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Sample records for blood cells implications

  1. Lessons and Implications from Genome-Wide Association Studies (GWAS) Findings of Blood Cell Phenotypes

    PubMed Central

    Chami, Nathalie; Lettre, Guillaume

    2014-01-01

    Genome-wide association studies (GWAS) have identified reproducible genetic associations with hundreds of human diseases and traits. The vast majority of these associated single nucleotide polymorphisms (SNPs) are non-coding, highlighting the challenge in moving from genetic findings to mechanistic and functional insights. Nevertheless, large-scale (epi)genomic studies and bioinformatic analyses strongly suggest that GWAS hits are not randomly distributed in the genome but rather pinpoint specific biological pathways important for disease development or phenotypic variation. In this review, we focus on GWAS discoveries for the three main blood cell types: red blood cells, white blood cells and platelets. We summarize the knowledge gained from GWAS of these phenotypes and discuss their possible clinical implications for common (e.g., anemia) and rare (e.g., myeloproliferative neoplasms) human blood-related diseases. Finally, we argue that blood phenotypes are ideal to study the genetics of complex human traits because they are fully amenable to experimental testing. PMID:24705286

  2. White Blood Cell Count

    MedlinePlus

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

  3. Productive Infection of Human Peripheral Blood Mononuclear Cells by Feline Immunodeficiency Virus: Implications for Vector Development

    PubMed Central

    Johnston, James; Power, Christopher

    1999-01-01

    Feline immunodeficiency virus (FIV) is a lentivirus causing immune suppression and neurological disease in cats. Like primate lentiviruses, FIV utilizes the chemokine receptor CXCR4 for infection. In addition, FIV gene expression has been demonstrated in immortalized human cell lines. To investigate the extent and mechanism by which FIV infected primary and immortalized human cell lines, we compared the infectivity of two FIV strains, V1CSF and Petaluma, after cell-free infection. FIV genome was detected in infected human peripheral blood mononuclear cells (PBMC) and macrophages at 21 and 14 days postinfection, respectively. Flow cytometry analysis of FIV-infected human PBMC indicated that antibodies to FIV p24 recognized 12% of the cells. Antibodies binding the CCR3 chemokine receptor maximally inhibited infection of human PBMC by both FIV strains compared to antibodies to CXCR4 or CCR5. Reverse transcriptase levels increased in FIV-infected human PBMC, with detection of viral titers of 101.3 to 102.1 50% tissue culture infective doses/106 cells depending on the FIV strain examined. Cell death in human PBMC infected with either FIV strain was significantly elevated relative to uninfected control cultures. These findings indicate that FIV can productively infect primary human cell lines and that viral strain specificity should be considered in the development of an FIV vector for gene therapy. PMID:9971834

  4. Downstream effects of endocannabinoid on blood cells: implications for health and disease.

    PubMed

    Gasperi, Valeria; Evangelista, Daniela; Savini, Isabella; Del Principe, Domenico; Avigliano, Luciana; Maccarrone, Mauro; Catani, Maria Valeria

    2015-09-01

    Endocannabinoids (eCBs), among which N-arachidonoylethanolamine (AEA) and 2-arachidonoylglycerol (2-AG) are the most biologically active members, are polyunsaturated lipids able to bind cannabinoid, vanilloid and peroxisome proliferator-activated receptors. Depending on the target engaged, these bioactive mediators can regulate different signalling pathways, at both central and peripheral levels. The biological action of eCBs is tightly controlled by a plethora of metabolic enzymes which, together with the molecular targets of these substances, form the so-called "endocannabinoid system". The ability of eCBs to control manifold peripheral functions has received a great deal of attention, especially in the light of their widespread distribution in the body. In particular, eCBs are important regulators in blood, where they modulate haematopoiesis, platelet aggregation and apoptosis, as well as chemokine release and migration of immunocompetent cells. Here, we shall review the current knowledge on the pathophysiological roles of eCBs in blood. We shall also discuss the involvement of eCBs in those disorders affecting the haematological system, including cancer and inflammation. Knowledge gained to date underlines a fundamental role of the eCB system in blood, thus suggesting that it may represent a therapeutic promise for a broad range of diseases involving impaired hematopoietic cell functions. PMID:25957591

  5. 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

  6. Red blood cell production

    MedlinePlus Videos and Cool Tools

    ... or another. Red blood cells are an important element of blood. Their job is to transport oxygen ... hemocytoblasts give rise to all of the formed elements in blood. If a hemocytoblast commits to becoming ...

  7. 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.

  8. 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. PMID:21095146

  9. Red blood cell production

    MedlinePlus

    ... cells are an important element of blood. Their job is to transport oxygen to the body’s tissues in exchange for carbon dioxide, which is carried to and eliminated by the lungs. Red blood cells are formed in the red bone marrow of bones. Stem cells in the red bone marrow called hemocytoblasts ...

  10. Effects of exercise training on red blood cell production: implications for anemia.

    PubMed

    Hu, Min; Lin, Wentao

    2012-01-01

    Exercise training can increase total Hb and red cell mass, which enhances oxygen-carrying capacity. The possible underlying mechanisms are proposed to come mainly from bone marrow, including stimulated erythropoiesis with hyperplasia of the hematopoietic bone marrow, improvement of the hematopoietic microenvironment induced by exercise training, and hormone- and cytokine-accelerated erythropoiesis. Anemia is one of the most common medical conditions in chronic disease. The effects of exercise training on counteracting anemia have been explored and evaluated. The results of the research available to date are controversial, and it seems that significant methodological limitations exist. However, exercise training might be a promising, additional, safe and economical method to help improve anemia. There is a need for further investigation into the effects of and guidelines for exercise interventions (especially strength training) in this population of patients, particularly among cancer patients who are undergoing or have undergone chemotherapy or radiation treatments. As the available data are limited, additional research to uncover the underlying mechanisms associated with the effects of exercise training on anemia is clearly warranted. PMID:22301865

  11. 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.

  12. Red blood cells, sickle cell (image)

    MedlinePlus

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

  13. Red blood cells, sickle cell (image)

    MedlinePlus

    Sickle cell anemia 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 this photomicrograph.

  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. The impact of HIV-associated anaemia on the incidence of red blood cell transfusion: Implications for blood services in HIV-endemic countries

    PubMed Central

    van den Berg, Karin; Murphy, Edward L.; Pretorius, Lelanie; Louw, Vernon J.

    2015-01-01

    Cytopaenias, especially anaemia, are common in the HIV-infected population. The causes of HIV related cytopaenias are multi-factorial and often overlapping. In addition, many of the drugs used in the management of HIV-positive individuals are myelosuppresive and can both cause and exacerbate anaemia. Even though blood and blood products are still the cornerstone in the management of severe cytopaenias, how HIV may affect blood utilisation is not well understood. The impact of HIV/AIDS on blood collections has been well documented. As the threat posed by HIV on the safety of the blood supply became clearer, South Africa introduced progressively more stringent donor selection criteria, based on the HIV risk profile of the donor cohort from which the blood collected. The implementation of new testing technology in 2008 which significantly improved the safety of the blood supply enabled the removal of what was perceived by many as a racially based donor risk model. However, this new technology had a significant and sustained impact on the cost of blood and blood products in South Africa. In contrast, it would appear little is known of how HIV influences the utilisation of blood and blood products. Considering the high prevalence of HIV among hospitalised patients and the significant risk for anaemia among this group, there would be an expectation that the transfusion requirements of an HIV-infected patient would be higher than that of an HIV-negative patient. However, very little published data is available on this topic which emphasises the need for further large-scale studies to evaluate the impact of HIV/AIDS on the utilisation of blood and blood products and how the large-scale roll-out of ARV programs may in future play a role in determining the country’s blood needs. PMID:25457008

  16. 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.

  17. 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

  18. Blood transfusion: implications of treating a Jehovah's Witness patient.

    PubMed

    Effa-Heap, Gladys

    Jehovah's Witnesses believe that an individual's life is contained within blood, and that accepting transfusion of blood and blood products is sinful. The administration of blood to a Jehovah's Witness who has refused to accept transfusion may lead to criminal or civil proceedings. From an ethical viewpoint, if a rational adult who has been fully apprised of the consequences of not receiving this treatment persists in a refusal, the decision should be respected. Medical and nursing staff faced with such a problem should explore fully with the patient any transfusion alternatives that the patient might find acceptable, such as cell salvage, volume expanders, antifibrinolytics and pharmaceutical options, such as erythropoietin. This article examines the legal and consent issues around blood transfusion in Jehovah's Witness patients and their implications for medical and surgical management. PMID:19223803

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

    MedlinePlus

    ... 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.

  20. Cathepsin D: an Mϕ-derived factor mediating increased endothelial cell permeability with implications for alteration of the blood-retinal barrier in diabetic retinopathy.

    PubMed

    Monickaraj, Finny; McGuire, Paul G; Nitta, Carolina Franco; Ghosh, Kaustabh; Das, Arup

    2016-04-01

    Inflammation plays an important role in the pathogenesis of diabetic retinopathy (DR). We have previously reported increased monocyte (Mono) trafficking into the retinas of diabetic animals. In this study, we have examined the effect of activated Monos on retinal endothelial cells (ECs). The U937 Mϕ-conditioned medium (CM) significantly decreased the transendothelial resistance of EC monolayers as measured by electric cell-substrate impedance sensing (P= 0.007). The CM was fractioned, and the effective fraction (30-100 kDa) was analyzed by liquid chromatography-mass spectrometry, and cathepsin D (CD) was identified as a major secreted product. Immunoprecipitated CD resulted in decreased resistance in ECs (P= 0.006). The specificity of CD in mediating alterations of the EC barrier was confirmed using small interfering RNA. The decreased resistance correlated with a significantly increased gap between ECs. CD altered the Ras homolog gene family, member A/Rho-associated kinase pathway with increased stress actin filament formation in the EC layer. Increased CD levels were found in the retinas of diabetic mice (3-fold) and serum samples of patients with diabetic macular edema (1.6-fold) measured by Western blot and ELISA. These findings suggest an important role for Mϕ-derived CD in altering the blood-retinal barrier and reveal a potential therapeutic target in the treatment of DR.-Monickaraj, F., McGuire, P. G., Nitta, C. F., Ghosh, K., Das, A. Cathepsin D: an Mϕ-derived factor mediating increased endothelial cell permeability with implications for alteration of the blood-retinal barrier in diabetic retinopathy. PMID:26718887

  1. 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. PMID:24963818

  2. 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

  3. Red blood cells, sickle cells (image)

    MedlinePlus

    These crescent or sickle-shaped red blood cells (RBCs) are present with Sickle cell anemia, and stand out clearly against the normal round RBCs. These abnormally shaped cells may become entangled and ...

  4. Humoral Activity of Cord Blood-Derived Stem/Progenitor Cells: Implications for Stem Cell-Based Adjuvant Therapy of Neurodegenerative Disorders

    PubMed Central

    Paczkowska, Edyta; Kaczyńska, Katarzyna; Pius-Sadowska, Ewa; Rogińska, Dorota; Kawa, Miłosz; Ustianowski, Przemysław; Safranow, Krzysztof; Celewicz, Zbigniew; Machaliński, Bogusław

    2013-01-01

    Background Stem/progenitor cells (SPCs) demonstrate neuro-regenerative potential that is dependent upon their humoral activity by producing various trophic factors regulating cell migration, growth, and differentiation. Herein, we compared the expression of neurotrophins (NTs) and their receptors in specific umbilical cord blood (UCB) SPC populations, including lineage-negative, CD34+, and CD133+ cells, with that in unsorted, nucleated cells (NCs). Methods and Results The expression of NTs and their receptors was detected by QRT-PCR, western blotting, and immunofluorescent staining in UCB-derived SPC populations (i.e., NCs vs. lineage-negative, CD34+, and CD133+ cells). To better characterize, global gene expression profiles of SPCs were determined using genome-wide RNA microarray technology. Furthermore, the intracellular production of crucial neuro-regenerative NTs (i.e., BDNF and NT-3) was assessed in NCs and lineage-negative cells after incubation for 24, 48, and 72 h in both serum and serum-free conditions. We discovered significantly higher expression of NTs and NT receptors at both the mRNA and protein level in lineage-negative, CD34+, and CD133+ cells than in NCs. Global gene expression analysis revealed considerably higher expression of genes associated with the production and secretion of proteins, migration, proliferation, and differentiation in lineage-negative cells than in CD34+ or CD133+ cell populations. Notably, after short-term incubation under serum-free conditions, lineage-negative cells and NCs produced significantly higher amounts of BDNF and NT-3 than under steady-state conditions. Finally, conditioned medium (CM) from lineage-negative SPCs exerted a beneficial impact on neural cell survival and proliferation. Conclusions Collectively, our findings demonstrate that UCB-derived SPCs highly express NTs and their relevant receptors under steady-state conditions, NT expression is greater under stress-related conditions and that CM from SPCs

  5. Different forms of human vascular adhesion protein-1 (VAP-1) in blood vessels in vivo and in cultured endothelial cells: implications for lymphocyte-endothelial cell adhesion models.

    PubMed

    Salmi, M; Jalkanen, S

    1995-10-01

    Vascular endothelium plays a pivotal role in controlling leukocyte extravasation from the blood into the tissues. Vascular adhesion protein-1 (VAP-1) is a novel endothelial cell molecule which mediates lymphocyte binding to the vascular lining (Salmi, M., and Jalkanen, S., Science 1992. 257:1407). In this study, we analyzed endothelial cell type-specific differences of VAP-1. In vivo, VAP-1 is a 90/170-kDa molecule which is mainly expressed on the lumenal surface and in cytoplasmic granules of peripheral lymph node-type postcapillary venules (high endothelial venules, HEV). In tonsil HEV, VAP-1 is modified with abundant sialic acids. VAP-1 is also detectable in the cytoplasm of human umbilical vein endothelial cells (HUVEC) and in an endothelial cell hybrid EaHy-926, although both cell types lack detectable surface VAP-1. Cultured endothelial cells do not express MECA-79-defined peripheral lymph node addressins either. VAP-1 was not translocated onto the endothelial cell surface after stimulation with multiple cytokines, mitogens or secretagogues which induced expression of other known endothelial adhesion molecules. Biochemical analyses revealed that VAP-1 is a approximately 180-kDa protein in these endothelial cell types. Digestions with neuraminidase, O-glycanase and N-glycanase, as well as treatment of cells with tunicamycin and benzyl-N-acetylgalactosaminide, did not alter the molecular mass of VAP-1 in EaHy-926. Pulse-chase experiments showed that VAP-1 is directly synthesized as a 180-kDa molecule without any detectable precursors. Thus, in cultured endothelial cells, VAP-1 is a 180-kDa protein which is devoid of post-translational modifications, and in particular, lacks the sialic acids crucial for the function of VAP-1 in tonsil vessels. Notably, the endothelial cell types commonly used as a model in studying lymphocyte-endothelial cell interactions lack surface expression of VAP-1 and peripheral node addressins, and hence are inherently of limited use in

  6. 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.

  7. Lipopolysaccharide-induced early response genes in bovine peripheral blood mononuclear cells implicate GLG1/E-selectin as a key ligand–receptor interaction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study uses a systems biology approach, integrating global gene expression information and knowledge of the regulatory events in cells to identify transcription networks controlling peripheral blood mononuclear cells’ (PBMCs) immune response to lipopolysaccharide (LPS) and to identify the molecu...

  8. [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. PMID:25267201

  9. 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. PMID:26114426

  10. Deformability of Tumor Cells versus Blood Cells.

    PubMed

    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

  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. Red Blood Cell Antibody Identification

    MedlinePlus

    ... be limited. Home Visit Global Sites Search Help? RBC Antibody Identification Share this page: Was this page helpful? Also known as: Alloantibody Identification; Antibody ID, RBC; RBC Ab ID Formal name: Red Blood Cell ...

  13. Blood

    MedlinePlus

    ... solid part of your blood contains red blood cells, white blood cells, and platelets. Red blood cells (RBC) deliver oxygen from your lungs to your tissues and organs. White blood cells (WBC) fight infection and are part of your ...

  14. Blood cells and endothelial barrier function.

    PubMed

    Rodrigues, Stephen F; Granger, D Neil

    2015-01-01

    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

  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. Altered filtrability of white blood cells after myocardial infarction.

    PubMed

    Bogár, L; Mikita, J; Nash, G B; Smith, M J; Dormandy, J A; Tekeres, M

    1989-01-01

    Abnormal white blood cell rheological behaviour has been implicated as a cause of blood flow disturbances under conditions of ischaemia and reduced perfusion pressure. Accordingly, we have tested the mechanical properties of white cells following myocardial infarction by measuring the rate at which suspension of these cells cause plugging of Nuclepore filters. The number of clogging particles in a standard white cell suspension increased by the third day after infarction but subsequently decreased to the control levels. Since white cells can cause blockage of narrow blood vessels, it is assumed that such changes in cellular properties may influence the eventual extent of infarction. PMID:2812961

  17. 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. PMID:25128615

  18. Donating Peripheral Blood Stem Cells

    MedlinePlus

    ... Ways to give How your gift saves lives Donate cord blood Cord blood is changing lives Federal cord blood ... Cord blood options Sibling directed donation How to donate cord blood Participating hospitals Cord blood FAQs Learn if you ...

  19. Endurance Exercise Mobilizes Developmentally Early Stem Cells into Peripheral Blood and Increases Their Number in Bone Marrow: Implications for Tissue Regeneration.

    PubMed

    Marycz, Krzysztof; Mierzejewska, Katarzyna; Śmieszek, Agnieszka; Suszynska, Ewa; Malicka, Iwona; Kucia, Magda; Ratajczak, Mariusz Z

    2016-01-01

    Endurance exercise has been reported to increase the number of circulating hematopoietic stem/progenitor cells (HSPCs) in peripheral blood (PB) as well as in bone marrow (BM). We therefore became interested in whether endurance exercise has the same effect on very small embryonic-like stem cells (VSELs), which have been described as a population of developmentally early stem cells residing in BM. Mice were run daily for 1 hour on a treadmill for periods of 5 days or 5 weeks. Human volunteers had trained in long-distance running for one year, six times per week. FACS-based analyses and RT-PCR of murine and human VSELs and HSPCs from collected bone marrow and peripheral blood were performed. We observed that endurance exercise increased the number of VSELs circulating in PB and residing in BM. In parallel, we observed an increase in the number of HSPCs. These observations were subsequently confirmed in young athletes, who showed an increase in circulating VSELs and HSPCs after intensive running exercise. We provide for the first time evidence that endurance exercise may have beneficial effects on the expansion of developmentally early stem cells. We hypothesize that these circulating stem cells are involved in repairing minor exercise-related tissue and organ injuries. PMID:26664409

  20. 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.

  1. Blood flow and blood cell interactions and migration in microvessels

    NASA Astrophysics Data System (ADS)

    Fedosov, Dmitry; Fornleitner, Julia; Gompper, Gerhard

    2011-11-01

    Blood flow in microcirculation plays a fundamental role in a wide range of physiological processes and pathologies in the organism. To understand and, if necessary, manipulate the course of these processes it is essential to investigate blood flow under realistic conditions including deformability of blood cells, their interactions, and behavior in the complex microvascular network which is characteristic for the microcirculation. We employ the Dissipative Particle Dynamics method to model blood as a suspension of deformable cells represented by a viscoelastic spring-network which incorporates appropriate mechanical and rheological cell-membrane properties. Blood flow is investigated in idealized geometries. In particular, migration of blood cells and their distribution in blood flow are studied with respect to various conditions such as hematocrit, flow rate, red blood cell aggregation. Physical mechanisms which govern cell migration in microcirculation and, in particular, margination of white blood cells towards the vessel wall, will be discussed. In addition, we characterize blood flow dynamics and quantify hemodynamic resistance. D.F. acknowledges the Humboldt Foundation for financial support.

  2. Effects of changes in packed cell volume on the specific heat capacity of blood: implications for studies measuring heat exchange in extracorporeal circuits.

    PubMed

    Blake, A S; Petley, G W; Deakin, C D

    2000-01-01

    Extracorporeal circuits such as cardiopulmonary bypass (CPB) and renal dialysis machines cause active and/or passive loss of body heat. Attempts to quantify this heat loss are generally based on the Fick principle which requires knowledge of the specific heat capacity (SHC) of blood. As changes in packed cell volume are common, we investigated the effect of these changes on the SHC of blood over a range of packed cell volumes (PCV) from whole blood at 43.1% (3594 J kg-1 degrees C-1) to pure Hartmann's solution (4153 J kg-1 degrees C-1). The SHC of other fluids used during CPB was also measured and found to be 4139 J kg-1 degrees C-1 and 4082 J kg-1 degrees C-1 for normal saline and Gelofusine, respectively. The maximum variability in SHC over the range of PCV values encountered during CPB was calculated to be small (5.5%). We conclude that use of a constant value of SHC for calculation of thermal energy transfer is currently justified. PMID:10740543

  3. Biomaterials-Potential nucleation agents in blood and possible implications.

    PubMed

    Rohnke, Marcus; Henss, Anja

    2016-01-01

    Blood, simulated body fluids, and many cell culture media are supersaturated solutions with respect to several calcium phosphates. Therefore biomaterials can act as nucleation agents and evoke heterogeneous nucleation of salts on the surface of immersed biomaterials. Depending on the field of application, this can be either beneficial or disadvantageous. Although nucleation from supersaturated solutions is an old and well-known scientific phenomenon it is not standard to test new developed materials with surface analytical methods for their ability to initiate nucleation in vitro. Therefore, this communication aims to review the mineralization effect and to emphasize the possible negative implications, especially to functionalized bone implants. Surface coatings with proteins, growth factors, and, etc., can become ineffective due to deposition of a dense calcium phosphate layer. In the case of drug loaded implants, drug release might be inhibited. PMID:27316221

  4. ABO blood group and von Willebrand factor: biological implications.

    PubMed

    Franchini, Massimo; Crestani, Silvia; Frattini, Francesco; Sissa, Cinzia; Bonfanti, Carlo

    2014-09-01

    ABO blood group antigens are complex carbohydrate molecules expressed on the surface of red blood cells and a variety of human cells and tissues. It is well known that ABO blood type exerts a profound influence on hemostasis, being a major determinant of von Willebrand factor (VWF), and consequently factor VIII, plasma levels. In this review, we will focus on the molecular mechanisms underlying the interaction between ABO blood group and VWF in normal and pathological conditions. PMID:24945431

  5. 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.

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. Avoiding Anemia: Boost Your Red Blood Cells

    MedlinePlus

    ... link, please review our exit disclaimer . Subscribe Avoiding Anemia Boost Your Red Blood Cells If you’re ... and sluggish, you might have a condition called anemia. Anemia is a common blood disorder that many ...

  12. 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

  13. 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

  14. Alteration of red blood cell aggregation during blood storage

    NASA Astrophysics Data System (ADS)

    Lim, Hyun-Jung; Nam, Jeong-Hun; Lee, Byoung-Kwon; Suh, Jang-Soo; Shin, Sehyun

    2011-06-01

    Even though the trade-off between the benefits and risks of blood transfusion has been discussed for the last several decades, it requires further understanding of the rheological changes in stored blood that include the alteration of red blood cell (RBC) aggregation. The RBC aggregation of stored blood in its autologous plasma was monitored through the storage period (35 days). The critical shear stress, as a measure of RBC aggregation, was determined by using a microfluidic aggregometer. Blood was processed into a blood bag containing the anticoagulant CPDA1 and stored at 4°C. It was subjected to assays after zero, seven, 14, and 35 days. The critical shear stress for stored blood did not change up to 14 days of storage but exhibited a significant decrease after 35 days of storage. These results were identical to those of the conventional aggregation index (AI). Also, in the alteration of RBC aggregation for blood storage, the effect of the plasma factor was slightly stronger than that of the cellular factor. Through the present study, the critical shear stress as a new measure of RBC aggregation may help to monitor and control the quality of blood storage.

  15. 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...

  16. 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...

  17. 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...

  18. 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...

  19. MYELIN BASIC PROTEIN INDUCES INFLAMMATORY MEDIATORS FROM PRIMARY HUMAN ENDOTHELIAL CELLS AND BLOOD-BRAIN-BARRIER DISRUPTION: IMPLICATIONS FOR THE PATHOGENESIS OF MULTIPLE SCLEROSIS

    PubMed Central

    D’Aversa, Teresa G.; Eugenin, Eliseo A.; Lopez, Lillie; Berman, Joan W.

    2012-01-01

    Aim Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS), characterized by demyelination of white matter, loss of myelin forming oligodendrocytes, changes in the blood-brain-barrier (BBB), and leukocyte infiltration. Myelin basic protein (MBP) is a component of the myelin sheath. Degradation of myelin is believed to be an important step that leads to MS pathology. Transmigration of leukocytes across the vasculature, and a compromised BBB participate in the neuroinflammation of MS. We examined the expression and regulation of the chemokine CCL2 and the cytokine IL-6 in human endothelial cells (EC), a component of the BBB, after treatment with MBP. Methods EC were treated with full length MBP. CCL2 and IL-6 protein were determined by ELISA. Western blot analysis was used to determine signaling pathways. A BBB model was treated with MBP and permeability was assayed using albumin conjugated to Evan’s blue dye. The levels of the tight junction proteins occludin and claudin-1, and matrix metalloprotease (MMP)-2 were assayed by Western blot. Results MBP significantly induced CCL2 and IL-6 protein from EC. This induction was partially mediated by the p38 MAPK pathway as there was phosphorylation after MBP treatment. MBP treatment of a BBB model caused an increase in permeability that correlated with a decrease in occludin and claudin-1, and an induction of MMP-2. Conclusion These data demonstrate that MBP induces chemotactic and inflammatory mediators. MBP also alters BBB permeability and tight junction expression, indicating additional factors that may contribute to the BBB breakdown characteristic of MS. PMID:22524708

  20. 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. PMID:24983758

  1. 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.

  2. Blood

    MedlinePlus

    ... fight infection and are part of your body's defense system. Platelets help blood to clot when you have a cut or wound. Bone marrow, the spongy material inside your bones, makes new blood cells. Blood cells ...

  3. Clinical Implications of Ambulatory and Home Blood Pressure Monitoring

    PubMed Central

    2010-01-01

    Because blood pressure (BP) is an ever changing hemodynamic phenomenon, a BP value, once measured at a physician's office (Office BP), is often unrepresentative of an individual's true BP status. Both ambulatory blood pressure monitoring (ABPM) and home blood pressure monitoring (HBPM) provide more accurate and reproducible estimate of BP, and produce stronger predictive ability for cardiovascular outcome than conventional office BP. Two BP measuring techniques, ABPM and HBPM have been widely in clinical use for the detection and management of hypertension. However, they have different advantages and limitations in practice. At present, it has become crucial to understand the characteristics and clinical implications of these BP measuring techniques for those responsible for the care of hypertensive patients. PMID:20967142

  4. 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

  5. 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.

  6. 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. PMID:25676375

  7. 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 ...

  8. 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 ...

  9. 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.

  10. Autophagy in blood cancers: biological role and therapeutic implications

    PubMed Central

    Nencioni, Alessio; Cea, Michele; Montecucco, Fabrizio; Longo, Valter D.; Patrone, Franco; Carella, Angelo M.; Holyoake, Tessa L.; Helgason, G. Vignir

    2013-01-01

    Autophagy is a cell recycling process the molecular apparatus of which has been identified over the past decade. Autophagy allows cells to survive starvation and inhospitable conditions and plays a key role in numerous physiological functions, including hematopoiesis and immune responses. In hematologic malignancies, autophagy can either act as a chemo-resistance mechanism or have tumor suppressive functions, depending on the context. In addition, autophagy is involved in other important aspects of blood cancers as it promotes immune competence and anti-cancer immunity, and may even help enhance patient tolerance to standard treatments. Approaches exploiting autophagy, either to activate or inhibit it, could find broad application in hematologic malignancies and contribute to improved clinical outcomes. These aspects are discussed here together with a brief introduction to the molecular machinery of autophagy and to its role in blood cell physiology. PMID:24006406

  11. 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... 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...

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. 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...

  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...

  18. 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...

  19. 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...

  20. 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...

  1. When Blood Cells Bend: Understanding Sickle Cell Disease

    MedlinePlus

    ... oxygen. This medical emergency, called a sickle cell crisis, can be treated with pain medication and blood ... Although the treatment of sickle cell disease pain crisis hasn’t changed much since the discovery of ...

  2. Viscoelastic transient of confined red blood cells.

    PubMed

    Prado, Gaël; Farutin, Alexander; Misbah, Chaouqi; Bureau, Lionel

    2015-05-01

    The unique ability of a red blood cell to flow through extremely small microcapillaries depends on the viscoelastic properties of its membrane. Here, we study in vitro the response time upon flow startup exhibited by red blood cells confined into microchannels. We show that the characteristic transient time depends on the imposed flow strength, and that such a dependence gives access to both the effective viscosity and the elastic modulus controlling the temporal response of red cells. A simple theoretical analysis of our experimental data, validated by numerical simulations, further allows us to compute an estimate for the two-dimensional membrane viscosity of red blood cells, η(mem)(2D) ∼ 10(-7) N ⋅ s ⋅ m(-1). By comparing our results with those from previous studies, we discuss and clarify the origin of the discrepancies found in the literature regarding the determination of η(mem)(2D), and reconcile seemingly conflicting conclusions from previous works. PMID:25954871

  3. 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.

  4. Blood flow and arterial endothelial dysfunction: Mechanisms and implications

    NASA Astrophysics Data System (ADS)

    Barakat, Abdul I.

    2013-06-01

    The arterial endothelium exquisitely regulates vascular function, and endothelial dysfunction plays a critical role in the development of atherosclerosis. Atherosclerotic lesions develop preferentially at arterial branches and bifurcations where the blood flow is disturbed. Understanding the basis for this observation requires elucidating the effects of blood flow on the endothelial cell (EC) function. The goal of this review is: (1) to describe our current understanding of the relationships between arterial blood flow and atherosclerosis, (2) to present the wide array of flow-induced biological responses in ECs, and (3) to discuss the mechanisms by which ECs sense, transmit, and transduce flow-derived mechanical forces. We conclude by presenting some future perspectives in the highly interdisciplinary field of EC mechanotransduction.

  5. 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.

  6. Red blood cell transfusion in newborn infants.

    PubMed

    Whyte, Robin K; Jefferies, Ann L

    2014-04-01

    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

  7. "Blood failure" time to view blood as an organ: how oxygen debt contributes to blood failure and its implications for remote damage control resuscitation.

    PubMed

    Bjerkvig, Christopher K; Strandenes, Geir; Eliassen, Håkon S; Spinella, Philip C; Fosse, Theodor K; Cap, Andrew P; Ward, Kevin R

    2016-04-01

    Hemorrhagic shock is both a local and systemic disorder. In the context of systemic effects, blood loss may lead to levels of reduced oxygen delivery (DO2 ) sufficient to cause tissue ischemia. Similar to other physiologic debts such as sleep, it is not possible to incur a significant oxygen debt and suffer no consequences for lack of timely repayment. While the linkage between oxygen debt and traditional organ failure (renal, hepatic, lung, and circulation) has been long recognized, we should consider failure in two additional linked and very dynamic organ systems, the endothelium and blood. These systems are very sensitive to oxygen debt and at risk for failing, having further implications on all other organ systems. The degree of damage to the endothelium is largely modulated by the degree of oxygen debt. Thus hypoperfusion is believed to begin a cascade of events leading to acute traumatic coagulopathy (ATC). This combination of oxygen debt driven endothelial damage and ATC might be considered collectively as "blood failure" due to the highly connected networks between these drivers. This article presents the implications of oxygen debt for remote damage control resuscitation strategies, such as permissive hypotension and hemostatic resuscitation. We review the impact of whole blood resuscitation and red blood cell efficacy in mitigation of oxygen debt. At last, this article recognizes the need for simple and durable, lightweight equipment that can detect the adequacy of tissue DO2 and thus patient needs for resuscitative care. Point-of-care lactate measuring may be a predictive tool for identifying high-risk trauma patients and occult shock because it provides information beyond that of vital signs and mechanism of injury as it may help predict the level of oxygen debt accumulation and need for resuscitation. Serial measurements may also be valuable as a tool in guiding resuscitative efforts. PMID:27100755

  8. 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.

  9. 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.

  10. 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.

  11. P2X and P2Y receptor signaling in red blood cells

    PubMed Central

    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. PMID:26579528

  12. Thrombosis and blood cells in atherosclerosis development.

    PubMed

    Santolaya, C; Hernández, M R; Villaverde, C A

    1988-06-01

    Hemorheological changes produced in blood cells seem to be essential in atheroma plaque development and thrombotic episodes. In this study, we investigated the relationship between blood cells count, thrombogenic situations and morphological mesenteric alterations in atherosclerotic rats. Atherosclerosis was induced by an atherogenic diet made up of two phases, the first a hypervitaminic diet, and the second a hyperlipidic one. Cell counts were performed with Thoma's camera. Morphological changes were observed directly in rat mesentery. Thrombogenic situations were investigated by a mesenteric microthrombosis induction method. In atherosclerotic animals we can observe a higher mesenteric opacity, increase in blood viscosity and a thickness in vessel wall. Thrombosis time is shortened at 3 days, which indicates a thrombogenic situation although at 10 days there is a lenthening in this parameter. Blood cell counts were not modified significantly, but modifications in differential leukocyte counts were significant. We found a direct relationship between lymphocyte number and thrombosis time whereas with granulocytes this relationship was inverse: shortening in thrombosis time appearing simultaneously with an increase in cell number. PMID:3419397

  13. Tissue engineering red blood cells: a therapeutic.

    PubMed

    van Veen, Theun; Hunt, John A

    2015-07-01

    The use of red blood cells (RBCs) in transfusion is widespread in modern medicine. Limitations in blood transfusion have made an urgent argument for the focus on alternatives, as particular medical treatments heavily rely on the supply of donated blood. Stem cells have been successfully used in vitro to produce RBCs and researchers are currently challenged with developing larger-scale culture methods to meet the requirements for clinically relevant cell numbers. The ultimate conditions that will be beneficial for this type of research are trivial. A successful human clinical trial has shown that tremendous progress has already been made in this field. Other alternatives are based on the oxygen carrier protein that RBCs contain, i.e. haemoglobin (Hb). Chemically defined molecules and crosslinked proteins, which are able to bind and transport oxygen, have been found to be functional in vivo. Major progress has been achieved, but developing highly suitable products for the transfusion market still remains an enormous challenge for these acellular blood substitutes. We provide a review about developing alternatives for blood transfusion, with the emphasis on tissue-engineering approaches. PMID:24753354

  14. Dielectrophoretic Separation of Cancer Cells from Blood

    PubMed Central

    Gascoyne, Peter R. C.; Wang, Xiao-Bo; Huang, Ying; Becker, Frederick F.

    2009-01-01

    Recent measurements have demonstrated that the dielectric properties of cells depend on their type and physiological status. For example, MDA-231 human breast cancer cells were found to have a mean plasma membrane specific capacitance of 26 mF/m2, more than double the value (11 mF/m2) observed for resting T-lymphocytes. When an inhomogeneous ac electric field is applied to a particle, a dielectrophoretic (DEP) force arises that depends on the particle dielectric properties. Therefore, cells having different dielectric characteristics will experience differential DEP forces when subjected to such a field. In this article, we demonstrate the use of differential DEP forces for the separation of several different cancerous cell types from blood in a dielectric affinity column. These separations were accomplished using thin, flat chambers having microelectrode arrays on the bottom wall. DEP forces generated by the application of ac fields to the electrodes were used to influence the rate of elution of cells from the chamber by hydrodynamic forces within a parabolic fluid flow profile. Electrorotation measurements were first made on the various cell types found within cell mixtures to be separated, and theoretical modeling was used to derive the cell dielectric parameters. Optimum separation conditions were then predicted from the frequency and suspension conductivity dependencies of cell DEP responses defined by these parameters. Cell separations were then undertaken for various ratios of cancerous to normal cells at different concentrations. Eluted cells were characterized in terms of separation efficiency, cell viability, and separation speed. For example, 100% efficiency was achieved for purging MDA-231 cells from blood at the tumor to normal cell ratio 1:1 × 105 or 1:3 × 105, cell viability was not compromised, and separation rates were at least 103 cells/s. Theoretical and experimental criteria for the design and operation of such separators are presented. PMID

  15. 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. PMID:26773879

  16. [Blast cells in peripheral blood smear].

    PubMed

    Lüthi, U; Huber, A R

    2004-02-01

    Despite modern technologies such as immunophenotyping and molecular probing cytomorphological examination of stained peripheral blood smears by microscopy remains the mainstay of diagnosis in a large variety of diseases. Although technically simple morphological analysis requires considerable skill. Early diagnosis in several hematological diseases is important (for example acute promyelocytic leukaemia associated frequently with disseminated intravascular coagulation), in order to initiate adjusted therapy. Further, referral of the patient to tertiary care centers is only justified after a solid diagnosis is obtained. Many disorders can be diagnosed by pathognomonic blood smears. The present article is a short overview of important hematological disorders, which are associated with blast cells in the peripheral blood. Important morphological cell characteristics are illustrated by microscopic pictures. PMID:15018395

  17. Red blood cell membrane defects.

    PubMed

    Iolascon, Achille; Perrotta, Silverio; Stewart, Gordon W

    2003-03-01

    We present an overview of the currently known molecular basis of red cell membrane disorders. A detailed discussion of the structure of the red cell membrane and the pathophysiology and clinical aspects of its disorders is reported. Generally speaking, hereditary spherocytosis (HS) results from a loss of erythrocyte surface area. The mutations of most cases of HS are located in the following genes: ANK1, SPTB, SLC4A1, EPB42 and SPTA1, which encode for ankyrin, spectrin beta-chain, the anion exchanger 1 (band 3), protein 4.2 and spectrin alpha-chain, respectively. Hereditary elliptocytosis (HE) reflects a diminished elasticity of the skeleton. Its aggravated form, hereditary pyropoikilocytosis (HPP), implies that the skeleton undergoes further destabilization. The mutations responsible for HE and HPP, lie in the SPTA1 and SPTB gene, and in the EPB41 gene encoding protein 4.1. Allele alpha LELY is a common polymorphic allele, which plays the role of an aggravating factor when it occurs in trans of an elliptocytogenic allele of the SPTA1 gene. Southeast Asian ovalocytosis derives from a change in band 3. The genetic disorders of membrane permeability to monovalent cations required a positional cloning approach. In this respect, channelopathies represent a new frontier in the field. Dehydrated hereditary stomatocytosis (DHS) was shown to belong to a pleiotropic syndrome: DHS + fetal edema + pseudohyperkalemia, which maps 16q23-24. Splenectomy is strictly contraindicated in DHS and another disease of the same class, overhydrated hereditary stomatocytosis, because it increases the risk of thromboembolic accidents. PMID:14692233

  18. 21 CFR 660.30 - Reagent Red Blood Cells.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... identify human blood-group antibodies. (b) Source. Reagent Red Blood Cells shall be prepared from human... 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 §...

  19. 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.

