-test or Wilcoxon's test was used for statistical analysis with significance being set for a p-value <0.05. Results Erythropoietin, when added to red blood cell units, has a half-life >6 weeks under blood bank conditions, with persistent supernatant concentrations of erythropoietin during the entire storage period. Adenosine triphosphate was higher in the Erythropoietin Group in Week 6 (4.19 ± 0.05 μmol/L vs. 3.53 ± 0.02 μmol/L; p-value = 0.009). The number of viable cells in the Erythropoietin Group was higher than in the Control Group (77% ± 3.8% vs. 71% ± 2.3%; p-value <0.05), while the number of apoptotic cells was lower (9.4% ± 0.3% vs. 22% ± 0.8%; p-value <0.05). Conclusions Under standard blood bank conditions, an important proportion of red blood cells satisfy the criteria of apoptosis. Recombinant human erythropoietin beta seems to improve storage lesion parameters and mitigate apoptosis. PMID:26969770

  1. [Immunophenotypic characteristics of peripheral blood cells in normal elderly men].

    PubMed

    Wang, Ya-Zhe; Chang, Yan; Lu, Dan; Shi, Hong-Xia; Huang, Xiao-Jun; Liu, Yan-Rong

    2013-12-01

    This study was aimed to distinguish abnormal cells and to diagnose hematologic diseases through recognizing antigen expression pattern and percentage of peripheral blood cells in normal elderly men. Antigen expression of blast cells, granulocytes, monocytes, lymphocytes, nucleated red blood cells and plasma cells was detected by seven-color flow cytometry in a total of 88 peripheral blood samples from normal elderly men, aged median 82 years old, from 70 to 98 years. Groups were divided according to age, region and underlying diseases, and the percentages of different subgroup cells were examined to confirm whether the differences were significant or not. The results showed that the median proportion of CD34(+) blast cells in peripheral blood from normal elderly men were 0.017% (0.015%-0.020%), with high expression of HLA-DR, CD33, CD13 and CD117, low expression of myeloid antigens, such as CD15, CD11b and CD16, while lymphoid antigens were seldom positive, including CD7, CD19 and CD56. Dim-expression of CD38 was found in peripheral blood blast cells, CD38(dim)+/- cell percentage in blast cells was 61.36% ± 18.26%. In the differentiation and development of granulocytes, CD16(-), CD13(+) CD16(+) (intermediate) and CD16(+) (strong) CD13(+) cells appeared in sequence from immature to mature granulocytes, whose median proportions in nuclear cells were 0.04%, 0.30% and 61.30%, respectively. The percentages of immature monocytes, such as CD64(+) CD14(-) and HLA-DR(+) CD11b(-) cells, were from 0.00% to 0.10% and from 0.07% to 0.68%, separately. No significant differences were found between different subgroups (P > 0.05). It is concluded that the immunophenotypic characteristics and referential percentages of CD34(+) blast cells, granulocytes and monocytes with different development stages in peripheral blood from normal elderly men are recognized, which can help to discriminate abnormal cells.

  2. Induction of platelet white blood cell (WBC) aggregate formation by platelets and WBCs in red blood cell units.

    PubMed

    Keating, Friederike K; Fung, Mark K; Schneider, David J

    2008-06-01

    Transfusion of red blood cell (RBC) preparations is independently associated with adverse clinical outcomes in patients with acute cardiovascular disease. This study was designed to define mechanisms potentially contributing. The presence of platelets (PLTs), activated PLTs (PLTs expressing P-selectin), PLT-monocyte aggregates (PMAs), and PLT-neutrophil aggregates (PNAs) was determined in vitro with the use of flow cytometry in whole blood from healthy volunteers, in RBCs, and in whole blood after adding aliquots of RBCs. Both prestorage leukoreduced and nonleukoreduced RBCs were analyzed. Nonleukoreduced RBCs were subfractionated with the use of centrifugation and filtration to obtain a RBC-free and a cell-free fraction. Formation of PMAs and PNAs was determined in whole blood after the addition of aliquots of these subfractions. Nonleukoreduced RBCs contained 50 +/- 18 percent of the PLTs found in whole blood from healthy volunteers, and 43 +/- 16 percent of the PLTs were activated. Leukoreduced RBCs contained few PLTs (0.2 +/- 0.1% of volunteer blood). The majority (>60%) of white blood cells (WBCs) in nonleukoreduced RBCs were associated with PLTs. The formation of PMAs and PNAs in whole blood was increased approximately fivefold after addition of nonleukoreduced-RBCs (p < 0.0001) and by less than twofold with leukoreduced RBCs (p = 0.01). Addition of the essentially cell-free fraction of nonleukoreduced RBCs did not increase the formation of PNA or PMA in whole blood significantly. RBC preparations, particularly nonleukoreduced RBCs, contain activated PLTs and PLT-WBC aggregates and induce formation of PLT-WBC aggregates. This may be one mechanism contributing to adverse outcomes linked to transfusions in patients with cardiovascular disease.

  3. Peripheral markers of Alzheimer's disease: surveillance of white blood cells.

    PubMed

    Shad, Kaneez Fatima; Aghazadeh, Yashar; Ahmad, Sagheer; Kress, Bodo

    2013-08-01

    Inflammation is part of the complex biological response of vascular tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. This is a mechanism of innate immunity, which may cause an increase in the number of monocytes and neutrophils circulating in the blood. Literature indicated that chronic inflammation might be a factor in developing neurological problems, including Alzheimer's, Parkinson's and other similar illnesses. Our main objective is to identify peripheral markers of Alzheimer's disease and for that purpose; we are looking at the profile of white blood cells focusing on monocytes, neutrophils, lymphocytes and basophils. Twenty-seven patients of Alzheimer's disease (AD), diagnosed by magnetic resonance imaging and neuropsychological tests were observed for their blood profile. Key observations during this study were that the levels of monocytes in the blood of the diagnosed AD patients were high irrespective of their age and sex. For those patients whose monocytes were in normal range their neutrophil levels were significantly high. Whereas blood levels of lymphocytes and basophils were found to be constantly low. Escalated levels of monocytes and neutrophils are hallmarks of chronic inflammation and may be precursor to Alzheimer's disease. A low lymphocyte count specifies that the body's resistance to fight infection is substantially reduced, whereas low basophil levels indicates their over utilization due to chronic allergic inflammatory condition. Future studies involved closer look at the cytokines produced by these white blood cells especially TNF IL-1, and IL-12, which are products of monocytes. Likewise, blood glucose and creatinine levels were high whereas calcium ions were low. Our studies indicated that white blood cells along with other inflammatory byproducts may act as peripheral markers for early diagnosis of Alzheimer's disease.

  4. Method and kit for the selective labeling of red blood cells in whole blood with Tc-99m

    DOEpatents

    Srivastava, S.C.; Babich, J.W.; Straub, R.; Richards, P.

    1988-07-05

    Disclosed herein are a method and kit for the preparation of [sup 99m]Tc labeled red blood cells using whole blood in a closed sterile system containing stannous tin in a form such that it will enter the red blood cells and be available for the reduction of technetium. No Drawings

  5. Method and kit for the selective labeling of red blood cells in whole blood with TC-99M

    DOEpatents

    Srivastava, Suresh C.; Babich, John W.; Straub, Rita; Richards, Powell

    1988-01-01

    Disclosed herein are a method and kit for the preparation of .sup.99m Tc labeled red blood cells using whole blood in a closed sterile system containing stannous tin in a form such that it will enter the red blood cells and be available therein for the reduction of technetium.

  6. Histochemistry of blood and bone marrow cells in pangolins.

    PubMed Central

    Caxton-Martins, A E

    1977-01-01

    Blood and bone marrow cells of pangolins have been examined histochemically. Sudanophilia, PAS positivity and acid phosphatase and alkaline phosphatase reactivity were confined to cells of the granulocytic and monocytic series, while peroxidase reactivity was confined to cells of the erythroid series. In this latter respect the pangolin is unique among mammals so far studied. Images Figs. 1, 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Figs. 7, 8 Fig. 9 Fig. 10 PMID:858692

  7. Red blood cells radial dispersion in blood flowing through microchannels: The role of temperature.

    PubMed

    Pinho, Diana; Rodrigues, Raquel O; Faustino, Vera; Yaginuma, Tomoko; Exposto, José; Lima, Rui

    2016-07-26

    The behavior of suspensions of individual blood cells, such as red blood cells (RBCs), flowing through microvessels and microfluidic systems depend strongly on the hematocrit (Hct), microvessel topology and cell properties. Although it is well known that blood rheological properties are temperature dependent, to the best of our knowledge no work has studied the role of the temperature on the RBCs dispersion. A powerful way to investigate this latter effect is through a high-speed video microscopy system, which provides detailed flow measurements of each individual RBC. Hence, the effect of temperature on the RBCs dispersion flowing through a 100μm glass capillary was examined by means of a confocal micro-PTV system. Hundreds of labeled RBCs were tracked at moderate Hct (12%) and at four different temperatures, i.e., 25°C, 32°C, 37°C and 42°C. The results yielded an enhancement of the RBCs diffusion as the temperature increases. Hence, our findings show that RBCs radial dispersion is temperature dependent and as a result the temperature should not be ignored in future blood flow studies. We believe that this finding is important for a better understanding of blood mass transport mechanisms under both physiological and pathological conditions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Polyphenols enhance total oxidant-scavenging capacities of human blood by binding to red blood cells.