  20. Repository of Human Blood Derivative Biospecimens in Biobank: Technical Implications

    PubMed Central

    Mohamadkhani, Ashraf; Poustchi, Hossein

    2015-01-01

    Human biorepositories are collection of biological samples and health information from a large number of participants generally in the cohort studies. The main purpose of established biobanks is organization of biomedical research for upgrading the knowledge of human disorders from cancer to infectious and rare disease. The studies of generation relationships and understanding the preclinical stages of ageing are also from the solution of bitobank. This review overview the significance and storage condition of biospecimens including whole blood, red blood cells (RBC), buffy coat, plasma, serum, DNA and RNA that derived from blood in human biobanks. These biological samples provide valuable information on the prevalence of germline mutations, epigenetic modifications or interaction between genes and proteins in associated with the development of certain types of disease. The quality of biospecimen in biobanks is a powerful tool for valid identification of biomarkers. Therefore optimum qualities of human biological samples in long time storage that have been assessed in several studies also indicate in this review. PMID:26106464

  1. 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. PMID:26096663

  2. 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.

  3. 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.

  4. 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.

  5. 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.”

  6. 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

  7. Viscoelastic Transient of Confined Red Blood Cells

    PubMed Central

    Prado, Gaël; Farutin, Alexander; Misbah, Chaouqi; Bureau, Lionel

    2015-01-01

    The unique ability of a red blood cell to flow through extremely small microcapillaries depends on the viscoelastic properties of its membrane. Here, we study in vitro the response time upon flow startup exhibited by red blood cells confined into microchannels. We show that the characteristic transient time depends on the imposed flow strength, and that such a dependence gives access to both the effective viscosity and the elastic modulus controlling the temporal response of red cells. A simple theoretical analysis of our experimental data, validated by numerical simulations, further allows us to compute an estimate for the two-dimensional membrane viscosity of red blood cells, ηmem2D ∼ 10−7 N⋅s⋅m−1. By comparing our results with those from previous studies, we discuss and clarify the origin of the discrepancies found in the literature regarding the determination of ηmem2D, and reconcile seemingly conflicting conclusions from previous works. PMID:25954871

  8. Responder individuality in red blood cell alloimmunization.

    PubMed

    Körmöczi, Günther F; Mayr, Wolfgang R

    2014-11-01

    Many different factors influence the propensity of transfusion recipients and pregnant women to form red blood cell alloantibodies (RBCA). RBCA may cause hemolytic transfusion reactions, hemolytic disease of the fetus and newborn and may be a complication in transplantation medicine. Antigenic differences between responder and foreign erythrocytes may lead to such an immune answer, in part with suspected specific HLA class II associations. Biochemical and conformational characteristics of red blood cell (RBC) antigens, their dose (number of transfusions and pregnancies, absolute number of antigens per RBC) and the mode of exposure impact on RBCA rates. In addition, individual circumstances determine the risk to form RBCA. Responder individuality in terms of age, sex, severity of underlying disease, disease- or therapy-induced immunosuppression and inflammation are discussed with respect to influencing RBC alloimmunization. For particular high-risk patients, extended phenotype matching of transfusion and recipient efficiently decreases RBCA induction and associated clinical risks. PMID:25670932

  9. Perivascular cells in blood vessel regeneration.

    PubMed

    Wanjare, Maureen; Kusuma, Sravanti; Gerecht, Sharon

    2013-04-01

    Vascular engineering seeks to design and construct functional blood vessels comprising endothelial cells (ECs) and perivascular cells (PCs), with the ultimate goal of clinical translation. While EC behavior has been extensively investigated, PCs play an equally significant role in the development of novel regenerative strategies, providing functionality and stability to vessels. The two major classes of PCs are vascular smooth muscle cells (vSMCs) and pericytes; vSMCs can be further sub-classified as either contractile or synthetic. The inclusion of these cell types is crucial for successful regeneration of blood vessels. Furthermore, understanding distinctions between vSMCs and pericytes will enable improved therapeutics in a tissue-specific manner. Here we focus on the approaches and challenges facing the use of PCs in vascular regeneration, including their characteristics, stem cell sources, and interactions with ECs. Finally, we discuss biochemical and microRNA (miR) regulators of PC behavior and engineering approaches that mimic various cues affecting PC function. PMID:23554249

  10. 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. PMID:26071649

  11. 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.

  12. 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... enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in... kinase or 2,3-diphosphoglycerate. A red blood cell enzyme assay is used to determine the enzyme...

  13. 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... enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in... kinase or 2,3-diphosphoglycerate. A red blood cell enzyme assay is used to determine the enzyme...

  14. 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... enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in... kinase or 2,3-diphosphoglycerate. A red blood cell enzyme assay is used to determine the enzyme...

  15. 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... enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in... kinase or 2,3-diphosphoglycerate. A red blood cell enzyme assay is used to determine the enzyme...

  16. 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... enzyme assay. (a) Identification. Red blood cell enzyme assay is a device used to measure the activity in... kinase or 2,3-diphosphoglycerate. A red blood cell enzyme assay is used to determine the enzyme...

  17. 21 CFR 864.6160 - Manual blood cell counting device.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Manual blood cell counting device. 864.6160... (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Manual Hematology Devices § 864.6160 Manual blood cell counting device. (a) Identification. A manual blood cell counting device is a device used...

  18. 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...

  19. 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...

  20. 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...

  1. 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...

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. 21 CFR 864.5240 - Automated blood cell diluting apparatus.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 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...

  7. 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.

  8. Red blood cell in simple shear flow

    NASA Astrophysics Data System (ADS)

    Chien, Wei; Hew, Yayu; Chen, Yeng-Long

    2013-03-01

    The dynamics of red blood cells (RBC) in blood flow is critical for oxygen transport, and it also influences inflammation (white blood cells), thrombosis (platelets), and circulatory tumor migration. The physical properties of a RBC can be captured by modeling RBC as lipid membrane linked to a cytoskeletal spectrin network that encapsulates cytoplasm rich in hemoglobin, with bi-concave equilibrium shape. Depending on the shear force, RBC elasticity, membrane viscosity, and cytoplasm viscosity, RBC can undergo tumbling, tank-treading, or oscillatory motion. We investigate the dynamic state diagram of RBC in shear and pressure-driven flow using a combined immersed boundary-lattice Boltzmann method with a multi-scale RBC model that accurately captures the experimentally established RBC force-deformation relation. It is found that the tumbling (TU) to tank-treading (TT) transition occurs as shear rate increases for cytoplasm/outer fluid viscosity ratio smaller than 0.67. The TU frequency is found to be half of the TT frequency, in agreement with experiment observations. Larger viscosity ratios lead to the disappearance of stable TT phase and unstable complex dynamics, including the oscillation of the symmetry axis of the bi-concave shape perpendicular to the flow direction. The dependence on RBC bending rigidity, shear modulus, the order of membrane spectrin network and fluid field in the unstable region will also be discussed.

  9. 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.

  10. 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

  11. 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.

  12. Single-cell measurement of red blood cell oxygen affinity

    PubMed Central

    Di Caprio, Giuseppe; Stokes, Chris; Higgins, John M.; Schonbrun, Ethan

    2015-01-01

    Oxygen is transported throughout the body by hemoglobin (Hb) in red blood cells (RBCs). Although the oxygen affinity of blood is well-understood and routinely assessed in patients by pulse oximetry, variability at the single-cell level has not been previously measured. In contrast, single-cell measurements of RBC volume and Hb concentration are taken millions of times per day by clinical hematology analyzers, and they are important factors in determining the health of the hematologic system. To better understand the variability and determinants of oxygen affinity on a cellular level, we have developed a system that quantifies the oxygen saturation, cell volume, and Hb concentration for individual RBCs in high throughput. We find that the variability in single-cell saturation peaks at an oxygen partial pressure of 2.9%, which corresponds to the maximum slope of the oxygen–Hb dissociation curve. In addition, single-cell oxygen affinity is positively correlated with Hb concentration but independent of osmolarity, which suggests variation in the Hb to 2,3-diphosphoglycerate (2–3 DPG) ratio on a cellular level. By quantifying the functional behavior of a cellular population, our system adds a dimension to blood cell analysis and other measurements of single-cell variability. PMID:26216973

  13. Migration of blood cells to β-amyloid plaques in Alzheimer’s disease

    PubMed Central

    Hohsfield, Lindsay A.; Humpel, Christian

    2015-01-01

    Alzheimer’s disease (AD) is a neurodegenerative disease that leads to the progressive deterioration of cognitive and memory functions. The deposition of extracellular beta-amyloid (Aβ) senile plaques and intracellular tau neurofibrillary tangles are considered the cardinal pathological hallmarks of AD, however, accumulating evidence indicates that immune cells may also play an important role in disease pathogenesis. Among these immune cells, blood-derived cells and their infiltration into the CNS towards Aβ plaques have been implicated in therapeutic strategies against AD. Here, we review the current literature on blood cell migration into the AD brain and the important players involved in this selective migration towards Aβ plaques. PMID:25752742

  14. 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. PMID:27252101

  15. 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.

  16. Dielectric Constant of Suspensions of Blood Cells

    NASA Astrophysics Data System (ADS)

    Mendelson, Kenneth; Ackmann, James

    1996-03-01

    Measurements of the complex dielectric constant of suspensions of blood cells have recently been reported by Ackmann, et al.(J. J. Ackmann, et al., Ann. Biomed. Eng. 24), 58 (1996). At frequencies below 100 kHz, the real part of the dielectric constant (ɛ') goes through a maximum at a blood cell volume fraction of about 70%. Effective medium approximations do not agree well with this behavior. As a more realistic model, we are studying the grain consolidation model of Roberts and Schwartz(J. N. Roberts and L. M. Schwartz, Phys. Rev. B 31), 5990 (1985). We have used a finite element method to calculate the dielectric constant of this model for a cubic array of spheres. The simulations agree remarkably well with experiment. They suggest, however, that ɛ' may be showing oscillations rather than a simple maximum. Comparison of the simulated and experimental points suggests that this is not an artifact of the periodic array used in the model. Furthermore the simulations indicate that the maximum (or oscillations) disappears at low conductivities of the suspending fluid.

  17. Photoacoustic assessment of oxygen saturation: effect of red blood cell aggregation

    NASA Astrophysics Data System (ADS)

    Hysi, Eno; Saha, Ratan K.; Kolios, Michael C.

    2013-03-01

    The simultaneous photoacoustic assessment of oxygen saturation and red blood cell aggregation is presented. Aggregation was induced on porcine red blood cells using Dextran-70 at multiple hematocrit levels. Samples were exposed to 750 nm and 1064 nm for each hematocrit and aggregate size in order to compute the oxygen saturation. As the size of the aggregate increased, the photoacoustic signal amplitude increased monotonically. The same trend was observed for increasing hematocrit at each aggregation level. The oxygen saturation of aggregated samples was 30% higher than non-aggregated samples at each hematocrit level. This suggests that the presence of red blood cell aggregates impairs the release of oxygen to the surrounding environment. Such a result has important implications for detecting red blood cell aggregation non-invasively and making clinical decisions based on the simulatenous assessment of oxygen saturation.

  18. T-cell homeostasis: implications in HIV infection .

    PubMed

    Adleman, L M; Wofsy, D

    1993-02-01

    Evidence is presented that a homeostatic mechanism exists that maintains a normal T-cell count, but is unresponsive to abnormalities in CD4+ T-cell count and CD8+ T-cell count. Specifically, we hypothesize that in all cases of T-cell loss, whether selective or not, both CD4+ T cells and CD8+ T cells will be produced until the absolute T-cell count returns to normal, even if this produces or exacerbates abnormalities in the absolute CD4+ T-cell count and absolute CD8+ T-cell count. This hypothesis implies that the selective loss of CD4+ T cells will induce the production of both CD4+ T cells and CD8+ T cells with the result that T-cell count will return to normal, but a persistent CD8+ T-cell lymphocytosis and CD4+ T-cell lymphopenia will be produced. To test this hypothesis, we monitored T-cell reconstitution in mice selectively depleted of CD4+ T cells through treatment with a CD4-specific monoclonal antibody (mAb). Consistent with our hypothesis, the absolute peripheral blood T-cell count in treated mice returned to that of controls after approximately 4 months. However, the absolute CD8+ cell count became 163% of controls and the absolute CD4+ cell count remained less than 63% of controls. Our hypothesis may have implications regarding the pathogenesis and treatment of human immunodeficiency virus (HIV) infection. In particular, the hypothesis implies that the unresolved CD4+ T-cell lymphopenia seen in the first several years of HIV infection is the "natural" consequence of the interaction of a selective CD4+ T-cell depleting virus and a nonselective T-cell replacing homeostatic mechanism.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8094457

  19. 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. PMID:26450984

  20. Cord blood stem cells - a dream for future medicine.

    PubMed

    Chakraborty, S K; Banu, L A; Rahman, M F; Paul, S

    2014-07-01

    Umbilical cord blood collected at birth is a rich source of stem cells that can be used to treat diseases of the blood and immune system. Cord blood stem cells which have infinite medical potential are currently used in the treatment of several life-threatening diseases, and play an important role in the treatment of blood and immune system related genetic diseases, cancers, and blood disorders. Transplant recipients are less likely to reject a cord blood stem cell and do not require a perfect match as bone marrow transplants do. Transplantation of umbilical cord blood stem cells represents a major advantage in providing a new source of stem cells to patients in need. Private storage of cord blood stem cells clearly has value, in that it provides future patients and families with potential therapeutic options for transplant. Many recent studies showed that human umbilical cord blood stem cells have the potential to generate cells with neuronal characteristics. Therefore, the umbilical cord blood stem cells can be viewed as the stem cells source of choice for clinical and non-clinical research applications. PMID:25178624

  1. 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

  2. Perturbation of red blood cell flow in small tubes by white blood cells.

    PubMed

    Thompson, T N; La Celle, P L; Cokelet, G R

    1989-02-01

    The flow of blood in the microcirculation is facilitated by the dynamic reduction in viscosity (Fahraeus-Lindquist effect) resulting from the axial flow of deforming erythrocytes (RBCs) and from the decrease in the ratio of cell to vessel diameter. RBC velocity exceeds that of average fluid velocity; however the slower moving white blood cells (WBC) perturb flow velocity and the ratio of cell to vessel diameter by obstructing red cell flow through formation of "trains" of red cells collecting behind the white cell. This effect of white cells was studied quantitatively in a model in vitro tubes less than 10 microns in diameter with the demonstration that flow resistance increases linearly with white cell numbers up to 1,000 WBC/mm3 at tube hematocrit of 17.7%. The increase in resistance exceeds the flow resistance of WBC and appears to relate directly to train formation. A mechanical model of train formation developed to predict WBC influence in flow resistance over the range of WBC studied reasonably fits observed WBC effects. PMID:2928089

  3. 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.

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

    PubMed Central

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

    2016-01-01

    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. PMID:26590403

  5. 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.

  6. Blood donor behaviour in Greece: implications for health policy.

    PubMed

    Chliaoutakis, J; Trakas, D J; Socrataki, F; Lemonidou, C; Papaioannou, D

    1994-05-01

    Blood donation behaviour was studied in 809 residents of the Greater Athens area to identify socio-economic and attitudinal factors and level of knowledge about blood donation related to donor behaviour. The sample was randomly selected and consisted of men and women aged 18-65, the legally defined age for donation. According to stepwise regression analysis, blood donation (40.8% of the study population) was found to be correlated with gender, place of birth, occupation and knowledge about donation. Donors were more likely to be men than women; students and military recruits than professionals and scientists; and those with higher knowledge scores regarding donation. In our factor analysis of the social attitudes related to blood donation, three factors emerged as important regarding donation: health-related incentives for the donor, structural incentives (organization of blood donation education and management of facilities) and the creation of social and economic incentives. With respect to the affective measures those who expressed feelings of guilt when presented with hypothetical, emotionally charged situations dramatizing the need for donor blood were more likely to be donors. The results of the data are discussed within a larger socio-cultural context and suggestions for health policy are made. PMID:8023195

  7. Pituitary stem cells: candidates and implications.

    PubMed

    Nassiri, Farshad; Cusimano, Michael; Zuccato, Jeff A; Mohammed, Safraz; Rotondo, Fabio; Horvath, Eva; Syro, Luis V; Kovacs, Kalman; Lloyd, Ricardo V

    2013-09-01

    The pituitary is the master endocrine gland of the body. It undergoes many changes after birth, and these changes may be mediated by the differentiation of pituitary stem cells. Stem cells in any tissue source must display (1) pluripotent capacity, (2) capacity for indefinite self-renewal, and (3) a lack of specialization. Unlike neural stem cells identified in the hippocampus and subventricular zone, pituitary stem cells are not associated with one specific cell type. There are many major candidates that are thought to be potential pituitary stem cell sources. This article reviews the evidence for each of the major cell types and discuss the implications of identifying a definitive pituitary stem cell type. PMID:23423660

  8. 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.

  9. 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.

  10. 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

  11. 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

  12. 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.

  13. White blood cell count - series (image)

    MedlinePlus

    ... puncture site is cleaned with antiseptic, and a tourniquet (an elastic band) or blood pressure cuff is ... through the vein. This causes veins below the tourniquet to distend (fill with blood). A needle is ...

  14. 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

  15. 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.

  16. 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

  17. Cutaneous microcirculation and blood rheology following cardiopulmonary bypass. Laser Doppler flowmetric and blood cell rheologic studies.

    PubMed

    al-Khaja, N; Belboul, A; Bergman, P; Roberts, D; William-Olsson, G

    1988-01-01

    In 23 patients undergoing coronary artery bypass grafting, measurements of cutaneous blood flow were made with laser doppler flowmetry. Simultaneously blood was sampled for measurement of red cell filtration rate (RFR) and plasma-white cell filtration rate (P-WFR). The cutaneous blood flow showed significant overall reduction postoperatively. When the saphenous vein or internal mammary artery was used as bypass graft, the reduction in skin blood flow at the sites from which the vessels were taken was significantly greater than in contralateral, undisturbed sites. RFR and P-WFR were also significantly reduced postoperatively, and these changes showed significant concomitance with the fall in laser doppler flow (LDF%). On postoperative day 6 there was some improvement in LDF% and RFR but further slight deterioration in P-WFR. The study indicated that surgical trauma locally reduces cutaneous blood flow and that trauma to blood cells following cardiopulmonary bypass can contribute to this reduction. PMID:2970114

  18. 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

  19. 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

  20. Enrichment of fetal nucleated cells from maternal blood: model test system using cord blood.

    PubMed

    Andrews, K; Wienberg, J; Ferguson-Smith, M A; Rubinsztein, D C

    1995-10-01

    The presence of small numbers of fetal nucleated red cells in the maternal circulation has been a stimulus for the development of technologies for non-invasive prenatal genetic analysis. Our laboratory has been assessing the feasibility of density gradient centrifugation followed by magnetic activated cell sorting (MACS) of cells expressing CD32 and CD45, to deplete maternal nucleated blood cells. We have examined the efficiency of each of the steps of this procedure using cord blood from term pregnancies as a source of nucleated red blood cells. Cord blood was shown to contain highly variable numbers of nucleated red cells. Three different density gradients were examined. There was no major difference in the performances of the double and triple gradients. Density gradient centrifugation resulted in enrichments of nucleated red blood cells of about 1000-fold relative to the total cell count. However, it was apparent that the selection of the cell layers which were most enriched for these cells would result in significant losses of nucleated red cells in other layers. MACS sorting of cells using CD45 resulted in white cell depletions ranging from 7 to 34-fold. These data provide a foundation for comparison with other methods and for optimization of the MACS technique. PMID:8587859

  1. 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

  2. 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.

  3. [Stem cells of umbilical blood cord - therapeutic use].

    PubMed

    Bielec, Beata; Stojko, Rafał

    2015-01-01

    For many years, the transplantation of hematopoietic stem cells has been used to treat some diseases of the hematopoietic system. For a very long time, only bone marrow was used as a source of hematopoietic stem cells for this method of treatment. However, to comply with allogeneic bone marrow transplantation, an antigenically compatible donor is necessary. Transplantations from unrelated donors are associated with increased risk of a graft-versus-host reaction, transplant rejection and, consequently, increased mortality. Many years ago, it was found that umbilical cord blood as well as bone marrow and peripheral blood contains hematopoietic stem cells and mesenchymal cells able to differentiate into different cell types and that the umbilical cord blood can be a source of stem cells for transplantation. Following this discovery, numerous attempts were made for its potential use in the treatment of hematologic diseases, metabolic diseases as well as regenerative medicine. Umbilical cord blood stem cells exhibit intermediate characteristics between embryonic and adult stem cells. They are distinguished from the latter by telomere length, telomerase activity, and lower risk of accumulation of DNA mutations or chromosomal aberrations. The only transplantation limitation appears to be the amount of cord blood collected, which on average is sufficient for transplantation in a 40-50 kg child. Collection of cord blood is a simple, short-lasting treatment, not causing any danger for a newborn or the mother. Umbilical cord blood is obtained during labor, and then frozen and stored at cord blood banks all over the world. PMID:26206998

  4. 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)

  5. 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. PMID:24273518

  6. Light scattering by aggregated red blood cells.

    PubMed

    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 < or = n < or = 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. PMID:11900021

  7. 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.

  8. Human-induced pluripotent stem cells from blood cells of healthy donors and patients with acquired blood disorders

    PubMed Central

    Ye, Zhaohui; Zhan, Huichun; Mali, Prashant; Dowey, Sarah; Williams, Donna M.; Jang, Yoon-Young; Dang, Chi V.; Spivak, Jerry L.; Moliterno, Alison R.

    2009-01-01

    Human induced pluripotent stem (iPS) cells derived from somatic cells hold promise to develop novel patient-specific cell therapies and research models for inherited and acquired diseases. We and others previously reprogrammed human adherent cells, such as postnatal fibroblasts to iPS cells, which resemble adherent embryonic stem cells. Here we report derivation of iPS cells from postnatal human blood cells and the potential of these pluripotent cells for disease modeling. Multiple human iPS cell lines were generated from previously frozen cord blood or adult CD34+ cells of healthy donors, and could be redirected to hematopoietic differentiation. Multiple iPS cell lines were also generated from peripheral blood CD34+ cells of 2 patients with myeloproliferative disorders (MPDs) who acquired the JAK2-V617F somatic mutation in their blood cells. The MPD-derived iPS cells containing the mutation appeared normal in phenotypes, karyotype, and pluripotency. After directed hematopoietic differentiation, the MPD-iPS cell-derived hematopoietic progenitor (CD34+CD45+) cells showed the increased erythropoiesis and gene expression of specific genes, recapitulating features of the primary CD34+ cells of the corresponding patient from whom the iPS cells were derived. These iPS cells provide a renewable cell source and a prospective hematopoiesis model for investigating MPD pathogenesis. PMID:19797525

  9. The meanings of consent to the donation of cord blood stem cells: perspectives from an interview-based study of a public cord blood bank in England

    PubMed Central

    Busby, Helen

    2010-01-01

    This paper explores the perspectives of women who have agreed that their umbilical cord blood may be collected for a public ‘cord blood bank’, for use in transplant medicine or research. Drawing on interview data from 27 mothers who agreed to the collection and use of their umbilical cord blood, these choices and the informed consent process are explored. It is shown that the needs of sick children requiring transplants are prominent in narrative accounts of cord blood banking, together with high expectations for future applications of stem cells. Given this dynamic, a concern arises that the complex and multiple uses of tissues and related data might be oversimplified in the consent process. In conclusion, the positive finding of a commitment to mutuality in cord blood banking among these women is underlined, and its implications for the wider debate on cord blood banking are discussed. PMID:21666742

  10. Effects of Red Blood Cell Aggregation on the Apparent Viscosity of Blood Flow in Tubes.

    NASA Astrophysics Data System (ADS)

    Hitt, Darren L.; Lowe, Mary L.

    1996-11-01

    In arterioles and venules (20-200μ diameter), the low shear rates enable red blood cells to form aggregate structures of varying sizes and morphology. The size and distribution of the aggregates affect the flow impedance within a microvascular network; this effect may be characterized by an "apparent viscosity". In this study, we measure the apparent viscosity of blood flow in 50μ glass tubes as a function of shear rate and red blood cell volume fraction (hematocrit); for a fixed tube geometry and an imposed flow rate, the viscosity is determined by measuring the pressure drop across the tube. To correlate the apparent viscosity with the size and spatial distribution of the aggregates in the flow, video images of the flow are recorded and analyzed using power spectral techniques. Pig blood and sheep blood are used as the models for aggregating and non-aggregating blood, respectively. Supported by NSF PFF Award CTS-9253633

  11. 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

  12. Effect of Hydroperoxides on Red Blood Cell Membrane Mechanical Properties

    PubMed Central

    Hale, John P.; Winlove, C. Peter; Petrov, Peter G.

    2011-01-01

    We investigate the effect of oxidative stress on red blood cell membrane mechanical properties in vitro using detailed analysis of the membrane thermal fluctuation spectrum. Two different oxidants, the cytosol-soluble hydrogen peroxide and the membrane-soluble cumene hydroperoxide, are used, and their effects on the membrane bending elastic modulus, surface tension, strength of confinement due to the membrane skeleton, and 2D shear elastic modulus are measured. We find that both oxidants alter significantly the membrane elastic properties, but their effects differ qualitatively and quantitatively. While hydrogen peroxide mainly affects the elasticity of the membrane protein skeleton (increasing the membrane shear modulus), cumene hydroperoxide has an impact on both membrane skeleton and lipid bilayer mechanical properties, as can be seen from the increased values of the shear and bending elastic moduli. The biologically important implication of these results is that the effects of oxidative stress on the biophysical properties, and hence the physiological functions, of the cell membrane depend on the nature of the oxidative agent. Thermal fluctuation spectroscopy provides a means of characterizing these different effects, potentially in a clinical milieu. PMID:22004746

  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. Electrochemical Red Blood Cell Counting: One at a Time.

    PubMed

    Sepunaru, Lior; Sokolov, Stanislav V; Holter, Jennifer; Young, Neil P; Compton, Richard G

    2016-08-01

    We demonstrate that the concentration of a red blood cell solution under physiological conditions can be determined by electrochemical voltammetry. The magnitude of the oxygen reduction currents produced at an edge-plane pyrolytic graphite electrode was diagnosed analytically at concentrations suitable for a point-of-care test device. The currents could be further enhanced when the solution of red blood cells was exposed to hydrogen peroxide. We show that the enhanced signal can be used to detect red blood cells at a single entity level. The method presented relies on the catalytic activity of red blood cells towards hydrogen peroxide and on surface-induced haemolysis. Each single cell activity is expressed as current spikes decaying within a few seconds back to the background current. The frequency of such current spikes is proportional to the concentration of cells in solution. PMID:27355839

  15. 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.

  16. 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

  17. A novel hydrophilic polymer-brush pattern for site-specific capture of blood cells from whole blood.

    PubMed

    Hou, Jianwen; Shi, Qiang; Ye, Wei; Fan, Qunfu; Shi, Hengchong; Wong, Shing-Chung; Xu, Xiaodong; Yin, Jinghua

    2015-03-11

    A novel hydrophilic PAMPS-PAAm brush pattern is fabricated to selectively capture blood cells from whole blood. PAMPS brushes provide antifouling surfaces to resist protein and cell adhesion while PAAm brushes effectively entrap targeted proteins for site-specific and cell-type dependent capture of blood cells. PMID:25469596

  18. 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. PMID:27039311

  19. Formation of dimethylthioarsenicals in red blood cells

    SciTech Connect

    Naranmandura, Hua; Suzuki, Kazuo T.

    2008-03-15

    The bladder and skin are the primary targets for arsenic-induced carcinogenicity in mammals. Thioarsenicals dimethylmonothioarsinic (DMMTA{sup V}) and dimethyldithioarsinic (DMDTA{sup V}) acids are common urinary metabolites, the former being much more toxic than non-thiolated dimethylarsinic acid (DMA{sup V}) and comparable to dimethylarsinous acid (DMA{sup III}) in epidermoid cells, suggesting that the metabolic production of thioarsenicals may be a risk factor for the development of cancer in these organs. To reveal their production sites (tissues/body fluids), we examined the uptake and transformation of the four dimethylated arsenicals by incubation with rat and human red blood cells (RBCs). Although DMA{sup V} and DMDTA{sup V} were not taken up by either type of RBCs, DMA{sup III} and DMMTA{sup V} were taken up by both (more efficiently by rat ones), though DMMTA{sup V} was taken up slowly, and then the arsenic transformed into DMDTA{sup V} was excreted from both types of animal RBCs. On the other hand, although DMA{sup III} taken up rapidly by rat RBCs was retained in the RBCs, that taken up by human RBCs was immediately transformed into DMMTA{sup V} and then excreted into the incubation medium without being retained in the RBCs. In a separate experiment, arsenic remaining in primary rat hepatocytes after incubation with 1.5 {mu}M DMA{sup III} was recovered from the incubation medium in the forms of DMA{sup V} and DMMTA{sup V} in the presence of human RBCs, but not in the presence of rat RBCs (in which the arsenic was bound to hemoglobin). Thus, DMMTA{sup V} was detected in the medium only in the presence of human RBCs and increased with incubation time. It was proposed that arsenic is excreted from hepatocytes into the bloodstream in the form of DMA{sup III} and then taken up by RBCs in humans, where it is transformed into DMMTA{sup V} and then excreted again into the bloodstream.

  20. [Cord blood stem cells. Legal basics and problems].

    PubMed

    Dohmen, D

    2004-01-01

    With regard to the great social importance and ethical acceptance of cord blood stem cell research, this article is devoted to basic legal questions concerning the use of umbilical cord blood. The original legal status of the cord blood was analyzed with the result that the cord blood belongs to the child, and thus the child can claim certain personal rights regarding the cord blood. Since the newborn itself is not able to take part in legal transactions, its parents have to ensure that its personal and financial concerns are protected, as they are its legal representatives. The parents can decide together what shall happen to the cord blood because of their parental custody. They have to give their consent to the donation of the cord blood as well as to the collection of personal data of the child. The duty to obtain permission for the production of stem cell preparations derives from the German drug law. Maternity clinics and cord blood banks need this permission and those blood banks that stock up on cord blood stem cell preparations for indefinite recipients have to obtain an additional authorization because these preparations are prefabricated drugs. PMID:15205820

  1. 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

  2. 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.

  3. 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

    2014-01-01

    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

  4. Generation of induced pluripotent stem cells from human blood.

    PubMed

    Loh, Yuin-Han; Agarwal, Suneet; Park, In-Hyun; Urbach, Achia; Huo, Hongguang; Heffner, Garrett C; Kim, Kitai; Miller, Justine D; Ng, Kitwa; Daley, George Q

    2009-05-28

    Human dermal fibroblasts obtained by skin biopsy can be reprogrammed directly to pluripotency by the ectopic expression of defined transcription factors. Here, we describe the derivation of induced pluripotent stem cells from CD34+ mobilized human peripheral blood cells using retroviral transduction of OCT4/SOX2/KLF4/MYC. Blood-derived human induced pluripotent stem cells are indistinguishable from human embryonic stem cells with respect to morphology, expression of surface antigens, and pluripotency-associated transcription factors, DNA methylation status at pluripotent cell-specific genes, and the capacity to differentiate in vitro and in teratomas. The ability to reprogram cells from human blood will allow the generation of patient-specific stem cells for diseases in which the disease-causing somatic mutations are restricted to cells of the hematopoietic lineage. PMID:19299331

  5. Acetylcholinesterase: an enzymatic marker of human red blood cell aging.

    PubMed

    Prall, Y G; Gambhir, K K; Ampy, F R

    1998-01-01

    The purpose of this investigation was to determine whether acetylcholinesterase (AChE) can be used as a marker of cell aging in human red blood cells (RBCs). This study used consented subjects; both males and females in an age range of 21-42 years. The blood samples (8-9 mL) were drawn in tubes containing sodium heparin or EDTA as anticoagulants. To avoid contamination with other cells, (lymphocytes, monocytes and reticulocytes), RBCs were purified (PRBC) by Hypaque-Ficoll gradient technique. The PRBCs were subfractionated into young (y) (1.08-1.09), mid (m) (1.09-1.11) and old (o) (1.11-1.12) percoll density (g/mL) fractions using a discontinuous percoll gradient. The mean +/- 1 SD AChE per gram hemoglobin (U/g Hgb) activities in whole blood (WB) purified human red blood cells (PRBCs), young human red blood cells (y-RBCs), mid age human red blood cells (m-RBCs) and old human red blood cells (o-RBCs) were 27.4 +/- 2.98, 26.0 +/- 2.33, 25.5 +/- 1.64, 20.3 +/- 3.84, 14.6 +/- 3.42 in males and 26.3 +/- 4.44, 24.8 /- 4.83, 26.4 +/- 4.59, 24.0 +/- 5.50 and 12.4 +/- 7.09 in females respectively. Although there was variation in the data, the results indicated that old human red blood cells showed significantly (p<.05) lower AChE activity compared to young human red blood cells of both sexes. These preliminary but novel observations suggest that AChE can be an excellent enzymatic marker for RBC aging in man. PMID:9698047

  6. 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.

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

    PubMed

    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. PMID:23383842

  8. 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

  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. PMID:26608461

  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. [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. PMID:11505724

  12. 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

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

    PubMed Central

    Zeidan, Adel; Yelin, Dvir

    2015-01-01

    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. PMID:26600999

  14. Method for determining properties of red blood cells

    DOEpatents

    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.

  15. The Effect of Shape Memory on Red Blood Cell Motions

    NASA Astrophysics Data System (ADS)

    Niu, Xiting; Shi, Lingling; Pan, Tsorng-Whay; Glowinski, Roland

    2013-11-01

    An elastic spring model is applied to study the effect of the shape memory on the motion of red blood cell in flows. In shear flow, shape memory also plays an important role to obtain all three motions: tumbling, swinging, and tank-treading. In Poiseuille flow, cell has an equilibrium shape as a slipper or parachute depending on capillary number. To ensure the tank-treading motion while in slippery shape, a modified model is proposed by introducing a shape memory coefficient which describes the degree of shape memory in cells. The effect of the coefficient on the cell motion of red blood cell will be presented.

  16. 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

  17. 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.

  18. 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

  19. Muscle metaboreflex and cerebral blood flow regulation in humans: implications for exercise with blood flow restriction.

    PubMed

    Prodel, Eliza; Balanos, George M; Braz, Igor D; Nobrega, Antonio C L; Vianna, Lauro C; Fisher, James P

    2016-05-01

    We investigated the effect of activating metabolically sensitive skeletal muscle afferents (muscle metaboreflex) on cerebral blood flow and the potentially confounding influence of concomitant changes in the partial pressure of arterial carbon dioxide. Eleven healthy males (25 ± 4 yr) performed submaximal leg cycling exercise on a semirecumbent cycle ergometer (heart rate: ∼120 beats/min), and assessments were made of the partial pressure of end-tidal carbon dioxide (PetCO2 ), internal carotid artery blood flow (ICAQ) and conductance (ICACVC), and middle cerebral artery mean blood velocity (MCAvm) and conductance index (MCACVCi).The muscle metaboreflex was activated during cycling with leg blood flow restriction (BFR) or isolated with postexercise ischemia (PEI). In separate trials, PetCO2 was either permitted to fluctuate spontaneously (control trial) or was clamped at 1 mmHg above resting levels (PetCO2 clamp trial). In the control trial, leg cycling with BFR decreased PetCO2 (Δ-4.8 ± 0.9 mmHg vs. leg cycling exercise) secondary to hyperventilation, while ICAQ, ICACVC, and MCAvm were unchanged and MCACVCi decreased. However, in the PetCO2 clamp trial, leg cycling with BFR increased both MCAvm (Δ5.9 ± 1.4 cm/s) and ICAQ (Δ20.0 ± 7.8 ml/min) and attenuated the decrease in MCACVCi, while ICACVC was unchanged. In the control trial, PEI decreased PetCO2 (Δ-7.0 ± 1.3 mmHg vs. rest), MCAvm and MCACVCi, whereas ICAQ and ICACVC were unchanged. In contrast, in the PetCO2 clamp trial both ICAQ (Δ18.5 ± 11.9 ml/min) and MCAvm (Δ8.8 ± 2.0 cm/s) were elevated, while ICACVC and MCACVCi were unchanged. In conclusion, when hyperventilation-related decreases in PetCO2 are prevented the activation of metabolically sensitive skeletal muscle afferent fibers increases cerebral blood flow. PMID:26873971

  20. 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. PMID:26163133

  1. What Is a Blood and Marrow Stem Cell Transplant?

    MedlinePlus

    ... procedure allows the recipient to get new stem cells that work properly. Stem cells are found in bone marrow, ... the body doesn't make enough red blood cells or they don't work properly. Certain immune-deficiency diseases that prevent the ...

  2. 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. PMID:25989392

  3. Who Needs a Blood and Marrow Stem Cell Transplant?

    MedlinePlus

    ... to find out whether you have any medical problems that could cause complications after the transplant. (See "What To Expect Before a Blood and Marrow Stem Cell Transplant" for more information.) Rate This Content: NEXT >> ...

  4. Red blood cell homeostasis: recognition of distinct types of damaged homologous red blood cells by a mouse macrophage cell line.

    PubMed

    Singer, J A; Morrison, M; Walker, W S

    1987-06-01

    The mouse macrophage (M phi) cell line IC-21 preferentially ingests a subpopulation of homologous red blood cells (MRBC) from normal mice. This subpopulation presumably bears the so-called transfusion lesion, a consequence of damage acquired during the drawing and processing of blood. To determine if all damaged MRBC were recognized by a common receptor site on IC-21 M phi, we prepared suspensions of MRBC damaged in vitro by treatment with tannic acid and compared the phagocytic uptake of these cells with those bearing the transfusion lesion. Trypsin treatment of IC-21 M phi rendered them unable to recognize MRBC bearing the transfusion lesion; but it had no effect on the uptake of tannic acid-damaged MRBC, showing that IC-21 M phi have separate recognition sites for these two populations of damaged MRBC. PMID:3474332

  5. Red blood cell and iron metabolism during space flight.

    PubMed

    Smith, Scott M

    2002-10-01

    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. PMID:12361780

  6. 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.

  7. 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. PMID:26867209

  8. 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.

  9. 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

  10. The phenotypic and functional characteristics of umbilical cord blood and peripheral blood natural killer cells.

    PubMed

    Verneris, Michael R; Miller, Jeffrey S

    2009-10-01

    Allogeneic hematopoietic cell transplantation can be curative for patients with high-risk acute leukaemia. Umbilical cord blood (UCB) is an increasingly used source of allogeneic stem cells for patients who are in need of a transplant, but do not have a sibling donor. This review highlights the similarities and differences between the natural killer (NK) cells obtained from adult peripheral blood (PB) and UCB. These two cell sources show similar percentages of NK cells, including the major CD56(dim) and CD56(bright) subpopulations. UCB also contains an additional CD56-CD16+ subset, not typically found in PB. In addition, there are a number of progenitor cell populations in UCB that can give rise to NK cells. Some studies showed that UCB NK cells express a relatively higher percentage of inhibitory receptors (CD94/NKG2A and killer-cell immunoglobulin-like receptors) and less adhesion molecules. Resting UCB NK cells also show significantly less cytotoxicity compared to PB NK cells. However, following cytokine stimulation, the cytotoxicity of UCB NK cells can be rapidly increased to levels that are comparable to PB NK cells. Activation and expansion protocols for UCB NK cells are briefly reviewed. Lastly, we outline the early use of UCB NK cells in clinical trials. PMID:19796267

  11. A Discrete-Element Approach for Blood Cell Adhesion

    NASA Astrophysics Data System (ADS)

    Chesnutt, Jennifer; Marshall, Jeffrey

    2006-11-01

    An efficient computational model for simulation of the individual dynamics of adhering blood cells is discussed. Each cell is represented as a discrete particle so that the model can extend existing discrete-element approaches for dense particulate fluid flows to account for receptor-ligand binding of particles, elliptical particle shape, and deformation of the particles due to shear forces. Capabilities of the method in simulating large numbers of particles are illustrated through simulations of the formation of red blood cell rouleaux in shear flow. The effects of several factors, such as aspect ratio of the elliptical particle, shear rate, strength of the cell adhesion force, and hematocrit are investigated. Comparison of the discrete-element results with results of a level-set approach which computes the entire flow field about a small number of cells is used to develop an improved model of the effect of nearby red blood cells on the cell drag force expression. The method is also being applied to examine the influence of red blood cells on other components of the blood, such as platelet dispersion and activation in high shear regions.

  12. 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. PMID:26415744

  13. 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. PMID:25426572

  14. 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.

  15. Effect of Occupational Exposure on Blood Cell Counts, Electrocardiogram and Blood Pressure in Rice Mill Workers

    PubMed Central

    Aithala, Manjunatha; Das, Kusal Kanti

    2015-01-01

    Introduction Under normal conditions, parasympathetic and sympathetic nervous systems interact to regulate the heart rate of about 70 beats per minute. Activation of sympathetic nervous system by emotional or physical stress increases heart rate and the force of heart beat. There are many factors which alter the heart rate. The chemical and mechanical stimulation of receptors can also cause change in blood pressure through autonomic nervous system. Exposure to dust also causes alteration in blood cell counts. This can be due to allergic reactions and inflammation which in turn evoked by dust entering the lungs. Objectives Aim of the study was to evaluate the effect of occupational exposure on haematological and cardiovascular parameters of rice mill workers by analysing Blood Cell Counts, ECG and Blood Pressure. Materials and Methods This cross-sectional study was carried on 134 rice mill workers and an equal number of age and sex matched healthy individual. The blood cell counts were determined by automated cell counter machine, ECG was recorded by using ECG machine and Blood Pressure was measured by using mercurial sphygmomanometer. Results Neurtrophil, Eosinophil and Lymphocyte count among haematological parameters were significantly increased in exposed individuals. Marked variation was seen in ECG and Blood pressure among cardiovascular parameters of exposed individuals compared with control group. Conclusion The findings of our study clearly indicate that the rice mill workers are under high level of dust exposure which has deleterious effects on their blood and tissues. It is due to high oxidative stress. There are abnormalities seen in cardiovascular system. PMID:26674852

  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

    2015-09-01

    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. PMID:26297409

  17. 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. PMID:25421023

  18. 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

    2016-05-01

    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

  19. Histone modifications: implications in renal cell carcinoma

    PubMed Central

    Ramakrishnan, Swathi; Ellis, Leigh; Pili, Roberto

    2013-01-01

    In 2012, an estimated 64,770 men and women were diagnosed with malignancy of the kidney and renal pelvis, of which 13,570 succumbed to their disease. Common genetic aberrations in renal cell carcinomas (RCCs) include loss of function of the VHL gene in clear-cell RCC, overexpression of the c-MET gene in papillary RCC type I, deficiency in the FH gene in papillary RCC type II and loss of heterozygozity of the BHD gene in chromophobe RCC. Recent studies illustrate epigenetic silencing of VHL, as well as alterations in histone modifications and their governing enzymes. The possibility of reversing these epigenetic marks has resulted in efforts to target these changes by utilizing inhibitors of HDACs, DNA methyltransferases and, recently, histone methyltransferases in preclinical and clinical studies. This article focuses on potential therapeutic interventions, and the implications of histone modifications and related enzyme alterations in RCC. PMID:23895657

  20. Generation of Human Induced Pluripotent Stem Cells from Peripheral Blood Mononuclear Cells Using Sendai Virus.

    PubMed

    Soares, Filipa A C; Pedersen, Roger A; Vallier, Ludovic

    2016-01-01

    This protocol describes the efficient isolation of peripheral blood mononuclear cells from circulating blood via density gradient centrifugation and subsequent generation of integration-free human induced pluripotent stem cells. Peripheral blood mononuclear cells are cultured for 9 days to allow expansion of the erythroblast population. The erythroblasts are then used to derive human induced pluripotent stem cells using Sendai viral vectors, each expressing one of the four reprogramming factors Oct4, Sox2, Klf4, and c-Myc. PMID:25687300

  1. 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.

  2. 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. PMID:23622969

  3. [Introduction and prospect of peripheral blood stem cell transplantation].

    PubMed

    Nakanishi, Y

    1995-12-01

    The number of hematopoietic stem cells circulating in peripheral blood increases remarkably during the recovery of marrow function after myelosuppressive chemotherapy. In peripheral blood stem cell transplantation, these stem cells are collected and cryopreserved, and then used to restore marrow function after myelodisruptive (high-dose) anticancer therapy, Marrow recovery is faster with this procedure than with autologous bone marrow transplantation. Recently, this procedure has been used after high-dose chemotherapy for chemosensitive solid tumors such as breast cancer. We used high-dose chemotherapy with etoposide and carboplatin, followed by peripheral blood stem cell transplantation, to treat 5 patients with intrathoracic malignant tumors, including small cell lung cancer Neutrophils recovered (> 500 microliters) with 9 to 11 days and platelets recovered (> 5,000 microliters) within 8 to 13 days after the transplantation. No other serious complication was seen. Current topics regarding this procedure, problems to be solved, and prospects for further development are discussed. PMID:8752478

  4. Blood-Induced Interference of Glucose Sensor Function in Vitro: Implications for in Vivo Sensor Function

    PubMed Central

    Klueh, Ulrike; Liu, Zenghe; Ouyang, Tianmei; Cho, Brian; Feldman, Ben; Henning, Timothy P.; Kreutzer, Don

    2007-01-01

    Background Although tissue hemorrhages, with resulting blood clots, are associated with glucose sensor implantation, virtually nothing known is about the impact of red blood cells and red blood cell clots on sensor function in vitro or in vivo. In these studies, we tested the hypothesis that blood can directly interfere with glucose sensor function in vitro. Methods To test this hypothesis, heparinized human whole blood (HWB) and nonheparinized human whole blood (WB) were obtained from normal individuals. Aliquots of HWB and WB samples were also fractionated into plasma, serum, and total leukocyte (TL) components. Resulting HWB, WB, and WB components were incubated in vitro with an amperometric glucose sensor for 24 hours at 37°C. During incubation, blood glucose levels were determined periodically using a glucose monitor, and glucose sensor function (GSF) was monitored continuously as nanoampere output. Results Heparinized human whole blood had no significant effect on GSF in vitro, nor did TL, serum, or plasmaderived clots from WB. Sensors incubated with WB displayed a rapid signal loss associated with clot formation at 37°C. The half-life was 0.8 ± 0.2 hours (n = 16) for sensors incubated with WB compared to 3.2 ± 0.5 (n = 12) for sensors incubated with HWB with a blood glucose level of approximately 100 mg/dl. Conclusions These studies demonstrated that human whole blood interfered with GSF in vitro. These studies further demonstrated that this interference was related to blood clot formation, as HWB, serum, plasma-derived clots, or TL did not interfere with GSF in vitro in the same way that WB did. These in vitro studies supported the concept that the formation of blood clots at sites of glucose sensor implantation could have a negative impact on GSF in vivo. PMID:19885155

  5. Plasticity of Blood- and Lymphatic Endothelial Cells and Marker Identification

    PubMed Central

    Keuschnigg, Johannes; Karinen, Sirkku; Auvinen, Kaisa; Irjala, Heikki; Mpindi, John-Patrick; Kallioniemi, Olli; Hautaniemi, Sampsa; Jalkanen, Sirpa; Salmi, Marko

    2013-01-01

    The distinction between lymphatic and blood vessels is biologically fundamental. Here we wanted to rigorously analyze the universal applicability of vascular markers and characteristics of the two widely used vascular model systems human microvascular endothelial cell line-1 (HMEC-1) and telomerase-immortalized microvascular endothelial cell line (TIME). Therefore we studied the protein expression and functional properties of the endothelial cell lines HMEC-1 and TIME by flow cytometry and in vitro flow assays. We then performed microarray analyses of the gene expression in these two cell lines and compared them to primary endothelial cells. Using bioinformatics we then defined 39 new, more universal, endothelial-type specific markers from 47 primary endothelial microarray datasets and validated them using immunohistochemistry with normal and pathological tissues. We surprisingly found that both HMEC-1 and TIME are hybrid blood- and lymphatic cells. In addition, we discovered great discrepancies in the previous identifications of blood- and lymphatic endothelium-specific genes. Hence we identified and validated new, universally applicable vascular markers. Summarizing, the hybrid blood-lymphatic endothelial phenotype of HMEC-1 and TIME is indicative of plasticity in the gene expression of immortalized endothelial cell lines. Moreover, we identified new, stable, vessel-type specific markers for blood- and lymphatic endothelium, useful for basic research and clinical diagnostics. PMID:24058540

  6. Mutation assays involving blood cells that metabolize toxic substances

    SciTech Connect

    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.

  7. 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.

  8. Adoptive Immunotherapy using Regulatory T cells and Virus-specific T cells Derived from Cord Blood

    PubMed Central

    Hanley, Patrick J.; Bollard, Catherine M.; Brunstein, Claudio G

    2014-01-01

    Cord blood transplantation, an alternative to traditional stem cell transplants (bone marrow or peripheral blood stem cell transplantation), is an attractive option for patients lacking suitable stem cell transplant donors. Cord blood units have also proven to be a valuable donor source for the development of cellular therapeutics. Virus-specific T cells and regulatory T cells are two cord blood derived products that have shown promise in early phase clinical trials to prevent and/or treat viral infections and graft-versus-host disease (GvHD), respectively. Here we describe how current strategies utilizing cord blood-derived regulatory T cells and virus-specific T cells have been developed to improve outcomes for cord blood transplant recipients. PMID:25632003

  9. Rheology of blood cells as soft tissues.

    PubMed

    Skalak, R; Chien, S

    1982-01-01

    Erythrocytes are unusual in that the cell membrane plays a large and direct role in observed rheological properties. The cell membrane is not a three dimensional material or tissue in the usual sense but being only two molecules thick. It behaves like a liquid sheet of constant thickness and surface area with some elastic properties due in part to protein networks of spectrin and actin on the interior face of the cell membrane. Packed red cells form a viscoelastic fluid which can be sheared, but exhibits a considerable elastic response. The elastic component decreases as the hematocrit is reduced, but is present at all hematocrits. Leukocytes also exhibit viscoelasticity but the properties are primarily dependent on the cell cytoplasm. The cell membrane plays a role only when it is stretched taut. The normal white cell properties have been explored over a wide range of osmolarities, becoming much less viscous and less elastic as the fluid content of the cell increases. White cells also may show spontaneous deformation during which the rheological properties become much stiffer than in the normal passive state. PMID:7104483

  10. 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

  11. 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

  12. 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

  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. Cell trapping in a blood capillary phantom using laser tweezers

    NASA Astrophysics Data System (ADS)

    Klykov, Sergei S.; Fedosov, Ivan V.; Tuchin, Valery V.

    2015-03-01

    As a phantom of native blood capillary the plastic capillary tube and as a model of red blood cells the yeast cells are considered. Plastic capillary has circular a cross-section with diameter ranging between 20 and 40 μ. For velocity estimation of polystyrene beads which had a role of tracers in water the particle image velocimetry method is realized using NI Labview Vision standard functions of image processing. It is shown that in spite of the presence of uncompensated spherical aberration emerging from refraction incident beam in curved plastic capillary walls yeast cells can be confined in stable 3D trap.

  15. 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.

  16. 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. PMID:26819256

  17. 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

  18. 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.

  19. 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.

  20. 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

  1. 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.

  2. Blood flow structure related to red cell flow: determinant of blood fluidity in narrow microvessels.

    PubMed

    McHedlishvili, G; Maeda, N

    2001-02-01

    The review article deals with phenomena of the blood flow structure (structuring) in narrow microvessels-capillaries and the adjacent arterioles and venules. It is particularly focused on the flow behavior of red blood cells (RBCs), namely, on their specific arrangements of mutual interaction while forming definite patterns of self-organized microvascular flow. The principal features of the blood flow structure in microvessels, including capillaries, include axial RBC flow and parietal plasma layer, velocity profile in larger microvessels, plug (or bolus) flow in narrow capillaries, and deformation and specific behavior of the RBCs in the flow. The actual blood flow structuring in microvessels seems to be a most significant factor in the development of pathological conditions, including arterial hypertension, brain and cardiac infarctions, inflammation, and many others. The blood flow structuring might become a basic concept in determining the blood rheological properties and disorders in the narrow microvessels. No solid theoretical (biorheological) basis of the blood flow structuring in microvessel has been found, but in the future it might become a foundation for a better understanding of the mechanisms of these properties under normal and pathological conditions in the narrowest microvessels 5 to 25 microm large. It is also a topic for further biorheological research directed to find the background of actual physiopathological phenomena in the microcirculation. PMID:11281993

  3. 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

  4. 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. PMID:26671221

  5. 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. PMID:16798803

  6. Blood Thixotropy in Patients with Sickle Cell Anaemia: Role of Haematocrit and Red Blood Cell Rheological Properties

    PubMed Central

    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. PMID:25502228

  7. 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

    2016-02-01

    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. PMID:26855752

  8. 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.

  9. B cells and platelets harbor prion infectivity in the blood of deer infected with chronic wasting disease.

    PubMed

    Mathiason, Candace K; Hayes-Klug, Jeanette; Hays, Sheila A; Powers, Jenny; Osborn, David A; Dahmes, Sallie J; Miller, Karl V; Warren, Robert J; Mason, Gary L; Telling, Glenn C; Young, Alan J; Hoover, Edward A

    2010-05-01

    Substantial evidence for prion transmission via blood transfusion exists for many transmissible spongiform encephalopathy (TSE) diseases. Determining which cell phenotype(s) is responsible for trafficking infectivity has important implications for our understanding of the dissemination of prions, as well as their detection and elimination from blood products. We used bioassay studies of native white-tailed deer and transgenic cervidized mice to determine (i) if chronic wasting disease (CWD) blood infectivity is associated with the cellular versus the cell-free/plasma fraction of blood and (ii) in particular if B-cell (MAb 2-104(+)), platelet (CD41/61(+)), or CD14(+) monocyte blood cell phenotypes harbor infectious prions. All four deer transfused with the blood mononuclear cell fraction from CWD(+) donor deer became PrP(CWD) positive by 19 months postinoculation, whereas none of the four deer inoculated with cell-free plasma from the same source developed prion infection. All four of the deer injected with B cells and three of four deer receiving platelets from CWD(+) donor deer became PrP(CWD) positive in as little as 6 months postinoculation, whereas none of the four deer receiving blood CD14(+) monocytes developed evidence of CWD infection (immunohistochemistry and Western blot analysis) after 19 months of observation. Results of the Tg(CerPrP) mouse bioassays mirrored those of the native cervid host. These results indicate that CWD blood infectivity is cell associated and suggest a significant role for B cells and platelets in trafficking CWD infectivity in vivo and support earlier tissue-based studies associating putative follicular B cells with PrP(CWD). Localization of CWD infectivity with leukocyte subpopulations may aid in enhancing the sensitivity of blood-based diagnostic assays for CWD and other TSEs. PMID:20219916

  10. Blood Disorders

    MedlinePlus

    ... and protein. Over half of your blood is plasma. The solid part of your blood contains red blood cells, white blood cells and platelets. Blood disorders affect one or more parts of the blood and prevent ...

  11. 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. PMID:26701327

  12. Non-Hematopoietic Stem Cells in Umbilical Cord Blood

    PubMed Central

    Matsumoto, Taro; Mugishima, Hideo

    2009-01-01

    Allogeneic umbilical cord blood (UCB) transplantation has been used to treat a variety of malignant and non-malignant diseases. Recent studies show convincing evidence that UCB contains not only hematopoietic progenitors, but also several types of stem and progenitor cells providing a high proliferative capacity and a variety of differentiation potentials. UCB-derived cells offer multiple advantages over adult stem cells from other sources like bone marrow (BM), because UCB can be collected without painful procedure, easily available in virtually unlimited supply, and has not been exposed to immunologic challenge. In addition, cord blood transplantation is now an established field with great potential and no serious ethical issue by establishment of public UCB banks throughout the world. Therefore UCB-derived non-hematopoietic stem cells may provide an attractive cell source for tissue repair and regeneration. It is generally accepted that UCB contains endothelial progenitor cells (EPC), mesenchymal stromal cells (MSC), unrestricted somatic stem cells (USSC), very small embryonic-like stem cells (VSEL), multilineage progenitor cells (MLPC), and neuronal progenitor cells. This review focuses on biological properties of these non-hematopoietic stem/progenitor cells derived from human UCB and their potential use in cell based therapies. PMID:24855525

  13. Generation of iPS Cells from Human Peripheral Blood Mononuclear Cells Using Episomal Vectors.

    PubMed

    Su, Ruijun Jeanna; Neises, Amanda; Zhang, Xiao-Bing

    2016-01-01

    Peripheral blood is the easy-to-access, minimally invasive, and the most abundant cell source to use for cell reprogramming. The episomal vector is among the best approaches for generating integration-free induced pluripotent stem (iPS) cells due to its simplicity and affordability. Here we describe the detailed protocol for the efficient generation of integration-free iPS cells from peripheral blood mononuclear cells. With this optimized protocol, one can readily generate hundreds of iPS cell colonies from 1 ml of peripheral blood. PMID:25403468

  14. 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.

  15. [Endothelial cells in the blood in psoriasis].

    PubMed

    Sochorova, R; Sinka, L; Svecova, D; Benova, B; Rybarova, L

    2000-01-01

    The authors have examined the changes in the amount of endothelial cells in vascular bed in psoriatic patients, since one of the basic signs of pathogenesis of psoriasis is represented by angiogenesis. The authors have used the method of quantitative evaluation of endothelaemia. PMID:11187061

  16. Mast cell mediators in the blood of patients with asthma.

    PubMed

    Wasserman, S I

    1985-01-01

    Mast cell activation occurs in allergic asthma and may play a role in a variety of nonallergic asthmatic states. The defined mast cell constituent histamine has been identified in blood of antigen-sensitive challenged asthma patients, while other mediators, whose cell of origin is not fully defined, accompany this amine in blood (Table 1). Due to technical difficulty in accurate assessment, the rapid metabolism of various constituents, and the need for biologic rather than chemical assay of some mediators, it is not yet possible to assess blood constituents for the unequivocal attribution of asthma to activation of a particular cell type. Likewise, the usefulness of blood studies in the prediction of the course of asthma or as serial measurements to define the severity of asthma remains limited. However, it is only with analysis of the appropriate biologic fluids, blood and/or bronchoalveolar lavage materials, that it will be possible to define which potential mediators are, in fact, present and active in asthma. Until such analysis is completed, it is not possible to assign a function in this disease to the numerous potent inflammatory mediators known to be active in in vitro or in vivo models of asthma. PMID:3880526

  17. 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). PMID:27282583

  18. 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.

  19. 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

  20. 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.

  1. Dual network model for red blood cell membranes

    NASA Astrophysics Data System (ADS)

    Boal, David H.; Seifert, Udo; Zilker, Andreas

    1992-12-01

    A two-component network is studied by Monte Carlo simulation to model the lipid/spectrin membrane of red blood cells. The model predicts that the shear modulus decreases rapidly with the maximum length of the model spectrin and should be in the 10-7 J/m2 range for human red blood cells. A simplified model for the isolated spectrin network shows a negative Lamé coefficient λ. Transverse fluctuations of the dual membrane are found to be fluidlike over the range of wavelengths investigated.

  2. 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.

  3. 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.

  4. 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

  5. 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.

  6. 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

    2016-01-01

    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. PMID:27050968

  7. 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

    2016-05-01

    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. PMID:26916508

  8. Related Hematopoietic Stem Cell Transplantation (HSCT) for Genetic Diseases of Blood Cells

    ClinicalTrials.gov

    2016-05-11

    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

  9. Membranotropic photobiomodulation on red blood cell deformability

    NASA Astrophysics Data System (ADS)

    Luo, Gang-Yue; Zhao, Yan-Ping; Liu, Timon C.; Liu, Song-Hao

    2007-05-01

    To assess modulation of laser on erythrocyte permeability and deformability via cell morphology changes, healthy human echinocytes with shrinking size and high plasmic viscosity due to cellular dehydration were treated with 1 mW, 2 mW, 3 mW, and 5 mW laser power exposure respectively. Image analyzing system on single intact erythrocyte was applied for measuring comprehensive cell morphological parameters (surface area, external membrane perimeter, circle index and elongation index) that were determined by the modulation of erythrocyte water permeability and deformability to detect relationship between erythrocyte water permeability alteration and deformability. Our preliminary experiment showed that exposure under light dose of 5 mW for 5 min could induce more active erythrocyte swelling and deformation. water channel aquaporin-1(AQP-1) was inhibited by the incubation of HgCl II in the presence and absence of 5 mW laser irradiation. The result suggested that osmotic water permeability is a primary factor in the procedure of erythrocyte deformability. In addition, no modulation of laser(5mW) on erythrocyte deformability had been found when the echinocytes were cultured with GDP-β-S (G protein inhibitor).

  10. 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

  11. Cord Blood as a Source of Natural Killer Cells.

    PubMed

    Mehta, Rohtesh S; Shpall, Elizabeth J; Rezvani, Katayoun

    2015-01-01

    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

  12. Mononuclear cells from a rare blood donor, after freezing under good manufacturing practice conditions, generate red blood cells that recapitulate the rare blood phenotype

    PubMed Central

    Masiello, Francesca; Tirelli, Valentina; Sanchez, Massimo; van den Akker, Emile; Girelli, Gabriella; Marconi, Maurizio; Villa, Maria Antonietta; Rebulla, Paolo; Hashmi, Gazala; Whitsett, Carolyn; Migliaccio, Anna Rita

    2013-01-01

    Background Cultured red blood cells (cRBCs) from cord blood (CB) have been proposed as transfusion products. Whether buffy-coats discarded from blood donations (AB) may be used to generate cRBCs for transfusion has not been investigated. Study Design and Methods Erythroid progenitor cell content and numbers and blood group antigen profiles of erythroblasts (ERYs) and cRBCs generated in Human Erythroid Massive Amplification (HEMA) culture by CB (n=7) and AB (n=33, three females, three males, one AB with rare blood antigens cryopreserved using CB protocols) were compared. Results Variability was observed both in progenitor cell content (2-fold) and number of ERYs generated (1-log) by CB and AB in HEMA. The average progenitor cell contents of the subset of AB and CB analyzed were similar. AB generated numbers of ERYs 3-times lower (p<0.01) than CB in HEMA containing fetal bovine serum but similar to CB in HEMA containing human proteins. Female AB contained 2-times less (p<0.05) erythroid progenitor cells but generated numbers of ERYs similar to those generated by male AB. Cryopreserved AB with a rare blood group phenotype and shipped to another laboratory generated great numbers of ERYs, 90% of which matured into cRBCs. Blood group antigen expression was consistent with the donor genotype for ERYs generated both by CB and AB but concordant with that of native RBCs only for cells derived from AB. Conclusion Buffy-coats from regular donors, including a donor with rare phenotypes stored under conditions established for CB, are not inferior to CB for the generation of cRBCs. PMID:24004289

  13. Daily variation in radiosensitivity of circulating blood cells and bone marrow cell density in mice

    SciTech Connect

    Tabatabai, R.N.

    1984-01-01

    Mice on a 12/12 light/dark cycle were bled during a twenty-four hour period each week for eight weeks to establish daily values of circulating blood cells. No significant daily variation was found in total red blood cells, hematocrit, or percentage of reticulocytes. A significant (P < 0.001) daily variation was found in total white blood cells, with the minimum occurring at 8 PM and the maximum occurring during the daylight hours from 8 a.m. to 2 p.m. Mice were then exposed to 0 R, 20 R, 50 R, or 100 R of x-radiation to determine what dose significantly reduces the total white cell count in circulating blood. It was found that 100 R significantly (P < .05) reduces the total white cell count over a four week period post-exposure. To determine if circulating blood cells and bone marrow cells show a diurnal radiosensitivity, mice were exposed to 100 R or 200 R of x-radiation at noon or midnight. Hematocrits, reticulocyte and white blood cell counts, daily white blood cell rhythm, and bone marrow cell density indicate that these mice were more radiosensitive at night.

  14. Aggregation of red blood cells: From rouleaux to clot formation

    NASA Astrophysics Data System (ADS)

    Wagner, Christian; Steffen, Patrick; Svetina, Saša

    2013-06-01

    Red blood cells are known to form aggregates in the form of rouleaux. This aggregation process is believed to be reversible, but there is still no full understanding on the adhesion mechanism. There are at least two competing models, based either on bridging or on depletion. We review recent experimental results on the single cell level and theoretical analyses of the depletion model and of the influence of the cell shape on the adhesion strength. Another important aggregation mechanism is caused by activation of platelets. This leads to clot formation which is life-saving in the case of wound healing, but also a major cause of death in the case of a thrombus induced stroke. We review historical and recent results on the participation of red blood cells in clot formation.

  15. Cord Blood Cells for Developmental Toxicology and Environmental Health

    PubMed Central

    Il’yasova, Dora; Kloc, Noreen; Kinev, Alexander

    2015-01-01

    The Tox21 program initiated a shift in toxicology toward in vitro testing with a focus on the biological mechanisms responsible for toxicological response. We discuss the applications of these initiatives to developmental toxicology. Specifically, we briefly review current approaches that are widely used in developmental toxicology to demonstrate the gap in relevance to human populations. An important aspect of human relevance is the wide variability of cellular responses to toxicants. We discuss how this gap can be addressed by using cells isolated from umbilical cord blood, an entirely non-invasive source of fetal/newborn cells. Extension of toxicological testing to collections of human fetal/newborn cells would be useful for better understanding the effect of toxicants on fetal development in human populations. By presenting this perspective, we aim to initiate a discussion about the use of cord blood donor-specific cells to capture the variability of cellular toxicological responses during this vulnerable stage of human development. PMID:26697419

  16. Concise review: programming human pluripotent stem cells into blood.

    PubMed

    Easterbrook, Jennifer; Fidanza, Antonella; Forrester, Lesley M

    2016-06-01

    Blood disorders are treated with cell therapies including haematopoietic stem cell (HSC) transplantation as well as platelet and red blood cell transfusions. However the source of cells is entirely dependent on donors, procedures are susceptible to transfusion-transmitted infections and serious complications can arise in recipients due to immunological incompatibility. These problems could be alleviated if it was possible to produce haematopoietic cells in vitro from an autologous and renewable cell source. The production of haematopoietic cells in the laboratory from human induced pluripotent stem cells (iPSCs) may provide a route to realize this goal but it has proven challenging to generate long-term reconstituting HSCs. To date, the optimization of differentiation protocols has mostly relied on the manipulation of extrinsic signals to mimic the in vivo environment. We review studies that have taken an alternative approach to modulate intrinsic signals by enforced expression of transcription factors. Single and combinations of multiple transcription factors have been used in a variety of contexts to enhance the production of haematopoietic cells from human pluripotent stem cells. This programming approach, together with the recent advances in the production and use of synthetic transcription factors, holds great promise for the production of fully functional HSCs in the future. PMID:26996518

  17. Isolation of equine peripheral blood mononuclear cells using Percoll.

    PubMed

    May, S A; Hooke, R E; Lees, P

    1991-01-01

    The concentration of Percoll required for isolating equine peripheral blood mononuclear cells has been reinvestigated. A poor cell yield was obtained at the 60 per cent concentration already reported. It is recommended that workers specifically interested in high yields of mononuclear cells, for investigation of lymphocyte and monocyte functions, use a concentration of 65 per cent Percoll. However, workers wishing to isolate pure populations of equine neutrophils might consider a concentration of 70 per cent in the upper layer of Percoll used to retain the mononuclear cells. PMID:1646471

  18. Red Blood Cell Spectrin Skeleton in the Spotlight.

    PubMed

    Braun-Breton, Catherine; Abkarian, Manouk

    2016-02-01

    Das et al. recently reported a role for the major merozoite surface protein MSP1 in malarial parasite egress from the red blood cell (RBC). On the basis of these new data and physical considerations, we propose an updated model for the main steps of this essential process for parasite proliferation. PMID:26652974

  19. Dynamic deformability of sickle red blood cells in microphysiological flow

    PubMed Central

    Alapan, Y.; Matsuyama, Y.; Little, J. A.; Gurkan, U. A.

    2016-01-01

    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. PMID:27437432

  20. Estimating the size of blood cells by staring into space

    NASA Astrophysics Data System (ADS)

    Keeports, David

    1998-01-01

    An order-of-magnitude estimate of the size of red blood cells is obtained by locating a distant object whose height in the visual field matches that of an eye floater and then calculating the retinal image height of that object.

  1. On the birefringence of healthy and malaria-infected red blood cells

    NASA Astrophysics Data System (ADS)

    Dharmadhikari, Aditya K.; Basu, Himanish; Dharmadhikari, Jayashree A.; Sharma, Shobhona; Mathur, Deepak

    2013-12-01

    The birefringence of a red blood cell (RBC) is quantitatively monitored as it becomes infected by a malarial parasite. Large changes occur in the cell's refractive index at different stages of malarial infection. The observed rotation of an optically trapped, malaria-infected RBC is not a simple function of shape distortion: the malarial parasite is found to itself exercise a profound influence on the rotational dynamics by inducing stage-specific birefringence. Our measurements shed new light on the competition between shape- and form-birefringence in RBCs. We demonstrate the possibility of using birefringence to establish very early stages of infected parasites and of assessing various factors that contribute to birefringence in normal and infected cells. Our results have implications for the development and use of noninvasive techniques of quantifying changes in cell properties induced by malaria disease pathology.

  2. Viscoelastic properties of whole blood. Influence of fast sedimenting red blood cell aggregates.

    PubMed

    Schneditz, D; Rainer, F; Kenner, T

    1987-01-01

    Red blood cell (RBC) aggregation is known to be of deciding influence on erythrocyte sedimentation-rate (ESR) and on whole blood viscoelastic properties. The rheological behaviour of blood collected from a control-group with normal ESR is compared to the viscoelastic behaviour of blood collected from two groups with high to very high ESR, whose individuals are suffering from chronical polyarthritis and Morbus Bechterew, respectively. The rheological properties are evaluated by means of an oscillating-flow capillary-rheometer where the viscous (eta') and elastic (eta") component of the complex viscosity (eta) is measured at a constant frequency of 2 Hz. Correcting for the varying hematocrit of the different blood samples according to an exponential equation, the viscoelastic data are found to be elevated in the groups with high ESR. For the viscous properties this is only due to the increase of the plasma viscosity. A correction for the plasma viscosity, however, shows that the viscous properties at low shear- rates (2s-1) are significantly reduced, whereas elastic properties in a range of medium shear-rates (10s-1 to 50s-1) are significantly increased (P less than 0.001, t-test of Student). This result is discussed to be due to the high packing density of the RBC in fast sedimenting aggregates. High packing density reduces the effective volume of the RBC but increases the stiffness of the aggregates. PMID:3651579

  3. Chemical Basis for Qualitative and Quantitative Differences Between ABO Blood Groups and Subgroups: Implications for Organ Transplantation.

    PubMed

    Jeyakanthan, M; Tao, K; Zou, L; Meloncelli, P J; Lowary, T L; Suzuki, K; Boland, D; Larsen, I; Burch, M; Shaw, N; Beddows, K; Addonizio, L; Zuckerman, W; Afzali, B; Kim, D H; Mengel, M; Shapiro, A M J; West, L J

    2015-10-01

    Blood group ABH(O) carbohydrate antigens are carried by precursor structures denoted type I-IV chains, creating unique antigen epitopes that may differ in expression between circulating erythrocytes and vascular endothelial cells. Characterization of such differences is invaluable in many clinical settings including transplantation. Monoclonal antibodies were generated and epitope specificities were characterized against chemically synthesized type I-IV ABH and related glycans. Antigen expression was detected on endomyocardial biopsies (n = 50) and spleen (n = 11) by immunohistochemical staining and on erythrocytes by flow cytometry. On vascular endothelial cells of heart and spleen, only type II-based ABH antigens were expressed; type III/IV structures were not detected. Type II-based ABH were expressed on erythrocytes of all blood groups. Group A1 and A2 erythrocytes additionally expressed type III/IV precursors, whereas group B and O erythrocytes did not. Intensity of A/B antigen expression differed among group A1 , A2 , A1 B, A2 B and B erythrocytes. On group A2 erythrocytes, type III H structures were largely un-glycosylated with the terminal "A" sugar α-GalNAc. Together, these studies define qualitative and quantitative differences in ABH antigen expression between erythrocytes and vascular tissues. These expression profiles have important implications that must be considered in clinical settings of ABO-incompatible transplantation when interpreting anti-ABO antibodies measured by hemagglutination assays with reagent erythrocytes. PMID:26014598

  4. The white blood cell scan in orthopedics

    SciTech Connect

    Propst-Proctor, S.L.; Dillingham, M.F.; McDougall, I.R.; Goodwin, D.

    1982-08-01

    A new nuclear scanning technique was found more specific for bone, joint, and soft tissue infections than any previously described scanning technique. The leukocyte scan, whereby a patient's own cells are labeled with a radioactive tagging agent (/sup 111/In oxine), can distinguish an active infectious process from other pain-inducing conditions. Ninety-seven /sup 111/In labeled autologous leukocyte scans were performed in 88 patients. The findings in 17 of 40 patients scanned for possible acute osteomyelitis, six of nine for suspected septic arthritis, and six for possible soft tissue infections, were positive. Subsequent clinical courses verified the infectious nature of these processes in all patients. Patients who had chronic osteomyelitis (14), bony metastases (four patients), heterotopic ossification (three), and degenerative arthritis (two) demonstrated negative findings. Of the seven patients scanned for acute long-bone fractures, one demonstrated positive findings. Nine scans demonstrated positive findings without determined causes. The leukocyte scan is a useful addition to the diagnostic tools of the orthopedic surgeon.

  5. New ceramics-related industry implicated in elevated blood lead levels in children

    SciTech Connect

    Kaye, W.E.; Novotny, T.E.; Tucker, M.

    1987-05-01

    Elevated lead levels have been implicated as a cause of a variety of health problems in children. Blood lead, erythrocyte protoporphyrin, and hemoglobin levels were measured for family members of workers exposed to lead borosilicate dust in a capacitor and resistor plant in Colorado. Previous studies in other lead-related industries have shown an increased risk of lead poisoning among workers' children through exposure to dust brought home on work clothes. Eighty-nine family members of 41 exposed workers were tested along with 62 family members of 30 unexposed comparison households. The mean blood lead level in the family members of exposed workers was significantly elevated compared with that of the unexposed group (10.2 vs. 6.2 micrograms/dl, p = .0001).

  6. Human blood cells at microgravity: the NASA Initial Blood Storage Experiment.

    PubMed

    Surgenor, D M; Kevy, S V; Chao, F C; Lionetti, F J; Kenney, D M; Jacobson, M S; Kim, B; Ausprunk, D H; Szymanski, I O; Button, L N

    1990-09-01

    The Initial Blood Storage Experiment (IBSE) probed the behavior of human red cells, white cells, and platelets during exposure to microgravity for 6 days and 2 hours on a National Aeronautics and Space Administration (NASA) shuttle mission, named STS 61-C, which was launched on January 12, 1986. IBSE involved carefully controlled comparisons between two identical sets of blood cells, one exposed to microgravity and the other held on the ground. Specially designed and fabricated, electrically powered environmental chambers provided appropriate environmental temperatures and air flow to support cell metabolism throughout the experiment. To circumvent the need for constant agitation of platelets during storage, a new thin-layer compression method for platelet preservation was developed. Blood cell samples were allocated to the two arms of the experiment, microgravity and earth gravity, by blind assignment. Moreover, to ensure unbiased assessment of the experiment's findings, postexperiment samples for measurement were identified by code. To optimize the chances of detecting possible gravitational effects, a wide array of measurements of cellular function, morphology, metabolism, and immunology were made. Analysis of variance was used in analyzing the data. The most striking finding was that platelets displayed markedly superior structural and functional integrity at microgravity. Granulocytes held on the ground were preserved slightly better than those that orbited in the shuttle, whereas red cells displayed few effects that were attributable to the gravitational variable. Polyvinylchloride-di-(2-ethylhexyl)phthalate (PVC-DEHP) was the plastic of choice for storage of red cells, while PVC-trioctyltrimellitate (TOTM) was superior to PVC-DEHP and polyolefin (PO) for platelets. PMID:2402774

  7. Population Pharmacokinetics of Azithromycin in Whole Blood, Peripheral Blood Mononuclear Cells, and Polymorphonuclear Cells in Healthy Adults

    PubMed Central

    Sampson, M R; Dumitrescu, T P; Brouwer, K L R; Schmith, V D

    2014-01-01

    Azithromycin's extensive distribution to proinflammatory cells, including peripheral blood mononuclear cells (PBMCs) and polymorphonuclear cells (PMNs), may be important to its antimicrobial and anti-inflammatory properties. The need to simultaneously predict azithromycin concentrations in whole blood (“blood”), PBMCs, and PMNs motivated this investigation. A single-dose study in 20 healthy adults was conducted, and nonlinear mixed effects modeling was used to simultaneously describe azithromycin concentrations in blood, PBMCs, and PMNs (simultaneous PK model). Data were well described by a four-compartment mamillary model. Apparent central clearance and volume of distribution estimates were 67.3 l/hour and 336 l (interindividual variability of 114 and 122%, respectively). Bootstrapping and visual predictive checks showed adequate model performance. Azithromycin concentrations in blood, PBMCs, and PMNs from external studies of healthy adults and cystic fibrosis patients were within the 5th and 95th percentiles of model simulations. This novel empirical model can be used to predict azithromycin concentrations in blood, PBMCs, and PMNs with different dosing regimens. PMID:24599342

  8. Filterability of blood cells: methods and clinical applications.

    PubMed

    Nash, G B

    1990-01-01

    It could be claimed that expansion in clinical aspects of haemorheology has largely been fueled by the development of a simple test of blood flow properties, i.e., analysis of filterability. With time, the level of sophistication in equipment, theory and sample preparation has increased. Theories for the development of flow in the filter have been described and these enable cellular parameters, such as transit times, to be calculated from experimental data. These theories can be quite general, and applied to filtration of red or white cells. Ideally, experimental design requires an understanding of cell behaviour at the filter and of the effects of factors such as the sample concentration and volume, and the presence of different types of cells or subpopulations. Otherwise, results are susceptible to misinterpretation, particularly if impurities or mixed populations of cells are present. It is thus very important to know accurately the constituents of the test suspension. In clinical applications the trend has been to move away from whole blood filtration, toward use of relatively pure suspension of separated red cells and white cells. In the area of red cell filtration this has led to reappraisal of some previously reported abnormalities. The relatively new study of white cell filtration should benefit from previous experience, but there is the added problem of the reactivity of the cells under test, and their mixed nature. In any case, critical evaluation of the meaning and clinical relevance of results is necessary. PMID:2093395

  9. The involvement of cation leaks in the storage lesion of red blood cells

    PubMed Central

    Flatt, Joanna F.; Bawazir, Waleed M.; Bruce, Lesley J.