    PubMed

    Koren, Erez; Kohen, Ron; Ginsburg, Isaac

    2010-06-01

    The present study offers a new look at the role of erythrocytes and of erythrocytes-polyphenol complexes as potent 'sinks' for reactive oxygen species. We hereby show that human erythrocytes have the capacity not only to carry oxygen, but also to bind avidly to their surfaces a large variety of polyphenol antioxidants, which endows upon such complexes enhanced total oxidant-scavenging capacities (TOSC). This was proven by using confocal microscopy, 2,2-diphenyl-1-picrylhydrazyl radical, Folin-Ciocalteu's reagent, cyclic voltammetry and chemiluminescence techniques. The results presented suggest that the true TOSC of blood is the sum of intracellular antioxidants of red blood cells and other blood cells (mainly due to catalase), the polyphenols bound to their surfaces and the antioxidant agents present in plasma. Since erythrocytes can avidly bind and rapidly remove circulating polyphenols, the rule of the thumb to quantify antioxidants in health and disease processes exclusively in plasma as customary in clinical settings, does not represent the true TOSC of whole blood. We also postulate that circulating erythrocytes and possibly also other blood cells might be constantly coated by polyphenols from supplemented nutrients, which act as antioxidant depots and can thus act as protectors against the harmful consequences of oxidative stress. Further studies are needed to determine the faith of polyphenols in the circulation and their sequestration in the spleen.

  9. Cytomegalovirus in Australian blood donors: seroepidemiology and seronegative red blood cell component inventories.

    PubMed

    Lancini, Daniel V; Faddy, Helen M; Ismay, Sue; Chesneau, Stuart; Hogan, Chris; Flower, Robert L

    2016-06-01

    Cytomegalovirus (CMV) can lead to severe disease in high-risk subpopulations. To prevent transfusion-transmitted CMV in these patient groups, the Australian Red Cross Blood Service maintains inventories of CMV-seronegative fresh blood components. Donor demographic data and CMV seroscreening results for all blood donations and blood components issued in Australia between financial years (FYs) 2008/09 to 2012/13 inclusive were obtained. Population estimates were also extracted for the calculation of age-weighted seroprevalence estimates. Linear regression was used to model trends in red blood cell (RBC) component acquisition and demand. The estimated age-weighted seroprevalence of CMV in 20- to 69-year old Australians was 76.12 ± 0.13%, with higher seroprevalence in females and older age groups. Seroprevalence decreased over the study period, while the demand for CMV-seronegative RBC components increased. It was predicted that component acquisition may be insufficient by FY 2017/18 if current trends persist. These findings represent an evaluation of CMV seroepidemiology in Australia and form a basis to predict the future status of CMV-seronegative RBC component inventories. The results will serve to guide Blood Service operations and inform current international debate on CMV-safe blood components. © 2016 AABB.

  10. Blood Cell Separation Device Using Serially Connected Membrane Filters for Adapting to Blood Flow Properties

    NASA Astrophysics Data System (ADS)

    Kobayashi, Taizo; Kato, Daiki; Koga, Hiroyuki; Morimoto, Kenichi; Fukuda, Makoto; Kinoshita, Yoshiharu; Yoshida, Hiroshi; Konishi, Satoshi

    This paper proposes a cooperative operation of serially connected membrane filters toward adaptive blood cell separation system in order to overcome a restriction of a single membrane filter. Serially connected membrane filters allow that downstream filters extract blood plasma from residual blood at upstream filters. Consequently, it becomes possible to adapt filtering characteristics to changing properties of blood. We focus on trans-membrane pressure difference in order to prevent hemolysis. Our strategy can be realized as a miniaturized PDMS fluidic chip. Our laboratory experiment using a prototype shows that plasma extraction efficiency is improved from 34% to 75%. Toward an integrated system, this paper also demonstrates multiple filters are successfully integrated into a PDMS fluidic chip.

  11. Toward Rare Blood Cell Preservation for RNA Sequencing.

    PubMed

    Vickovic, Sanja; Ahmadian, Afshin; Lewensohn, Rolf; Lundeberg, Joakim

    2015-07-01

    Cancer is driven by various events leading to cell differentiation and disease progression. Molecular tools are powerful approaches for describing how and why these events occur. With the growing field of next-generation DNA sequencing, there is an increasing need for high-quality nucleic acids derived from human cells and tissues-a prerequisite for successful cell profiling. Although advances in RNA preservation have been made, some of the largest biobanks still do not employ RNA blood preservation as standard because of limitations in low blood-input volume and RNA stability over the whole gene body. Therefore, we have developed a robust protocol for blood preservation and long-term storage while maintaining RNA integrity. Furthermore, we explored the possibility of using the protocol for preserving rare cell samples, such as circulating tumor cells. The results of our study confirmed that gene expression was not impacted by the preservation procedure (r(2) > 0.88) or by long-term storage (r(2) = 0.95), with RNA integrity number values averaging over 8. Similarly, cell surface antigens were still available for antibody selection (r(2) = 0.95). Lastly, data mining for fusion events showed that it was possible to detect rare tumor cells among a background of other cells present in blood irrespective of fixation. Thus, the developed protocol would be suitable for rare blood cell preservation followed by RNA sequencing analysis. Copyright © 2015 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

  12. In vivo red blood cell compatibility testing using indium-113m tropolone-labeled red blood cells

    SciTech Connect

    Morrissey, G.J.; Gravelle, D.; Dietz, G.; Driedger, A.A.; King, M.; Cradduck, T.D.

    1988-05-01

    In vivo radionuclide crossmatch is a method for identifying compatible blood for transfusion when allo- or autoantibodies preclude the use of conventional crossmatching techniques. A technique for labeling small volumes of donor red blood cells with (/sup 113m/In)tropolone is reported. The use of /sup 113m/In minimizes the accumulation of background radioactivity and the radiation dose especially so when multiple crossmatches are performed. Labeling red cells with (/sup 113m/In)tropolone is faster and easier to perform than with other radionuclides. Consistently high labeling efficiencies are obtained and minimal /sup 113m/In activity elutes from the labeled red blood cells. A case study involving 22 crossmatches is presented to demonstrate the technique. The radiation dose equivalent from /sup 113m/In is significantly less than with other radionuclides that may be used to label red cells.

  13. Patient-specific blood rheology in sickle-cell anaemia.

    PubMed

    Li, Xuejin; Du, E; Lei, Huan; Tang, Yu-Hang; Dao, Ming; Suresh, Subra; Karniadakis, George Em

    2016-02-06

    Sickle-cell anaemia (SCA) is an inherited blood disorder exhibiting heterogeneous cell morphology and abnormal rheology, especially under hypoxic conditions. By using a multiscale red blood cell (RBC) model with parameters derived from patient-specific data, we present a mesoscopic computational study of the haemodynamic and rheological characteristics of blood from SCA patients with hydroxyurea (HU) treatment (on-HU) and those without HU treatment (off-HU). We determine the shear viscosity of blood in health as well as in different states of disease. Our results suggest that treatment with HU improves or worsens the rheological characteristics of blood in SCA depending on the degree of hypoxia. However, on-HU groups always have higher levels of haematocrit-to-viscosity ratio (HVR) than off-HU groups, indicating that HU can indeed improve the oxygen transport potential of blood. Our patient-specific computational simulations suggest that the HVR level, rather than the shear viscosity of sickle RBC suspensions, may be a more reliable indicator in assessing the response to HU treatment.

  14. Measuring osmosis and hemolysis of red blood cells.

    PubMed

    Goodhead, Lauren K; MacMillan, Frances M

    2017-06-01

    Since the discovery of the composition and structure of the mammalian cell membrane, biologists have had a clearer understanding of how substances enter and exit the cell's interior. The selectively permeable nature of the cell membrane allows the movement of some solutes and prevents the movement of others. This has important consequences for cell volume and the integrity of the cell and, as a result, is of utmost clinical importance, for example in the administration of isotonic intravenous infusions. The concepts of osmolarity and tonicity are often confused by students as impermeant isosmotic solutes such as NaCl are also isotonic; however, isosmotic solutes such as urea are actually hypotonic due to the permeant nature of the membrane. By placing red blood cells in solutions of differing osmolarities and tonicities, this experiment demonstrates the effects of osmosis and the resultant changes in cell volume. Using hemoglobin standard solutions, where known concentrations of hemoglobin are produced, the proportion of hemolysis and the effect of this on resultant hematocrit can be estimated. No change in cell volume occurs in isotonic NaCl, and, by placing blood cells in hypotonic NaCl, incomplete hemolysis occurs. By changing the bathing solution to either distilled water or isosmotic urea, complete hemolysis occurs due to their hypotonic effects. With the use of animal blood in this practical, students gain useful experience in handling tissue fluids and calculating dilutions and can appreciate the science behind clinical scenarios. Copyright © 2017 the American Physiological Society.