    2014-01-01

    Stored blood components are a critical life-saving tool provided to patients by health services worldwide. Red cells may be stored for up to 42 days, allowing for efficient blood bank inventory management, but with prolonged storage comes an unwanted side-effect known as the “storage lesion”, which has been implicated in poorer patient outcomes. This lesion is comprised of a number of processes that are inter-dependent. Metabolic changes include a reduction in glycolysis and ATP production after the first week of storage. This leads to an accumulation of lactate and drop in pH. Longer term damage may be done by the consequent reduction in anti-oxidant enzymes, which contributes to protein and lipid oxidation via reactive oxygen species. The oxidative damage to the cytoskeleton and membrane is involved in increased vesiculation and loss of cation gradients across the membrane. The irreversible damage caused by extensive membrane loss via vesiculation alongside dehydration is likely to result in immediate splenic sequestration of these dense, spherocytic cells. Although often overlooked in the literature, the loss of the cation gradient in stored cells will be considered in more depth in this review as well as the possible effects it may have on other elements of the storage lesion. It has now become clear that blood donors can exhibit quite large variations in the properties of their red cells, including microvesicle production and the rate of cation leak. The implications for the quality of stored red cells from such donors is discussed. PMID:24987374

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

    NASA Astrophysics Data System (ADS)

    Ciasca, G.; Papi, M.; di Claudio, S.; Chiarpotto, M.; Palmieri, V.; Maulucci, G.; Nocca, G.; Rossi, C.; de Spirito, M.

    2015-10-01

    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.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

  11. The Wall-stress Footprint of Blood Cells Flowing in Microvessels

    PubMed Central

    Freund, Jonathan B.; Vermot, Julien

    2014-01-01

    It is well known that mechanotransduction of hemodynamic forces mediates cellular processes, particularly those that lead to vascular development and maintenance. Both the strength and space-time character of these forces have been shown to affect remodeling and morphogenesis. However, the role of blood cells in the process remains unclear. We investigate the possibility that in the smallest vessels blood’s cellular character of itself will lead to forces fundamentally different than the time-averaged forces usually considered, with fluctuations that may significantly exceed their mean values. This is quantitated through the use of a detailed simulation model of microvessel flow in two principal configurations: a diameter D=6.5μm tube—a model for small capillaries through which red blood cells flow in single-file—and a D=12μm tube—a model for a nascent vein or artery through which the cells flow in a confined yet chaotic fashion. Results in both cases show strong sensitivity to the mean flow speed U. Peak stresses exceed their means by greater than a factor of 10 when U/D≲10 s−1, which corresponds to the inverse relaxation time of a healthy red blood cell. This effect is more significant for smaller D cases. At faster flow rates, including those more commonly observed under normal, nominally static physiological conditions, the peak fluctuations are more comparable with the mean shear stress. Implications for mechanotransduction of hemodynamic forces are discussed. PMID:24507616

  12. Reduced blood BDCA-2+ (lymphoid) and CD11c+ (myeloid) dendritic cells in systemic lupus erythematosus

    PubMed Central

    Migita, K; Miyashita, T; Maeda, Y; Kimura, H; Nakamura, M; Yatsuhashi, H; Ishibashi, H; Eguchi, K

    2005-01-01

    Type 1 IFN is thought to be implicated in the autoimmune process of SLE. Plasmacytoid dendric cells (DC), which are natural IFN-α producing cells, play a pivotal epipathogenic role in SLE. The present study was undertaken to investigate the phenotypic characteristics of peripheral blood DC in SLE patients in comparison with those of healthy controls. Samples from 20 SLE patients and 18 healthy controls were studied. Three-colour flow cytometry was performed to identify myeloid DC, as CD11c+ lineage marker−, and HLA-DR+ cells and plasmacytoid DC, as BDCA-2+ linage marker−, and HLA-DR+ cells. We used the whole blood ‘lyse/no-wash’ procedure, which allows precise counting of peripheral blood DC. BDCA-2+ plasmacytoid DC and CD11c+ myeloid DC were reduced in SLE patients compared with controls. Similarly, BDCA-3+ DC were reduced in SLE patients. These results indicated that SLE patients had a reduced number of both BDCA-2+ plasmacytoid DC and CD11c+ myeloid DC. These alternations of the DC subset may drive the autoimmune response in SLE. PMID:16178860

  13. A Systems-Level Interrogation Identifies Regulators of Drosophila Blood Cell Number and Survival

    PubMed Central

    Makhijani, Kalpana; Alexander, Brandy; Perrimon, Norbert; Brückner, Katja

    2015-01-01

    In multicellular organisms, cell number is typically determined by a balance of intracellular signals that positively and negatively regulate cell survival and proliferation. Dissecting these signaling networks facilitates the understanding of normal development and tumorigenesis. Here, we study signaling by the Drosophila PDGF/VEGF Receptor (Pvr) in embryonic blood cells (hemocytes) and in the related cell line Kc as a model for the requirement of PDGF/VEGF receptors in vertebrate cell survival and proliferation. The system allows the investigation of downstream and parallel signaling networks, based on the ability of Pvr to activate Ras/Erk, Akt/TOR, and yet-uncharacterized signaling pathway/s, which redundantly mediate cell survival and contribute to proliferation. Using Kc cells, we performed a genome wide RNAi screen for regulators of cell number in a sensitized, Pvr deficient background. We identified the receptor tyrosine kinase (RTK) Insulin-like receptor (InR) as a major Pvr Enhancer, and the nuclear hormone receptors Ecdysone receptor (EcR) and ultraspiracle (usp), corresponding to mammalian Retinoid X Receptor (RXR), as Pvr Suppressors. In vivo analysis in the Drosophila embryo revealed a previously unrecognized role for EcR to promote apoptotic death of embryonic blood cells, which is balanced with pro-survival signaling by Pvr and InR. Phosphoproteomic analysis demonstrates distinct modes of cell number regulation by EcR and RTK signaling. We define common phosphorylation targets of Pvr and InR that include regulators of cell survival, and unique targets responsible for specialized receptor functions. Interestingly, our analysis reveals that the selection of phosphorylation targets by signaling receptors shows qualitative changes depending on the signaling status of the cell, which may have wide-reaching implications for other cell regulatory systems. PMID:25749252

  14. Expert Assistant For A Clinical Hematology Blood Cell Analyzer

    NASA Astrophysics Data System (ADS)

    Young, Carole; Navlakha, Jainendra K.

    1989-03-01

    The COULTER COUNTER Model S Plus Series instruments are automated clinical hematology blood cell analyzers which measure the count, volume and population distribution of red blood cells, white blood cells and platelets, and hemoglobin from patient blood samples. In the clinical laboratory environment, instrument startup consists of a number of component and system checks to assure proper operation and calibration to insure reliable results are produced on patient samples. If a startup check fails, troubleshooting procedures are provided to assist the operator in determining the cause of the error. Troubleshooting requires expertise in instrument operation, troubleshooting procedures and evaluation of the data produced. This expert system is designed and developed to assist the startup diagnostics of COULTER COUNTER Model S Plus Series instruments. The system reads data produced by the instrument and validates it against expected values. If the values are not all correct, then the troubleshooting starts. Troubleshooting is handled for the most common subsystem problems and those which the operator has the equipment and knowledge to handle, problems that are cheapest to fix and problems that are quickest to fix. The expert system restarts the startup sequence whenever troubleshooting has been successful or recommends calling Customer Service when unsuccessful.

  15. Immune cells control skin lymphatic electrolyte homeostasis and blood pressure.

    PubMed

    Wiig, Helge; Schröder, Agnes; Neuhofer, Wolfgang; Jantsch, Jonathan; Kopp, Christoph; Karlsen, Tine V; Boschmann, Michael; Goss, Jennifer; Bry, Maija; Rakova, Natalia; Dahlmann, Anke; Brenner, Sven; Tenstad, Olav; Nurmi, Harri; Mervaala, Eero; Wagner, Hubertus; Beck, Franz-Xaver; Müller, Dominik N; Kerjaschki, Dontscho; Luft, Friedrich C; Harrison, David G; Alitalo, Kari; Titze, Jens

    2013-07-01

    The skin interstitium sequesters excess Na+ and Cl- in salt-sensitive hypertension. Mononuclear phagocyte system (MPS) cells are recruited to the skin, sense the hypertonic electrolyte accumulation in skin, and activate the tonicity-responsive enhancer-binding protein (TONEBP, also known as NFAT5) to initiate expression and secretion of VEGFC, which enhances electrolyte clearance via cutaneous lymph vessels and increases eNOS expression in blood vessels. It is unclear whether this local MPS response to osmotic stress is important to systemic blood pressure control. Herein, we show that deletion of TonEBP in mouse MPS cells prevents the VEGFC response to a high-salt diet (HSD) and increases blood pressure. Additionally, an antibody that blocks the lymph-endothelial VEGFC receptor, VEGFR3, selectively inhibited MPS-driven increases in cutaneous lymphatic capillary density, led to skin Cl- accumulation, and induced salt-sensitive hypertension. Mice overexpressing soluble VEGFR3 in epidermal keratinocytes exhibited hypoplastic cutaneous lymph capillaries and increased Na+, Cl-, and water retention in skin and salt-sensitive hypertension. Further, we found that HSD elevated skin osmolality above plasma levels. These results suggest that the skin contains a hypertonic interstitial fluid compartment in which MPS cells exert homeostatic and blood pressure-regulatory control by local organization of interstitial electrolyte clearance via TONEBP and VEGFC/VEGFR3-mediated modification of cutaneous lymphatic capillary function. PMID:23722907

  16. Flow of Red Blood Cells in Stenosed Microvessels

    NASA Astrophysics Data System (ADS)

    Vahidkhah, Koohyar; Balogh, Peter; Bagchi, Prosenjit

    2016-06-01

    A computational study is presented on the flow of deformable red blood cells in stenosed microvessels. It is observed that the Fahraeus-Lindqvist effect is significantly enhanced due to the presence of a stenosis. The apparent viscosity of blood is observed to increase by several folds when compared to non-stenosed vessels. An asymmetric distribution of the red blood cells, caused by geometric focusing in stenosed vessels, is observed to play a major role in the enhancement. The asymmetry in cell distribution also results in an asymmetry in average velocity and wall shear stress along the length of the stenosis. The discrete motion of the cells causes large time-dependent fluctuations in flow properties. The root-mean-square of flow rate fluctuations could be an order of magnitude higher than that in non-stenosed vessels. Several folds increase in Eulerian velocity fluctuation is also observed in the vicinity of the stenosis. Surprisingly, a transient flow reversal is observed upstream a stenosis but not downstream. The asymmetry and fluctuations in flow quantities and the flow reversal would not occur in absence of the cells. It is concluded that the flow physics and its physiological consequences are significantly different in micro- versus macrovascular stenosis.

  17. Flow of Red Blood Cells in Stenosed Microvessels.

    PubMed

    Vahidkhah, Koohyar; Balogh, Peter; Bagchi, Prosenjit

    2016-01-01

    A computational study is presented on the flow of deformable red blood cells in stenosed microvessels. It is observed that the Fahraeus-Lindqvist effect is significantly enhanced due to the presence of a stenosis. The apparent viscosity of blood is observed to increase by several folds when compared to non-stenosed vessels. An asymmetric distribution of the red blood cells, caused by geometric focusing in stenosed vessels, is observed to play a major role in the enhancement. The asymmetry in cell distribution also results in an asymmetry in average velocity and wall shear stress along the length of the stenosis. The discrete motion of the cells causes large time-dependent fluctuations in flow properties. The root-mean-square of flow rate fluctuations could be an order of magnitude higher than that in non-stenosed vessels. Several folds increase in Eulerian velocity fluctuation is also observed in the vicinity of the stenosis. Surprisingly, a transient flow reversal is observed upstream a stenosis but not downstream. The asymmetry and fluctuations in flow quantities and the flow reversal would not occur in absence of the cells. It is concluded that the flow physics and its physiological consequences are significantly different in micro- versus macrovascular stenosis. PMID:27319318

  18. Flow of Red Blood Cells in Stenosed Microvessels

    PubMed Central

    Vahidkhah, Koohyar; Balogh, Peter; Bagchi, Prosenjit

    2016-01-01

    A computational study is presented on the flow of deformable red blood cells in stenosed microvessels. It is observed that the Fahraeus-Lindqvist effect is significantly enhanced due to the presence of a stenosis. The apparent viscosity of blood is observed to increase by several folds when compared to non-stenosed vessels. An asymmetric distribution of the red blood cells, caused by geometric focusing in stenosed vessels, is observed to play a major role in the enhancement. The asymmetry in cell distribution also results in an asymmetry in average velocity and wall shear stress along the length of the stenosis. The discrete motion of the cells causes large time-dependent fluctuations in flow properties. The root-mean-square of flow rate fluctuations could be an order of magnitude higher than that in non-stenosed vessels. Several folds increase in Eulerian velocity fluctuation is also observed in the vicinity of the stenosis. Surprisingly, a transient flow reversal is observed upstream a stenosis but not downstream. The asymmetry and fluctuations in flow quantities and the flow reversal would not occur in absence of the cells. It is concluded that the flow physics and its physiological consequences are significantly different in micro- versus macrovascular stenosis. PMID:27319318

  19. Automatic analysis of microscopic images of red blood cell aggregates

    NASA Astrophysics Data System (ADS)

    Menichini, Pablo A.; Larese, Mónica G.; Riquelme, Bibiana D.

    2015-06-01

    Red blood cell aggregation is one of the most important factors in blood viscosity at stasis or at very low rates of flow. The basic structure of aggregates is a linear array of cell commonly termed as rouleaux. Enhanced or abnormal aggregation is seen in clinical conditions, such as diabetes and hypertension, producing alterations in the microcirculation, some of which can be analyzed through the characterization of aggregated cells. Frequently, image processing and analysis for the characterization of RBC aggregation were done manually or semi-automatically using interactive tools. We propose a system that processes images of RBC aggregation and automatically obtains the characterization and quantification of the different types of RBC aggregates. Present technique could be interesting to perform the adaptation as a routine used in hemorheological and Clinical Biochemistry Laboratories because this automatic method is rapid, efficient and economical, and at the same time independent of the user performing the analysis (repeatability of the analysis).

  20. Statistical analysis of dose heterogeneity in circulating blood: Implications for sequential methods of total body irradiation

    SciTech Connect

    Molloy, Janelle A.

    2010-11-15

    Purpose: Improvements in delivery techniques for total body irradiation (TBI) using Tomotherapy and intensity modulated radiation therapy have been proven feasible. Despite the promise of improved dose conformality, the application of these ''sequential'' techniques has been hampered by concerns over dose heterogeneity to circulating blood. The present study was conducted to provide quantitative evidence regarding the potential clinical impact of this heterogeneity. Methods: Blood perfusion was modeled analytically as possessing linear, sinusoidal motion in the craniocaudal dimension. The average perfusion period for human circulation was estimated to be approximately 78 s. Sequential treatment delivery was modeled as a Gaussian-shaped dose cloud with a 10 cm length that traversed a 183 cm patient length at a uniform speed. Total dose to circulating blood voxels was calculated via numerical integration and normalized to 2 Gy per fraction. Dose statistics and equivalent uniform dose (EUD) were calculated for relevant treatment times, radiobiological parameters, blood perfusion rates, and fractionation schemes. The model was then refined to account for random dispersion superimposed onto the underlying periodic blood flow. Finally, a fully stochastic model was developed using binomial and trinomial probability distributions. These models allowed for the analysis of nonlinear sequential treatment modalities and treatment designs that incorporate deliberate organ sparing. Results: The dose received by individual blood voxels exhibited asymmetric behavior that depended on the coherence among the blood velocity, circulation phase, and the spatiotemporal characteristics of the irradiation beam. Heterogeneity increased with the perfusion period and decreased with the treatment time. Notwithstanding, heterogeneity was less than {+-}10% for perfusion periods less than 150 s. The EUD was compromised for radiosensitive cells, long perfusion periods, and short treatment times

  1. Hemoglobin Aggregation in Single Red Blood Cells of Sickle Cell Anemia

    NASA Astrophysics Data System (ADS)

    Nishio, Izumi; Tanaka, Toyoichi; Sun, Shao-Tang; Imanishi, Yuri; Tsuyoshi Ohnishi, S.

    1983-06-01

    A laser light scattering technique was used to observe the extent of hemoglobin aggregation in solitary red blood cells of sickle cell anemia. Hemoglobin aggregation was confirmed in deoxygenated cells. The light scattering technique can also be applied to cytoplasmic studies of any biological cell.

  2. Classification of blood cells and tumor cells using label-free ultrasound and photoacoustics.

    PubMed

    Strohm, Eric M; Kolios, Michael C

    2015-08-01

    A label-free method that can identify cells in a blood sample using high frequency photoacoustic and ultrasound signals is demonstrated. When the wavelength of the ultrasound or photoacoustic wave is similar to the size of a single cell (frequencies of 100-500 MHz), unique periodic features occur within the ultrasound and photoacoustic power spectrum that depend on the cell size, structure, and morphology. These spectral features can be used to identify different cell types present in blood, such as red blood cells (RBCs), white blood cells (WBCs), and circulating tumor cells. Circulating melanoma cells are ideal for photoacoustic detection due to their endogenous optical absorption properties. Using a 532 nm pulsed laser and a 375 MHz transducer, the ultrasound and photoacoustic signals from RBCs, WBCs, and melanoma cells were individually measured in an acoustic microscope to examine how the signals change between cell types. A photoacoustic and ultrasound signal was detected from RBCs and melanoma cells; only an ultrasound signal was detected from WBCs. The different cell types were distinctly separated using the ultrasound and photoacoustic signal amplitude and power spectral periodicity. The size of each cell was also estimated from the spectral periodicity. For the first time, sound waves generated using pulse-echo ultrasound and photoacoustics have been used to identify and size single cells, with applications toward counting and identifying cells, including circulating melanoma cells. PMID:26079610

  3. A statistical model for red blood cell survival.

    PubMed

    Korell, Julia; Coulter, Carolyn V; Duffull, Stephen B

    2011-01-01

    A statistical model for the survival time of red blood cells (RBCs) with a continuous distribution of cell lifespans is presented. The underlying distribution of RBC lifespans is derived from a probability density function with a bathtub-shaped hazard curve, and accounts for death of RBCs due to senescence (age-dependent increasing hazard rate) and random destruction (constant hazard), as well as for death due to initial or delayed failures and neocytolysis (equivalent to early red cell mortality). The model yields survival times similar to those of previously published studies of RBC survival and is easily amenable to inclusion of drug effects and haemolytic disorders. PMID:20950630

  4. Fully functional NK cells after unrelated cord blood transplantation.

    PubMed

    Beziat, V; Nguyen, S; Lapusan, S; Hervier, B; Dhedin, N; Bories, D; Uzunov, M; Boudifa, A; Trebeden-Negre, H; Norol, F; Marjanovic, Z; Marie, J-P; Vernant, J-P; Debre, P; Rio, B; Vieillard, V

    2009-04-01

    Promising results of umbilical cord blood transplantation (UCBT) from unrelated donors have been reported in patients with hematologic disorders. These transplants, having potential to trigger beneficial donor-versus-recipient natural killer (NK) cell-mediated alloreaction, we have conducted the first extensive analysis of the phenotypic and functional properties of NK cells after UCBT. NK cells from 25 patients with high-risk hematologic malignancies were compared with cells derived from both healthy adult and CB cells. We found that following UCBT, NK cells display not only some phenotypic features associated with maturity but also unique characteristics that make them fully functional against leukemic blasts. We propose that this full functionality of alloreactive donor-derived NK may drive graft-versus-leukemia reactions after UCBT. PMID:19151772

  5. Expansion of regulatory T cells from umbilical cord blood and adult peripheral blood CD4(+)CD25 (+) T cells.

    PubMed

    Lin, Syh-Jae; Lu, Chun-Hao; Yan, Dah-Chin; Lee, Pei-Tzu; Hsiao, Hsiu-Shan; Kuo, Ming-Ling

    2014-10-01

    CD4(+)CD25(+) regulatory T cells (Treg), if properly expanded from umbilical cord blood (UCB), may provide a promising immunotherapeutic tool. Our previous data demonstrated that UCB CD4(+)CD25(+) T cells with 4-day stimulation have comparable phenotypes and suppressive function to that of adult peripheral blood (APB) CD4(+)CD25(+) T cells. We further examined whether 2-week culture would achieve higher expansion levels of Tregs. UCB CD4(+)CD25(+) T cells and their APB counterparts were stimulated with anti-CD3/anti-CD28 in the presence of IL-2 or IL-15 for 2 weeks. The cell proliferation and forkhead box P3 (FoxP3) expression were examined. The function of the expanded cells was then investigated by suppressive assay. IL-21 was applied to study whether it counteracts the function of UCB and APB CD4(+)CD25(+) T cells. The results indicate that UCB CD4(+)CD25(+) T cells expanded much better than their APB counterparts. IL-2 was superior to expand UCB and APB Tregs for 2 weeks than IL-15. FoxP3 expression which peaked on Day 10-14 was comparable. Most importantly, expanded UCB Tregs showed greater suppressive function in allogeneic mixed lymphocyte reaction. The addition of IL-21, however, counteracted the suppressive function of expanded UCB and APB Tregs. The results support using UCB as a source of Treg cells. PMID:24515612

  6. Characterization of red blood cells (RBCs) using dual Brillouin/Raman micro-spectroscopy

    NASA Astrophysics Data System (ADS)

    Meng, Zhaokai; Bustamante-Lopez, Sandra C.; Yakovlev, Vladislav V.; Meissner, Kenith E.

    2016-04-01

    Erythrocytes, or red blood cells, transport oxygen to and carbon dioxide from the body's tissues and organs. Red blood cell mechanical properties are altered in a number of diseases such as sickle cell anaemia and malaria. Additionally, mechanically modified red blood cell ghosts are being considered as a long-term, biocompatible carrier for drug delivery and for blood analyte sensing. Brillouin spectroscopy enables viscoelastic characterization of samples at the microscale. In this report, Brillouin spectroscopy is applied to characterize the mechanical properties of red blood cells and red blood cell ghosts.

  7. Cell-cell interaction in blood flow in patients with coronary heart disease (in vitro study)

    NASA Astrophysics Data System (ADS)

    Malinova, Lidia I.; Simonenko, Georgy V.; Denisova, Tatyana P.; Tuchin, Valery V.

    2007-02-01

    Blood cell-cell and cell-vessel wall interactions are one of the key patterns in blood and vascular pathophysiology. We have chosen the method of reconstruction of pulsative blood flow in vitro in the experimental set. Blood flow structure was studied by PC integrated video camera with following slide by slide analysis. Studied flow was of constant volumetric blood flow velocity (1 ml/h). Diameter of tube in use was comparable with coronary arteries diameter. Glucose solution and unfractured heparin were used as the nonspecial irritants of studied flow. Erythrocytes space structure in flow differs in all groups of patients in our study (men with stable angina pectoris (SAP), myocardial infarction (MI) and practically healthy men (PHM). Intensity of erythrocytes aggregate formation was maximal in patients with SAP, but time of their "construction/deconstruction" at glucose injection was minimal. Phenomena of primary clotting formation in patients with SAP of high function class was reconstructed under experimental conditions. Heparin injection (10 000 ED) increased linear blood flow velocity both in patients with SAP, MI and PHP but modulated the cell profile in the flow. Received data correspond with results of animal model studies and noninvasive blood flow studies in human. Results of our study reveal differences in blood flow structure in patients with coronary heart disease and PHP under irritating conditions as the possible framework of metabolic model of coronary blood flow destabilization.

  8. Bacterial glycosidases for the production of universal red blood cells.

    PubMed

    Liu, Qiyong P; Sulzenbacher, Gerlind; Yuan, Huaiping; Bennett, Eric P; Pietz, Greg; Saunders, Kristen; Spence, Jean; Nudelman, Edward; Levery, Steven B; White, Thayer; Neveu, John M; Lane, William S; Bourne, Yves; Olsson, Martin L; Henrissat, Bernard; Clausen, Henrik

    2007-04-01

    Enzymatic removal of blood group ABO antigens to develop universal red blood cells (RBCs) was a pioneering vision originally proposed more than 25 years ago. Although the feasibility of this approach was demonstrated in clinical trials for group B RBCs, a major obstacle in translating this technology to clinical practice has been the lack of efficient glycosidase enzymes. Here we report two bacterial glycosidase gene families that provide enzymes capable of efficient removal of A and B antigens at neutral pH with low consumption of recombinant enzymes. The crystal structure of a member of the alpha-N-acetylgalactosaminidase family reveals an unusual catalytic mechanism involving NAD+. The enzymatic conversion processes we describe hold promise for achieving the goal of producing universal RBCs, which would improve the blood supply while enhancing the safety of clinical transfusions. PMID:17401360

  9. Saving the leftovers: models for banking cord blood stem cells.

    PubMed

    Cogdell, Kimberly J

    2009-01-01

    Each year there are over four million live births in the United States. Each birth produces umbilical cord blood stem cells, which are usually discarded. The author argues that rather than discarding the umbilical cord, this valuable resource of cord blood should be banked and used for research and therapeutic purposes. Umbilical cord blood could provide a solution to the critical need to find matching donors for hematopoietic transplants in patients who have no matching bone marrow donors. Creating a system of universal donation to a public bank will greatlyincrease the number of donors and therefore, the number of matches for patients. Such a system will facilitate the development and use of new technologies and transplant procedures, while providing an opportunity for treatment to individuals who would otherwise not be able to find suitable donors. PMID:20101907

  10. Mobility Enhancement of Red Blood Cells with Biopolymers

    NASA Astrophysics Data System (ADS)

    Tahara, Daiki; Oikawa, Noriko; Kurita, Rei

    2016-03-01

    Adhesion of red blood cells (RBC) to substrates are one of crucial problems for a blood clot. Here we investigate the mobility of RBC between two glass substrates in saline with polymer systems. We find that RBCs are adhered to the glass substrate with PEG, however the mobility steeply increases with fibrinogen and dextran, which are biopolymers. We also find that the mobility affects an aggregation dynamics of RBCs, which is related with diseases such as influenza, blood clot and so on. The Brownian motion helps to increase probability of contact with each other and to find a more stable condition of the aggregation. Thus the biopolymers play important roles not only for preventing the adhesion but also for the aggregation.

  11. Image-based red cell counting for wild animals blood.

    PubMed

    Mauricio, Claudio R M; Schneider, Fabio K; Dos Santos, Leonilda Correia

    2010-01-01

    An image-based red blood cell (RBC) automatic counting system is presented for wild animals blood analysis. Images with 2048×1536-pixel resolution acquired on an optical microscope using Neubauer chambers are used to evaluate RBC counting for three animal species (Leopardus pardalis, Cebus apella and Nasua nasua) and the error found using the proposed method is similar to that obtained for inter observer visual counting method, i.e., around 10%. Smaller errors (e.g., 3%) can be obtained in regions with less grid artifacts. These promising results allow the use of the proposed method either as a complete automatic counting tool in laboratories for wild animal's blood analysis or as a first counting stage in a semi-automatic counting tool. PMID:21096766

  12. Cell salvage for minimising perioperative allogeneic blood transfusion

    PubMed Central

    Carless, Paul A; Henry, David A; Moxey, Annette J; O’Connell, Dianne; Brown, Tamara; Fergusson, Dean A

    2014-01-01

    Background Concerns regarding the safety of transfused blood have prompted reconsideration of the use of allogeneic (from an unrelated donor) red blood cell (RBC) transfusion, and a range of techniques to minimise transfusion requirements. Objectives To examine the evidence for the efficacy of cell salvage in reducing allogeneic blood transfusion and the evidence for any effect on clinical outcomes. Search methods We identified studies by searching CENTRAL (The Cochrane Library 2009, Issue 2), MEDLINE (1950 to June 2009), EMBASE (1980 to June 2009), the internet (to August 2009) and bibliographies of published articles. Selection criteria Randomised controlled trials with a concurrent control group in which adult patients, scheduled for non-urgent surgery, were randomised to cell salvage (autotransfusion) or to a control group who did not receive the intervention. Data collection and analysis Data were independently extracted and the risk of bias assessed. Relative risks (RR) and weighted mean differences (WMD) with 95% confidence intervals (CIs) were calculated. Data were pooled using a random-effects model. The primary outcomes were the number of patients exposed to allogeneic red cell transfusion and the amount of blood transfused. Other clinical outcomes are detailed in the review. Main results A total of 75 trials were included. Overall, the use of cell salvage reduced the rate of exposure to allogeneic RBC transfusion by a relative 38% (RR 0.62; 95% CI 0.55 to 0.70). The absolute reduction in risk (ARR) of receiving an allogeneic RBC transfusion was 21% (95% CI 15% to 26%). In orthopaedic procedures the RR of exposure to RBC transfusion was 0.46 (95% CI 0.37 to 0.57) compared to 0.77 (95% CI 0.69 to 0.86) for cardiac procedures. The use of cell salvage resulted in an average saving of 0.68 units of allogeneic RBC per patient (WMD −0.68; 95% CI −0.88 to −0.49). Cell salvage did not appear to impact adversely on clinical outcomes. Authors’ conclusions

  13. A system for counting fetal and maternal red blood cells.

    PubMed

    Ge, Ji; Gong, Zheng; Chen, Jun; Liu, Jun; Nguyen, John; Yang, Zongyi; Wang, Chen; Sun, Yu

    2014-12-01

    The Kleihauer-Betke (KB) test is the standard method for quantitating fetal-maternal hemorrhage in maternal care. In hospitals, the KB test is performed by a certified technologist to count a minimum of 2000 fetal and maternal red blood cells (RBCs) on a blood smear. Manual counting suffers from inherent inconsistency and unreliability. This paper describes a system for automated counting and distinguishing fetal and maternal RBCs on clinical KB slides. A custom-adapted hardware platform is used for KB slide scanning and image capturing. Spatial-color pixel classification with spectral clustering is proposed to separate overlapping cells. Optimal clustering number and total cell number are obtained through maximizing cluster validity index. To accurately identify fetal RBCs from maternal RBCs, multiple features including cell size, roundness, gradient, and saturation difference between cell and whole slide are used in supervised learning to generate feature vectors, to tackle cell color, shape, and contrast variations across clinical KB slides. The results show that the automated system is capable of completing the counting of over 60,000 cells (versus ∼2000 by technologists) within 5 min (versus ∼15 min by technologists). The throughput is improved by approximately 90 times compared to manual reading by technologists. The counting results are highly accurate and correlate strongly with those from benchmarking flow cytometry measurement. PMID:24879644

  14. Blood banking-induced alteration of red blood cell oxygen release ability

    PubMed Central

    Li, Yaojin; Xiong, Yanlian; Wang, Ruofeng; Tang, Fuzhou; Wang, Xiang

    2016-01-01

    Background Current blood banking procedures may not fully preserve red blood cell (RBC) function during storage, contributing to the decrease of RBC oxygen release ability. This study was undertaken to evaluate the impact of routine cold storage on RBC oxygen release ability. Materials and methods RBC units were collected from healthy donors and each unit was split into two parts (whole blood and suspended RBC) to exclude possible donor variability. Oxygen dissociation measurements were performed on blood units stored at 4 °C during a 5-week period. 2,3-diphosphoglycerate levels and fluorescent micrographs of erythrocyte band 3 were also analysed. Results P50 and oxygen release capacity decreased rapidly during the first 3 weeks, and then did not change significantly. In contrast, the kinetic properties (PO2-t curve and T*50) of oxygen release changed slowly during the first 3 weeks of storage, but then decreased significantly in the last 2 weeks. 2,3-diphosphoglycerate decreased quickly during the first 3 weeks of storage to almost undetectable levels. Band 3 aggregated significantly during the last 2 weeks of storage. Discussion RBC oxygen release ability appears to be sensitive to routine cold storage. The thermodynamic characteristics of RBC oxygen release ability changed mainly in the first 3 weeks of storage, due to the decrease of 2,3-diphosphoglycerate, whereas the kinetic characteristics of RBC oxygen release ability decreased significantly at the end of storage, probably affected by alterations of band 3. PMID:26674824

  15. 2-D Model for Normal and Sickle Cell Blood Microcirculation

    NASA Astrophysics Data System (ADS)

    Tekleab, Yonatan; Harris, Wesley

    2011-11-01

    Sickle cell disease (SCD) is a genetic disorder that alters the red blood cell (RBC) structure and function such that hemoglobin (Hb) cannot effectively bind and release oxygen. Previous computational models have been designed to study the microcirculation for insight into blood disorders such as SCD. Our novel 2-D computational model represents a fast, time efficient method developed to analyze flow dynamics, O2 diffusion, and cell deformation in the microcirculation. The model uses a finite difference, Crank-Nicholson scheme to compute the flow and O2 concentration, and the level set computational method to advect the RBC membrane on a staggered grid. Several sets of initial and boundary conditions were tested. Simulation data indicate a few parameters to be significant in the perturbation of the blood flow and O2 concentration profiles. Specifically, the Hill coefficient, arterial O2 partial pressure, O2 partial pressure at 50% Hb saturation, and cell membrane stiffness are significant factors. Results were found to be consistent with those of Le Floch [2010] and Secomb [2006].

  16. Blood group glycolipids as epithelial cell receptors for Candida albicans.

    PubMed Central

    Cameron, B J; Douglas, L J

    1996-01-01

    The role of glycosphingolipids as possible epithelial cell receptors for Candida albicans was examined by investigating the binding of biotinylated yeasts to lipids extracted from human buccal epithelial cells and separated on thin-layer chromatograms. Binding was visualized by the addition of 125I-streptavidin followed by autoradiography. Five C. albicans strains thought from earlier work to have a requirement for fucose-containing receptors all bound to the same three components in the lipid extract. A parallel chromatogram overlaid with biotinylated Ulex europaeus lectin, which is a fucose-binding lectin with a specificity for the H blood group antigen, showed that two of these glycosphingolipids carried this antigenic determinant. Preparations of crude and purified adhesin (a protein with a size of 15.7 kDa which lacked cysteine residues) from one of the strains also bound to these same two components. The third glycosphingolipid, which bound whole cells but neither preparation of adhesin, was recognized by Helix pomatia lectin, indicating that it contained N-acetylgalactosamine, possibly in the form of the A blood group antigen. Overlay assays with a sixth strain of C. albicans (GDH 2023) revealed a completely different binding pattern of four receptors, each of which contained N-acetylglucosamine. These results confirm earlier predictions about the receptor specificity of the strains made on the basis of adhesion inhibition studies and indicate that blood group antigens can act as epithelial cell receptors for C. albicans. PMID:8641797

  17. Nutritional status, metabolic changes and white blood cells in adolescents☆

    PubMed Central

    Oliveira, Thatianne Moreira Silva; de Faria, Franciane Rocha; de Faria, Eliane Rodrigues; Pereira, Patrícia Feliciano; Franceschini, Sylvia C.C.; Priore, Silvia Eloiza

    2014-01-01

    OBJECTIVE: To analyze the relationship between the peripheral blood white cells, metabolic changes, and nutritional status of adolescents with and without excess weight and body fat. METHODS: This cross-sectional study evaluated the body mass index (BMI) and percentage body fat (%BF) in 362 adolescents from 15 to 19 years of age, of both sexes. White blood cell count, platelet count, uric acid, fasting glucose, insulin, and lipid profile were measured. The inclusion criteria were agreement to participate in the study and signature of the informed consent. Exclusion criteria were: presence of chronic or infectious disease; use of medications that could cause changes in biochemical tests; pregnancy; participation in weight reduction and weight control programs; use of diuretics and laxatives; or the presence of a pacemaker. The following statistical tests were applied: Kolmogorov-Smirnov test, Student's t or Mann-Whitney test, Pearson or Spearman correlation tests, and chi-squared test, considering p<0.05. RESULTS: Overweight was observed in 20.7% of adolescents. The total cholesterol (TC) had a higher percentage of inadequacy (52.2%), followed by high-density lipoprotein (HDL) (38.4%). There was a positive correlation between white cells and serum lipids, insulin, body fat, and BMI. Monocytes were negatively correlated with BMI, and rods with BMI, body fat, and insulin. CONCLUSIONS: Nutritional status is related to an inflammatory process, and adolescents with excess weight or body fat presented higher amounts of white blood cells. PMID:25510999

  18. Laser viability method for red blood cell-state monitoring

    NASA Astrophysics Data System (ADS)

    Lapotko, Dmitry; Kuchinsky, Georgy; Antonishina, Elena; Scoromnik, Elena

    1996-01-01

    The method for RBC state control is based upon single cell viability control after illumination with laser pulse. Heat shock resulting from absorption of laser energy by a cell is considered as a cell load. This load acts from inside of the cell, is pulsed (10-5) and can be delivered directly to the chosen cells. The result of each illumination as cell survival or damage is controlled optically by monitoring the cells' response on a pulse through photothermal technique. Under fixed laser parameters the percentage of damaged cells is viability index (VI) for a certain cell population. The testing procedure includes consequential illumination of each cell in population and calculation of VI. Experimental set up is based upon optical microscope. Dual laser thermal lens technique is used for cell illumination and monitoring. For cell loading 5 ns pulses, 400 divided by 600 nm with energies up to 20 (mu) J are generated by tunable dye laser. Cell monitoring is realized with cw He-Ne (632.8 nm) laser and photodetector. All data acquisition routines are automated. Up to 3 cell suspensions can be studied in a multisample chamber designed to secure cells. An amount of cell suspension required is 1 (mu) l. One population test at a fixed wavelength takes 2 divided by 3 min. In experiments with rats, treated with LPS E. Coli injection to stimulate fever and a septic stress we found that variation of RBC viability becomes apparent in 20 - 30 min after injection, while the clinical changes (blood pressure, body temperature, skin temperature) become detectable after 1 hour. The results obtained show that the method can reveal additional properties of the cells most abundant for monitoring and diagnostic tasks.