  15. Distinct Regulatory Effects of Myeloid Cell and Endothelial Cell NAPDH Oxidase 2 on Blood Pressure.

    PubMed

    Sag, Can Martin; Schnelle, Moritz; Zhang, Juqian; Murdoch, Colin E; Kossmann, Sabine; Protti, Andrea; Santos, Celio X C; Sawyer, Greta; Zhang, Xiaohong; Mongue-Din, Heloise; Richards, Daniel A; Brewer, Alison C; Prysyazhna, Oleksandra; Maier, Lars S; Wenzel, Philip; Eaton, Philip J; Shah, Ajay M

    2017-05-30

    Hypertension caused by increased renin-angiotensin system activation is associated with elevated reactive oxygen species production. Previous studies implicate NADPH oxidase (Nox) proteins as important reactive oxygen species sources during renin-angiotensin system activation, with different Nox isoforms being potentially involved. Among these, Nox2 is expressed in multiple cell types, including endothelial cells, fibroblasts, immune cells, and microglia. Blood pressure (BP) is regulated at the central nervous system, renal, and vascular levels, but the cell-specific role of Nox2 in BP regulation is unknown. We generated a novel mouse model with a floxed Nox2 gene and used Tie2-Cre, LysM Cre, or Cdh5-CreERT2 driver lines to develop cell-specific models of Nox2 perturbation to investigate its role in BP regulation. Unexpectedly, Nox2 deletion in myeloid but not endothelial cells resulted in a significant reduction in basal BP. Both Tie2-CreNox2 knockout (KO) mice (in which Nox2 was deficient in both endothelial cells and myeloid cells) and LysM CreNox2KO mice (in which Nox2 was deficient in myeloid cells) had significantly lower BP than littermate controls, whereas basal BP was unaltered in Cdh5-CreERT2 Nox2KO mice (in which Nox2 is deficient only in endothelial cells). The lower BP was attributable to an increased NO bioavailability that dynamically dilated resistance vessels in vivo under basal conditions without a change in renal function. Myeloid-specific Nox2 deletion had no effect on angiotensin II-induced hypertension, which, however, was blunted in Tie2-CreNox2KO mice, along with preservation of endothelium-dependent relaxation during angiotensin II stimulation. We identify a hitherto unrecognized modulation of basal BP by myeloid cell Nox2, whereas endothelial cell Nox2 regulates angiotensin II-induced hypertension. These results identify distinct cell-specific roles for Nox2 in BP regulation. © 2017 The Authors.

  16. Stem cell terminology: practical, theological and ethical implications.

    PubMed

    Shanner, Laura

    2002-01-01

    Stem cell policy discussions frequently confuse embryonic and fetal sources of stem cells, and label untested, non-reproductive cloning as "therapeutic." Such misnomers distract attention from significant practical and ethical implications: accelerated research agendas tend to be supported at the expense of physical risks to women, theological implications in a multi-faith community, informed consent for participation in research, and treatment decisions altered by unrealistic expectations.

  17. Increased levels of (class switched) memory B cells in peripheral blood of current smokers.

    PubMed

    Brandsma, Corry-Anke; Hylkema, Machteld N; Geerlings, Marie; van Geffen, Wouter H; Postma, Dirkje S; Timens, Wim; Kerstjens, Huib A M

    2009-11-12

    There is increasing evidence that a specific immune response contributes to the pathogenesis of COPD. B-cell follicles are present in lung tissue and increased anti-elastin titers have been found in plasma of COPD patients. Additionally, regulatory T cells (Tregs) have been implicated in its pathogenesis as they control immunological reactions. We hypothesize that the specific immune response in COPD is smoke induced, either by a direct effect of smoking or as a result of smoke-induced lung tissue destruction (i.e. formation of neo-epitopes or auto antigens). Furthermore, we propose that Tregs are involved in the suppression of this smoke-induced specific immune response.The presence of B cells, memory B cells and Tregs was assessed by flow cytometry in peripheral blood of 20 COPD patients and 29 healthy individuals and related to their current smoking status.COPD patients had lower (memory) B-cell percentages and higher Treg percentages in peripheral blood than healthy individuals, with a significant negative correlation between these cells. Interestingly, current smokers had higher percentages of (class-switched) memory B cells than ex-smokers and never smokers, irrespective of COPD.This increase in (class-switched) memory B cells in current smokers is intriguing and suggests that smoke-induced neo-antigens may be constantly induced in the lung. The negative correlation between B cells and Tregs in blood is in line with previously published observations that Tregs can suppress B cells. Future studies focusing on the presence of these (class switched) memory B cells in the lung, their antigen specificity and their interaction with Tregs are necessary to further elucidate the specific B-cell response in COPD.

  18. Red blood cell-derived microparticles: An overview.

    PubMed

    Westerman, Maxwell; Porter, John B

    2016-07-01

    The red blood cell (RBC) is historically the original parent cell of microparticles (MPs). In this overview, we describe the discovery and the early history of red cell-derived microparticles (RMPs) and present an overview of the evolution of RMP. We report the formation, characteristics, effects of RMP and factors which may affect RMP evaluation. The review examines RMP derived from both normal and pathologic RBC. The pathologic RBC studies include sickle cell anemia (SCA), sickle cell trait (STr), thalassemia intermedia (TI), hereditary spherocytosis (HS), hereditary elliptocytosis (HE), hereditary stomatocytosis (HSt) and glucose-6-phosphate dehydrogenase deficiency (G6PD). Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Depletion induced clustering of red blood cells in microchannels

    NASA Astrophysics Data System (ADS)

    Wagner, Christian; Brust, Mathias; Podgorski, Thomas; Coupier, Gwennou

    2012-11-01

    The flow properties of blood are determined by the physical properties of its main constituents, the red blood cells (RBC's). At low shear rates RBC's form aggregates, so called rouleaux. Higher shear rates can break them up and the viscosity of blood shows a shear thinning behavior. The physical origin of the rouleaux formation is not yet fully resolved and there are two competing models available. One predicts that the adhesion is induced by bridging of the plasma (macromolecular) proteins in-between two RBC's. The other is based on the depletion effect and thus predicts the absence of macromolecules in-between the cells of a rouleaux. Recent single cell force measurements by use of an AFM support strongly the depletion model. By varying the concentration of Dextran at different molecular weights we can control the adhesions strength. Measurements at low hematocrit in a microfluidic channel show that the number of size of clusters is determined by the depletion induced adhesion strength.

  20. The role of blood rheology in sickle cell disease.

    PubMed

    Connes, Philippe; Alexy, Tamas; Detterich, Jon; Romana, Marc; Hardy-Dessources, Marie-Dominique; Ballas, Samir K

    2016-03-01

    Studies performed in the last decades have highlighted the need to better understand the contribution of the endothelium, vascular function, oxidative stress, inflammation, coagulation, hemolysis and vascular adhesion mechanisms to the pathophysiology of acute vaso-occlusive like events and chronic organ damages in sickle cell disease (SCD). Although SCD is a hemorheological disease, a few works focused on the contribution of blood viscosity, plasma viscosity, red blood cell deformability and aggregation in the pathophysiology of SCD. After a brief description of basic hemorheology, the present review focuses on the role of the hemorheological abnormalities in the causation of several SCD complications, mainly in sickle cell anemia and hemoglobin (Hb) SC disease. Several genetic and cellular modulators of blood rheology in SCD are discussed, as well as unresolved questions and perspectives.

  1. Apheresis techniques for collection of peripheral blood progenitor cells.

    PubMed

    Moog, Rainer

    2004-12-01

    The combination of effective mobilisation protocols and efficient use of apheresis machines has caused peripheral blood progenitor cells (PBPC) transplantation to grow rapidly. The development of apheresis technology has improved over the years. Today PBSC procedures have changed towards systems to minimise operator interaction and to reduce the collection of undesired cells such as polymorphonuclear cells and platelets using functionally closed, sterile environments for PBSC collection in keeping with Good Manufacturing Practice guidelines. Blood cell separators with continuous flow technique allow the processing of more blood than intermittent flow devices resulting in higher PBSC yields. Large volume leukapheresis with the processing of 3-4-fold donor's/patient's blood volume can increase the number of collected progenitor cells. Therefore, intermittent flow cell separators are indicated if only single vein access is available. Anticoagulant induced hypocalcaemia is an often observed side effect in long lasting PBPC harvesting and monitoring of electrolytes should be performed especially at the end of the apheresis procedure to supplement low levels of potassium, calcium or magnesium. Refinement and improvement of collection techniques continue to add to the armamentarium of current approaches for cancer and non-malignant conditions and will enable future strategies.