  19. Red Blood Cell Polymorphism and Susceptibility to Plasmodium vivax

    PubMed Central

    Zimmerman, Peter A.; Ferreira, Marcelo U.; Howes, Rosalind E.; Mercereau-Puijalon, Odile

    2013-01-01

    Resistance to Plasmodium vivax blood-stage infection has been widely recognised to result from absence of the Duffy (Fy) blood group from the surface of red blood cells (RBCs) in individuals of African descent. Interestingly, recent studies from different malaria-endemic regions have begun to reveal new perspectives on the association between Duffy gene polymorphism and P. vivax malaria. In Papua New Guinea and the Americas, heterozygous carriers of a Duffy-negative allele are less susceptible to P. vivax infection than Duffy-positive homozygotes. In Brazil, studies show that the Fya antigen, compared to Fyb, is associated with lower binding to the P. vivax Duffy-binding protein and reduced susceptibility to vivax malaria. Additionally, it is interesting that numerous studies have now shown that P. vivax can infect RBCs and cause clinical disease in Duffy-negative people. This suggests that the relationship between P. vivax and the Duffy antigen is more complex than customarily described. Evidence of P. vivax Duffy-independent red cell invasion indicates that the parasite must be evolving alternative red cell invasion pathways. In this chapter, we review the evidence for P. vivax Duffy-dependent and Duffy-independent red cell invasion. We also consider the influence of further host gene polymorphism associated with malaria endemicity on susceptibility to vivax malaria. The interaction between the parasite and the RBC has significant potential to influence the effectiveness of P. vivax-specific vaccines and drug treatments. Ultimately, the relationships between red cell polymorphisms and P. vivax blood-stage infection will influence our estimates on the population at risk and efforts to eliminate vivax malaria. PMID:23384621

  20. Red Cell Properties after Different Modes of Blood Transportation

    PubMed Central

    Makhro, Asya; Huisjes, Rick; Verhagen, Liesbeth P.; Mañú-Pereira, María del Mar; Llaudet-Planas, Esther; Petkova-Kirova, Polina; Wang, Jue; Eichler, Hermann; Bogdanova, Anna; van Wijk, Richard; Vives-Corrons, Joan-Lluís; Kaestner, Lars

    2016-01-01

    Transportation of blood samples is unavoidable for assessment of specific parameters in blood of patients with rare anemias, blood doping testing, or for research purposes. Despite the awareness that shipment may substantially alter multiple parameters, no study of that extent has been performed to assess these changes and optimize shipment conditions to reduce transportation-related artifacts. Here we investigate the changes in multiple parameters in blood of healthy donors over 72 h of simulated shipment conditions. Three different anticoagulants (K3EDTA, Sodium Heparin, and citrate-based CPDA) for two temperatures (4°C and room temperature) were tested to define the optimal transportation conditions. Parameters measured cover common cytology and biochemistry parameters (complete blood count, hematocrit, morphological examination), red blood cell (RBC) volume, ion content and density, membrane properties and stability (hemolysis, osmotic fragility, membrane heat stability, patch-clamp investigations, and formation of micro vesicles), Ca2+ handling, RBC metabolism, activity of numerous enzymes, and O2 transport capacity. Our findings indicate that individual sets of parameters may require different shipment settings (anticoagulants, temperature). Most of the parameters except for ion (Na+, K+, Ca2+) handling and, possibly, reticulocytes counts, tend to favor transportation at 4°C. Whereas plasma and intraerythrocytic Ca2+ cannot be accurately measured in the presence of chelators such as citrate and EDTA, the majority of Ca2+-dependent parameters are stabilized in CPDA samples. Even in blood samples from healthy donors transported using an optimized shipment protocol, the majority of parameters were stable within 24 h, a condition that may not hold for the samples of patients with rare anemias. This implies for as short as possible shipping using fast courier services to the closest expert laboratory at reach. Mobile laboratories or the travel of the patients to

  1. Red Cell Properties after Different Modes of Blood Transportation.

    PubMed

    Makhro, Asya; Huisjes, Rick; Verhagen, Liesbeth P; Mañú-Pereira, María Del Mar; Llaudet-Planas, Esther; Petkova-Kirova, Polina; Wang, Jue; Eichler, Hermann; Bogdanova, Anna; van Wijk, Richard; Vives-Corrons, Joan-Lluís; Kaestner, Lars

    2016-01-01

    Transportation of blood samples is unavoidable for assessment of specific parameters in blood of patients with rare anemias, blood doping testing, or for research purposes. Despite the awareness that shipment may substantially alter multiple parameters, no study of that extent has been performed to assess these changes and optimize shipment conditions to reduce transportation-related artifacts. Here we investigate the changes in multiple parameters in blood of healthy donors over 72 h of simulated shipment conditions. Three different anticoagulants (K3EDTA, Sodium Heparin, and citrate-based CPDA) for two temperatures (4°C and room temperature) were tested to define the optimal transportation conditions. Parameters measured cover common cytology and biochemistry parameters (complete blood count, hematocrit, morphological examination), red blood cell (RBC) volume, ion content and density, membrane properties and stability (hemolysis, osmotic fragility, membrane heat stability, patch-clamp investigations, and formation of micro vesicles), Ca(2+) handling, RBC metabolism, activity of numerous enzymes, and O2 transport capacity. Our findings indicate that individual sets of parameters may require different shipment settings (anticoagulants, temperature). Most of the parameters except for ion (Na(+), K(+), Ca(2+)) handling and, possibly, reticulocytes counts, tend to favor transportation at 4°C. Whereas plasma and intraerythrocytic Ca(2+) cannot be accurately measured in the presence of chelators such as citrate and EDTA, the majority of Ca(2+)-dependent parameters are stabilized in CPDA samples. Even in blood samples from healthy donors transported using an optimized shipment protocol, the majority of parameters were stable within 24 h, a condition that may not hold for the samples of patients with rare anemias. This implies for as short as possible shipping using fast courier services to the closest expert laboratory at reach. Mobile laboratories or the travel of the

  2. Endometrial Mesenchymal Stem Cells Isolated from Menstrual Blood by Adherence

    PubMed Central

    Du, Xue; Yuan, Qing; Qu, Ye; Zhou, Yuan; Bei, Jia

    2016-01-01

    Objective. To find a convenient and efficient way to isolate MSCs from human menstrual blood and to investigate their biological characteristics, proliferative capacity, and secretion levels. Methods. MSCs were isolated from menstrual blood of 3 healthy women using adherence. Cell immunological phenotype was examined by flow cytometry; the adipogenic, osteogenic, and chondrogenic differentiation of MSCs was examined by Oil-Red-O staining, ALP staining, and Alcian Blue staining, respectively; and the secretion of cytokines, including vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), and insulin-like growth factor-1 (IGF-1), was detected using enzyme-linked immunosorbent assay. Results. MB-MSCs were successfully isolated from human menstrual blood using adherence. They were positive for CD73, CD105, CD29, and CD44, but negative for CD31 and CD45. The differentiated MB-MSCs were positive for ALP staining, Oil-Red-O staining, and Alcian Blue staining. In addition, they could secrete antiapoptotic cytokines, such as VEGF, IGF-1, and HGF. Conclusion. It is feasible to isolate MSCs from human menstrual blood, thus avoiding invasive procedures and ethical controversies. Adherence could be a promising alternative to the density gradient centrifugation for the isolation of MSCs from menstrual blood. PMID:26681948

  3. Disruption of astrocyte-vascular coupling and the blood-brain barrier by invading glioma cells

    PubMed Central

    Watkins, Stacey; Robel, Stefanie; Kimbrough, Ian F.; Robert, Stephanie M.; Ellis-Davies, Graham; Sontheimer, Harald

    2014-01-01

    Astrocytic endfeet cover the entire cerebral vasculature and serve as exchange sites for ions, metabolites, and energy substrates from the blood to the brain. They maintain endothelial tight junctions that form the blood-brain barrier (BBB) and release vasoactive molecules that regulate vascular tone. Malignant gliomas are highly invasive tumors that use the perivascular space for invasion and co-opt existing vessels as satellite tumors form. Here we use a clinically relevant mouse model of glioma and find that glioma cells, as they populate the perivascular space of pre-existing vessels, displace astrocytic endfeet from endothelial or vascular smooth muscle cells. This causes a focal breach in the BBB. Furthermore, astrocyte-mediated gliovascular coupling is lost, and glioma cells seize control over regulation of vascular tone through Ca2+-dependent release of K+. These findings have important clinical implications regarding blood flow in the tumor-associated brain and the ability to locally deliver chemotherapeutic drugs in disease. PMID:24943270

  4. Mathematical model of peripheral blood stem cell harvest kinetics.

    PubMed

    Mayer, J; Pospísil, Z; Korístek, Z

    2003-10-01

    A mathematical model of peripheral blood stem cell harvests was developed, taking two new parameters R (number of recruited cells/minute) and E(f) (efficiency of collection) into consideration in addition to concentrations and collected amounts of cells. This model was tested on 241 harvest procedures in cancer patients (chemotherapy+G-CSF stimulation), donors of allogeneic PBSC, and platelet donors, using different collection procedures, with a Cobe Spectra Cell separator. The relationships between preapheresis concentrations, R, E(f) and harvested amounts of cells were complex, and different for different harvest procedures and populations of donors. However, invariably, recruitment played an important role and contributed significantly to the final harvest in all types of cells studied. For example, for the patient group, mean recruitment was 1.3 x 10(6) CD34+ cells/min and the amount of recruited cells corresponded to 65% of all collected cells. Recruitment was significantly influenced by pretreatment with chemo-therapy and/or radiotherapy. The mean recruitment values for the subgroups with limited, moderate, and extensive pretreatment were 1.65 x 10(6), 0.87 x 10(6), and 0.32 x 10(6) CD34+ cells released per minute, respectively. The finding of a quick and massive recruitment phenomenon may stimulate further research into hematopoiesis in order to maximize harvested cells. PMID:14520417

  5. Effect of blood storage on erythrocyte/wall interactions: implications for surface charge and rigidity.

    PubMed

    Godin, C; Caprani, A

    1997-01-01

    In this report, we study, under flow conditions, the interactions of stored erythrocytes with an artificial surface: a microelectrode whose charge density ranges from -15 to +27 microC/cm2. Interactions consist of red cells slowly circulating on the microelectrode and exerting a real contact with the electrode. Interaction is detected and measured by transient fluctuations of the electrolyte resistance obtained by impedance measurement of the microelectrode. Effects of aging induced by storage of whole blood at 4 degrees C show that the surface charge of erythrocytes rapidly decreases when blood is stored for more than 6 days under our experimental conditions. In comparison with trypsin-treated erythrocytes, an eight day storage induces a 60% decrease in the surface charge of red cells. After two weeks of storage, red cells are no longer negatively charged, presumably because of removal of sialic acid. Cells rigidity is significant after 6 days of storage and influences the electrical contact. Membrane rigidity increase could arise from the surface charge decrease. Finally the surface charge decrease could be importance in the use of stored blood. PMID:9232845

  6. Reduction of prion infectivity in packed red blood cells

    SciTech Connect

    Morales, Rodrigo; Buytaert-Hoefen, Kimberley A.; Gonzalez-Romero, Dennisse; Castilla, Joaquin; Hansen, Eric T.; Hlavinka, Dennis; Goodrich, Raymond P.; Soto, Claudio

    2008-12-12

    The link between a new variant form of Creutzfeldt-Jakob disease (vCJD) and the consumption of prion contaminated cattle meat as well as recent findings showing that vCJD can be transmitted by blood transfusion have raised public health concerns. Currently, a reliable test to identify prions in blood samples is not available. The purpose of this study was to evaluate the possibility to remove scrapie prion protein (PrP{sup Sc}) and infectivity from red blood cell (RBC) suspensions by a simple washing procedure using a cell separation and washing device. The extent of prion removal was assessed by Western blot, PMCA and infectivity bioassays. Our results revealed a substantial removal of infectious prions ({>=}3 logs of infectivity) by all techniques used. These data suggest that a significant amount of infectivity present in RBC preparations can be removed by a simple washing procedure. This technology may lead to increased safety of blood products and reduce the risk of further propagation of prion diseases.

  7. Blood based cell biopsy for early detection of cancer

    NASA Astrophysics Data System (ADS)

    Tang, Cha-Mei; Adams, Daniel; Adams, Diane; Alpaugh, R. Katherine; Cristofanilli, Massimo; Martin, Stuart; Chumsri, Saranya; Marks, Jeffrey

    Early detection (ED) of cancer holds the promise for less aggressive treatments and better outcome. However, there are few accepted methods for ED. We report on a previously unknown blood cell found specifically in the peripheral blood of many solid tumors. They are defined as Cancer Associated Macrophage-Like cells (CAMLs) and are characterized by large size (25-300 μm) and expression of cancer markers. CAMLs were isolated on precision filters during blood filtration. We conducted prospective studies in breast cancer (BC) to ascertain CAML prevalence, specificity and sensitivity in relation to disease status at clinical presentation. We report on two related but separate studies: 1) the isolation of CAMLs from patients with known invasive BC, compared to healthy volunteers and, 2) a double blind study conducted on women undergoing core needle biopsy to evaluate suspicious breast masses. The studies show that CAMLs are found in all stages of BC and suggest that detection of CAMLs can differentiate patients with BC from those with benign breast conditions and healthy individuals. This non-invasive blood test can be potentially used for ED of BC and other malignancies after validation studies with the advantage of a minimally invasive procedure and longitudinal monitoring. This work was supported by Grants from Maryland TEDCO MTTCF, R01-CA154624 from NIH, KG100240 from Susan G. Komen Foundation, Era of Hope Scholar award from DoD (BC100675), and U01-CA084955 from NCI EDRN.

  8. Aging: a portrait from gene expression profile in blood cells.

    PubMed

    Calabria, Elisa; Mazza, Emilia Maria Cristina; Dyar, Kenneth Allen; Pogliaghi, Silvia; Bruseghini, Paolo; Morandi, Carlo; Salvagno, Gian Luca; Gelati, Matteo; Guidi, Gian Cesare; Bicciato, Silvio; Schiaffino, Stefano; Schena, Federico; Capelli, Carlo

    2016-08-01

    The availability of reliable biomarkers of aging is important not only to monitor the effect of interventions and predict the timing of pathologies associated with aging but also to understand the mechanisms and devise appropriate countermeasures. Blood cells provide an easily available tissue and gene expression profiles from whole blood samples appear to mirror disease states and some aspects of the aging process itself. We report here a microarray analysis of whole blood samples from two cohorts of healthy adult and elderly subjects, aged 43±3 and 68±4 years, respectively, to monitor gene expression changes in the initial phase of the senescence process. A number of significant changes were found in the elderly compared to the adult group, including decreased levels of transcripts coding for components of the mitochondrial respiratory chain, which correlate with a parallel decline in the maximum rate of oxygen consumption (VO2max), as monitored in the same subjects. In addition, blood cells show age-related changes in the expression of several markers of immunosenescence, inflammation and oxidative stress. These findings support the notion that the immune system has a major role in tissue homeostasis and repair, which appears to be impaired since early stages of the aging process. PMID:27545843

  9. Enhancement of red blood cell aggregation by plasma triglycerides.

    PubMed

    Cicha, I; Suzuki, Y; Tateishi, N; Maeda, N

    2001-01-01

    The effects of plasma triglycerides level on human red blood cells (RBCs) indices, hematological parameters, RBCs aggregation velocity and whole blood viscosity were studied at 2 hours after high-fat or low-fat meal. Proteins, triglycerides and cholesterol levels of plasma were analysed. The RBCs rouleaux formation rate was measured in 70% autologous plasma (with 30% phosphate-buffered saline, PBS) or 1 g/dl dextran T70 solution (with 4 g/dl bovine serum albumin) in PBS, using a low-shear rheoscope. The results were grouped according to triglycerides content in plasma. No significant difference in whole blood viscosity, hematological parameters, RBC indices, protein and cholesterol content was observed between high-fat and low-fat blood samples. There was a significant increase in rouleaux formation rate of samples with high triglyceride levels, when measured in 70% autologous plasma, but it was not significant in dextran T70 containing medium. In conclusion, the results obtained suggest that alteration of plasma lipid levels as well as possible changes in the cell membrane lipid composition lead to enhanced RBC aggregation. PMID:11564913

  10. Continuous-flow microfluidic blood cell sorting for unprocessed whole blood using surface-micromachined microfiltration membranes.

    PubMed

    Li, Xiang; Chen, Weiqiang; Liu, Guangyu; Lu, Wei; Fu, Jianping

    2014-07-21

    White blood cells (WBCs) constitute about 0.1% of the blood cells, yet they play a critical role in innate and adaptive immune responses against pathogenic infections, allergic conditions, and malignancies and thus contain rich information about the immune status of the body. Rapid isolation of WBCs directly from whole blood is a prerequisite for any integrated immunoassay platform designed for examining WBC phenotypes and functions; however, such functionality is still challenging for blood-on-a-chip systems, as existing microfluidic cell sorting techniques are inadequate for efficiently processing unprocessed whole blood on chip with concurrent high throughput and cell purity. Herein we report a microfluidic chip for continuous-flow isolation and sorting of WBCs from whole blood with high throughput and separation efficiency. The microfluidic cell sorting chip leveraged the crossflow filtration scheme in conjunction with a surface-micromachined poly(dimethylsiloxane) (PDMS) microfiltration membrane (PMM) with high porosity. With a sample throughput of 1 mL h(-1), the microfluidic cell sorting chip could recover 27.4 ± 4.9% WBCs with a purity of 93.5 ± 0.5%. By virtue of its separation efficiency, ease of sample recovery, and high throughput enabled by its continuous-flow operation, the microfluidic cell sorting chip holds promise as an upstream component for blood sample preparation and analysis in integrated blood-on-a-chip systems. PMID:24895109

  11. Continuous-flow microfluidic blood cell sorting for unprocessed whole blood using surface-micromachined microfiltration membranes

    PubMed Central

    Li, Xiang; Chen, Weiqiang; Liu, Guangyu; Lu, Wei; Fu, Jianping

    2014-01-01

    White blood cells (WBCs) constitute about 0.1% of the blood cells, yet they play a critical role in innate and adaptive immune responses against pathogenic infections, allergic conditions, and malignancies and thus contain rich information about the immune status of the body. Rapid isolation of WBCs directly from whole blood is a prerequisite for any integrated immunoassay platform designed for examining WBC phenotypes and functions; however, such functionality is still challenging for blood-on-a-chip systems, as existing microfluidic cell sorting techniques are inadequate for efficiently processing unprocessed whole blood on chip with concurrent high throughput and cell purity. Herein we report a microfluidic chip for continuous-flow isolation and sorting of WBCs from whole blood with high throughput and separation efficiency. The microfluidic cell sorting chip leveraged the crossflow filtration scheme in conjunction with a surface-micromachined poly(dimethylsiloxane) (PDMS) microfiltration membrane (PMM) with high porosity. With a sample throughput of 1 mL hr−1, the microfluidic cell sorting chip could recover 27.4 ± 4.9% WBCs with a purity of 93.5 ± 0.5%. By virtue of its separation efficiency, ease of sample recovery, and high throughput enabled by its continuous-flow operation, the microfluidic cell sorting chip holds promise as an upstream component for blood sample preparation and analysis in integrated blood-on-a-chip systems. PMID:24895109

  12. Computer-Aided Diagnosis Of Leukemic Blood Cells

    NASA Astrophysics Data System (ADS)

    Gunter, U.; Harms, H.; Haucke, M.; Aus, H. M.; ter Meulen, V.

    1982-11-01

    In a first clinical test, computer programs are being used to diagnose leukemias. The data collected include blood samples from patients suffering from acute myelomonocytic-, acute monocytic- and acute promyelocytic, myeloblastic, prolymphocytic, chronic lymphocytic leukemias and leukemic transformed immunocytoma. The proper differentiation of the leukemic cells is essential because the therapy depends on the type of leukemia. The algorithms analyse the fine chromatin texture and distribution in the nuclei as well as size and shape parameters from the cells and nuclei. Cells with similar nuclei from different leukemias can be distinguished from each other by analyzing the cell cytoplasm images. Recognition of these subtle differences in the cells require an image sampling rate of 15-30 pixel/micron. The results for the entire data set correlate directly to established hematological parameters and support the previously published initial training set .

  13. Shape anisotropy induces rotations in optically trapped red blood cells

    NASA Astrophysics Data System (ADS)

    Bambardekar, Kapil; Dharmadhikari, Jayashree A.; Dharmadhikari, Aditya K.; Yamada, Toshihoro; Kato, Tsuyoshi; Kono, Hirohiko; Fujimura, Yuichi; Sharma, Shobhona; Mathur, Deepak

    2010-07-01

    A combined experimental and theoretical study is carried out to probe the rotational behavior of red blood cells (RBCs) in a single beam optical trap. We induce shape changes in RBCs by altering the properties of the suspension medium in which live cells float. We find that certain shape anisotropies result in the rotation of optically trapped cells. Indeed, even normal (healthy) RBCs can be made to rotate using linearly polarized trapping light by altering the osmotic stress the cells are subjected to. Hyperosmotic stress is found to induce shape anisotropies. We also probe the effect of the medium's viscosity on cell rotation. The observed rotations are modeled using a Langevin-type equation of motion that takes into account frictional forces that are generated as RBCs rotate in the medium. We observe good correlation between our measured data and calculated results.

  14. Blood transcriptional signature of recombinant human erythropoietin administration and implications for antidoping strategies.

    PubMed

    Durussel, Jérôme; Haile, Diresibachew W; Mooses, Kerli; Daskalaki, Evangelia; Beattie, Wendy; Mooses, Martin; Mekonen, Wondyefraw; Ongaro, Neford; Anjila, Edwin; Patel, Rajan K; Padmanabhan, Neal; McBride, Martin W; McClure, John D; Pitsiladis, Yannis P

    2016-03-01

    Recombinant human erythropoietin (rHuEPO) is frequently abused by athletes as a performance-enhancing drug, despite being prohibited by the World Anti-Doping Agency. Although the methods to detect blood doping, including rHuEPO injections, have improved in recent years, they remain imperfect. In a proof-of-principle study, we identified, replicated, and validated the whole blood transcriptional signature of rHuEPO in endurance-trained Caucasian males at sea level (n = 18) and Kenyan endurance runners at moderate altitude (n = 20), all of whom received rHuEPO injections for 4 wk. Transcriptional profiling shows that hundreds of transcripts were altered by rHuEPO in both cohorts. The main regulated expression pattern, observed in all participants, was characterized by a "rebound" effect with a profound upregulation during rHuEPO and a subsequent downregulation up to 4 wk postadministration. The functions of the identified genes were mainly related to the functional and structural properties of the red blood cell. Of the genes identified to be differentially expressed during and post-rHuEPO, we further confirmed a whole blood 34-transcript signature that can distinguish between samples collected pre-, during, and post-rHuEPO administration. By providing biomarkers that can reveal rHuEPO use, our findings represent an advance in the development of new methods for the detection of blood doping. PMID:26757800

  15. Isolation of human monoclonal antibodies from peripheral blood B cells.

    PubMed

    Huang, Jinghe; Doria-Rose, Nicole A; Longo, Nancy S; Laub, Leo; Lin, Chien-Li; Turk, Ellen; Kang, Byong H; Migueles, Stephen A; Bailer, Robert T; Mascola, John R; Connors, Mark

    2013-10-01

    Isolation of monoclonal antibodies is an important technique for understanding the specificities and characteristics of antibodies that underlie the humoral immune response to a given antigen. Here we describe a technique for isolating monoclonal antibodies from human peripheral blood mononuclear cells. The protocol includes strategies for the isolation of switch-memory B cells from peripheral blood, the culture of B cells, the removal of the supernatant for screening and the lysis of B cells in preparation for immunoglobulin heavy-chain and light-chain amplification and cloning. We have observed that the addition of cytokines IL-2, IL-21 and irradiated 3T3-msCD40L feeder cells can successfully stimulate switch-memory B cells to produce high concentrations of IgG in the supernatant. The supernatant may then be screened by appropriate assays for binding or for other functions. This protocol can be completed in 2 weeks. It is adaptable to use in other species and enables the efficient isolation of antibodies with a desired functional characteristic without prior knowledge of specificity. PMID:24030440

  16. Increased B Cell and Cytotoxic NK Cell Proportions and Increased T Cell Responsiveness in Blood of Natalizumab-Treated Multiple Sclerosis Patients

    PubMed Central

    Jenmalm, Maria C.; Dahle, Charlotte; Vrethem, Magnus; Ernerudh, Jan

    2013-01-01

    Background Changes in the blood lymphocyte composition probably both mediate and reflect the effects of natalizumab treatment in multiple sclerosis, with implications for treatment benefits and risks. Methods A broad panel of markers for lymphocyte populations, including states of activation and co-stimulation, as well as functional T cell responses to recall antigens and mitogens, were assessed by flow cytometry in 40 patients with relapsing multiple sclerosis before and after one-year natalizumab treatment. Results Absolute numbers of all major lymphocyte populations increased after treatment, most markedly for NK and B cells. The fraction of both memory and presumed regulatory B cell subsets increased, as did CD3-CD56dim cytotoxic NK cells, whereas CD3-CD56bright regulatory NK cells decreased. The increase in cell numbers was further associated with a restored T cell responsiveness to recall antigens and mitogens in functional assays. Conclusions Our data confirms that natalizumab treatment increases the number of lymphocytes in blood, likely mirroring the expression of VLA-4 being highest on NK and B cells. This finding supports reduction of lymphocyte extravasation as a main mode of action, although the differential effects on subpopulation composition suggests that cell-signalling may also be affected. The systemic increase in T cell responsiveness reflects the increase in numbers, and while augmenting anti-infectious responses systemically, localized responses may become correspondingly decreased. PMID:24312575

  17. Red Blood Cells Motion in a Glass Microchannel

    NASA Astrophysics Data System (ADS)

    Pinho, Diana; Pereira, Ana I.; Lima, Rui

    2010-09-01

    The motion of the red blood cells (RBCs) flowing in microvessels and microchannels depend on several effects, such as hematocrit (Hct), geometry, and temperature. According to our knowledge, the effect of the temperature on RBC motion was never investigated at a microscale level. Hence, the aim of the present work is to determine the effect of the temperature on the RBC's trajectories and to investigate the best approximation of the trajectories through a nonlinear optimization. In vitro human blood was pumped through a 100 μm circular microchannel and by using a confocal micro-PTV system the RBC's trajectories were measured at different temperatures, i.e., 25° C and 37° C. In this study we measured the motion of forty cells flowing in the middle of the microchannel and applied different functions to approximate its behavior.

  18. Analyzing Illumina Gene Expression Microarray Data Obtained From Human Whole Blood Cell and Blood Monocyte Samples.

    PubMed

    Teumer, Alexander; Schurmann, Claudia; Schillert, Arne; Schramm, Katharina; Ziegler, Andreas; Prokisch, Holger

    2016-01-01

    Microarray profiling of gene expression is widely applied to studies in molecular biology and functional genomics. Experimental and technical variations make not only the statistical analysis of single studies but also meta-analyses of different studies very challenging. Here, we describe the analytical steps required to substantially reduce the variations of gene expression data without affecting true effect sizes. A software pipeline has been established using gene expression data from a total of 3358 whole blood cell and blood monocyte samples, all from three German population-based cohorts, measured on the Illumina HumanHT-12 v3 BeadChip array. In summary, adjustment for a few selected technical factors greatly improved reliability of gene expression analyses. Such adjustments are particularly required for meta-analyses of different studies. PMID:26614070

  19. Leukemia cell microvesicles promote survival in umbilical cord blood hematopoietic stem cells

    PubMed Central

    Razmkhah, Farnaz; Soleimani, Masoud; Mehrabani, Davood; Karimi, Mohammad Hossein; Kafi-abad, Sedigheh Amini

    2015-01-01

    Microvesicles can transfer their contents, proteins and RNA, to target cells and thereby transform them. This may induce apoptosis or survival depending on cell origin and the target cell. In this study, we investigate the effect of leukemic cell microvesicles on umbilical cord blood hematopoietic stem cells to seek evidence of apoptosis or cell survival. Microvesicles were isolated from both healthy donor bone marrow samples and Jurkat cells by ultra-centrifugation and were added to hematopoietic stem cells sorted from umbilical cord blood samples by magnetic associated cell sorting (MACS) technique. After 7 days, cell count, cell viability, flow cytometry analysis for hematopoietic stem cell markers and qPCR for P53 gene expression were performed. The results showed higher cell number, higher cell viability rate and lower P53 gene expression in leukemia group in comparison with normal and control groups. Also, CD34 expression as the most important hematopoietic stem cell marker, did not change during the treatment and lineage differentiation was not observed. In conclusion, this study showed anti-apoptotic effect of leukemia cell derived microvesicles on umbilical cord blood hematopoietic stem cells. PMID:26862318

  20. Peripheral red blood cell split chimerism as a consequence of intramedullary selective apoptosis of recipient red blood cells in a case of sickle cell disease.

    PubMed

    Marziali, Marco; Isgrò, Antonella; Sodani, Pietro; Gaziev, Javid; Fraboni, Daniela; Paciaroni, Katia; Gallucci, Cristiano; Alfieri, Cecilia; Roveda, Andrea; De Angelis, Gioia; Cardarelli, Luisa; Ribersani, Michela; Andreani, Marco; Lucarelli, Guido

    2014-01-01

    Allogeneic cellular gene therapy through hematopoietic stem cell transplantation is the only radical cure for congenital hemoglobinopathies like thalassemia and sickle cell anemia. Persistent mixed hematopoietic chimerism (PMC) has been described in thalassemia and sickle cell anemia. Here, we describe the clinical course of a 6-year-old girl who had received bone marrow transplant for sickle cell anemia. After the transplant, the patient showed 36% donor hematopoietic stem cells in the bone marrow, whereas in the peripheral blood there was evidence of 80% circulating donor red blood cells (RBC). The analysis of apoptosis at the Bone Marrow level suggests that Fas might contribute to the cell death of host erythroid precursors. The increase in NK cells and the regulatory T cell population observed in this patient suggests that these cells might contribute to the condition of mixed chimerism. PMID:25408852

  1. Peripheral Red Blood Cell Split Chimerism as a Consequence of Intramedullary Selective Apoptosis of Recipient Red Blood Cells in a Case of Sickle Cell Disease

    PubMed Central

    Marziali, Marco; Isgrò, Antonella; Sodani, Pietro; Gaziev, Javid; Fraboni, Daniela; Paciaroni, Katia; Gallucci, Cristiano; Alfieri, Cecilia; Roveda, Andrea; De Angelis, Gioia; Cardarelli, Luisa; Ribersani, Michela; Andreani, Marco; Lucarelli, Guido

    2014-01-01

    Allogeneic cellular gene therapy through hematopoietic stem cell transplantation is the only radical cure for congenital hemoglobinopathies like thalassemia and sickle cell anemia. Persistent mixed hematopoietic chimerism (PMC) has been described in thalassemia and sickle cell anemia. Here, we describe the clinical course of a 6-year-old girl who had received bone marrow transplant for sickle cell anemia. After the transplant, the patient showed 36% donor hematopoietic stem cells in the bone marrow, whereas in the peripheral blood there was evidence of 80% circulating donor red blood cells (RBC). The analysis of apoptosis at the Bone Marrow level suggests that Fas might contribute to the cell death of host erythroid precursors. The increase in NK cells and the regulatory T cell population observed in this patient suggests that these cells might contribute to the condition of mixed chimerism. PMID:25408852

  2. Fibrinogen and red blood cells in venous thrombosis

    PubMed Central

    Aleman, Maria M.; Walton, Bethany L.; Byrnes, James R.; Wolberg, Alisa S.

    2014-01-01

    Deep vein thrombosis and pulmonary embolism, collectively termed venous thromboembolism (VTE), affect over 1 million Americans each year. VTE is triggered by inflammation and blood stasis leading to the formation of thrombi rich in fibrin and red blood cells (RBCs). However, little is known about mechanisms regulating fibrin and RBC incorporation into venous thrombi, or how these components mediate thrombus size or resolution. Both elevated circulating fibrinogen (hyperfibrinogenemia) and abnormal fibrin(ogen) structure and function, including increased fibrin network density and resistance to fibrinolysis, have been observed in plasmas from patients with VTE. Abnormalities in RBC number and/or function have also been associated with VTE risk. RBC contributions to VTE are thought to stem from their effects on blood viscosity and margination of platelets to the vessel wall. More recent studies suggest RBCs also express phosphatidylserine, support thrombin generation, and decrease fibrinolysis. RBC interactions with fibrin(ogen) and cells, including platelets and endothelial cells, may also promote thrombus formation. The contributions of fibrin(ogen) and RBCs to the pathophysiology of VTE warrants further investigation. PMID:24759140

  3. Red Blood Cells Play a Role in Reverse Cholesterol Transport

    PubMed Central

    Hung, Kimberly T.; Berisha, Stela Z.; Ritchey, Brian M.; Santore, Jennifer; Smith, Jonathan D.

    2012-01-01

    Objective Reverse cholesterol transport (RCT) involves the removal of cholesterol from peripheral tissue for excretion in the feces. Here, we determined whether red blood cells (RBCs) can contribute to RCT. Methods and Results We performed a series of studies in apoAI-deficient mice where the HDL-mediated pathway of RCT is greatly diminished. RBCs carried a higher fraction of whole blood cholesterol than plasma in apoAI-deficient mice, and as least as much of the labeled cholesterol derived from injected foam cells appeared in RBCs compared to plasma. To determine if RBCs mediate RCT to the fecal compartment, we measured RCT in anemic and control apoAI-deficient mice and found that anemia decreased RCT to the feces by over 35% after correcting for fecal mass. Transfusion of [3H]cholesterol labeled RBCs led to robust delivery of the labeled cholesterol to the feces in apoAI-deficient hosts. In wild type mice, the majority of the blood cholesterol mass, as well as [3H]cholesterol derived from the injected foam cells, was found in plasma, and anemia did not significantly alter RCT to the feces after correction for fecal mass. Conclusion The RBC cholesterol pool is dynamic and facilitates RCT of peripheral cholesterol to the feces, particularly in the low HDL state. PMID:22499994

  4. The Effect of Pulsatile Versus Nonpulsatile Blood Flow on Viscoelasticity and Red Blood Cell Aggregation in Extracorporeal Circulation

    PubMed Central

    Ahn, Chi Bum; Kang, Yang Jun; Kim, Myoung Gon; Yang, Sung; Lim, Choon Hak; Son, Ho Sung; Kim, Ji Sung; Lee, So Young; Son, Kuk Hui; Sun, Kyung

    2016-01-01

    Background Extracorporeal circulation (ECC) can induce alterations in blood viscoelasticity and cause red blood cell (RBC) aggregation. In this study, the authors evaluated the effects of pump flow pulsatility on blood viscoelasticity and RBC aggregation. Methods Mongrel dogs were randomly assigned to two groups: a nonpulsatile pump group (n=6) or a pulsatile pump group (n=6). After ECC was started at a pump flow rate of 80 mL/kg/min, cardiac fibrillation was induced. Blood sampling was performed before and at 1, 2, and 3 hours after ECC commencement. To eliminate bias induced by hematocrit and plasma, all blood samples were adjusted to a hematocrit of 45% using baseline plasma. Blood viscoelasticity, plasma viscosity, hematocrit, arterial blood gas analysis, central venous O2 saturation, and lactate were measured. Results The blood viscosity and aggregation index decreased abruptly 1 hour after ECC and then remained low during ECC in both groups, but blood elasticity did not change during ECC. Blood viscosity, blood elasticity, plasma viscosity, and the aggregation index were not significantly different in the groups at any time. Hematocrit decreased abruptly 1 hour after ECC in both groups due to dilution by the priming solution used. Conclusion After ECC, blood viscoelasticity and RBC aggregation were not different in the pulsatile and nonpulsatile groups in the adult dog model. Furthermore, pulsatile flow did not have a more harmful effect on blood viscoelasticity or RBC aggregation than nonpulsatile flow. PMID:27298790

  5. Novel Cell Preservation Technique to Extend Bovine In Vitro White Blood Cell Viability

    PubMed Central

    Laurin, Emilie L.; McKenna, Shawn L. B.; Sanchez, Javier; Bach, Horacio; Rodriguez-Lecompte, Juan Carlos; Chaffer, Marcelo; Keefe, Greg P.

    2015-01-01

    Although cell-mediated immunity based diagnostics can be integral assays for early detection of various diseases of dairy cows, processing of blood samples for these tests is time-sensitive, often within 24 hours of collection, to maintain white blood cell viability. Therefore, to improve utility and practicality of such assays, the objective of this study was to assess the use of a novel white blood cell preservation technology in whole bovine blood. Blood samples from ten healthy cows were each divided into an unpreserved control sample and a test sample preserved with commercially-available cell transport medium. Samples were maintained at room temperature and stimulated with the mitogens pokeweed and concanavalinA, as well as with interleukin-12 p40. Stimulation was completed on days 1, 5, and 8 post-sampling. Viability of white blood cells was assessed through interferon gamma production determined with a commercial enzyme linked immunosorbent assay. In addition, mononuclear cell viability was assessed with propidium iodide flow cytometry. Greater interferon gamma production was observed on days 5 and 8 post-collection in preserved samples, with both pokeweed and concanavalinA stimulating positive interferon gamma production on day 5 post-collection. A greater proportion of the amount of interferon gamma produced on day 1 continued to be produced on days 5 and 8 post-collection with concanavalinA stimulation (with or without interleukin 12) as compared to pokeweed stimulation. Additionally, viable mononuclear cells were still present at eight days post-collection, with a higher mean proportion detected at days 5 and 8 in all stimulated preserved samples. This practical and simple method to extend in vitro white blood cell viability could benefit the efficient utilization of cell-based blood tests in ruminants. PMID:26447691

  6. What to Expect After a Blood and Marrow Stem Cell Transplant

    MedlinePlus

    ... What To Expect After a Blood and Marrow Stem Cell Transplant You’ll stay in the hospital for ... or even months after your blood and marrow stem cell transplant. Your doctors will want to be sure ...

  7. Blood cell lineage in the sea lamprey, Petromyzon marinus (Pisces: Petromyzontidae)

    USGS Publications Warehouse

    Piavis, George W.; Hiatt, James L.

    1971-01-01

    Blood cell types of the sea lamprey, Petromyzon marinus, are described and identified and the lineage of mature circulating cells in peripheral blood is traced to blast cells in the hematopoietic fat body. The fat body appears to be the phylogenetic precursor of bone marrow in higher forms, since blood cells originate and begin maturation in this tissue. Experimental animals were injected first with a hematopoietic stimulant and then (at an experimentally determined time) with pertussis vaccine to release proliferated blood cells into peripheral blood. Peripheral blood for smears was collected by cardiac exsanguination; hematopoietic tissue was extirpated for imprints; and leucocyte preparations were made by a special technique. Blood cells of the sea lamprey are apparently products of at least four distinct blast cells, each of which has a 'one end' maturation process. Results of this investigation support the polyphyletic theory of blood cell formation.

  8. Red Blood Cell Membrane-Cloaked Nanoparticles For Drug Delivery

    NASA Astrophysics Data System (ADS)

    Carpenter, Cody Westcott

    Herein we describe the development of the Red Blood Cell coated nanoparticle, RBC-NP. Purified natural erythrocyte membrane is used to coat drug-loaded poly(lacticco-glycolic acid) (PLGA). Synthetic PLGA co-polymer is biocompatible and biodegradable and has already received US FDA approval for drug-delivery and diagnostics. This work looks specifically at the retention of immunosuppressive proteins on RBC-NPs, right-sidedness of natural RBC membranes interfacing with synthetic polymer nanoparticles, sustained and retarded drug release of RBC-NPs as well as further surface modification of RBC-NPs for increased targeting of model cancer cell lines.

  9. Home improvements: malaria and the red blood cell.

    PubMed

    Foley, M; Tilley, L

    1995-11-01

    In real-estate agent's terms, the red blood cell is a renovator's dream. The mature human erythrocyte has no internal organelles, no protein synthesis machinery and no infrastructure for protein trafficking. The malaria parasite invades this empty shell and effectively converts the erythrocyte back into a fully functional eukaryotic cell. In this article, Michael Foley and Leann Tilley examine the Plasmodium falciparum proteins that interact with the membrane skeleton at different stages of the infection and speculate on the roles of these proteins in the remodelling process. PMID:15275396

  10. Donor cell leukemia after allogeneic peripheral blood stem cell transplantation: a case report and literature review.