  2. Peripheral blood CD34+ cell count reliably predicts autograft yield.

    PubMed

    Chapple, P; Prince, H M; Quinn, M; Bertoncello, I; Juneja, S; Wolf, M; Januszewicz, H; Brettell, M; Gardyn, J; Seymour, C; Venter, D

    1998-07-01

    A reliable measure to predict peripheral blood progenitor cell (PBPC) autograft CD34+ cell content is required to optimize the timing of PBPC collection. We prospectively examined the peripheral blood (PB) CD34+ cell count in 59 consecutive patients with various malignancies and analyzed the correlation between the PB CD34+ cell count and various parameters in the PBPC autograft. Two hundred and thirty-five collections were performed with a median of 4.0 collections per patient (range, 2-10). The median PB CD34+ cell count at the time of collection was 39 x 10(6)/1 (range, 0.0-285.6). The PBPC autograft parameters measured were the CD34+ cell, colony-forming unit granulocyte-macrophage (CFU-GM) and mononuclear cell (MNC) content. There was a strong linear correlation between PB CD34+ cells/l and autograft CD34+ cells/kg (r = 0.8477). The correlation with CFU-GM/kg (r = 0.5512) was weaker. There was no correlation between autograft CD34+ cells/kg and PB WBC (r= 0.0684), PB MNC (r = 0.1518) or PB platelet count (r = 0.2010). At our institution we aim to obtain a minimum of 0.5 x 10(6) CD34+ cells/kg with each day of collection. We demonstrate that such a collection can be reliably obtained if the PB CD34+ cell count exceeds 5.0 x 10(6)/l.

  3. A smart core-sheath nanofiber that captures and releases red blood cells from the blood.

    PubMed

    Shi, Q; Hou, J; Zhao, C; Xin, Z; Jin, J; Li, C; Wong, S-C; Yin, J

    2016-01-28

    A smart core-sheath nanofiber for non-adherent cell capture and release is demonstrated. The nanofibers are fabricated by single-spinneret electrospinning of poly(N-isopropylacrylamide) (PNIPAAm), polycaprolactone (PCL) and nattokinase (NK) solution blends. The self-assembly of PNIPAAm and PCL blends during the electrospinning generates the core-sheath PCL/PNIPAAm nanofibers with PNIPAAm as the sheath. The PNIPAAm-based core-sheath nanofibers are switchable between hydrophobicity and hydrophilicity with temperature change and enhance stability in the blood. When the nanofibers come in contact with blood, the NK is released from the nanofibers to resist platelet adhesion on the nanofiber surface, facilitating the direct capture and isolation of red blood cells (RBCs) from the blood above phase-transition temperature of PNIPAAm. Meanwhile, the captured RBCs are readily released from the nanofibers with temperature stimuli in an undamaged manner. The release efficiency of up to 100% is obtained while maintaining cellular integrity and function. This work presents promising nanofibers to effectively capture non-adherent cells and release for subsequent molecular analysis and diagnosis of single cells.

  4. Nanofiber Expansion of Umbilical Cord Blood Hematopoietic Stem Cells

    PubMed Central

    Eskandari, F; Allahverdi, A; Nasiri, H; Azad, M; Kalantari, N; Soleimani, M; Zare-Zardini, H

    2015-01-01

    Background The aim of this study was the ex vivo expansion of Umbilical Cord Blood hematopoietic stem cells on biocompatible nanofiber scaffolds. Materials and Methods CD133+ hematopoietic stem cells were separated from umbilical cord blood using MidiMacs (positive selection) system by means of monocolonal antibody CD133 (microbeads); subsequently, flowcytometry method was done to assess the purity of separated cells. Isolated cells were cultured on plate (2 Dimensional) and fibronectin conjugated polyethersulfon nanofiber scaffold, simultaneously (3 Dimensional). Colony assay test was performed to show colonization ability of expanded cells. Results Cell count analysis revealed that expansion of hematopoietic stem cells in 2dimensional (2D) environment was greater than 3dimensional (3D) condition (p= 0.01). Assessment of stem cell- phenotype after expansions was performed by flowcytometric analysis which is showed that the maintenance of CD133 marker in expanded cells in 3 dimensional condition were higher than expanded cells in 2 dimensional condition (p=0.01). Moreover, colony assay test was performed before and after of expansion to show colonization ability of expanded cells both in 3D and 2D culture and results revealed more ability of 3D culture compared with 2D culture (p= 0.03). Conclusion The results of current study confirmed that umbilical cord blood CD133+ haematopoietic stem cells are able to expand on fibronectin conjugated polyethersulfon scaffold. These findings indicated that 3D is a proper and valuable cell culture system for hematopoietic stem cells expansion, compared to 2D in invitro situation. PMID:26985349

  5. Comparative study of red blood cell method in rat and calves blood as alternatives of Draize eye irritation test.

    PubMed

    Lagarto, A; Vega, R; Vega, Y; Guerra, I; González, R

    2006-06-01

    Red blood cell assay (RBC) is used to estimate potential irritation of tensioactive agents and detergents. Cell membrane lysis and cell protein denaturation are measured photometrically. This study was aimed to determine if rat blood cells can be used to predict eye potential irritation in the same way of calves blood cells in RBC assay. We evaluated 20 cosmetic formulations using rat and calves blood according to INVITOX protocol No 37. Data of media hemolysis concentration, denaturation index and the ratio of both parameters were compared with in vivo data of eye irritancy. There was a significant difference (p<0.01) between H50 value when evaluated the standard SDS with red blood cell method in rat and calves blood. According to the exact probability of Fisher taking as approach the acceptance or rejection of the substance there are no significant differences between in vitro assay with calves blood and in vivo results. Not happening the same way for the RBC assay with rat blood where significant differences were obtained (p<0.01) among the classification of in vitro and in vivo test. The RBC assay using calves blood showed better results. Several test substances were false negatives with rat blood. This high false negative rate would be correctly identified by the animal test but it may also lead to increased animal consumption. For that RBC assay with calf blood cells is preferable to the employment of rat blood as screening method with a reduction and refinement strategy.

  6. A color and shape based algorithm for segmentation of white blood cells in peripheral blood and bone marrow images.

    PubMed

    Arslan, Salim; Ozyurek, Emel; Gunduz-Demir, Cigdem

    2014-06-01

    Computer-based imaging systems are becoming important tools for quantitative assessment of peripheral blood and bone marrow samples to help experts diagnose blood disorders such as acute leukemia. These systems generally initiate a segmentation stage where white blood cells are separated from the background and other nonsalient objects. As the success of such imaging systems mainly depends on the accuracy of this stage, studies attach great importance for developing accurate segmentation algorithms. Although previous studies give promising results for segmentation of sparsely distributed normal white blood cells, only a few of them focus on segmenting touching and overlapping cell clusters, which is usually the case when leukemic cells are present. In this article, we present a new algorithm for segmentation of both normal and leukemic cells in peripheral blood and bone marrow images. In this algorithm, we propose to model color and shape characteristics of white blood cells by defining two transformations and introduce an efficient use of these transformations in a marker-controlled watershed algorithm. Particularly, these domain specific characteristics are used to identify markers and define the marking function of the watershed algorithm as well as to eliminate false white blood cells in a postprocessing step. Working on 650 white blood cells in peripheral blood and bone marrow images, our experiments reveal that the proposed algorithm improves the segmentation performance compared with its counterparts, leading to high accuracies for both sparsely distributed normal white blood cells and dense leukemic cell clusters. © 2014 International Society for Advancement of Cytometry.

  7. Endothelial colony forming cells and mesenchymal progenitor cells form blood vessels and increase blood flow in ischemic muscle.

    PubMed

    Kang, Kyu-Tae; Lin, Ruei-Zeng; Kuppermann, David; Melero-Martin, Juan M; Bischoff, Joyce

    2017-04-10

    Here we investigated whether endothelial colony forming cells (ECFC) and mesenchymal progenitor cells (MPC) form vascular networks and restore blood flow in ischemic skeletal muscle, and whether host myeloid cells play a role. ECFC + MPC, ECFC alone, MPC alone, or vehicle alone were injected into the hind limb ischemic muscle one day after ligation of femoral artery and vein. At day 5, hind limbs injected with ECFC + MPC showed greater blood flow recovery compared with ECFC, MPC, or vehicle. Tail vein injection of human endothelial specific Ulex europaeus agglutinin-I demonstrated an increased number of perfused human vessels in ECFC + MPC compared with ECFC. In vivo bioluminescence imaging showed ECFC persisted for 14 days in ECFC + MPC-injected hind limbs. Flow cytometric analysis of ischemic muscles at day 2 revealed increased myeloid lineage cells in ECFC + MPC-injected muscles compared to vehicle-injected muscles. Neutrophils declined by day 7, while the number of myeloid cells, macrophages, and monocytes did not. Systemic myeloid cell depletion with anti-Gr-1 antibody blocked the improved blood flow observed with ECFC + MPC and reduced ECFC and MPC retention. Our data suggest that ECFC + MPC delivery could be used to reestablish blood flow in ischemic tissues, and this may be enhanced by coordinated recruitment of host myeloid cells.