    PubMed

    Murata, Makoto; Ishikawa, Yuichi; Ohashi, Haruhiko; Terakura, Seitaro; Ozeki, Kazutaka; Kiyoi, Hitoshi; Naoe, Tomoki

    2008-07-01

    A 49-year-old male developed recurrent acute myeloid leukemia 27 months after allogeneic peripheral blood stem cell transplantation (PBSCT) from an HLA-identical brother. The immunophenotype of the blastic cell population was incompatible with that of the pre-transplant blast cells; a mutation in C/EBPA gene was found in the pre-transplant blast cells that was not present in the post-transplant blast cells, and short tandem repeat analysis of marrow cells, which included 71% blasts, showed complete donor chimera. Thus, this recipient developed donor cell leukemia (DCL). The donor was healthy when DCL developed in the recipient as well as before donation of the peripheral blood stem cells. Only five cases of DCL after PBSCT have been reported in the literature. As a mechanism for the development of DCL, a vigorous proliferative demand on the donor cells, which often correlates with a higher likelihood of replication error or mutation, has been proposed. Peripheral blood stem cells might have an advantage in that they are associated with a low incidence of DCL development because PBSCT recipients receive a higher total cell dose than recipients of bone marrow or cord blood cells. PMID:18470599

  11. Metabolic profiling of hematopoietic stem and progenitor cells during proliferation and differentiation into red blood cells.

    PubMed

    Daud, Hasbullah; Browne, Susan; Al-Majmaie, Rasoul; Murphy, William; Al-Rubeai, Mohamed

    2016-01-25

    An understanding of the metabolic profile of cell proliferation and differentiation should support the optimization of culture conditions for hematopoietic stem and progenitor cell (HSPC) proliferation, differentiation, and maturation into red blood cells. We have evaluated the key metabolic parameters during each phase of HSPC culture for red blood cell production in serum-supplemented (SS) and serum-free (SF) conditions. A simultaneous decrease in growth rate, total protein content, cell size, and the percentage of cells in the S/G2 phase of cell cycle, as well as an increase in the percentage of cells with a CD71(-)/GpA(+) surface marker profile, indicates HSPC differentiation into red blood cells. Compared with proliferating HSPCs, differentiating HSPCs showed significantly lower glucose and glutamine consumption rates, lactate and ammonia production rates, and amino acid consumption and production rates in both SS and SF conditions. Furthermore, extracellular acidification was associated with late proliferation phase, suggesting a reduced cellular metabolic rate during the transition from proliferation to differentiation. Under both SS and SF conditions, cells demonstrated a high metabolic rate with a mixed metabolism of both glycolysis and oxidative phosphorylation (OXPHOS) in early and late proliferation, an increased dependence on OXPHOS activity during differentiation, and a shift to glycolytic metabolism only during maturation phase. These changes indicate that cell metabolism may have an important impact on the ability of HSPCs to proliferate and differentiate into red blood cells. PMID:26013297

  12. Blood cell mitochondrial DNA content and premature ovarian aging.

    PubMed

    Bonomi, Marco; Somigliana, Edgardo; Cacciatore, Chiara; Busnelli, Marta; Rossetti, Raffaella; Bonetti, Silvia; Paffoni, Alessio; Mari, Daniela; Ragni, Guido; Persani, Luca

    2012-01-01

    Primary ovarian insufficiency (POI) is a critical fertility defect characterized by an anticipated and silent impairment of the follicular reserve, but its pathogenesis is largely unexplained. The frequent maternal inheritance of POI together with a remarkable dependence of ovarian folliculogenesis upon mitochondrial biogenesis and bioenergetics suggested the possible involvement of a generalized mitochondrial defect. Here, we verified the existence of a significant correlation between blood and ovarian mitochondrial DNA (mtDNA) content in a group of women undergoing ovarian hyperstimulation (OH), and then aimed to verify whether mtDNA content was significantly altered in the blood cells of POI women. We recruited 101 women with an impaired ovarian reserve: 59 women with premature ovarian failure (POF) and 42 poor responders (PR) to OH. A Taqman copy number assay revealed a significant mtDNA depletion (P<0.001) in both POF and PR women in comparison with 43 women of similar age and intact ovarian reserve, or 53 very old women with a previous physiological menopause. No pathogenic variations in the mitochondrial DNA polymerase γ (POLG) gene were detected in 57 POF or PR women with low blood mtDNA content. In conclusion, blood cell mtDNA depletion is a frequent finding among women with premature ovarian aging, suggesting that a still undetermined but generalized mitochondrial defect may frequently predispose to POI which could then be considered a form of anticipated aging in which the ovarian defect may represent the first manifestation. The determination of mtDNA content in blood may become an useful tool for the POI risk prediction. PMID:22879975

  13. Blood Cell Mitochondrial DNA Content and Premature Ovarian Aging

    PubMed Central

    Cacciatore, Chiara; Busnelli, Marta; Rossetti, Raffaella; Bonetti, Silvia; Paffoni, Alessio; Mari, Daniela; Ragni, Guido; Persani, Luca; Arosio, M.; Beck-Peccoz, P.; Biondi, M.; Bione, S.; Bruni, V.; Brigante, C.; Cannavo`, S.; Cavallo, L.; Cisternino, M.; Colombo, I.; Corbetta, S.; Crosignani, P.G.; D'Avanzo, M.G.; Dalpra, L.; Danesino, C.; Di Battista, E.; Di Prospero, F.; Donti, E.; Einaudi, S.; Falorni, A.; Foresta, C.; Fusi, F.; Garofalo, N.; Giotti, I.; Lanzi, R.; Larizza, D.; Locatelli, N.; Loli, P.; Madaschi, S.; Maghnie, M.; Maiore, S.; Mantero, F.; Marozzi, A.; Marzotti, S.; Migone, N.; Nappi, R.; Palli, D.; Patricelli, M.G.; Pisani, C.; Prontera, P.; Petraglia, F.; Radetti, G.; Renieri, A.; Ricca, I.; Ripamonti, A.; Rossetti, R.; Russo, G.; Russo, S.; Tonacchera, M.; Toniolo, D.; Torricelli, F.; Vegetti, W.; Villa, N.; Vineis, P.; Wasniewsk, M.; Zuffardi, O.

    2012-01-01

    Primary ovarian insufficiency (POI) is a critical fertility defect characterized by an anticipated and silent impairment of the follicular reserve, but its pathogenesis is largely unexplained. The frequent maternal inheritance of POI together with a remarkable dependence of ovarian folliculogenesis upon mitochondrial biogenesis and bioenergetics suggested the possible involvement of a generalized mitochondrial defect. Here, we verified the existence of a significant correlation between blood and ovarian mitochondrial DNA (mtDNA) content in a group of women undergoing ovarian hyperstimulation (OH), and then aimed to verify whether mtDNA content was significantly altered in the blood cells of POI women. We recruited 101 women with an impaired ovarian reserve: 59 women with premature ovarian failure (POF) and 42 poor responders (PR) to OH. A Taqman copy number assay revealed a significant mtDNA depletion (P<0.001) in both POF and PR women in comparison with 43 women of similar age and intact ovarian reserve, or 53 very old women with a previous physiological menopause. No pathogenic variations in the mitochondrial DNA polymerase γ (POLG) gene were detected in 57 POF or PR women with low blood mtDNA content. In conclusion, blood cell mtDNA depletion is a frequent finding among women with premature ovarian aging, suggesting that a still undetermined but generalized mitochondrial defect may frequently predispose to POI which could then be considered a form of anticipated aging in which the ovarian defect may represent the first manifestation. The determination of mtDNA content in blood may become an useful tool for the POI risk prediction. PMID:22879975

  14. Resting blood lactate in individuals with sickle cell disease

    PubMed Central

    Petto, Jefferson; de Jesus, Jaqueline Brito; Vasques, Leila Monique Reis; Pinheiro, Renata Leão Silva; Oliveira, Aila Mascarenhas; Spinola, Kelly Aparecida Borges; Silva, Wellington dos Santos

    2011-01-01

    Background The most common hereditary hemoglobin disorder, affecting 20 million individuals worldwide, is sickle cell disease. The vascular obstruction resulting from the sickling of cells in this disease can produce local hypoxemia, pain crises and infarction in several tissues, including the bones, spleen, kidneys and lungs. Objective To determine red blood group genes in a Brazilian populations. Methods The present study is characterized as a case control study, with the aim of identifying the baseline blood lactate concentration in individuals with hemoglobin SS and SC diseases. One-way ANOVA with the Tukey post-test was used to analyze the results and a p-value < 0.05 was considered significant. Calculations were made using the INSTAT statistical program. The graphs were generated using the ORING program. The study sample was composed of 31 men and women residing in the city of Santo Antônio de Jesus, Bahia, Brazil. The individuals were divided into two groups: Group GC of 16 subjects who did not present with any type of structural hemoglobinopathy; and Group GE composed of 15 individuals with ages between 2 and 35 years old, who had the SS and SC genotypes. Sample analyses were performed with 3 mL of blood during fasting. Results The baseline blood lactate concentration of the SS and SC individuals was higher than that of the control group (p<0.001) with means of 4.86 ± 0.95; 3.30 ± 0.33; 1.31 ± 0.08 IU/L for SS, SC and controls, respectively. This corroborates the initial research hypothesis. Conclusion The baseline blood lactate of SS and SC individuals is 3 to 4 times higher than that of healthy subjects, probably due to the fact that these patients have a metabolic deviation to the anaerobic pathway. PMID:23284239

  15. Mitochondrial DNA mutations in single human blood cells.

    PubMed

    Yao, Yong-Gang; Kajigaya, Sachiko; Young, Neal S

    2015-09-01

    Determination mitochondrial DNA (mtDNA) sequences from extremely small amounts of DNA extracted from tissue of limited amounts and/or degraded samples is frequently employed in medical, forensic, and anthropologic studies. Polymerase chain reaction (PCR) amplification followed by DNA cloning is a routine method, especially to examine heteroplasmy of mtDNA mutations. In this review, we compare the mtDNA mutation patterns detected by three different sequencing strategies. Cloning and sequencing methods that are based on PCR amplification of DNA extracted from either single cells or pooled cells yield a high frequency of mutations, partly due to the artifacts introduced by PCR and/or the DNA cloning process. Direct sequencing of PCR product which has been amplified from DNA in individual cells is able to detect the low levels of mtDNA mutations present within a cell. We further summarize the findings in our recent studies that utilized this single cell method to assay mtDNA mutation patterns in different human blood cells. Our data show that many somatic mutations observed in the end-stage differentiated cells are found in hematopoietic stem cells (HSCs) and progenitors within the CD34(+) cell compartment. Accumulation of mtDNA variations in the individual CD34+ cells is affected by both aging and family genetic background. Granulocytes harbor higher numbers of mutations compared with the other cells, such as CD34(+) cells and lymphocytes. Serial assessment of mtDNA mutations in a population of single CD34(+) cells obtained from the same donor over time suggests stability of some somatic mutations. CD34(+) cell clones from a donor marked by specific mtDNA somatic mutations can be found in the recipient after transplantation. The significance of these findings is discussed in terms of the lineage tracing of HSCs, aging effect on accumulation of mtDNA mutations and the usage of mtDNA sequence in forensic identification. PMID:26149767

  16. Effects of ethanol on red blood cell rheological behavior

    PubMed Central

    Rabai, M.; Detterich, J.A.; Wenby, R.B.; Toth, K.; Meiselman, H.J.

    2016-01-01

    Consumption of red wine is associated with a decreased risk of several cardiovascular diseases (e.g., coronary artery disease, stroke), but unfortunately literature reports regarding ethanol’s effects on hemorheological parameters are not concordant. In the present study, red blood cell (RBC) deformability was tested via laser ektacytometry (LORCA, 0.3 – 30 Pa) using two approaches: 1) addition of ethanol to whole blood at 0.25% – 2% followed by incubation and testing in ethanol-free LORCA medium; 2) addition of ethanol to the LORCA medium at 0.25% – 6% then testing untreated native RBC in these media. The effects of ethanol on deformability for oxidatively stressed RBC were investigated as were changes of RBC aggregation (Myrenne Aggregometer) for cells in autologous plasma or 3% 70 kDa dextran. Significant dose-related increases of RBC deformability were observed at 0.25% (p<0.05) and higher concentrations only if ethanol was in the LORCA medium; no changes occurred for cells previously incubated with ethanol then tested in ethanol-free medium. The impaired deformability of cells pre-exposed to oxidative stress was improved only if ethanol was in the LORCA medium. RBC aggregation decreased with concentration at 0.25% and higher for cells in both autologous plasma and dextran 70. Our results indicate that ethanol reversibly improves erythrocyte deformability and irreversibly decreases erythrocyte aggregation; the relevance of these results to the health benefits of moderate wine consumption require further investigation. PMID:23089886

  17. Amplifier design considerations for blood cell counter sampling probes.

    PubMed

    Ferris, C D; Veal, B L

    1986-01-01

    Blood cell counters that operate on the Coulter principle of an electrical resistance change when a cell passes through a small sampling orifice are especially sensitive to electrical noise. The sampling probe is immersed in an electrolyte (isotonic diluent for blood cells), which in itself presents an electrochemically noisy environment. The probe, owing to its large size, acts as an antenna for environmental electrical noise up to 60 Hz. Additionally, the basic Coulter method for cell counting requires a dc potential across the sampling orifice electrodes contained within the probe. This potential produces electrolysis of the diluent and generation of gas bubbles at the electrode surfaces. Sampling (counting) time must be short (less than 30 seconds) to avoid sample heating and an intolerably high noise level as a consequence of ionic motion and gas bubble generation. The resistance change that takes place when a cell passes through the sampling orifice is only a small fraction of a percent, thus noise is a serious problem. Electric noise produces false counts and general degradation of counting function. This paper presents a discussion of a currently used method for signal acquisition and some of the problems encountered in the clinical laboratory. A novel alternative design has been implemented using integrated circuit components, which eliminates many of the problems associated with the use of small bench-type counters. Design philosophy is discussed in detail including presentation of the final circuitry developed. Performance characteristics of the signal acquisition circuitry are presented.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:3943959

  18. Deformation of red blood cells using acoustic radiation forces

    PubMed Central

    Mishra, Puja; Hill, Martyn; Glynne-Jones, Peter

    2014-01-01

    Acoustic radiation forces have been used to manipulate cells and bacteria in a number of recent microfluidic applications. The net force on a cell has been subject to careful investigation over a number of decades. We demonstrate that the radiation forces also act to deform cells. An ultrasonic standing wave field is created in a 0.1 mm glass capillary at a frequency of 7.9 MHz. Using osmotically swollen red-blood cells, we show observable deformations up to an aspect ratio of 1.35, comparable to deformations created by optical tweezing. In contrast to optical technologies, ultrasonic devices are potentially capable of deforming thousands of cells simultaneously. We create a finite element model that includes both the acoustic environment of the cell, and a model of the cell membrane subject to forces resulting from the non-linear aspects of the acoustic field. The model is found to give reasonable agreement with the experimental results, and shows that the deformation is the result of variation in an acoustic force that is directed outwards at all points on the cell membrane. We foresee applications in diagnostic devices, and in the possibility of mechanically stimulating cells to promote differentiation and physiological effects. PMID:25379070

  19. 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. PMID:26926169

  20. Improving clinical outcomes using adoptively transferred immune cells from umbilical cord blood.

    PubMed

    Hanley, Patrick J; Cruz, Conrad Russell; Shpall, Elizabeth J; Bollard, Catherine M

    2010-10-01

    Because of the necessary immunodepletion prior to cord blood transplantation as well as the immaturity of cord blood immune cells, recipients experience a high incidence of viral infection in addition to complications observed after hematopoietic stem cell transplantation, such as relapse and graft-versus-host disease. We describe current immunotherapeutic approaches to treating these complications, including the generation of antigen-specific T cells from cord blood, redirecting cord blood T cells using chimeric antigen receptors, and generating cord blood-derived natural killer cells and regulatory T cells. PMID:20818913

  1. 76 FR 11491 - Advisory Council on Blood Stem Cell Transplantation; Request for Nominations for Voting Members

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-02

    ... HUMAN SERVICES Health Resources and Services Administration Advisory Council on Blood Stem Cell... requesting nominations to fill expected vacancies on the Advisory Council on Blood Stem Cell Transplantation. The Advisory Council on Blood Stem Cell Transplantation was established pursuant to Public Law...

  2. Blood Flow through an Open-Celled Foam

    NASA Astrophysics Data System (ADS)

    Ortega, Jason; Maitland, Duncan

    2011-11-01

    The Hazen-Dupuit-Darcy (HDD) equation is commonly used in engineering applications to model the pressure gradient of flow through a porous media. One major advantage of this equation is that it simplifies the complex geometric details of the porous media into two coefficients: the permeability, K, and form factor, C. However through this simplification, the flow details within the porous media are no longer accessible, making it difficult to study the phenomena that contribute to changes in K and C due to clotting of blood flow. To obtain a more detailed understanding of blood flow through a porous media, a direct assessment of the complex interstitial geometry and flow is required. In this study, we solve the Navier-Stokes equations for Newtonian and non-Newtonian blood flow through an open-celled foam geometry obtained from a micro-CT scan. The nominal strut size of the foam sample is of O(10e-5) m and the corresponding Reynolds number based upon this length ranges up to O(10). Fitting the pressure gradient vs. Darcy velocity data with the HDD equation demonstrates that both viscous and inertial forces play an important role in the flow through the foam at these Reynolds numbers. Recirculation zones are observed to form in the wake of the pore struts, producing regions of flow characterized by both low shear rates and long fluid residence times, factors of which have been shown in previous studies to promote blood clotting.

  3. Red blood cell abnormalities and the pathogenesis of anemia in end-stage renal disease.

    PubMed

    Georgatzakou, Hara T; Antonelou, Marianna H; Papassideri, Issidora S; Kriebardis, Anastasios G

    2016-08-01

    Anemia is the most common hematologic complication in end-stage renal disease (ESRD). It is ascribed to decreased erythropoietin production, shortened red blood cell (RBC) lifespan, and inflammation. Uremic toxins severely affect RBC lifespan; however, the implicated molecular pathways are poorly understood. Moreover, current management of anemia in ESRD is controversial due to the "anemia paradox" phenomenon, which underlines the need for a more individualized approach to therapy. RBCs imprint the adverse effects of uremic, inflammatory, and oxidative stresses in a context of structural and functional deterioration that is associated with RBC removal signaling and morbidity risk. RBCs circulate in hostile plasma by raising elegant homeostatic defenses. Variability in primary defect, co-morbidity, and therapeutic approaches add complexity to the pathophysiological background of the anemic ESRD patient. Several blood components have been suggested as biomarkers of anemia-related morbidity and mortality risk in ESRD. However, a holistic view of blood cell and plasma modifications through integrated omics approaches and high-throughput studies might assist the development of new diagnostic tests and therapies that will target the underlying pathophysiologic processes of ESRD anemia. PMID:26948278

  4. In-vitro stem cell derived red blood cells for transfusion: are we there yet?

    PubMed

    Kim, Hyun Ok

    2014-03-01

    To date, the use of red blood cells (RBCs) produced from stem cells in vitro has not proved practical for routine transfusion. However, the perpetual and widespread shortage of blood products, problems related to transfusion-transmitted infections, and new emerging pathogens elicit an increasing demand for artificial blood. Worldwide efforts to achieve the goal of RBC production through stem cell research have received vast attention; however, problems with large-scale production and cost effectiveness have yet to prove practical usefulness. Some progress has been made, though, as cord blood stem cells and embryonic stem cells have shown an ability to differentiate and proliferate, and induced pluripotent stem cells have been shown to be an unlimited source for RBC production. However, transfusion of stem cell-derived RBCs still presents a number of challenges to overcome. This paper will summarize an up to date account of research and advances in stem cell-derived RBCs, delineate our laboratory protocol in producing RBCs from cord blood, and introduce the technological developments and limitations to current RBC production practices. PMID:24532496

  5. In-Vitro Stem Cell Derived Red Blood Cells for Transfusion: Are We There Yet?

    PubMed Central

    2014-01-01

    To date, the use of red blood cells (RBCs) produced from stem cells in vitro has not proved practical for routine transfusion. However, the perpetual and widespread shortage of blood products, problems related to transfusion-transmitted infections, and new emerging pathogens elicit an increasing demand for artificial blood. Worldwide efforts to achieve the goal of RBC production through stem cell research have received vast attention; however, problems with large-scale production and cost effectiveness have yet to prove practical usefulness. Some progress has been made, though, as cord blood stem cells and embryonic stem cells have shown an ability to differentiate and proliferate, and induced pluripotent stem cells have been shown to be an unlimited source for RBC production. However, transfusion of stem cell-derived RBCs still presents a number of challenges to overcome. This paper will summarize an up to date account of research and advances in stem cell-derived RBCs, delineate our laboratory protocol in producing RBCs from cord blood, and introduce the technological developments and limitations to current RBC production practices. PMID:24532496

  6. Loss of T Follicular Helper Cells In the Peripheral Blood Of Patients With Chronic Graft vs. Host Disease

    PubMed Central

    Knorr, David A.; Wang, Hongbo; Aurora, Mukta; MacMillan, Margaret L.; Holton, Shernan G.; Bergerson, Rachel; Cao, Qing; Weisdorf, Daniel J.; Cooley, Sarah; Brunstein, Claudio; Miller, Jeffery S.; Wagner, John E.; Blazar, Bruce R.; Verneris, Michael R.

    2016-01-01

    B cell anti-host antibody production plays a central role in chronic graft-vs-host disease (cGVHD). T follicular helper (TFH) cells drive B cell responses and are implicated in this process. Given differences in cGVHD incidence between umbilical cord blood (UCB) and adult donor transplant recipients, we evaluated TFH cell reconstitution kinetics to define graft source differences and their potential pathogenic role in cGVHD. Although we observed significantly fewer TFH cells in the blood of UCB recipients (vs. matched related donors (MRD)) early after transplantation, by 1 year the numbers of TFH cells were similar. Additionally, at both early (day 60) and late (1 year) time points, TFH cell phenotype was predominantly central memory cells in both cohorts. TFH cells were functional and able to produce multiple cytokines (INF-γ, TNF-α, IL-2, IL-17 and IL-21) following stimulation. In contrast to mouse models where an enhanced frequency of splenic TFH cells contributes to cGVHD, patients with cGVHD showed significantly depleted circulating TFH cells following both UCB and MRD transplantation. Low numbers of TFH cells early after UCB transplantation could directly contribute to less cGVHD in this cohort. Additionally, systemic therapy (including steroids and calcineurin inhibitors) may contribute to decreases in TFH cells in patients with cGVHD. These data provide further evidence supporting the importance of TFH cells in cGVHD pathogenesis. PMID:26806586

  7. Host-parasite interactions that guide red blood cell invasion by malaria parasites

    PubMed Central

    Paul, Aditya S.; Egan, Elizabeth S.; Duraisingh, Manoj T.

    2015-01-01

    Purpose of Review Malaria is caused by the infection and proliferation of parasites from the genus Plasmodium in red blood cells (RBCs). A free Plasmodium parasite, or merozoite, released from an infected RBC must invade another RBC host cell to sustain a blood-stage infection. Here, we review recent advances on RBC invasion by Plasmodium merozoites, focusing on specific molecular interactions between host and parasite. Recent findings Recent work highlights the central role of host-parasite interactions at virtually every stage of RBC invasion by merozoites. Biophysical experiments have for the first time measured the strength of merozoite-RBC attachment during invasion. For P. falciparum, there have been many key insights regarding the invasion ligand PfRh5 in particular, including its influence on host species tropism, a co-crystal structure with its RBC receptor basigin, and its suitability as a vaccine target. For P. vivax, researchers identified the origin and emergence of the parasite from Africa, demonstrating a natural link to the Duffy-negative RBC variant in African populations. For the simian parasite P. knowlesi, zoonotic invasion into human cells is linked to RBC age, which has implications for parasitemia during an infection and thus malaria. Summary New studies of the molecular and cellular mechanisms governing RBC invasion by Plasmodium parasites have shed light on various aspects of parasite biology and host cell tropism; and indicate opportunities for malaria control. PMID:25767956

  8. Mesenchymal precursor cells in the blood of normal individuals.

    PubMed

    Zvaifler, N J; Marinova-Mutafchieva, L; Adams, G; Edwards, C J; Moss, J; Burger, J A; Maini, R N

    2000-01-01

    STATEMENT OF FINDINGS: Mesenchymal precursor cells found in the blood (BMPCs) of normal persons adhere to plastic and glass and proliferate logarithmically in DMEM-20% fetal calf serum (FCS) without growth factors. They form cells with fibroblast-like and stromal morphology, which is not affected by eliminating CD34, CD3, or CD14 cells. Osteogenic supplements (dexamethasone, ascorbic acid, and beta-glycerophosphate) added to the culture inhibited fibroblast formation, and BMPCs assumed the cuboidal shape of osteoblasts. After 5 days in supplemented medium, the elutriated cells displayed alkaline phosphatase (AP), and the addition of bone morphogenetic protein (BMP)2 (1 ng) doubled AP production (P < 0.04). Two weeks later, 30% of the cells were very large and reacted with anti-osteocalcin antibody. The same cultures also contained sudanophlic adipocytes and multinucleated giant cells that stained for tartrate-resistant acid phosphatase (TRAP) and vitronectin receptors. Cultured BMPCs immunostain with antibodies to vimentin, type I collagen, and BMP receptors, heterodimeric structures expressed on mesenchymal lineage cells. In addition, BMPCs stain with anti-CD105 (endoglin), a putative marker for bone-marrow mesenchymal stem cells (MSCs). PMID:11056678

  9. Red blood cell aggregation and blood viscosity in an isolated heart preparation.

    PubMed

    Charansonney, O; Mouren, S; Dufaux, J; Duvelleroy, M; Vicaut, E

    1993-01-01

    We studied the effects of moderate changes in red blood cell RBC aggregation on blood flow in the vasodilated vascular bed of an isolated rat heart. We compared a non-aggregating RBC suspension (in Krebs-albumin medium) with RBC suspensions in 1% and 2% Dextran 70 (MW 70000), exhibiting two different degrees of moderate aggregation. Degrees of aggregation were precisely estimated by in vitro laser aggregometry. Each heart was perfused by the non-aggregating RBC suspension and by one aggregating RBC suspensions. Blood flow was measured in a range of perfusion pressure from 40 to 80 mm Hg. For the three RBC suspensions, linear pressure/flow relationships were found. From the comparison between the pressure/flow relationships obtained with Krebs albumin medium and either 1% or 2% Dextran, it was possible to compare in vivo the contribution of RBC to the viscosity (i.e., the relative apparent viscosity) in the 2 aggregating RBC suspensions with that of the non-aggregating RBC suspension. The contribution of RBC to the viscosity was found to be 20% to 25% lower in the 1% RBC suspension than in the non-aggregating RBC suspension. With 2% Dextran which induced a higher degree of aggregation no differences were found between the relative apparent viscosities of the aggregating and the non-aggregating suspension. From the comparison between RBC in 1% Dextran and Krebs-albumin, we concluded that in vivo a moderate RBC aggregation reduces viscous resistance due to the presence of blood in a vascular network. Since no more effect of RBC aggregation per se was found when the degree of aggregation was higher (with RBC in 2% Dextran), this suggests that, in this case, aggregation induces opposite effects along the myocardial vascular network which cancel each other out, thus inducing a nil net balance. PMID:7690613

  10. From stem cell to red blood cells in vitro: "the 12 labors of Hercules".

    PubMed

    Douay, Luc

    2010-06-01

    This article describes the research in progress that will permit the large-scale production of human red blood cells from hematopoietic stem cells. It also discusses the current state of this research, suggests the obstacles to be overcome to pass from the laboratory model to clinical practice, and analyzes the possible indications in the medium and long term. The potential interest of pluripotent stem cells as an unlimited source of red blood cells is considered. If it succeeds, this new approach could mark a considerable advance in the field of transfusion. PMID:20513558

  11. Oxidative inhibition of red blood cell ATPases by glyceraldehyde.

    PubMed

    Mira, M L; Martinho, F; Azevedo, M S; Manso, C F

    1991-11-01

    Glyceraldehyde and other simple monosaccharides autoxidize under physiological conditions, forming dicarbonyl compounds and hydrogen peroxide via intermediate free radicals. These products may have deleterious effects on cell components. In this paper we study the effect of glyceraldehyde autoxidation on red-cell ATPase activities. The autoxidation of glyceraldehyde in imidazole-glycylglycine buffer, measured by oxygen consumption, depends on the buffer concentration and decreases in the presence of superoxide dismutase and catalase. The addition of DETAPAC inhibits the autoxidation almost completely. When human red-blood-cell membranes are incubated with glyceraldehyde, the red-blood-cell ATPase activities decrease significantly. The addition of DETAPAC, GSH and DTE (dithioerythritol) protects the enzyme from inactivation, but superoxide dismutase and catalase have no effect. Methylglyoxal (a dicarbonyl which is analogous to hydroxypyruvaldehyde derived from glyceraldehyde autoxidation) proved to have a powerful inhibitory action on ATPase activities. The addition of DTE completely protects the enzyme from inactivation, suggesting that the sulphydryl groups of the active site of the enzyme are the critical targets for dicarbonyl compounds. PMID:1836354

  12. Immunoregulatory function of neonatal nucleated red blood cells in humans.

    PubMed

    Cui, Lili; Takada, Hidetoshi; Takimoto, Tomohito; Fujiyoshi, Junko; Ishimura, Masataka; Hara, Toshiro

    2016-08-01

    We found that human cord blood nucleated red blood cells (NRBCs) have a regulatory function in the innate immune reaction. These cells suppressed the production of inflammatory cytokines including TNF-α and IL-1β from monocytes in response to lipopolysaccharide (LPS). The NRBCs exerted their regulatory function even without cell-to-cell contact with the monocytes. However, IL-10 production from the monocytes by LPS stimulation in the presence of NRBCs was higher than that from LPS-stimulated monocytes cultured in the absence of NRBCs. Addition of an anti-IL-10 receptor blocking antibody restored the inflammatory cytokine production from the monocytes, suggesting that the functional change of the monocytes caused by the interaction with NRBCs was mediated by the increased IL-10 production. A whole-genome microarray analysis revealed that the monocytes expressed increased amounts of IL-10 superfamily genes after interacting with NRBCs. IL-19, which is a member of the IL-10 superfamily, enhanced IL-10 production from the monocytes, which suggested a cooperative role of the IL-10 superfamily in the suppression of inflammatory cytokine production from monocytes. Arginase, which was reported to play an important role in the suppressive function of NRBCs in mice monocytes, was found to have no significant role in human monocytes. The NRBCs seem to have a regulatory role through the induction of IL-10/IL-19 production by monocytes to suppress a vigorous innate immune reaction, which can be harmful to fetuses. PMID:27117669

  13. Metabolic pathways that correlate with post-transfusion circulation of stored murine red blood cells.

    PubMed

    de Wolski, Karen; Fu, Xiaoyoun; Dumont, Larry J; Roback, John D; Waterman, Hayley; Odem-Davis, Katherine; Howie, Heather L; Zimring, James C

    2016-05-01

    Transfusion of red blood cells is a very common inpatient procedure, with more than 1 in 70 people in the USA receiving a red blood cell transfusion annually. However, stored red blood cells are a non-uniform product, based upon donor-to-donor variation in red blood cell storage biology. While thousands of biological parameters change in red blood cells over storage, it has remained unclear which changes correlate with function of the red blood cells, as opposed to being co-incidental changes. In the current report, a murine model of red blood cell storage/transfusion is applied across 13 genetically distinct mouse strains and combined with high resolution metabolomics to identify metabolic changes that correlated with red blood cell circulation post storage. Oxidation in general, and peroxidation of lipids in particular, emerged as changes that correlated with extreme statistical significance, including generation of dicarboxylic acids and monohydroxy fatty acids. In addition, differences in anti-oxidant pathways known to regulate oxidative stress on lipid membranes were identified. Finally, metabolites were identified that differed at the time the blood was harvested, and predict how the red blood cells perform after storage, allowing the potential to screen donors at time of collection. Together, these findings map out a new landscape in understanding metabolic changes during red blood cell storage as they relate to red blood cell circulation. PMID:26921359

  14. A capillary dielectrophoretic chip for real-time blood cell separation from a drop of whole blood

    PubMed Central

    Liao, Shu-Hsien; Chang, Ching-Yu; Chang, Hsien-Chang

    2013-01-01

    This study proposes a capillary dielectrophoretic chip to separate blood cells from a drop of whole blood (approximately 1 μl) sample using negative dielectrophoretic force. The separating efficiency was evaluated by analyzing the image before and after dielectrophoretic force manipulation. Blood samples with various hematocrits (10%–60%) were tested with varied separating voltages and chip designs. In this study, a chip with 50 μm gap design achieved a separation efficiency of approximately 90% within 30 s when the hematocrit was in the range of 10%–50%. Furthermore, glucose concentration was electrochemically measured by separating electrodes following manipulation. The current response increased significantly (8.8-fold) after blood cell separation, which was attributed not only to the blood cell separation but also to sample disturbance by the dielectrophoretic force. PMID:24404015

  15. Multidrug-resistance gene (P-glycoprotein) is expressed by endothelial cells at blood-brain barrier sites

    SciTech Connect

    Cordon-Cardo, C.; O'Brien, J.P.; Casals, D.; Biedler, J.L.; Melamed, M.R.; Bertino, J.R. ); Rittman-Grauer, L. )

    1989-01-01

    Endothelial cells of human capillary blood vessels at the blood-brain and other blood-tissue barrier sites express P-glycoprotein as detected by mouse monoclonal antibodies against the human multidrug-resistance gene product. This pattern of endothelial cell expression may indicate a physiological role for P-glycoprotein in regulating the entry of certain molecules into the central nervous system and other anatomic compartments, such as the testes. These tissues, which limit the access of systemic drugs, are known pharmacologic sanctuaries for metastatic cancer. P-glycoprotein expression in capillary endothelium of brain and testes and not other tissues (i.e., kidney and placenta) may in part explain this phenomenon and could have important implications in cancer chemotherapy.

  16. Mechanical properties of stored red blood cells using optical tweezers

    NASA Astrophysics Data System (ADS)

    Fontes, Adriana; Alexandre de Thomaz, Andre; de Ysasa Pozzo, Liliana; de Lourdes Barjas-Castro, Maria; Brandao, Marcelo M.; Saad, Sara T. O.; Barbosa, Luiz Carlos; Cesar, Carlos Lenz

    2005-08-01

    We have developed a method for measuring the red blood cell (RBC) membrane overall elasticity μ by measuring the deformation of the cells when dragged at a constant velocity through a plasma fluid by an optical tweezers. The deformability of erythrocytes is a critical determinant of blood flow in the microcirculation. We tested our method and hydrodynamic models, which included the presence of two walls, by measuring the RBC deformation as a function of drag velocity and of the distance to the walls. The capability and sensitivity of this method can be evaluated by its application to a variety of studies, such as, the measurement of RBC elasticity of sickle cell anemia patients comparing homozygous (HbSS), including patients taking hydroxyrea (HU) and heterozygous (HbAS) with normal donors and the RBC elasticity measurement of gamma irradiated stored blood for transfusion to immunosupressed patients as a function of time and dose. These studies show that the technique has the sensitivity to discriminate heterozygous and homozygous sickle cell anemia patients from normal donors and even follow the course of HU treatment of Homozygous patients. The gamma irradiation studies show that there is no significant change in RBC elasticity over time for up to 14 days of storage, regardless of whether the unit was irradiated or not, but there was a huge change in the measured elasticity for the RBC units stored for more than 21 days after irradiation. These finds are important for the assessment of stored irradiated RBC viability for transfusion purposes because the present protocol consider 28 storage days after irradiation as the limit for the RBC usage.

  17. Quantitative phosphoproteome analysis of embryonic stem cell differentiation toward blood

    PubMed Central

    Piazzi, Manuela; Williamson, Andrew; Lee, Chia-Fang; Pearson, Stella; Lacaud, Georges; Kouskoff, Valerie; McCubrey, James A.; Cocco, Lucio; Whetton, Anthony D.

    2015-01-01

    Murine embryonic stem (ES) cells can differentiate in vitro into three germ layers (endodermic, mesodermic, ectodermic). Studies on the differentiation of these cells to specific early differentiation stages has been aided by an ES cell line carrying the Green Fluorescent Protein (GFP) targeted to the Brachyury (Bry) locus which marks mesoderm commitment. Furthermore, expression of the Vascular Endothelial Growth Factor receptor 2 (Flk1) along with Bry defines hemangioblast commitment. Isobaric-tag for relative and absolute quantification (iTRAQTM) and phosphopeptide enrichment coupled to liquid chromatography separation and mass spectrometry allow the study of phosphorylation changes occurring at different stages of ES cell development using Bry and Flk1 expression respectively. We identified and relatively quantified 37 phosphoentities which are modulated during mesoderm-induced ES cells differentiation, comparing epiblast-like, early mesoderm and hemangioblast-enriched cells. Among the proteins differentially phosphorylated toward mesoderm differentiation were: the epigenetic regulator Dnmt3b, the protein kinase GSK3b, the chromatin remodeling factor Smarcc1, the transcription factor Utf1; as well as protein specifically related to stem cell differentiation, as Eomes, Hmga2, Ints1 and Rif1. As most key factors regulating early hematopoietic development have also been implicated in various types of leukemia, understanding the post-translational modifications driving their regulation during normal development could result in a better comprehension of their roles during abnormal hematopoiesis in leukemia. PMID:25890499

  18. SEM analysis of red blood cells in aged human bloodstains.

    PubMed

    Hortolà, P

    1992-08-01

    Mammal red blood cells (RBC) in bloodstains have been previously detected by light microscopy on stone tools from as early as 100,000 +/- 25,000 years ago. In order to evaluate the degree of morphological preservation of erythrocytes in bloodstains, an accidental human blood smear on white chert and several experimental bloodstains on hard substrates (the same stone-white chert; another type of stone-graywacke; a non-stone support-stainless steel), were stored in a room, in non-sterile and fluctuating conditions, for lengths of time ranging from 3 to 18 months. Afterwards, the specimens were coated with gold and examined by a Cambridge Stereoscan 120 scanning electron microscope. Results revealed a high preservation of RBC integrity, with the maintenance of several discocytary shapes, a low tendency to echinocytosis and a frequent appearance of a moon-like erythrocytary shape in the thinner areas of the bloodstains. PMID:1398371

  19. Effects of pegylated hamster red blood cells on microcirculation.

    PubMed

    Chen, Peter C Y; Huang, Wei; Stassinopoulos, Adonis; Cheung, Anthony T W

    2008-01-01

    The objective of this study was to examine the effects of polyethylene glycol (PEG) treated red blood cells (RBCs) on the microcirculation in a hamster back skin window chamber model. Donor hamster RBCs were PEGylated through an incubation with an activated PEG solution, washed, resuspended, and infused through a 10% volume top loading procedure into the carotid artery in an awake Syrian Golden hamster. Eight hamster groups were treated with activated PEG different sizes and concentrations: 0.05 mM-5 kDa PEG, 0.5 mM-5 kDa PEG, 1.1 mM-5 kDa PEG, 2.2 mM-5 kDa PEG, 22 mM-5 kDa PEG, 0.05 mM-20 kDa PEG, 0.5 mM-20 kDa PEG, and 5 mM-20 kDa PEG. Non-treated RBCs were used as control. The microvascular bed under observation was videotaped 30 min before the infusion and followed for 30 min post infusion. The diameter of individual blood vessels and blood flow velocities in selected vessels was measured. Hematocrit and hemoglobin concentration were recorded before infusion and at the end of experiment. Tissue pO(2) was also monitored. Results showed the hamsters tolerated the PEGylated RBCs without apparent ill effects. No significant changes were recorded for the hematocrit, the hemoglobin concentration, the blood vessel diameters, blood flow velocities, and the interstitial partial oxygen pressure (pO(2)) before, during, and after the injections of PEG-RBCs (P > 0.05). Unlike most hemoglobin-based oxygen carrying compounds, which can cause vasoconstriction, the PEGylated RBCs did not produce any measurable vasoactivity. Together with the absence of rouleaux formation and the fact that PEG molecules can mask the surface antigens on RBCs, PEGylation appeared promising as a circulation enhancement treatment. PMID:18649167

  20. Procoagulant activity in stored units of red blood cells.

    PubMed

    Aleshnick, Maya; Foley, Jonathan H; Keating, Friederike K; Butenas, Saulius

    2016-06-10

    The procoagulant activity (PA) of stored units of red blood cells (RBC) increases over time, which is related to the expression/exposure of tissue factor (TF). However, there is a discrepancy between the TF measured and changes in PA observed, suggesting that other blood components contribute to this activity. Our goal was to evaluate changes in PA of stored RBCs and to determine possible contributors to it. RBC units from 4 healthy donors were prepared and stored at 4 °C. On selected days, RBC aliquots were reconstituted with autologous plasma and tested in the thromboelastography assay. Corresponding supernatants were tested in a clotting assay. For all donors, the clotting time (CT) of reconstituted RBC units decreased from ∼3000-4000s on day 1 to ∼1000-1600s on day 30, with the most dramatic changes occurring between days 1 and 5. Anti-TF antibody slightly prolonged the CT. The concentration of TF did not change significantly over time and was within the range of 0.3-2.3 pM. Bovine lactadherin (LTD) prolonged the CT of the RBC (by 2.4-3.4-fold in days 3-5 and by 1.3-1.8-fold at day 30). Anti-TF antibody together with LTD had a cumulative effect on the CT prolongation. CT of supernatants responded to both anti-TF and anti-FXIa antibodies. Three contributors to the PA of stored RBC were identified, i.e. FXIa in solution and phosphatidylserine and TF exposed on blood cells and microparticles. Failure of LTD and antibodies to completely eliminate PA suggests that other components of blood could contribute to it. PMID:27150627

  1. Smooth muscle progenitor cells from peripheral blood promote the neovascularization of endothelial colony-forming cells

    SciTech Connect

    Joo, Hyung Joon; Seo, Ha-Rim; Jeong, Hyo Eun; Choi, Seung-Cheol; Park, Jae Hyung; Yu, Cheol Woong; Hong, Soon Jun; Chung, Seok; Lim, Do-Sun

    2014-07-11

    Highlights: • Two distinct vascular progenitor cells are induced from adult peripheral blood. • ECFCs induce vascular structures in vitro and in vivo. • SMPCs augment the in vitro and in vivo angiogenic potential of ECFCs. • Both cell types have synergistic therapeutic potential in ischemic hindlimb model. - Abstract: Proangiogenic cell therapy using autologous progenitors is a promising strategy for treating ischemic disease. Considering that neovascularization is a harmonized cellular process that involves both endothelial cells and vascular smooth muscle cells, peripheral blood-originating endothelial colony-forming cells (ECFCs) and smooth muscle progenitor cells (SMPCs), which are similar to mature endothelial cells and vascular smooth muscle cells, could be attractive cellular candidates to achieve therapeutic neovascularization. We successfully induced populations of two different vascular progenitor cells (ECFCs and SMPCs) from adult peripheral blood. Both progenitor cell types expressed endothelial-specific or smooth muscle-specific genes and markers, respectively. In a protein array focused on angiogenic cytokines, SMPCs demonstrated significantly higher expression of bFGF, EGF, TIMP2, ENA78, and TIMP1 compared to ECFCs. Conditioned medium from SMPCs and co-culture with SMPCs revealed that SMPCs promoted cell proliferation, migration, and the in vitro angiogenesis of ECFCs. Finally, co-transplantation of ECFCs and SMPCs induced robust in vivo neovascularization, as well as improved blood perfusion and tissue repair, in a mouse ischemic hindlimb model. Taken together, we have provided the first evidence of a cell therapy strategy for therapeutic neovascularization using two different types of autologous progenitors (ECFCs and SMPCs) derived from adult peripheral blood.

  2. Theory of the sphering of red blood cells.

    PubMed

    Fung, Y C; Tong, P

    1968-02-01

    A rigorous mathematical solution of the sphering of a red blood cell is obtained under the assumptions that the red cells is a fluid-filled shell and that it can swell into a perfect sphere in an appropriate hypotonic medium. The solution is valid for finite strain of the cell membrane provided that the membrane is isotropic, elastic and incompressible. The most general nonlinear elastic stress-strain law for the membrane in a state of generalized plane stress is used. A necessary condition for a red cell to be able to sphere is that its extensional stiffness follow a specific distribution over the membrane. This distribution is strongly influenced by the surface tension in the cell membrane. A unique relation exists between the extensional stiffness, pressure differential, surface tension, and the ratio of the radius of the sphere to that of the undeformed red cell. The functional dependence of this stiffness distribution on various physical parameters is presented. A critique of some current literature on red cell mechanics is presented. PMID:5639934

  3. Measurement of red blood cell mechanics during morphological changes

    NASA Astrophysics Data System (ADS)

    Popescu, Gabriel; Park, Yongkeun; Best, Catherine; Dasari, Ramachandra; Feld, Michael; Kuriabova, Tatiana; Henle, Mark; Levine, Alex

    2010-03-01

    The human red blood cell (RBC) membrane, a fluid lipid bilayer tethered to an elastic 2D spectrin network, provides the principal control of the cell's morphology and mechanics. These properties, in turn, influence the ability of RBCs to transport oxygen in circulation. Current mechanical measurements of RBCs rely on external loads. Here we apply a Noncontact optical interferometric technique to quantify the thermal fluctuations of RBC membranes with 3 nm accuracy over a broad range of spatial and temporal frequencies. Combining this technique with a new mathematical model describing RBC membrane undulations, we measure the mechanical changes of RBCs as they undergo a transition from the normal discoid shape to the abnormal echinocyte and spherical shapes. These measurements indicate that, coincident with this morphological transition, there is a significant increase in the membrane's shear and bending moduli. This mechanical transition can alter cell circulation and impede oxygen delivery.

  4. Method using CO for extending the useful shelf-life of refrigerated red blood cells

    DOEpatents

    Bitensky, Mark W.

    1995-01-01

    Method using CO for extending the useful shelf-life of refrigerated red blood cells. Carbon monoxide is utilized for stabilizing hemoglobin in red blood cells to be stored at low temperature. Changes observed in the stored cells are similar to those found in normal red cell aging in the body, the extent thereof being directly related to the duration of refrigerated storage. Changes in cell buoyant density, vesiculation, and the tendency of stored cells to bind autologous IgG antibody directed against polymerized band 3 IgG, all of which are related to red blood cell senescence and increase with refrigerated storage time, have been substantially slowed when red blood cells are treated with CO. Removal of the carbon monoxide from the red blood cells is readily and efficiently accomplished by photolysis in the presence of oxygen so that the stored red blood cells may be safely transfused into a recipient.

  5. Method using CO for extending the useful shelf-life of refrigerated red blood cells

    DOEpatents

    Bitensky, M.W.

    1995-12-19

    A method is disclosed using CO for extending the useful shelf-life of refrigerated red blood cells. Carbon monoxide is utilized for stabilizing hemoglobin in red blood cells to be stored at low temperature. Changes observed in the stored cells are similar to those found in normal red cell aging in the body, the extent thereof being directly related to the duration of refrigerated storage. Changes in cell buoyant density, vesiculation, and the tendency of stored cells to bind autologous IgG antibody directed against polymerized band 3 IgG, all of which are related to red blood cell senescence and increase with refrigerated storage time, have been substantially slowed when red blood cells are treated with CO. Removal of the carbon monoxide from the red blood cells is readily and efficiently accomplished by photolysis in the presence of oxygen so that the stored red blood cells may be safely transfused into a recipient. 5 figs.

  6. Mach-Zehnder interferometer for separation of platelets from red blood cells using dielectrophoretics

    NASA Astrophysics Data System (ADS)

    Shwetha, M.; Narayan, K.

    2016-03-01

    In this work, separation of platelets from red blood cells using Mach-Zehnder interferometer is shown using Dielectrophoretics (DEP). The proposed model demonstrates continuous separation of platelets from red blood cells. Mach-Zehnder Interferometer (MZI) has two arms, in which sensing arm will sense according to the applied voltage and separate the platelets from mixed blood cells. The platelets and the red blood cells will flow in two outlets of MZI. Microfluidic device is used to separate the RBC's and the platelets from the mixed blood cells.

  7. Cord blood stem cells revert glioma stem cell EMT by down regulating transcriptional activation of Sox2 and Twist1

    PubMed Central

    Velpula, Kiran Kumar; Dasari, Venkata Ramesh; Tsung, Andrew J.; Dinh, Dzung H.; Rao, Jasti S.

    2011-01-01

    The dynamic nature of cancer stem cells that underlie metastasis or their ability to switch between different cellular identities, as in EMT and MET, has profound implications for cancer therapy. The functional relationship between molecules involved in cancer cell stemness and metastasis is not clear. In this regard, our studies on hGBM tissue grade IV specimens showed significant expression of Twist1 and Sox2, known mesenchymal and stemness related markers, respectively, indicating their association with glial tumor genesis and metastasis. The glioma stem cells obtained from CD133+ cells demonstrated increased expression of Twist1 and Sox2 accompanied by significant increase in the mesenchymal markers such as N-cadherin, vimentin and β-catenin. Our studies on glioma stem cells treatment with human umbilical cord blood derived- mesenchymal stem cells, showed down regulation of Twist1 and Sox2 proteins, apart from other mesenchymal stem cell markers. Based on the in vitro experiments and in vivo intracranial xenograft mouse model studies, we elucidated the potential therapeutic role of hUCBSC in suppressing glioma cancer stemness by the induction of MET. PMID:22184289

  8. Cord blood stem cells revert glioma stem cell EMT by down regulating transcriptional activation of Sox2 and Twist1.

    PubMed

    Velpula, Kiran Kumar; Dasari, Venkata Ramesh; Tsung, Andrew J; Dinh, Dzung H; Rao, Jasti S

    2011-12-01

    The dynamic nature of cancer stem cells that underlie metastasis or their ability to switch between different cellular identities, as in EMT and MET, has profound implications for cancer therapy. The functional relationship between molecules involved in cancer cell stemness and metastasis is not clear. In this regard, our studies on hGBM tissue grade IV specimens showed significant expression of Twist1 and Sox2, known mesenchymal and stemness related markers, respectively, indicating their association with glial tumor genesis and metastasis. The glioma stem cells obtained from CD133+ cells demonstrated increased expression of Twist1 and Sox2 accompanied by significant increase in the mesenchymal markers such as N-cadherin, vimentin and β-catenin. Our studies on glioma stem cells treatment with human umbilical cord blood derived- mesenchymal stem cells, showed down regulation of Twist1 and Sox2 proteins, apart from other mesenchymal stem cell markers. Based on the in vitro experiments and in vivo intracranial xenograft mouse model studies, we elucidated the potential therapeutic role of hUCBSC in suppressing glioma cancer stemness by the induction of MET. PMID:22184289

  9. Measuring skewness of red blood cell deformability distribution by laser ektacytometry

    SciTech Connect

    Nikitin, S Yu; Priezzhev, A V; Lugovtsov, A E; Ustinov, V D

    2014-08-31

    An algorithm is proposed for measuring the parameters of red blood cell deformability distribution based on laser diffractometry of red blood cells in shear flow (ektacytometry). The algorithm is tested on specially prepared samples of rat blood. In these experiments we succeeded in measuring the mean deformability, deformability variance and skewness of red blood cell deformability distribution with errors of 10%, 15% and 35%, respectively. (laser biophotonics)

  10. Transport of diseased red blood cells in the spleen

    NASA Astrophysics Data System (ADS)

    Peng, Zhangli; Pivkin, Igor; Dao, Ming

    2012-11-01

    A major function of the spleen is to remove old and diseased red blood cells (RBCs) with abnormal mechanical properties. We investigated this mechanical filtering mechanism by combining experiments and computational modeling, especially for red blood cells in malaria and sickle cell disease (SCD). First, utilizing a transgenic line for 3D confocal live imaging, in vitro capillary assays and 3D finite element modeling, we extracted the mechanical properties of both the RBC membrane and malaria parasites for different asexual malaria stages. Secondly, using a non-invasive laser interferometric technique, we optically measured the dynamic membrane fluctuations of SCD RBCs. By simulating the membrane fluctuation experiment using the dissipative particle dynamics (DPD) model, we retrieved mechanical properties of SCD RBCs with different shapes. Finally, based on the mechanical properties obtained from these experiments, we simulated the full fluid-structure interaction problem of diseased RBCs passing through endothelial slits in the spleen under different fluid pressure gradients using the DPD model. The effects of the mechanical properties of the lipid bilayer, the cytoskeleton and the parasite on the critical pressure of splenic passage of RBCs were investigated separately. This work is supported by NIH and Singapore-MIT Alliance for Science and Technology (SMART).

  11. Manipulation of red blood cells with electric field

    NASA Astrophysics Data System (ADS)

    Saboonchi, Hossain; Esmaeeli, Asghar

    2009-11-01

    Manipulation of bioparticles and macromolecules is the central task in many biological and biotechnological processes. The current methods for physical manipulation takes advantage of different forces such as acoustic, centrifugal, magnetic, electromagnetic, and electric forces, as well as using optical tweezers or filtration. Among all these methods, however, the electrical forces are particularly attractive because of their favorable scale up with the system size which makes them well-suited for miniaturization. Currently the electric field is used for transportation, poration, fusion, rotation, and separation of biological cells. The aim of the current research is to gain fundamental understanding of the effect of electric field on the human red blood cells (RBCs) using direct numerical simulation. A front tracking/finite difference technique is used to solve the fluid flow and electric field equations, where the fluid in the cell and the blood (plasma) is modeled as Newtonian and incompressible, and the interface separating the two is treated as an elastic membrane. The behavior of RBCs is investigated as a function of the controlling parameters of the problem such as the strength of the electric field.

  12. Vibrational modes of hemoglobin in red blood cells.

    PubMed Central

    Martel, P; Calmettes, P; Hennion, B

    1991-01-01

    Equine red blood cells were washed in saline heavy water (2H2O) to exchange the hydrogen atoms of the non-hemoglobin components with deuterons. This led to novel neutron scattering measurements of protein vibrations within a cellular system and permitted a comparison with inelastic neutron scattering measurements on purified horse hemoglobin, either dry or wetted with 2H2O. As a function of wavevector transfer Q and the frequency transfer v the neutron response typified by the dynamic structure factor S(Q, v) was found to be similar for extracted and cellular hemoglobin at low and high temperatures. At 77 K, in the cells, a peak in S(Q, v) due to the protein was found near 0.7 THz, approximately half the frequency of a strong peak in the aqueous medium. Measurements at higher temperatures (170 and 230 K) indicated similar small shifts downwards in the peak frequencies of both components. At 260 K the low frequency component became predominantly quasielastic, but a significant inelastic component could still be ascribed to the aqueous scattering. Near 295 K the frequency responses of both components were similar and centered near zero. When scattering due to water is taken into account it appears that the protein neutron response in, or out of, red blood cells is little affected by hydration in the low frequency regime where Van der Waals forces are thought to be effective. PMID:1849028

  13. Gossypol effects on endothelial cells and tumor blood flow

    SciTech Connect

    Benz, C.C.; Iyer, S.B.; Asgari, H.S.; Matlin, S.A.; Aronson, F.R. ); Barchowsky, A. )

    1991-01-01

    Isomers (-,+) of the antitumor agent gossypol (G) were studied for their ability to reduce tumor ATP and blood flow in rats bearing subcutaneously implanted pancreatic tumors. A 50% reduction in tumor ATP/Pi within 1h of a single injection of -G was associated with a 60% decline in tumor blood flow. To determine if these changes in tumor physiology could be due to a direct drug effect on tumor endothelium, G isomers were compared for their ability to alter protein ({sup 125}1-BSA) permeability and metabolic ({sup 32}P) labelling of cultured endothelial cells. Treatments for 1h produced no endothelial cell leakage, but 24h exposures to either -G or +G produced complete permeability of the monolayers to {sup 125}1-BSA. In contrast, 0.5-1.0h exposures to -G or +G produced 2 to 3-fold increases in phosphorylated 27kDa heat-shock protein, hsp-27. Hsp-27 phosphoprotein isoforms were differentially labelled following -G and +G exposures with the phosphorylation profile of -G appearing most similar to that of oxyradical producing agents known to induce hsp-27 and injure endothelial cells. The authors postulate that the tumor ischemic effects of -G are mediated by endothelial response to oxyradical production in a mechanism similar to that of tissue ischemia-reperfusion injury.

  14. Red blood cell as an adaptive optofluidic microlens

    NASA Astrophysics Data System (ADS)

    Miccio, L.; Memmolo, P.; Merola, F.; Netti, P. A.; Ferraro, P.

    2015-03-01

    The perspective of using live cells as lenses could open new revolutionary and intriguing scenarios in the future of biophotonics and biomedical sciences for endoscopic vision, local laser treatments via optical fibres and diagnostics. Here we show that a suspended red blood cell (RBC) behaves as an adaptive liquid-lens at microscale, thus demonstrating its imaging capability and tunable focal length. In fact, thanks to the intrinsic elastic properties, the RBC can swell up from disk volume of 90 fl up to a sphere reaching 150 fl, varying focal length from negative to positive values. These live optofluidic lenses can be fully controlled by triggering the liquid buffer’s chemistry. Real-time accurate measurement of tunable focus capability of RBCs is reported through dynamic wavefront characterization, showing agreement with numerical modelling. Moreover, in analogy to adaptive optics testing, blood diagnosis is demonstrated by screening abnormal cells through focal-spot analysis applied to an RBC ensemble as a microlens array.

  15. Effects of Malaria Parasite Density on Blood Cell Parameters

    PubMed Central

    Kotepui, Manas; Piwkham, Duangjai; PhunPhuech, Bhukdee; Phiwklam, Nuoil; Chupeerach, Chaowanee; Duangmano, Suwit

    2015-01-01

    Changes in blood cell parameters are already a well-known feature of malarial infections. To add to this information, the objective of this study was to investigate the varying effects that different levels of parasite density have on blood cell parameters. Patients diagnosed with malaria at Phobphra Hospital, Tak Province, Thailand between January 1st 2009 and January 1st 2012 were recruited as subjects for data collection. Blood cell parameters of 2,024 malaria-infected patients were evaluated and statistically analyzed. Neutrophil and platelet counts were significantly higher, however, RBC count was significantly lower in patients with P. falciparum infection compared to those with P. vivax infection (p<0.0001). Leukocyte counts were also significantly higher in patients with high parasitemia compared to those with low and moderate parasitemia. In terms of differential leukocyte count, neutrophil count was significantly higher in patients with high parasitemia compared to those with low and moderate parasitemia (p<0.0001). On the other hand, both lymphocyte and monocyte counts were significantly lower in patients with high parasitemia (p<0.0001). RBC count and Hb concentration, as well as platelet count were also significantly reduced (p<0.05) and (p<0.0001), respectively. To summarize, patients infected with different malaria parasites exhibited important distinctive hematological parameters, with neutrophil and eosinophil counts being the two hematological parameters most affected. In addition, patients infected with different malarial densities also exhibited important changes in leukocyte count, platelet count and hemoglobin concentration during the infection. These findings offer the opportunity to recognize and diagnose malaria related anemia, help support the treatment thereof, as well as relieve symptoms of severe malaria in endemic regions. PMID:25807235

  16. Dynamics of model blood cells in shear flow

    NASA Astrophysics Data System (ADS)

    Podgorski, Thomas; Callens, Natacha; Minetti, Christophe; Coupier, Gwennou; Dubois, Frank; Misbah, Chaouqi

    The dynamics of a vesicle suspension in shear flow was investigated by digital holographic microscopy [1] in parabolic flights and in the MASER 11 sounding rocket. Vesicles are lipid membranes which mimic the mechanical behaviour of cells, such as red blood cells in flow. In a simple shear flow between parallel walls, a lift force of purely viscous origin pushes vesicles away from walls. Our parabolic flight experiments [2] reveal that the lift velocity in a dilute suspen-sion is well described by theoretical predictions by Olla. As vesicles gather near the center of the flow chamber due to lift forces from both walls, one expects hydrodynamic interactions of pairs of vesicles to result in shear induced diffusion in the suspension. The BIOMICS experi-ment in the MASER 11 sounding rocket revealed a complex spatial structure of a polydisperse vesicle suspension due to the interplay between lift forces from the walls and hydrodynamic interactions. These phenomena have a strong impact on the structure and rheology of blood in small vessels, and a precise knowledge of the dynamics of migration and diffusion of soft particles in flow can lead to alternative ways to separate and sort blood cells. 1. Dubois, F., Schockaert, C., Callens, N., Yourrassowsky, C., "Focus plane detection criteria in digital holography microscopy by amplitude analysis", Opt. Express, Vol. 14, pp 5895-5908, 2006 2. Callens, N., Minetti, C., Coupier, G., Mader, M.-A., Dubois, F., Misbah, C., Podgorski, T., "Hydrodynamics lift of vesicles under shear flow in microgravity", Europhys. Lett., Vol. 83, p. 24002, 2008

  17. Deoxygenation Reduces Sickle Cell Blood Flow at Arterial Oxygen Tension.

    PubMed

    Lu, Xinran; Wood, David K; Higgins, John M

    2016-06-21

    The majority of morbidity and mortality in sickle cell disease is caused by vaso-occlusion: circulatory obstruction leading to tissue ischemia and infarction. The consequences of vaso-occlusion are seen clinically throughout the vascular tree, from the relatively high-oxygen and high-velocity cerebral arteries to the relatively low-oxygen and low-velocity postcapillary venules. Prevailing models of vaso-occlusion propose mechanisms that are relevant only to regions of low oxygen and low velocity, leaving a wide gap in our understanding of the most important pathologic process in sickle cell disease. Progress toward understanding vaso-occlusion is further challenged by the complexity of the multiple processes thought to be involved, including, but not limited to 1) deoxygenation-dependent hemoglobin polymerization leading to impaired rheology, 2) endothelial and leukocyte activation, and 3) altered cellular adhesion. Here, we chose to focus exclusively on deoxygenation-dependent rheologic processes in an effort to quantify their contribution independent of the other processes that are likely involved in vivo. We take advantage of an experimental system that, to our knowledge, uniquely enables the study of pressure-driven blood flow in physiologic-sized tubes at physiologic hematocrit under controlled oxygenation conditions, while excluding the effects of endothelium, leukocyte activation, adhesion, inflammation, and coagulation. We find that deoxygenation-dependent rheologic processes are sufficient to increase apparent viscosity significantly, slowing blood flow velocity at arterial oxygen tension even without additional contributions from inflammation, adhesion, and endothelial and leukocyte activation. We quantify the changes in apparent viscosity and define a set of functional regimes of sickle cell blood flow personalized for each patient that may be important in further dissecting mechanisms of in vivo vaso-occlusion as well as in assessing risk of patient

  18. Changes in En(a-) human red blood cell membranes during in vivo ageing.

    PubMed

    Shinozuka, T; Miyata, Y; Takei, S; Yoshida, R; Ogamo, A; Nakagawa, Y; Kuroda, N; Yanagida, J

    1996-01-01

    The human red blood cells with phenotype En(a-) were characterized by the lack of MN antigens. The red blood cells with phenotype En(a-) which were found in a Japanese family were tested to clarify the changes in membrane surfaces of the red blood cells during in vivo ageing. The contents of sialic acid, glucose, mannose, galactose, fucose, N-acetylglucosamine and N-acetylgalactosamine of the red blood cell membranes obtained from the old red blood cells with phenotype En(a-) were significantly lower than those of the young red blood cell membranes. Neither the young nor the old red blood cells with phenotype En(a-) showed the agglutination with Arachis hypogaea (PNA) which was capable of binding to T agglutinogen. It is presumed that En(a-) red blood cells are not exposed to sialidase in vivo. In comparison with the young En(a-) red blood cell membranes, the number and the distribution density of lectin receptor sites on the old ones for Limulus polyphemus (LPA), Canavalia ensiformis (Con A), Triticum vulgaris (WGA) and Bauhinia purpurea (BPA) were significantly lower. It is thought that En(a-) red blood cell ageing is accompanied by elimination of some sialoglycoconjugates which have affinity for LPA, Con A, WGA and BPA, whereas En(a-) red blood cells lack glycophorin A. PMID:8866734

  19. Biological effects of the electrostatic field: red blood cell-related alterations of oxidative processes in blood

    NASA Astrophysics Data System (ADS)

    Harutyunyan, Hayk A.; Sahakyan, Gohar V.

    2016-01-01

    The aim of this study was to determine activities of pro-/antioxidant enzymes, reactive oxygen species (ROS) content, and oxidative modification of proteins and lipids in red blood cells (RBCs) and blood plasma of rats exposed to electrostatic field (200 kV/m) during the short (1 h) and the long periods (6 day, 6 h daily). Short-term exposure was characterized by the increase of oxidatively damaged proteins in blood of rats. This was strongly expressed in RBC membranes. After long-term action, RBC content in peripheral blood was higher than in control ( P < 0.01) and the attenuation of prooxidant processes was shown.

  20. Design of an automated algorithm for labeling cardiac blood pool in gated SPECT images of radiolabeled red blood cells

    SciTech Connect

    Hebert, T.J. |; Moore, W.H.; Dhekne, R.D.; Ford, P.V.; Wendt, J.A.; Murphy, P.H.; Ting, Y.

    1996-08-01

    The design of an automated computer algorithm for labeling the cardiac blood pool within gated 3-D reconstructions of the radiolabeled red blood cells is investigated. Due to patient functional abnormalities, limited resolution, and noise, certain spatial and temporal features of the cardiac blood pool that one would anticipate finding in every study are not present in certain frames or with certain patients. The labeling of the cardiac blood pool requires an algorithm that only relies upon features present in all patients. The authors investigate the design of a fully-automated region growing algorithm for this purpose.

  1. Immunoglobulin-secreting cells in cord blood: effects of Epstein-Barr virus and interleukin-4.

    PubMed

    Gudmundsson, K O; Thorsteinsson, L; Gudmundsson, S; Haraldsson, A

    1999-07-01

    The contribution of cord blood B lymphocytes to the immune response has been under considerable investigation. Cord blood B cells produce almost no antibodies except of the immunoglobulin (Ig)M isotype, indicating immaturity of the cells or the environment they reside in. The aim of this study was to investigate the number of circulating IgA-, IgM-, IgG-, and IgE-producing cells in cord blood in comparison to adult peripheral blood using the ELISPOT method. Moreover, we studied the effect of transformation with the Epstein-Barr virus (EBV) on the proportion of cells producing different isotypes with or without interleukin (IL)-4. Cord blood had IgM-producing cells circulating predominantly, but also some IgA- and IgG-producing cells, whereas adult peripheral blood contained high amounts of circulating IgA-producing cells and some IgM- and IgG-producing cells. No circulating IgE-producing cells were found in either group. Transformation by EBV caused significant expansion of IgA-, IgM-, and IgG-producing cells in adult peripheral blood, but almost only of IgM-producing cells in cord blood. A low but detectable expansion of IgA- and IgG-producing cells was found. Cells producing IgE were still not found, even after EBV transformation. However, EBV transformation in the presence of IL-4 increased the numbers of IgE-producing cells significantly both in cord blood and adult peripheral blood. These findings indicate that cord blood contains some circulating IgA- and IgG-producing cells that are expanded to some extent after EBV infection. They also indicate that cord blood B cells have a similar capacity for IgE production to adult peripheral blood B cells when appropriately stimulated. PMID:10404047

  2. The nature of multiphoton fluorescence from red blood cells

    NASA Astrophysics Data System (ADS)

    Saytashev, Ilyas; Murphy, Michael; Osseiran, Sam; Spence, Dana M.; Evans, Conor L.; Dantus, Marcos

    2016-03-01

    We report on the nature of multiphoton excited fluorescence observed from human erythrocytes (red blood cells RBC's) and their "ghosts" following 800nm sub-15 fs excitation. The detected optical signal is assigned as two-photon excited fluorescence from hemoglobin. Our findings are supported by wavelength-resolved fluorescence lifetime decay measurements using time-correlated single photon counting system from RBC's, their ghosts as well as in vitro samples of various fluorophores including riboflavin, NADH, NAD(P)H, hemoglobin. We find that low-energy and short-duration pulses allow two-photon imaging of RBC's, but longer more intense pulses lead to their destruction.

  3. Cytoskeleton confinement of red blood cell membrane fluctuations

    NASA Astrophysics Data System (ADS)

    Gov, Nir; Zilman, Anton; Safran, Samuel

    2003-03-01

    We analyze theoretically both the static and dynamic fluctuation spectrum of the red-blood cell in a unified manner, using a simple model of the composite membrane. In this model, the two-dimensional spectrin network that forms the cytoskeleton is treated as a rigid shell, located at a fixed, average distance from the lipid bilayer. The cytoskeleton thereby confines both the static and dynamic fluctuations of the lipid bilayer. The predictions of the model account for the wavevector and frequency dependence of the experimental data.

  4. Cytoskeleton Confinement and Tension of Red Blood Cell Membranes

    NASA Astrophysics Data System (ADS)

    Gov, N.; Zilman, A. G.; Safran, S.

    2003-06-01

    We analyze theoretically both the static and dynamic fluctuation spectra of the red blood cell in a unified manner, using a simple model of the composite membrane. In this model, the two-dimensional spectrin network that forms the cytoskeleton is treated as a rigid shell, located at a fixed, average distance from the lipid bilayer. The cytoskeleton thereby confines both the static and dynamic fluctuations of the lipid bilayer. The sparse connections of the cytoskeleton and bilayer induce a surface tension, for wavelengths larger than the bilayer persistence length. The predictions of the model give a consistent account for both the wave vector and frequency dependence of the experimental data.

  5. Vascular calcium channels and high blood pressure: Pathophysiology and therapeutic implications

    PubMed Central

    Sonkusare, Swapnil; Palade, Philip T.; Marsh, James D.; Telemaque, Sabine; Pesic, Aleksandra; Rusch, Nancy J.

    2016-01-01

    Long-lasting Ca2+ (CaL) channels of the Cav1.2 gene family are heteromultimeric structures that are minimally composed of a pore-forming α1C subunit and regulatory β and α2δ subunits in vascular smooth muscle cells. The CaL channels are the primary pathways for voltage-gated Ca2+ influx that trigger excitation–contraction coupling in small resistance vessels. Notably, vascular smooth muscle cells of hypertensive rats show an increased expression of CaL channel α1C subunits, which is associated with elevated Ca2+ influx and the development of abnormal arterial tone. Indeed, blood pressure per se appears to promote CaL channel expression in small arteries, and even short-term rises in pressure may alter channel expression. Membrane depolarization has been shown to be one stimulus associated with elevated blood pressure that promotes CaL channel expression at the plasma membrane. Future studies to define the molecular processes that regulate CaL channel expression in vascular smooth muscle cells will provide a rational basis for designing antihypertensive therapies to normalize CaL channel expression and the development of anomalous vascular tone in hypertensive pathologies. PMID:16427812

  6. Relative changes of cerebral arterial and venous blood volumes during increased cerebral blood flow: implications for BOLD fMRI.

    PubMed

    Lee, S P; Duong, T Q; Yang, G; Iadecola, C; Kim, S G

    2001-05-01

    Measurement of cerebral arterial and venous blood volumes during increased cerebral blood flow can provide important information regarding hemodynamic regulation under normal, pathological, and neuronally active conditions. In particular, the change in venous blood volume induced by neural activity is one critical component of the blood oxygenation level-dependent (BOLD) signal because BOLD contrast is dependent only on venous blood, not arterial blood. Thus, relative venous and arterial blood volume (rCBV) and cerebral blood flow (rCBF) in alpha-chlorolase-anesthetized rats under hypercapnia were measured by novel diffusion-weighted (19)F NMR following an i.v. administration of intravascular tracer, perfluorocarbons, and continuous arterial spin labeling methods, respectively. The relationship between rCBF and total rCBV during hypercapnia was rCBV(total) = rCBF(0.40), which is consistent with previous PET measurement in monkeys. This relationship can be linearized in a CBF range of 50-130 ml/100 g/min as DeltarCBV(total)/ DeltarCBF = 0.31 where DeltarCBV and DeltarCBF represent rCBV and rCBF changes. The average arterial volume fraction was 0.25 at a basal condition with CBF of approximately 60 ml/100 g/min and increased up to 0.4 during hypercapnia. The change in venous rCBV was 2-fold smaller than that of total rCBV (DeltarCBV(vein)/DeltarCBF = 0.15), while the arterial rCBV change was 2.5 times larger than that of total rCBV (DeltarCBV(artery)/DeltarCBF = 0.79). These NMR results were confirmed by vessel diameter measurements with in vivo videomicroscopy. The absolute venous blood volume change contributes up to 36% of the total blood volume change during hypercapnia. Our findings provide a quantitative physiological model of BOLD contrast. PMID:11323805

  7. Determinants of resting cerebral blood flow in sickle cell disease.

    PubMed

    Bush, Adam M; Borzage, Matthew T; Choi, Soyoung; Václavů, Lena; Tamrazi, Benita; Nederveen, Aart J; Coates, Thomas D; Wood, John C

    2016-09-01

    Stroke is common in children with sickle cell disease and results from an imbalance in oxygen supply and demand. Cerebral blood flow (CBF) is increased in patients with sickle cell disease to compensate for their anemia, but adequacy of their oxygen delivery has not been systematically demonstrated. This study examined the physiological determinants of CBF in 37 patients with sickle cell disease, 38 ethnicity matched control subjects and 16 patients with anemia of non-sickle origin. Cerebral blood flow was measured using phase contrast MRI of the carotid and vertebral arteries. CBF increased inversely to oxygen content (r(2)  = 0.69, P < 0.0001). Brain oxygen delivery, the product of CBF and oxygen content, was normal in all groups. Brain composition, specifically the relative amounts of grey and white matter, was the next strongest CBF predictor, presumably by influencing cerebral metabolic rate. Grey matter/white matter ratio and CBF declined monotonically until the age of 25 in all subjects, consistent with known maturational changes in brain composition. Further CBF reductions were observed with age in subjects older than 35 years of age, likely reflecting microvascular aging. On multivariate regression, CBF was independent of disease state, hemoglobin S, hemoglobin F, reticulocyte count and cell free hemoglobin, suggesting that it is regulated similarly in patients and control subjects. In conclusion, sickle cell disease patients had sufficient oxygen delivery at rest, but accomplish this only by marked increases in their resting CBF, potentially limiting their ability to further augment flow in response to stress. Am. J. Hematol. 91:912-917, 2016. © 2016 Wiley Periodicals, Inc. PMID:27263497

  8. Effects of Poloxamer 188 on red blood cell membrane properties in sickle cell anaemia.

    PubMed

    Sandor, Barbara; Marin, Mickaël; Lapoumeroulie, Claudine; Rabaï, Miklos; Lefevre, Sophie D; Lemonne, Nathalie; El Nemer, Wassim; Mozar, Anaïs; Français, Olivier; Le Pioufle, Bruno; Connes, Philippe; Le Van Kim, Caroline

    2016-04-01

    Vaso-occlusive crisis (VOC) is the main acute complication in sickle cell anaemia (SS) and several clinical trials are investigating different drugs to improve the clinical severity of SS patients. A phase III study is currently exploring the profit of Velopoloxamer in SS during VOCs. We analysed, in-vitro, the effect of poloxamer (P188) on red blood cell (RBC) properties by investigating haemorheology, mechanical and adhesion functions using ektacytometry, microfluidics and dynamic adhesion approaches, respectively. We show that poloxamer significantly reduces blood viscosity, RBC aggregation and adhesion to endothelial cells, supporting the beneficial use of this molecule in SS therapy. PMID:26846309

  9. Efficient induction of pluripotent stem cells from menstrual blood.

    PubMed

    Li, Yang; Li, Xiaoni; Zhao, Hongxi; Feng, Ruopeng; Zhang, Xiaoyan; Tai, Dapeng; An, Guangyu; Wen, Jinhua; Tan, Jichun

    2013-04-01

    The technology to reprogram human somatic cells back to pluripotency allows the production of patient-specific induced pluripotent stem cells (iPSCs) and holds a great promise for regenerative medicine. Choosing the most suitable cell type for induction and reducing the risk of viral transgene activation, especially oncogene activation, are important for iPSC research. To date, human dermal fibroblasts (HDFs) are the most frequent cell source used for iPSC generation, but they have several limitations. An invasive skin biopsy must be performed to obtain HDFs, and HDFs must be cultured for a prolonged period before they can be used for experiments. Thus, in an effort to develop a suitable source for iPSC studies to avoid the limitations mentioned above, we have here identified stromal cells derived from menstrual blood (MenSCs) as suitable candidates. In the present study, we found that MenSCs can be reprogrammed to pluripotent status by doxycycline-inducible lentiviral transduction of OCT4, SOX2, and KLF4. Additionally, we found that MenSCs have a significantly higher reprogramming efficiency than HDFs. The combination of OCT4 and SOX2 is sufficient to reprogram MenSCs into iPSCs without the use of c-MYC or KLF4. The resulting MenSC-iPSCs showed the same characteristics as human embryonic stem cells with regard to morphology, pluripotent markers, gene expression, and the epigenetic status of pluripotent-cell-specific genes. These cells were able to differentiate into various cell types of all 3 germ layers both in vitro and in vivo. Therefore, MenSCs may be a preferred candidate for generation of iPSCs. PMID:23151296

  10. CD21(-/low) B cells in human blood are memory cells.

    PubMed

    Thorarinsdottir, K; Camponeschi, A; Cavallini, N; Grimsholm, O; Jacobsson, L; Gjertsson, I; Mårtensson, I-L

    2016-08-01

    The complement receptor 2 (CR2, CD21) is part of a complex (CD21/CD19/CD81) acting as a co-receptor to the B cell receptor (BCR). Simultaneous triggering of the BCR and CD21 lowers the threshold for B cell activation. Although CD21 is important, B cells that express low amounts or lack surface CD21 (CD21(-/low) ) are increased in conditions with chronic inflammation, e.g. autoimmune diseases. However, little is known about the CD21(-/low) B cell subset in peripheral blood from healthy donors. Here, we show that CD21(-/low) cells represent approximately 5% of B cells in peripheral blood from adults but are barely detectable in cord blood, after excluding transitional B cells. The CD21(-/low) subset can be divided into CD38(-) 24(+) and CD38(-) 24(low) cells, where most of the CD38(-) 24(+) are CD27(+) immunoglobulin (Ig)M(+) IgD(+) and the CD38(-) 24(low) are switched CD27(-) . Expression levels of additional markers, e.g. CD95 and CD62L, are similar to those on classical memory B cells. In contrast to naive cells, the majority of CD21(-/low) cells lack expression of the ABCB1 transporter. Stimulation with a combination of BCR, Toll-like receptor (TLR)-7/8 and interleukin (IL)-2 induces proliferation and differentiation of the CD21(-/low) B cells comparable to CD21(+) CD27(+) memory B cells. The response excluding BCR agonist is not on par with that of classical memory B cells, although clearly above that of naive B cells. This is ascribed to a weaker response by the CD38(-) 24(low) subset, implying that some memory B cells require not only TLR but also BCR triggering. We conclude that the CD21(-/low) cells in healthy donors are memory B cells. PMID:27010233

  11. Bioactive compounds from crocodile (Crocodylus siamensis) white blood cells induced apoptotic cell death in hela cells.