  8. Continuous separation of blood cells in spiral microfluidic devices

    PubMed Central

    Nivedita, Nivedita; Papautsky, Ian

    2013-01-01

    Blood cell sorting is critical to sample preparation for both clinical diagnosis and therapeutic research. The spiral inertial microfluidic devices can achieve label-free, continuous separation of cell mixtures with high throughput and efficiency. The devices utilize hydrodynamic forces acting on cells within laminar flow, coupled with rotational Dean drag due to curvilinear microchannel geometry. Here, we report on optimized Archimedean spiral devices to achieve cell separation in less than 8 cm of downstream focusing length. These improved devices are small in size (<1 in.2), exhibit high separation efficiency (∼95%), and high throughput with rates up to 1 × 106 cells per minute. These device concepts offer a path towards possible development of a lab-on-chip for point-of-care blood analysis with high efficiency, low cost, and reduced analysis time. PMID:24404064

  9. Mesenchymal Stem Cells in ex vivo Cord Blood Expansion

    PubMed Central

    Robinson, Simon N.; Simmons, Paul J.; Yang, Hong; Alousi, Amin M; de Lima, Marcos J.

    2013-01-01

    Umbilical cord blood (CB) is becoming an important source of haematopoietic support for transplant patients lacking human leukocyte antigen matched donors. The ethnic diversity, relative ease of collection, ready availability as cryopreserved units from CB banks, reduced incidence and severity of graft versus host disease and tolerance of higher degrees of HLA disparity between donor and recipient, are positive attributes when compared to bone marrow or cytokine-mobilized peripheral blood. However, CB transplantation is associated with significantly delayed neutrophil and platelet engraftment and an elevated risk of graft failure. These hurdles are thought to be due, at least in part, to low total nucleated cell and CD34+ cell doses transplanted. Here, current strategies directed at improving TNC and CD34+ cell doses at transplant are discussed, with particular attention paid to the use of a mesenchymal stem cell (MSC)/CB mononuclear cell ex vivo co-culture expansion system. PMID:21396596

  10. State of the science of blood cell labeling

    SciTech Connect

    Srivastava, S.C.; Straub, R.F.

    1989-01-01

    Blood cell labeling can be considered a science in as far as it is based on precise knowledge and can be readily reproduced. This benchmark criterion is applied to all current cell labeling modalities and their relative merits and deficiencies are discussed. Mechanisms are given where they are known as well as labeling yields, label stability, and cell functionality. The focus is on the methodology and its suitability to the clinical setting rather than on clinical applications per se. Clinical results are cited only as proof of efficacy of the various methods. The emphasis is on technetium as the cell label, although comparisons are made between technetium and indium, and all blood cells are covered. 52 refs., 6 figs., 7 tabs.

  11. Blood stem cell products: toward sustainable benchmarks for clinical translation.

    PubMed

    Csaszar, Elizabeth; Cohen, Sandra; Zandstra, Peter W

    2013-03-01

    Robust ex vivo expansion of umbilical cord blood (UCB) derived hematopoietic stem and progenitor cells (HSPCs) should enable the widespread use of UCB as a source of cells to treat hematologic and immune diseases. Novel approaches for HSPC expansion have recently been developed, setting the stage for the production of blood stem cell derived products that fulfill our current best known criteria of clinical relevance. Translating these technologies into clinical use requires bioengineering strategies to overcome challenges of scale-up, reproducibility, and product quality assurance. Clinical-scale implementation should also define criteria and targets for cost-effective cell manufacturing. As production strategies become more effective, new opportunities in the therapeutic use of ex vivo expanded hematopoietic cell products will emerge. Herein we examine key technological milestones that need to be met in order to move ex vivo expanded HSPC therapies from the bench-top to the bedside in a robust and reliable manner.

  12. Nanostructured Substrates for Capturing Circulating Tumor Cells in Whole Blood

    NASA Astrophysics Data System (ADS)

    Tseng, Hsian-Rong

    2009-03-01

    Over the past decade, circulating tumor cells (CTCs) has become an emerging ``biomarker'' for detecting early-stage cancer metastasis, predicting patient prognosis, as well as monitoring disease progression and therapeutic outcomes. However, isolation of CTCs has been technically challenging due to the extremely low abundance (a few to hundreds per ml) of CTCs among a high number of hematologic cells (109 per mL) in the blood. Our joint research team at UCLA has developed a new cell capture technology for quantification of CTCs in whole blood samples. Similar to most of the existing approaches, epithelial cell adhesion molecule antibody (anti-EpCAM) was grafted onto the surfaces to distinguish CTCs from the surrounding hematologic cells. The uniqueness of our technology is the use of nanostructured surfaces, which facilitates local topographical interactions between CTCs and substrates at the very first cell/substrate contacting time point. We demonstrated the ability of these nanostructured substrates to capture CTCs in whole blood samples with significantly improved efficiency and selectivity. The successful demonstration of this cell capture technology using brain, breast and prostate cancer cell lines encouraged us to test this approach in clinical setting. We have been able to bond our first validation study with a commercialized technology based on the use of immunomagnetic nanoparticles. A group of clinically well-characterized prostate cancer patients at UCLA hospital have been recruited and tested in parallel by these two technologies.

  13. Photoacoustic response of suspended and hemolyzed red blood cells

    NASA Astrophysics Data System (ADS)

    Saha, Ratan K.; Karmakar, Subhajit; Roy, Madhusudan

    2013-07-01

    The effect of confinement of hemoglobin molecules on photoacoustic (PA) signal is studied experimentally. The PA amplitudes for samples with suspended red blood cells (SRBCs) and hemolyzed red blood cells (HRBCs) were found to be comparable at each hematocrit for 532 nm illumination. The difference between the corresponding amplitudes increased with increasing hematocrit for 1064 nm irradiation. For example, the PA amplitude for the SRBCs was about 260% higher than that of the HRBCs at 40% hematocrit. This observation may help to develop a PA method detecting hemolysis noninvasively.

  14. Fibrinogen, red blood cells, and factor XIII in venous thrombosis.

    PubMed

    Walton, B L; Byrnes, J R; Wolberg, A S

    2015-06-01

    Cardiovascular disease is the leading cause of death and disability worldwide. Among cardiovascular causes of death, venous thrombosis (VT) is ranked third most common in the world. Venous thrombi have high red blood cell and fibrin content; however, the pathophysiologic mechanisms that contribute to venous thrombus composition and stability are still poorly understood. This article reviews biological, biochemical, and biophysical contributions of fibrinogen, factor XIII, and red blood cells to VT, and new evidence suggesting interactions between these components mediate venous thrombus composition and size.

  15. Transfusion of fresher versus older red blood cells for all conditions.

    PubMed

    Brunskill, Susan J; Wilkinson, Kirstin L; Doree, Carolyn; Trivella, Marialena; Stanworth, Simon

    2015-05-12

    Red blood cell transfusion is a common treatment for anaemia in many clinical conditions. One current concern is uncertainty as to the clinical consequences (notably efficacy and safety) of transfusing red blood cell units that have been stored for different durations of time before a transfusion. If evidence from randomised controlled trials were to indicate that clinical outcomes are affected by storage age, the implications for inventory management and clinical practice would be significant. To assess the effects of using fresher versus older red blood cells in people requiring a red blood cell transfusion. We ran the search on 29th September 2014. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (OvidSP), Embase (OvidSP), CINAHL (EBSCO), PubMed (for e-publications), three other databases and trial registers. We included randomised controlled trials comparing fresher red blood cell transfusion versus active transfusion of older red blood cells, and comparing fresher red blood cell transfusion versus current standard practice. All definitions of 'fresher' and 'older'/'standard practice' red blood cells were included. Two review authors independently assessed trial quality and extracted from the trial report data on adverse red blood cell transfusion reactions, when reported. We included 16 trials (1864 participants) in the review. Eight trials (279 participants) compared transfusion of fresher red blood cells versus transfusion of older stored red blood cells ('fresher' vs 'older'). Eight trials (1585 participants) compared the transfusion of fresher red blood cells versus current standard practice ('fresher' vs 'standard practice'). Five trials enrolled neonates, one trial enrolled children and 12 trials enrolled adults. Overall sample sizes were small: only two trials randomly assigned more than 100 participants.We performed no meta-analyses for a variety of reasons: no uniform definition of 'fresher' or 'older' red blood cell

  16. Gene expression analysis of whole blood, peripheral blood mononuclear cells, and lymphoblastoid cell lines from the Framingham Heart Study

    PubMed Central

    Joehanes, Roby; Johnson, Andrew D.; Barb, Jennifer J.; Raghavachari, Nalini; Liu, Poching; Woodhouse, Kimberly A.; O'Donnell, Christopher J.; Munson, Peter J.

    2012-01-01

    Despite a growing number of reports of gene expression analysis from blood-derived RNA sources, there have been few systematic comparisons of various RNA sources in transcriptomic analysis or for biomarker discovery in the context of cardiovascular disease (CVD). As a pilot study of the Systems Approach to Biomarker Research (SABRe) in CVD Initiative, this investigation used Affymetrix Exon arrays to characterize gene expression of three blood-derived RNA sources: lymphoblastoid cell lines (LCL), whole blood using PAXgene tubes (PAX), and peripheral blood mononuclear cells (PBMC). Their performance was compared in relation to identifying transcript associations with sex and CVD risk factors, such as age, high-density lipoprotein, and smoking status, and the differential blood cell count. We also identified a set of exons that vary substantially between participants, but consistently in each RNA source. Such exons are thus stable phenotypes of the participant and may potentially become useful fingerprinting biomarkers. In agreement with previous studies, we found that each of the RNA sources is distinct. Unlike PAX and PBMC, LCL gene expression showed little association with the differential blood count. LCL, however, was able to detect two genes related to smoking status. PAX and PBMC identified Y-chromosome probe sets similarly and slightly better than LCL. PMID:22045913

  17. Cell salvage in obstetrics: an evaluation of the ability of cell salvage combined with leucocyte depletion filtration to remove amniotic fluid from operative blood loss at caesarean section.

    PubMed

    Catling, S J; Williams, S; Fielding, A M

    1999-04-01

    During 27 elective caesarean sections, operative blood loss was collected and processed using the Haemonetics Cell Saver 5 and filtered by Pall RC 100 leucocyte depletion filtration. The efficiency of removal of amniotic fluid, and the degree. of contamination with fetal red cells were assessed in the resulting 'cleaned' blood. Cell saver processing effectively removed alpha-fetoprotein from the red cells of 14 patients whose amniotic fluid was removed by separate suction and from nine of the 13 patients whose amniotic fluid was aspirated into the cell saver along with operative blood loss. Cell saver processing and leucocyte depletion filtration completely removed trophoblastic tissue and white cells, but fetal squames were still clearly present in 10, and possibly in 14 samples after processing and fully removed in only two specimens. Amorphous debris was present in all samples after processing. The maximum mass of fetal red cells contaminating any patient's total salvaged blood was 19 ml (range 2-19 ml). Had this been re-transfused into a rhesus-incompatible mother it would have required 2500 i.u. (500 microg) anti-D immunoglobulin to prevent rhesus-immunization of the mother. Contamination of processed caesarean section blood with fetal red cells and fetal squames is defined and its clinical implications discussed, with an overview of the development and current status of cell salvage. Autotransfusion by cell salvage with leucocyte depletion filtration should be considered in life-threatening obstetric haemorrhage and offered to Jehovah's Witnesses.

  18. Determination of blood cell subtype concentrations from frozen whole blood samples using TruCount beads.

    PubMed

    Langenskiöld, Cecilia; Mellgren, Karin; Abrahamsson, Jonas; Bemark, Mats

    2016-06-24

    In many studies it would be advantageous if blood samples could be collected and analyzed using flow cytometry at a later stage. Ideally, sample collection should involve little hands-on time, allow for long-term storage, and minimally influence the samples. Here we establish a flow cytometry antibody panel that can be used to determine granulocytes, monocytes, and lymphocyte subset concentrations in fresh and frozen whole blood using TruCount technology. The panel can be used on fresh whole-blood samples as well as whole-blood samples that have been frozen after mixing with 10% DMSO. Concentrations in frozen and fresh sample is highly correlated both when frozen within 4 h and the day after collection (r ≥ 0.98), and the estimated concentration in frozen samples was between 91 and 94% of that in fresh samples for all cell types. Using this method whole-blood samples can be frozen using a simple preparation method, and stored long-term before accurate determination of cell concentration. This allows for standardized analysis of the samples at a reference laboratory in multi-center studies. © 2016 International Clinical Cytometry Society. © 2016 International Clinical Cytometry Society.

  19. In-Depth Profiling of the Peripheral Blood Mononuclear Cells Proteome for Clinical Blood Proteomics

    PubMed Central

    Končarević, Saša; Lößner, Christopher; Pike, Ian; Zucht, Hans-Dieter

    2014-01-01

    Peripheral blood mononuclear cells (PBMCs) are an easy accessible cellular part of the blood organ and, along with platelets, represent the only site of active gene expression in blood. These cells undergo immunophenotypic changes in various diseases and represent a peripheral source of monitoring gene expression and posttranslational modifications relevant to many diseases. Little is known about the source of many blood proteins and we hypothesise that release from PBMCs through active and passive mechanisms may account for a substantial part of the plasma proteome. The use of state-of-the-art proteomic profiling methods in PBMCs will enable minimally invasive monitoring of disease progression or response to treatment and discovery of biomarkers. To achieve this goal, detailed mapping of the PBMC proteome using a sensitive, robust, and quantitative methodological setup is required. We have applied an indepth gel-free proteomics approach using tandem mass tags (TMT), unfractionated and SCX fractionated PBMC samples, and LC-MS/MS with various modulations. This study represents a benchmark in deciphering the PBMC proteome as we provide a deep insight by identifying 4129 proteins and 25503 peptides. The identified proteome defines the scope that enables PBMCs to be characterised as cellular major biomarker pool within the blood organ. PMID:24724028

  20. In-depth profiling of the peripheral blood mononuclear cells proteome for clinical blood proteomics.

    PubMed

    Končarević, Saša; Lößner, Christopher; Kuhn, Karsten; Prinz, Thorsten; Pike, Ian; Zucht, Hans-Dieter

    2014-01-01

    Peripheral blood mononuclear cells (PBMCs) are an easy accessible cellular part of the blood organ and, along with platelets, represent the only site of active gene expression in blood. These cells undergo immunophenotypic changes in various diseases and represent a peripheral source of monitoring gene expression and posttranslational modifications relevant to many diseases. Little is known about the source of many blood proteins and we hypothesise that release from PBMCs through active and passive mechanisms may account for a substantial part of the plasma proteome. The use of state-of-the-art proteomic profiling methods in PBMCs will enable minimally invasive monitoring of disease progression or response to treatment and discovery of biomarkers. To achieve this goal, detailed mapping of the PBMC proteome using a sensitive, robust, and quantitative methodological setup is required. We have applied an indepth gel-free proteomics approach using tandem mass tags (TMT), unfractionated and SCX fractionated PBMC samples, and LC-MS/MS with various modulations. This study represents a benchmark in deciphering the PBMC proteome as we provide a deep insight by identifying 4129 proteins and 25503 peptides. The identified proteome defines the scope that enables PBMCs to be characterised as cellular major biomarker pool within the blood organ.

  1. Related Hematopoietic Stem Cell Transplantation (HSCT) for Genetic Diseases of Blood Cells

    ClinicalTrials.gov

    2017-01-12

    Stem Cell Transplantation; Bone Marrow Transplantation; Peripheral Blood Stem Cell Transplantation; Allogeneic Transplantation; Genetic Diseases; Thalassemia; Pediatrics; Diamond-Blackfan Anemia; Combined Immune Deficiency; Wiskott-Aldrich Syndrome; Chronic Granulomatous Disease; X-linked Lymphoproliferative Disease; Metabolic Diseases

  2. Thrombin regulates the function of human blood dendritic cells

    SciTech Connect

    Yanagita, Manabu; Kobayashi, Ryohei; Kashiwagi, Yoichiro; Shimabukuro, Yoshio; Murakami, Shinya E-mail: ipshinya@dent.osaka-u.ac.jp

    2007-12-14

    Thrombin is the key enzyme in the coagulation cascade and activates endothelial cells, neutrophils and monocytes via protease-activated receptors (PARs). At the inflammatory site, immune cells have an opportunity to encounter thrombin. However little is known about the effect of thrombin for dendritic cells (DC), which are efficient antigen-presenting cells and play important roles in initiating and regulating immune responses. The present study revealed that thrombin has the ability to stimulate blood DC. Plasmacytoid DC (PDC) and myeloid DC (MDC) isolated from PBMC expressed PAR-1 and released MCP-1, IL-10, and IL-12 after thrombin stimulation. Unlike blood DC, monocyte-derived DC (MoDC), differentiated in vitro did not express PAR-1 and were unresponsive to thrombin. Effects of thrombin on blood DC were significantly diminished by the addition of anti-PAR-1 Ab or hirudin, serine protease inhibitor. Moreover, thrombin induced HLA-DR and CD86 expression on DC and the thrombin-treated DC induced allogenic T cell proliferation. These findings indicate that thrombin plays a role in the regulation of blood DC functions.

  3. Dynamic deformability of sickle red blood cells in microphysiological flow.

    PubMed

    Alapan, Y; Matsuyama, Y; Little, J A; Gurkan, U A

    2016-06-01

    In sickle cell disease (SCD), hemoglobin molecules polymerize intracellularly and lead to a cascade of events resulting in decreased deformability and increased adhesion of red blood cells (RBCs). Decreased deformability and increased adhesion of sickle RBCs lead to blood vessel occlusion (vaso-occlusion) in SCD patients. Here, we present a microfluidic approach integrated with a cell dimensioning algorithm to analyze dynamic deformability of adhered RBC at the single-cell level in controlled microphysiological flow. We measured and compared dynamic deformability and adhesion of healthy hemoglobin A (HbA) and homozygous sickle hemoglobin (HbS) containing RBCs in blood samples obtained from 24 subjects. We introduce a new parameter to assess deformability of RBCs: the dynamic deformability index (DDI), which is defined as the time-dependent change of the cell's aspect ratio in response to fluid flow shear stress. Our results show that DDI of HbS-containing RBCs were significantly lower compared to that of HbA-containing RBCs. Moreover, we observed subpopulations of HbS containing RBCs in terms of their dynamic deformability characteristics: deformable and non-deformable RBCs. Then, we tested blood samples from SCD patients and analyzed RBC adhesion and deformability at physiological and above physiological flow shear stresses. We observed significantly greater number of adhered non-deformable sickle RBCs than deformable sickle RBCs at flow shear stresses well above the physiological range, suggesting an interplay between dynamic deformability and increased adhesion of RBCs in vaso-occlusive events.

  4. Cytochemical characteristics of blood cells from Brazilian tortoises (Testudines: Testudinidae).

    PubMed

    Martins, G S; Alevi, K C C; Azeredo-Oliveira, M T V; Bonini-Domingos, C R

    2016-03-18

    The hematology of wild and captive animals is essential for obtaining details about species and represents a simple method of diagnosing disease and determining prognosis. Few studies have described the morphology of chelonian blood cells, which are more common in sea and freshwater turtle species. Thus, in order to further our understanding and recognition of different chelonian cells types, the present study aimed to describe blood cells from the two species of Brazilian tortoises, Chelonoidis carbonarius and C. denticulatus. Cytochemical analysis of tortoise blood tissue with Panótico®, made it possible to describe all the of the chelonian cell types (with the exception of thrombocytes): erythrocytes, agranular leukocytes (monocytes and lymphocytes), and granular leukocytes (eosinophils, heterophils, basophils, and azurophils). These data are of high importance for establishing hematological profiles of Brazilian tortoises and reptiles. Therefore, based on our results and on comparative analyses with data from the literature for other reptile species, we can conclude that the blood cells described for Brazilian tortoises are found in all species of reptiles that have been analyzed thus far, and may be characterized and used as a comparative parameter between different groups to evaluate the health status of these animals.

  5. Nanoparticle encapsulation in red blood cells enables blood-pool magnetic particle imaging hours after injection

    NASA Astrophysics Data System (ADS)

    Rahmer, J.; Antonelli, A.; Sfara, C.; Tiemann, B.; Gleich, B.; Magnani, M.; Weizenecker, J.; Borgert, J.

    2013-06-01

    Magnetic particle imaging (MPI) is a new medical imaging approach that is based on the nonlinear magnetization response of super-paramagnetic iron oxide nanoparticles (SPIOs) injected into the blood stream. To date, real-time MPI of the bolus passage of an approved MRI SPIO contrast agent injected into the tail vein of living mice has been demonstrated. However, nanoparticles are rapidly removed from the blood stream by the mononuclear phagocyte system. Therefore, imaging applications for long-term monitoring require the repeated administration of bolus injections, which complicates quantitative comparisons due to the temporal variations in concentration. Encapsulation of SPIOs into red blood cells (RBCs) has been suggested to increase the blood circulation time of nanoparticles. This work presents first evidence that SPIO-loaded RBCs can be imaged in the blood pool of mice several hours after injection using MPI. This finding is supported by magnetic particle spectroscopy performed to quantify the iron concentration in blood samples extracted from the mice 3 and 24 h after injection of SPIO-loaded RBCs. Based on these results, new MPI applications can be envisioned, such as permanent 3D real-time visualization of the vessel tree during interventional procedures, bleeding monitoring after stroke, or long-term monitoring and treatment control of cardiovascular diseases.

  6. Synthetic glycolipid modification of red blood cell membranes.

    PubMed

    Frame, Tom; Carroll, Tim; Korchagina, Elena; Bovin, Nicolai; Henry, Stephen

    2007-05-01

    Glycolipids have a natural ability to insert into red cell (RBC) membranes. Based on this concept the serology of RBCs modified with synthetic analogs of blood group glycolipids (KODE technology) was developed, which entails making synthetic glycolipid constructs engineered to have specific performance criteria. Such synthetic constructs can be made to express a potentially unlimited range of carbohydrate blood group determinants. Synthetic constructs incorporating A, B, acquired-B, and Le(a) blood group determinants were constructed and used to modify RBCs. Modified cells were assessed by routine serologic methods using a range of commercially available monoclonal antibodies. RBCs modified with different concentrations of synthetic glycolipids were able to give controllable serologic results. Synthetic A and B modified cells were able to be created to represent the serology of "weak" subgroups. Specialized cells such as those bearing synthetic acquired-B antigen reacted as expected, but also exhibited extended features due to the cells bearing only specific antigen. Synthetic Le(a)-modified cells reacted as expected with anti-Le(a) reagents, but unexpectedly, were also able to detect the chemical anti-Le(ab) specificity of serologic monoclonal anti-Le(b) reagents. RBCs can be created to express normal and novel carbohydrate profiles by inserting synthetic glycolipids into them. Such cells will be useful in creating specialized antigen panels and for quality control purposes.

  7. Cord Blood as a Source of Natural Killer Cells

    PubMed Central

    Mehta, Rohtesh S.; Shpall, Elizabeth J.; Rezvani, Katayoun

    2016-01-01

    Cord blood (CB) offers several unique advantages as a graft source for hematopoietic stem cell transplantation (HSCT). The risk of relapse and graft vs. host disease after cord blood transplantation (CBT) is lower than what is typically observed after other graft sources with a similar degree of human leukocyte antigen mismatch. Natural killer (NK) cells have a well-defined role in both innate and adaptive immunity and as the first lymphocytes to reconstitute after HSCT and CBT, and they play a significant role in protection against early relapse. In this article, we highlight the uses of CB NK cells in transplantation and adoptive immunotherapy. First, we will describe differences in the phenotype and functional characteristics of NK cells in CB as compared with peripheral blood. Then, we will review some of the obstacles we face in using resting CB NK cells for adoptive immunotherapy, and discuss methods to overcome them. We will review the current literature on killer-cell immunoglobulin-like receptors ligand mismatch and outcomes after CBT. Finally, we will touch on current strategies for the use of CB NK cells in cellular immunotherapy. PMID:26779484

  8. Characterization at the individual cell level and in whole blood samples of shear stress preventing red blood cells aggregation.

    PubMed

    Lee, K; Kinnunen, M; Danilina, A V; Ustinov, V D; Shin, S; Meglinski, I; Priezzhev, A V

    2016-05-03

    The aggregation of red blood cells (RBC) is an intrinsic feature of blood that has a strong impact on its microcirculation. For a number of years it has been attracting a great attention in basic research and clinical studies. Here, we study a relationship between the RBC aggregation parameters measured at the individual cell level and in a whole blood sample. The home made optical tweezers were used to measure the aggregating and disaggregating forces for a pair of interacting RBCs, at the individual cell level, in order to evaluate the corresponding shear stresses. The RheoScan aggregometer was used for the measurements of critical shear stress (CSS) in whole blood samples. The correlation between CSS and the shear stress required to stop an RBC pair from aggregating was found. The shear stress required to disaggregate a pair of RBCs using the double channel optical tweezers appeared to be about 10 times higher than CSS. The correlation between shear stresses required to prevent RBCs from aggregation at the individual cell level and in whole blood samples was estimated and assessed quantitatively. The experimental approach developed has a high potential for advancing hemorheological studies.

  9. White blood cell counting analysis of blood smear images using various segmentation strategies

    NASA Astrophysics Data System (ADS)

    Safuan, Syadia Nabilah Mohd; Tomari, Razali; Zakaria, Wan Nurshazwani Wan; Othman, Nurmiza

    2017-09-01

    In white blood cell (WBC) diagnosis, the most crucial measurement parameter is the WBC counting. Such information is widely used to evaluate the effectiveness of cancer therapy and to diagnose several hidden infection within human body. The current practice of manual WBC counting is laborious and a very subjective assessment which leads to the invention of computer aided system (CAS) with rigorous image processing solution. In the CAS counting work, segmentation is the crucial step to ensure the accuracy of the counted cell. The optimal segmentation strategy that can work under various blood smeared image acquisition conditions is remain a great challenge. In this paper, a comparison between different segmentation methods based on color space analysis to get the best counting outcome is elaborated. Initially, color space correction is applied to the original blood smeared image to standardize the image color intensity level. Next, white blood cell segmentation is performed by using combination of several color analysis subtraction which are RGB, CMYK and HSV, and Otsu thresholding. Noises and unwanted regions that present after the segmentation process is eliminated by applying a combination of morphological and Connected Component Labelling (CCL) filter. Eventually, Circle Hough Transform (CHT) method is applied to the segmented image to estimate the number of WBC including the one under the clump region. From the experiment, it is found that G-S yields the best performance.

  10. Postprandial alterations in whole-blood DNA methylation are mediated by changes in white blood cell composition.

    PubMed

    Rask-Andersen, Mathias; Bringeland, Nathalie; Nilsson, Emil K; Bandstein, Marcus; Olaya Búcaro, Marcela; Vogel, Heike; Schürmann, Annette; Hogenkamp, Pleunie S; Benedict, Christian; Schiöth, Helgi B

    2016-08-01

    DNA methylation is an essential nuclear process associated with genomic functions such as transcription factor binding and the regulation of gene expression. DNA methylation patterns can also serve as potential biomarkers for disease progression and response to therapy. However, the full dynamics of DNA methylation across daily physiologic events have not been fully elucidated. We sought to study how ingesting a standardized meal acutely affects peripheral blood DNA methylation. We performed an observational study in healthy men (n = 26) on DNA methylation and gene expression in whole blood before and 160 min after the ingestion of a standardized meal. Cytosine-phosphate-guanine (CpG) methylation was assayed on the HumanMethylation450k microarray, and gene expression was measured with the Human Gene 2.1 ST Array. Differential methylation after food intake was detected in 13% of the analyzed probes (63,207 CpG probes) at a 5% false discovery rate (FDR). This effect was driven by changes in leukocyte fractions as estimated from comparisons against methylation datasets generated from sorted leukocytes. When methylation values were adjusted for estimated leukocyte fractions, 541 probes were observed to be altered in the postprandial state (5% FDR). Apparent alterations in DNA methylation 160 min after meal ingestion mainly reflect changes in the estimated leukocyte population in whole blood. These results have major methodologic implications for genome-wide methylation studies because they highlight the strong underlying effects of changes in leukocyte fractions on CpG methylation patterns as well as the potential importance of meal-standardized sampling procedures for future investigations when alterations in white blood cell fractions are unavailable. This trial was registered at clinicaltrials.gov as LSF008786. © 2016 American Society for Nutrition.

  11. Identification of novel dendritic cell subset markers in human blood.

    PubMed

    Schütz, Fabian; Hackstein, Holger

    2014-01-10

    Human dendritic cells (DC) are key regulators of innate and adaptive immunity that can be divided in at least three major subpopulations: plasmacytoid DC (pDC), myeloid type 1 DC (mDC1) and myeloid type 2 DC (mDC2) exhibiting different functions. However, research, diagnostic and cell therapeutic studies on human DC subsets are limited because only few DC subset markers have been identified so far. Especially mDC2 representing the rarest blood DC subset are difficult to be separated from mDC1 and pDC due to a paucity of mDC2 markers. We have combined multiparameter flow cytometry analysis of human blood DC subsets with systematic expression analysis of 332 surface antigens in magnetic bead-enriched blood DC samples. The initial analysis revealed eight novel putative DC subset markers CD26, CD85a, CD109, CD172a, CD200, CD200R, CD275 and CD301 that were subsequently tested in bulk peripheral blood mononuclear cell (PBMC) samples from healthy blood donors. Secondary analysis of PBMC samples confirmed three novel DC subset markers CD26 (dipeptidyl peptidase IV), CD85a (Leukocyte immunoglobulin-like receptor B3) and CD275 (inducible costimulator ligand). CD85a is specifically expressed in mDC1 and CD26 and CD275 represent novel mDC2 markers. These markers will facilitate human DC subset discrimination and additionally provide insight into potentially novel DC subset-specific functions.

  12. Lattice Boltzmann Simulation of Healthy and Defective Red Blood Cell Settling in Blood Plasma.

    PubMed

    Hashemi, Z; Rahnama, M; Jafari, S

    2016-05-01

    In this paper, an attempt has been made to study sedimentation of a red blood cell (RBC) in a plasma-filled tube numerically. Such behaviors are studied for a healthy and a defective cell which might be created due to human diseases, such as diabetes, sickle-cell anemia, and hereditary spherocytosis. Flow-induced deformation of RBC is obtained using finite-element method (FEM), while flow and fluid-membrane interaction are handled using lattice Boltzmann (LB) and immersed boundary methods (IBMs), respectively. The effects of RBC properties as well as its geometry and orientation on its sedimentation rate are investigated and discussed. The results show that decreasing frontal area of an RBC and/or increasing tube diameter results in a faster settling. Comparison of healthy and diabetic cells reveals that less cell deformability leads to slower settling. The simulation results show that the sicklelike and spherelike RBCs have lower settling velocity as compared with a biconcave discoid cell.

  13. Effect of warming and flow rate conditions of blood warmers on red blood cell integrity.

    PubMed

    Poder, T G; Pruneau, D; Dorval, J; Thibault, L; Fisette, J-F; Bédard, S K; Jacques, A; Beauregard, P

    2016-11-01

    Fluid warmers are routinely used to reduce the risk of hypothermia and cardiac complications associated with the infusion of cold blood products. However, warming blood products could generate haemolysis. This study was undertaken to compare the impact of temperature of blood warmers on the per cent haemolysis of packed red blood cells (RBCs) heated at different flow rates as well as non-flow conditions. Infusion warmers used were calibrated at 41·5°C ± 0·5°C and 37·5°C ± 0·5°C. Cold RBC units stored at 4°C in AS-3 (n = 30), aged 30-39 days old, were divided into half units before being allocated under two different scenarios (i.e. infusion pump or syringe). Blood warmers were effective to warm cold RBCs to 37·5°C or 41·5°C when used in conjunction with an infusion pump at flow rate up to 600 ml/h. However, when the warmed blood was held in a syringe for various periods of time, such as may occur in neonatal transfusions, the final temperature was below the expected requirements with measurement as low as 33·1°C. Increasing the flow with an infusion pump increased haemolysis in RBCs from 0·2% to up to 2·1% at a flow rate of 600 ml/h regardless of the warming device used (P < 0·05). No relevant increase of haemolysis was observed using a syringe. The use of a blood warmer adjusted to 41·5°C is probably the best choice for reducing the risk of hypothermia for the patient without generating haemolysis. However, we should be cautious with the use of an infusion pump for RBC transfusion, particularly at high flow rates. © 2016 International Society of Blood Transfusion.

  14. Photoacoustic measurements of red blood cell oxygen saturation in blood bags in situ

    NASA Astrophysics Data System (ADS)

    Pinto, Ruben N.; Bagga, Karan; Douplik, Alexandre; Acker, Jason P.; Kolios, Michael C.

    2017-03-01

    Red blood cell (RBC) transfusion is a critical component of the health care services. RBCs are stored in blood bags in hypothermic temperatures for a maximum of 6 weeks post donation. During this in vitro storage period, RBCs have been documented to undergo changes in structure and function due to mechanical and biochemical stress. Currently, there are no assessment methods that monitor the quality of RBCs within blood bags stored for transfusion. Conventional assessment methods require the extraction of samples, consequently voiding the sterility of the blood bags and potentially rendering them unfit for transfusions. It is hypothesized that photoacoustic (PA) technology can provide a rapid and non-invasive indication of RBC quality. In this study, a novel PA setup was developed for the acquisition of oxygen saturation (SO2) of two blood bags in situ. These measurements were taken throughout the lifespan of the blood bags (42 days) and compared against the clinical gold standard method of the blood gas analyzer (BGA). SO2 values of the blood bags increased monotonically throughout the storage period. A strong correlation between PA SO2 and BGA SO2 was found, however, PA values were on average 3.5% lower. Both techniques found the bags to increase by an SO2 of approximately 20%, and measured very similar rates of SO2 change. Future work will be focused on determining the cause of discrepancy between SO2 values acquired from PA versus BGA, as well