    PubMed

    Patathananone, Supawadee; Thammasirirak, Sompong; Daduang, Jureerut; Chung, Jing Gung; Temsiripong, Yosapong; Daduang, Sakda

    2016-08-01

    Crocodile (Crocodylus siamensis) white blood cell extracts (WBCex) were examined for anticancer activity in HeLa cell lines using the MTT assay. The percentage viability of HeLa cells significantly deceased after treatment with WBCex in a dose- and time-dependent manner. The IC50 dose was suggested to be approximately 225 μg/mL protein. Apoptotic cell death occurred in a time-dependent manner based on investigation by flow cytometry using annexin V-FITC and PI staining. DAPI nucleic acid staining indicated increased chromatin condensation. Caspase-3, -8 and -9 activities also increased, suggesting the induction of the caspase-dependent apoptotic pathway. Furthermore, the mitochondrial membrane potential (ΔΨm ) of HeLa cells was lost as a result of increasing levels of Bax and reduced levels of Bcl-2, Bcl-XL, Bcl-Xs, and XIAP. The decreased ΔΨm led to the release of cytochrome c and the activation of caspase-9 and -3. Apoptosis-inducing factor translocated into the nuclei, and endonuclease G (Endo G) was released from the mitochondria. These results suggest that anticancer agents in WBCex can induce apoptosis in HeLa cells via both caspase-dependent and -independent pathways. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 986-997, 2016. PMID:25691005

  12. A microfluidics approach for the isolation of nucleated red blood cells (NRBCs) from the peripheral blood of pregnant women

    PubMed Central

    Huang, R.; Barber, T. A.; Schmidt, M. A.; Tompkins, R. G.; Toner, M.; Bianchi, D. W.; Kapur, R.; Flejter, W. L.

    2015-01-01

    Objective Nucleated red blood cells (NRBCs) have been identified in maternal circulation and potentially provide a resource for the monitoring and diagnosis of maternal, fetal, and neonatal health and disease. Past strategies used to isolate and enrich for NRBCs are limited to complex approaches that result in low recovery and less than optimal cell purity. Here we report the development of a high-throughput and highly efficient microfluidic device for isolating rare NRBCs from maternal blood. Material and Methods NRBCs were isolated from the peripheral blood of 58 pregnant women using a microfluidic process that consists of a microfluidic chip for size-based cell separation and a magnetic device for hemoglobin-based cell isolation. Results The microfluidic–magnetic combination removes nontarget red blood cells and white blood cells at a very high efficiency (∼99.99%). The device successfully identified NRBCs from the peripheral blood of 58/58 pretermination samples with a mean of 37.44 NRBC/mL (range 0.37–274.36 NRBC/mL). These results were compared with those from previous studies. Conclusion The microfluidic device results in an approximate 10- to 20-fold enrichment of NRBCs over methods described previously. The reliability of isolation and the purity of the NRBC product have the potential to enable the subsequent application of molecular diagnostic assays. PMID:18821715

  13. Comparison of instruments for investigation of microcirculatory blood flow and red blood cell concentration

    NASA Astrophysics Data System (ADS)

    O'Doherty, Jim; McNamara, Paul; Clancy, Neil T.; Enfield, Joey G.; Leahy, Martin J.

    2009-05-01

    The use of laser Doppler perfusion imaging (LDPI) and laser speckle perfusion imaging (LSPI) is well known in the noninvasive investigation of microcirculatory blood flow. This work compares the two techniques with the recently developed tissue viability (TiVi) imaging system, which is proposed as a useful tool to quantify red blood cell concentration in microcirculation. Three systems are evaluated with common skin tests such as the use of vasodilating and vasoconstricting drugs (methlynicotinate and clobetasol, respectively) and a reactive hyperaemia maneuver (using a sphygmomanometer). The devices investigated are the laser Doppler line scanner (LDLS), the laser speckle perfusion imager (FLPI)-both from Moor Instruments (Axminster, United Kingdom)-and the TiVi imaging system (WheelsBridge AB, Linköping, Sweden). Both imaging and point scanning by the devices are used to quantify the provoked reactions. Perfusion images of vasodilatation and vasoconstriction are acquired with both LDLS and FLPI, while TiVi images are acquired with the TiVi imager. Time acquisitions of an averaged region of interest are acquired for temporal studies such as the reactive hyperaemia. In contrast to the change in perfusion over time with pressure, the TiVi imager shows a different response due its measurement of blood concentration rather than perfusion. The responses can be explained by physiological understanding. Although the three devices sample different compartments of tissue, and output essentially different variables, comparisons can be seen between the three systems. The LDLS system proves to be suited to measurement of perfusion in deeper vessels, while FLPI and TiVi showed sensitivity to more superficial nutritional supply. LDLS and FLPI are insensitive to the action of the vasoconstrictor, while TiVi shows the clear boundaries of the reaction. Assessment of the resolution, penetration depth, and acquisition rate of each instrument show complimentary features that should

  14. Blood analyte sensing using fluorescent dye-loaded red blood cells

    NASA Astrophysics Data System (ADS)

    Ritter, Sarah C.; Shao, Xiaole; Cooley, Nicholas; Milanick, Mark A.; Glass, Timothy E.; Meissner, Kenith E.

    2014-02-01

    Measurement of blood analytes provides crucial information about a patient's health. Some such analytes, such as glucose in the case of diabetes, require long-term or near-continuous monitoring for proper disease management. However, current monitoring techniques are far from ideal: multiple-per-day finger stick tests are inconvenient and painful for the patient; implantable sensors have short functional life spans (i.e., 3-7 days). Due to analyte transporters on red blood cell (RBC) membranes that equilibrate intracellular and extracellular analyte levels, RBCs serve as an attractive alternative for encapsulating analyte sensors. Once reintroduced to the blood stream, the functionalized RBCs may continue to live for the remainder of their life span (120 days for humans). They are biodegradable and biocompatible, thereby eliminating the immune system response common for many implanted devices. The proposed sensing system utilizes the ability of the RBCs to swell in response to a decrease in the osmolarity of the extracellular solution. Just before lysis, they develop small pores on the scale of tens of nanometers. While at low temperature, analyte-sensitive dyes in the extracellular solution diffuse into the perforated RBCs and become entrapped upon restoration of temperature and osmolarity. Since the fluorescent signal from the entrapped dye reports on changes in the analyte level of the extracellular solution via the RBC transporters, interactions between the RBCs and the dye are critical to the efficacy of this technique. In this work, we study the use of a near infrared pH sensitive dye encapsulated within RBCs and assess the ability to measure dye fluorescence in vivo.

  15. Therapeutic Implications of Leukemic Stem Cell Pathways

    PubMed Central

    Chumsri, Saranya; Matsui, William; Burger, Angelika M.

    2008-01-01

    An emerging concept in cancer biology is that a rare population of cancer stem cells exists among the heterogeneous cell mass that constitutes a tumor. This concept is best understood in human myeloid leukemia. Normal and malignant hematopoietic stem cell functions are defined by a common set of critical stemness genes that regulate self-renewal and developmental pathways. Several stemness factors, such as Notch or telomerase, show differential activation in normal hematopoietic versus leukemia stem cells. These differences could be exploited therapeutically even with drugs that are already in clinical use for the treatment of leukemia. The translation of novel and existing leukemic stem cell – directed therapies into clinical practice, however, will require changes in clinical trial design and the inclusion of stem cell biomarkers as correlative end points. PMID:18006753

  16. Cell differentiation mediated by co-culture of human umbilical cord blood stem cells with murine hepatic cells.

    PubMed

    Stecklum, Maria; Wulf-Goldenberg, Annika; Purfürst, Bettina; Siegert, Antje; Keil, Marlen; Eckert, Klaus; Fichtner, Iduna

    2015-02-01

    In the present study, purified human cord blood stem cells were co-cultivated with murine hepatic alpha mouse liver 12 (AML12) cells to compare the effect on endodermal stem cell differentiation by either direct cell-cell interaction or by soluble factors in conditioned hepatic cell medium. With that approach, we want to mimic in vitro the situation of preclinical transplantation experiments using human cells in mice. Cord blood stem cells, cultivated with hepatic conditioned medium, showed a low endodermal differentiation but an increased connexin 32 (Cx32) and Cx43, and cytokeratin 8 (CK8) and CK19 expression was monitored by reverse transcription polymerase chain reaction (RT-PCR). Microarray profiling indicated that in cultivated cord blood cells, 604 genes were upregulated 2-fold, with the highest expression for epithelial CK19 and epithelial cadherin (E-cadherin). On ultrastructural level, there were no major changes in the cellular morphology, except a higher presence of phago(ly)some-like structures observed. Direct co-culture of AML12 cells with cord blood cells led to less incisive differentiation with increased sex-determining region Y-box 17 (SOX17), Cx32 and Cx43, as well as epithelial CK8 and CK19 expressions. On ultrastructural level, tight cell contacts along the plasma membranes were revealed. FACS analysis in co-cultivated cells quantified dye exchange on low level, as also proved by time relapse video-imaging of labelled cells. Modulators of gap junction formation influenced dye transfer between the co-cultured cells, whereby retinoic acid increased and 3-heptanol reduced the dye transfer. The study indicated that the cell-co-cultured model of human umbilical cord blood cells and murine AML12 cells may be a suitable approach to study some aspects of endodermal/hepatic cell differentiation induction. PMID:25270685

  17. Adrenergic and non-adrenergic control of active skeletal muscle blood flow: implications for blood pressure regulation during exercise.

    PubMed

    Holwerda, Seth W; Restaino, Robert M; Fadel, Paul J

    2015-03-01

    Blood flow to active skeletal muscle increases markedly during dynamic exercise. However, despite the massive capacity of skeletal muscle vasculature to dilate, arterial blood pressure is well maintained. Sympathetic nerve activity is elevated with increased intensity of dynamic exercise, and is essential for redistribution of cardiac output to active skeletal muscle and maintenance of arterial blood pressure. In addition, aside from the sympathetic nervous system, evidence from human studies is now emerging that supports roles for non-adrenergic vasoconstrictor pathways that become active during exercise and contribute to vasoconstriction in active skeletal muscle. Neuropeptide Y and adenosine triphosphate are neurotransmitters that are co-released with norepinephrine from sympathetic nerve terminals capable of producing vasoconstriction. Likewise, plasma concentrations of arginine vasopressin, angiotensin II (Ang II) and endothelin-1 (ET-1) increase during dynamic exercise, particularly at higher intensities. Ang II and ET-1 have both been shown to be important vasoconstrictor pathways for restraint of blood flow in active skeletal muscle and the maintenance of arterial blood pressure during exercise. Indeed, although both adrenergic and non-adrenergic vasoconstriction can be attenuated in exercising muscle with greater intensity of exercise, with the higher volume of blood flow, the active skeletal muscle vasculature remains capable of contributing importantly to the maintenance of blood pressure. In this brief review we provide an update on skeletal muscle blood flow regulation during exercise with an emphasis on adrenergic and non-adrenergic vasoconstrictor pathways and their potential capacity to offset vasodilation and aid in the regulation of blood pressure. PMID:25467222

  18. Human Umbilical Cord Blood-Derived Serum for Culturing the Supportive Feeder Cells of Human Pluripotent Stem Cell Lines

    PubMed Central

    Rungsiwiwut, Ruttachuk; Ingrungruanglert, Praewphan; Numchaisrika, Pranee; Virutamasen, Pramuan; Phermthai, Tatsanee; Pruksananonda, Kamthorn

    2016-01-01

    Although human pluripotent stem cells (hPSCs) can proliferate robustly on the feeder-free culture system, genetic instability of hPSCs has been reported in such environment. Alternatively, feeder cells enable hPSCs to maintain their pluripotency. The feeder cells are usually grown in a culture medium containing fetal bovine serum (FBS) prior to coculture with hPSCs. The use of FBS might limit the clinical application of hPSCs. Recently, human cord blood-derived serum (hUCS) showed a positive effect on culture of mesenchymal stem cells. It is interesting to test whether hUCS can be used for culture of feeder cells of hPSCs. This study was aimed to replace FBS with hUCS for culturing the human foreskin fibroblasts (HFFs) prior to feeder cell preparation. The results showed that HFFs cultured in hUCS-containing medium (HFF-hUCS) displayed fibroblastic features, high proliferation rates, short population doubling times, and normal karyotypes after prolonged culture. Inactivated HFF-hUCS expressed important genes, including Activin A, FGF2, and TGFβ1, which have been implicated in the maintenance of hPSC pluripotency. Moreover, hPSC lines maintained pluripotency, differentiation capacities, and karyotypic stability after being cocultured for extended period with inactivated HFF-hUCS. Therefore, the results demonstrated the benefit of hUCS for hPSCs culture system. PMID:26839561

  19. 76 FR 3913 - Advisory Council on Blood Stem Cell Transplantation; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-21

    ... HUMAN SERVICES Health Resources and Services Administration Advisory Council on Blood Stem Cell... Advisory Council on Blood Stem Cell Transplantation (ACBSCT) Meeting to be Held by Conference Call. SUMMARY.... L. 92-463), notice is hereby given of the following meeting: Name: Advisory Council on Blood...

  20. 76 FR 62814 - Advisory Council on Blood Stem Cell Transplantation; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-11

    ... HUMAN SERVICES Health Resources and Services Administration Advisory Council on Blood Stem Cell... (Public Law 92-463), notice is hereby given of the following meeting: Name: Advisory Council on Blood Stem... amended,) the Advisory Council on Blood Stem Cell Transplantation (ACBSCT) advises the Secretary of...

  1. 78 FR 23571 - Advisory Council on Blood Stem Cell Transplantation; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-19

    ... HUMAN SERVICES Health Resources and Services Administration Advisory Council on Blood Stem Cell.... L. 92-463), notice is hereby given of the following meeting: Name: Advisory Council on Blood Stem... amended), the Advisory Council on Blood Stem Cell Transplantation (ACBSCT) advises the Secretary of...

  2. 78 FR 47714 - Advisory Council on Blood Stem Cell Transplantation; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-06

    ... HUMAN SERVICES Health Resources and Services Administration Advisory Council on Blood Stem Cell.... L. 92-463), notice is hereby given of the following meeting: Name: Advisory Council on Blood Stem... Health Service Act, as amended), the Advisory Council on Blood Stem Cell Transplantation (ACBSCT)...

  3. 76 FR 19101 - Advisory Council on Blood Stem Cell Transplantation; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-06

    ... HUMAN SERVICES Health Resources and Services Administration Advisory Council on Blood Stem Cell.... L. 92-463), notice is hereby given of the following meeting: ] Name: Advisory Council on Blood Stem... Health Service Act, as amended), the Advisory Council on Blood Stem Cell Transplantation (ACBSCT)...

  4. 77 FR 22791 - Advisory Council on Blood Stem Cell Transplantation; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-17

    ... HUMAN SERVICES Health Resources and Services Administration Advisory Council on Blood Stem Cell.... L. 92-463), notice is hereby given of the following meeting: Name: Advisory Council on Blood Stem... Health Service Act, as amended), the Advisory Council on Blood Stem Cell Transplantation (ACBSCT)...

  5. 78 FR 54257 - Advisory Council on Blood Stem Cell Transplantation; Request for Nominations for Voting Members

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-03

    ... HUMAN SERVICES Health Resources and Services Administration Advisory Council on Blood Stem Cell... requesting nominations of qualified candidates to fill expected vacancies on the Advisory Council on Blood.... Bill Young Cell Transplantation Program and the National Cord Blood Inventory Program. The ACBSCT...

  6. 75 FR 62843 - Advisory Council on Blood Stem Cell Transplantation; Notice of Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-13

    ... HUMAN SERVICES Health Resources and Services Administration Advisory Council on Blood Stem Cell.... L. 92-463), notice is hereby given of the following meeting: Name: Advisory Council on Blood Stem... Act, as amended) the Advisory Council on Blood Stem Cell Transplantation (ACBSCT) advises...

  7. Antibody-mediated red blood cell agglutination resulting in spontaneous echocardiographic contrast.

    PubMed

    Miller, M R; Thompson, W R; Casella, J F; Spevak, P J

    1999-01-01

    Spontaneous echocardiographic contrast is well reported in states of low flow and low shear stress, and the primary blood component involved has been reported as red blood cells via rouleaux formation. This report describes the occurrence of spontaneous echocardiographic contrast from a unique mechanism of IgM-mediated red blood cell agglutination and describes the clinical sequelae. PMID:10368455

  8. Secretome of Peripheral Blood Mononuclear Cells Enhances Wound Healing

    PubMed Central

    Haider, Thomas; Gschwandtner, Maria; Werba, Gregor; Barresi, Caterina; Zimmermann, Matthias; Golabi, Bahar; Tschachler, Erwin; Ankersmit, Hendrik Jan

    2013-01-01

    Non-healing skin ulcers are often resistant to most common therapies. Treatment with growth factors has been demonstrated to improve closure of chronic wounds. Here we investigate whether lyophilized culture supernatant of freshly isolated peripheral blood mononuclear cells (PBMC) is able to enhance wound healing. PBMC from healthy human individuals were prepared and cultured for 24 hours. Supernatants were collected, dialyzed and lyophilized (SECPBMC). Six mm punch biopsy wounds were set on the backs of C57BL/6J-mice and SECPBMC containing emulsion or controls were applied daily for three days. Morphology and neo-angiogenesis were analyzed by H&E-staining and CD31 immuno-staining, respectively. In vitro effects on diverse skin cells were investigated by migration assays, cell cycle analysis, and tube formation assay. Signaling pathways were analyzed by Western blot analysis. Application of SECPBMC on 6 mm punch biopsy wounds significantly enhanced wound closure. H&E staining of the wounds after 6 days revealed that wound healing was more advanced after application of SECPBMC containing emulsion. Furthermore, there was a massive increase in CD31 positive cells, indicating enhanced neo-angiogenesis. In primary human fibroblasts (FB) and keratinocytes (KC) migration but not proliferation was induced. In endothelial cells (EC) SECPBMC induced proliferation and tube-formation in a matrigel-assay. In addition, SECPBMC treatment of skin cells led to the induction of multiple signaling pathways involved in cell migration, proliferation and survival. In summary, we could show that emulsions containing the secretome of PBMC derived from healthy individuals accelerates wound healing in a mouse model and induce wound healing associated mechanisms in human primary skin cells. The formulation and use of such emulsions might therefore represent a possible novel option for the treatment of non-healing skin ulcers. PMID:23533667

  9. Anisotropic light scattering of individual sickle red blood cells

    NASA Astrophysics Data System (ADS)

    Kim, Youngchan; Higgins, John M.; Dasari, Ramachandra R.; Suresh, Subra; Park, YongKeun

    2012-04-01

    We present the anisotropic light scattering of individual red blood cells (RBCs) from a patient with sickle cell disease (SCD). To measure light scattering spectra along two independent axes of elongated-shaped sickle RBCs with arbitrary orientation, we introduce the anisotropic Fourier transform light scattering (aFTLS) technique and measured both the static and dynamic anisotropic light scattering. We observed strong anisotropy in light scattering patterns of elongated-shaped sickle RBCs along its major axes using static aFTLS. Dynamic aFTLS analysis reveals the significantly altered biophysical properties in individual sickle RBCs. These results provide evidence that effective viscosity and elasticity of sickle RBCs are significantly different from those of the healthy RBCs.

  10. Measurement of the nonlinear elasticity of red blood cell membranes

    NASA Astrophysics Data System (ADS)

    Park, Yongkeun; Best, Catherine A.; Kuriabova, Tatiana; Henle, Mark L.; Feld, Michael S.; Levine, Alex J.; Popescu, Gabriel

    2011-05-01

    The membranes of human red blood cells (RBCs) are a composite of a fluid lipid bilayer and a triangular network of semiflexible filaments (spectrin). We perform cellular microrheology using the dynamic membrane fluctuations of the RBCs to extract the elastic moduli of this composite membrane. By applying known osmotic stresses, we measure the changes in the elastic constants under imposed strain and thereby determine the nonlinear elastic properties of the membrane. We find that the elastic nonlinearities of the shear modulus in tensed RBC membranes can be well understood in terms of a simple wormlike chain model. Our results show that the elasticity of the spectrin network can mostly account for the area compression modulus at physiological osmolality, suggesting that the lipid bilayer has significant excess area. As the cell swells, the elastic contribution from the now tensed lipid membrane becomes dominant.

  11. Osmotic tolerance limits of red blood cells from umbilical cord blood.

    PubMed

    Zhurova, Mariia; Lusianti, Ratih E; Higgins, Adam Z; Acker, Jason P

    2014-08-01

    Effective methods for long-term preservation of cord red blood cells (RBCs) are needed to ensure a readily available supply of RBCs to treat fetal and neonatal anemia. Cryopreservation is a potential long-term storage strategy for maintaining the quality of cord RBCs for the use in intrauterine and neonatal transfusion. However, during cryopreservation, cells are subjected to damaging osmotic stresses during cryoprotectant addition and removal and freezing and thawing that require knowledge of osmotic tolerance limits in order to optimize the preservation process. The objective of this study was to characterize the osmotic tolerance limits of cord RBCs in conditions relevant to cryopreservation, and compare the results to the osmotic tolerance limits of adult RBCs. Osmotic tolerance limits were determined by exposing RBCs to solutions of different concentrations to induce a range of osmotic volume changes. Three treatment groups of adult and cord RBCs were tested: (1) isotonic saline, (2) 40% w/v glycerol, and (3) frozen-thawed RBCs in 40% w/v glycerol. We show that cord RBCs are more sensitive to shrinkage and swelling than adult RBCs, indicating that osmotic tolerance limits should be considered when adding and removing cryoprotectants. In addition, freezing and thawing resulted in both cord and adult RBCs becoming more sensitive to post-thaw swelling requiring that glycerol removal procedures for both cell types ensure that cell volume excursions are maintained below 1.7 times the isotonic osmotically active volume to attain good post-wash cell recovery. Our results will help inform the development of optimized cryopreservation protocol for cord RBCs. PMID:24836371

  12. Interleukin-4 receptors on human blood mononuclear cells

    SciTech Connect

    Zuber, C.E.; Galizzi, J.P.; Harada, N.; Durand, I.; Banchereau, J. )

    1990-09-01

    We have studied regulation of the expression of the interleukin-4 receptor (IL-4R) on human blood mononuclear cells (PBMC) using both 125I-IL-4 binding assay and flow cytometric analysis of biotinylated IL-4 (B-IL-4) binding. PBMC express approximately 300 high-affinity IL-4R per cell (Kd = 25-100 pM). Activation of PBMC for 60-80 hr by phytohemagglutinin (PHA) or concanavalin A (Con A) results in a 2- to 4.5-fold increase of IL-4R number without alteration of IL-4R affinity for IL-4. Binding of B-IL-4 showed that IL-4R expression is upregulated on virtually all PHA-stimulated PBMC, whereas it mostly concerns larger cells among Con A-activated PBMC. Reculture of PHA-blasts with 1 nM IL-4 further upregulates IL-4R expression to a level approximately 10-fold higher than observed on freshly isolated PBMC. Interestingly, IL-4 is able to reinduce high IL-4R levels on cells that have been deprived of IL-4 for 20 hr and IL-2 is almost as efficient. Finally, SDS-PAGE analysis of IL-4-binding molecules on unstimulated, PHA- and PHA/IL-4-activated PBMC revealed the same three peptides of MW 140-130, 80-75, and 70-65 kDa, as shown on human cell lines.

  13. Stretching and relaxation of malaria-infected red blood cells.

    PubMed

    Ye, Ting; Phan-Thien, Nhan; Khoo, Boo Cheong; Lim, Chwee Teck

    2013-09-01

    The invasion of red blood cells (RBCs) by malaria parasites is a complex dynamic process, in which the infected RBCs gradually lose their deformability and their ability to recover their original shape is greatly reduced with the maturation of the parasites. In this work, we developed two types of cell model, one with an included parasite, and the other without an included parasite. The former is a representation of real malaria-infected RBCs, in which the parasite is treated as a rigid body. In the latter, where the parasite is absent, the membrane modulus and viscosity are elevated so as to produce the same features present in the parasite model. In both cases, the cell membrane is modeled as a viscoelastic triangular network connected by wormlike chains. We studied the transient behaviors of stretching deformation and shape relaxation of malaria-infected RBCs based on these two models and found that both models can generate results in agreement with those of previously published studies. With the parasite maturation, the shape deformation becomes smaller and smaller due to increasing cell rigidity, whereas the shape relaxation time becomes longer and longer due to the cell's reduced ability to recover its original shape. PMID:24010653

  14. IMAGING RED BLOOD CELL DYNAMICS BY QUANTITATIVE PHASE MICROSCOPY

    PubMed Central

    Popescu, Gabriel; Park, YoungKeun; Choi, Wonshik; Dasari, Ramachandra R.; Feld, Michael S.; Badizadegan, Kamran

    2008-01-01

    Red blood cells (RBCs) play a crucial role in health and disease, and structural and mechanical abnormalities of these cells have been associated with important disorders such as Sickle cell disease and hereditary cytoskeletal abnormalities. Although several experimental methods exist for analysis of RBC mechanical properties, optical methods stand out as they enable collecting mechanical and dynamic data from live cells without physical contact and without the need for exogenous contrast agents. In this report, we present quantitative phase microscopy techniques that enable imaging RBC membrane fluctuations with nanometer sensitivity at arbitrary time scales from milliseconds to hours. We further provide a theoretical framework for extraction of membrane mechanical and dynamical properties using time series of quantitative phase images. Finally, we present an experimental approach to extend quantitative phase imaging to 3-dimensional space using tomographic methods. By providing non-invasive methods for imaging mechanics of live cells, these novel techniques provide an opportunity for high-throughput analysis and study of RBC mechanical properties in health and disease. PMID:18387320

  15. A look inside the mechanistic black box: Are red blood cells the critical effectors of RRx-001 cytotoxicity?

    PubMed

    Cabrales, Pedro; Scicinski, Jan; Reid, Tony; Kuypers, Frans; Larkin, Sandra; Fens, Marcel; Oronsky, Arnold; Oronsky, Bryan

    2016-07-01

    The therapeutic potential of epi-immunotherapeutic anticancer agent RRx-001 in cancer has been validated with preclinical and clinical studies, since RRx-001 has successfully completed a phase 1 trial and multiple single-agent and combination phase 2 trials with preliminary evidence of promising activity are underway. Previous experimental work has implicated diverse anticancer mechanisms such as oxidative stress, ATP and NADPH depletion, anti-angiogenesis and epigenetic modulation in the overall antitumor effect of RRx-001. The hypothesis of this study was that the RRx-001 red blood cells are the essential and de facto intermediaries responsible for the reprograming of tumor behavior via transfer of their intracellular and membrane contents. To test this hypothesis, and thereby resolve the "black box" incompleteness in the continuity of the mechanism, the fate of red blood cells incubated with RRx-001 was explored in vitro and in vivo both in healthy animals and in tumor-bearing mice. The collective results establish that RRx-001-derivatized red blood cells are the critical "missing links" to explain the specificity and anticancer activity of RRx-001, including its immunomodulatory effects on tumor-associated macrophages. These experimental results delineate a novel erythrocyte-based mechanism without precedent in the annals of oncology and open the door to rational combination strategies with RRx-001 both in cancer therapy and beyond, particularly in disease states that affect red blood cell and vascular function such as malaria, leishmaniasis, sickle-cell disease and hemorrhagic shock. PMID:27229330

  16. Variation of red blood cell distribution width and mean platelet volume after moderate endurance exercise.

    PubMed

    Lippi, Giuseppe; Salvagno, Gian Luca; Danese, Elisa; Tarperi, Cantor; Guidi, Gian Cesare; Schena, Federico

    2014-01-01

    Although physical exercise strongly influences several laboratory parameters, data about the hematological changes after medium distance running are scarce. We studied 31 middle-trained athletes (mean training regimen 217 ± 32 min/week) who performed a 21.1 km, half-marathon run. Blood samples were collected before the run, at the end, and 3 and 20 hours thereafter. The complete blood count was performed on Advia 2120 and included red blood cell (RBC), reticulocyte, and platelet counts; hemoglobin; mean corpuscular volume (MCV); mean corpuscular hemoglobin (MCH); reticulocyte haemoglobin content (Ret CHR); RBC distribution width (RDW), mean platelet volume (MPV). No significant variations were observed for MCH and Ret CHR. The RBC, reticulocyte, and hemoglobin values modestly decreased after the run. The MCV significantly increased at the end of running but returned to baseline 3 hours thereafter. The RDW constantly increased, reaching a peak 20 hours after the run. The platelet count and MPV both increased after the run and returned to baseline 3 hours thereafter. These results may have implications for definition of reference ranges and antidoping testing, and may also contribute to explaining the relationship between endurance exercise and mortality, since previous studies reported that RDW and MPV may be significantly associated with cardiovascular disease. PMID:25197280

  17. Bio-inspired Cryo-ink Preserves Red Blood Cell Phenotype and Function during Nanoliter Vitrification

    PubMed Central

    Assal, Rami El; Guven, Sinan; Gurkan, Umut Atakan; Gozen, Irep; Shafiee, Hadi; Dalbeyber, Sedef; Abdalla, Noor; Thomas, Gawain; Fuld, Wendy; Illigens, Ben M.W.; Estanislau, Jessica; Khoory, Joseph; Kaufman, Richard; Zylberberg, Claudia; Lindeman, Neal; Wen, Qi; Ghiran, Ionita; Demirci, Utkan

    2014-01-01

    Current red blood cell cryopreservation methods utilize bulk volumes, causing cryo-injury of cells, which results in irreversible disruption of cell morphology, mechanics, and function. An innovative approach to preserve human red blood cell morphology, mechanics, and function following vitrification in nanoliter volumes is developed using a novel cryo-ink integrated with a bio-printing approach. PMID:25047246

  18. Red blood cell cluster separation from digital images for use in sickle cell disease.

    PubMed

    González-Hidalgo, Manuel; Guerrero-Peña, F A; Herold-García, S; Jaume-I-Capó, Antoni; Marrero-Fernández, P D

    2015-07-01

    The study of cell morphology is an important aspect of the diagnosis of some diseases, such as sickle cell disease, because red blood cell deformation is caused by these diseases. Due to the elongated shape of the erythrocyte, ellipse adjustment and concave point detection are applied widely to images of peripheral blood samples, including during the detection of cells that are partially occluded in the clusters generated by the sample preparation process. In the present study, we propose a method for the analysis of the shape of erythrocytes in peripheral blood smear samples of sickle cell disease, which uses ellipse adjustments and a new algorithm for detecting notable points. Furthermore, we apply a set of constraints that allow the elimination of significant image preprocessing steps proposed in previous studies. We used three types of images to validate our method: artificial images, which were automatically generated in a random manner using a computer code; real images from peripheral blood smear sample images that contained normal and elongated erythrocytes; and synthetic images generated from real isolated cells. Using the proposed method, the efficiency of detecting the two types of objects in the three image types exceeded 99.00%, 98.00%, and 99.35%, respectively. These efficiency levels were superior to the results obtained with previously proposed methods using the same database, which is available at http://erythrocytesidb.uib.es/. This method can be extended to clusters of several cells and it requires no user inputs. PMID:25216490

  19. Imaging morphodynamics of human blood cells in vivo with video-rate third harmonic generation microscopy

    PubMed Central

    Chen, Chien-Kuo; Liu, Tzu-Ming

    2012-01-01

    With a video-rate third harmonic generation (THG) microscopy system, we imaged the micro-circulation beneath the human skin without labeling. Not only the speed of circulation but also the morpho-hydrodynamics of blood cells can be analyzed. Lacking of nuclei, red blood cells (RBCs) shows typical parachute-like and hollow-core morphology under THG microscopy. Quite different from RBCs, every now and then, round and granule rich blood cells with strong THG contrast appear in circulation. The corresponding volume densities in blood, evaluated from their frequencies of appearance and the velocity of circulation, fall within the physiological range of human white blood cell counts. PMID:23162724

  20. Imaging morphodynamics of human blood cells in vivo with video-rate third harmonic generation microscopy.

    PubMed

    Chen, Chien-Kuo; Liu, Tzu-Ming

    2012-11-01

    With a video-rate third harmonic generation (THG) microscopy system, we imaged the micro-circulation beneath the human skin without labeling. Not only the speed of circulation but also the morpho-hydrodynamics of blood cells can be analyzed. Lacking of nuclei, red blood cells (RBCs) shows typical parachute-like and hollow-core morphology under THG microscopy. Quite different from RBCs, every now and then, round and granule rich blood cells with strong THG contrast appear in circulation. The corresponding volume densities in blood, evaluated from their frequencies of appearance and the velocity of circulation, fall within the physiological range of human white blood cell counts. PMID:23162724

  1. Emerging microengineering tools for functional analysis and phenotyping of blood cells

    PubMed Central

    Li, Xiang; Chen, Weiqiang; Li, Zida; Li, Ling; Gu, Hongchen; Fu, Jianping

    2014-01-01

    The available techniques for assessing blood cell functions are limited considering the various types of blood cells and their diverse functions. In the past decade, rapid advancement in microengineering has enabled an array of blood cell functional measurements that are difficult or impossible to achieve using conventional bulk platforms. Such miniaturized blood cell assay platforms also provide attractive capabilities of reducing chemical consumption, cost, assay time, as well as exciting opportunities of device integration, automation, and assay standardization. This review summarizes these contemporary microengineering tools and discusses their promising potential for constructing accurate in vitro models and rapid clinical diagnosis using minimal amount of whole blood samples. PMID:25283971

  2. Detection and quantification of subtle changes in red blood cell density using a cell phone.

    PubMed

    Felton, Edward J; Velasquez, Anthony; Lu, Shulin; Murphy, Ryann O; ElKhal, Abdala; Mazor, Ofer; Gorelik, Pavel; Sharda, Anish; Ghiran, Ionita C

    2016-08-16

    Magnetic levitation has emerged as a technique that offers the ability to differentiate between cells with different densities. We have developed a magnetic levitation system for this purpose that distinguishes not only different cell types but also density differences in cells of the same type. This small-scale system suspends cells in a paramagnetic medium in a capillary placed between two rare earth magnets, and cells levitate to an equilibrium position determined solely by their density. Uniform reference beads of known density are used in conjunction with the cells as a means to quantify their levitation positions. In one implementation images of the levitating cells are acquired with a microscope, but here we also introduce a cell phone-based device that integrates the magnets, capillary, and a lens into a compact and portable unit that acquires images with the phone's camera. To demonstrate the effectiveness of magnetic levitation in cell density analysis we carried out levitation experiments using red blood cells with artificially altered densities, and also levitated those from donors. We observed that we can distinguish red blood cells of an anemic donor from those that are healthy. Since a plethora of disease states are characterized by changes in cell density magnetic cell levitation promises to be an effective tool in identifying and analyzing pathologic states. Furthermore, the low cost, portability, and ease of use of the cell phone-based system may potentially lead to its deployment in low-resource environments. PMID:27431921

  3. Recent Stem Cell Advances: Cord Blood and Induced Pluripotent Stem Cell for Cardiac Regeneration- a Review.

    PubMed

    Medhekar, Sheetal Kashinath; Shende, Vikas Suresh; Chincholkar, Anjali Baburao

    2016-05-30

    Stem cells are primitive self renewing undifferentiated cell that can be differentiated into various types of specialized cells like nerve cell, skin cells, muscle cells, intestinal tissue, and blood cells. Stem cells live in bone marrow where they divide to make new blood cells and produces peripheral stem cells in circulation. Under proper environment and in presence of signaling molecules stem cells begin to develop into specialized tissues and organs. These unique characteristics make them very promising entities for regeneration of damaged tissue. Day by day increase in incidence of heart diseases including left ventricular dysfunction, ischemic heart disease (IHD), congestive heart failure (CHF) are the major cause of morbidity and mortality. However infracted tissue cannot regenerate into healthy tissue. Heart transplantation is only the treatment for such patient. Due to limitation of availability of donor for organ transplantation, a focus is made for alternative and effective therapy to treat such condition. In this review we have discussed the new advances in stem cells such as use of cord stem cells and iPSC technology in cardiac repair. Future approach of CB cells was found to be used in tissue repair which is specifically observed for improvement of left ventricular function and myocardial infarction. Here we have also focused on how iPSC technology is used for regeneration of cardiomyocytes and intiating neovascularization in myocardial infarction and also for study of pathophysiology of various degenerative diseases and genetic disease in research field. PMID:27426082

  4. Recent Stem Cell Advances: Cord Blood and Induced Pluripotent Stem Cell for Cardiac Regeneration- a Review

    PubMed Central

    Medhekar, Sheetal Kashinath; Shende, Vikas Suresh; Chincholkar, Anjali Baburao

    2016-01-01

    Stem cells are primitive self renewing undifferentiated cell that can be differentiated into various types of specialized cells like nerve cell, skin cells, muscle cells, intestinal tissue, and blood cells. Stem cells live in bone marrow where they divide to make new blood cells and produces peripheral stem cells in circulation. Under proper environment and in presence of signaling molecules stem cells begin to develop into specialized tissues and organs. These unique characteristics make them very promising entities for regeneration of damaged tissue. Day by day increase in incidence of heart diseases including left ventricular dysfunction, ischemic heart disease (IHD), congestive heart failure (CHF) are the major cause of morbidity and mortality. However infracted tissue cannot regenerate into healthy tissue. Heart transplantation is only the treatment for such patient. Due to limitation of availability of donor for organ transplantation, a focus is made for alternative and effective therapy to treat such condition. In this review we have discussed the new advances in stem cells such as use of cord stem cells and iPSC technology in cardiac repair. Future approach of CB cells was found to be used in tissue repair which is specifically observed for improvement of left ventricular function and myocardial infarction. Here we have also focused on how iPSC technology is used for regeneration of cardiomyocytes and intiating neovascularization in myocardial infarction and also for study of pathophysiology of various degenerative diseases and genetic disease in research field. PMID:27426082

  5. A multi-laboratory comparison of blood dendritic cell populations

    PubMed Central

    Fromm, Phillip Dieter; Kupresanin, Fiona; Brooks, Anna Elizabeth Stella; Dunbar, Peter Rodney; Haniffa, Muzifilla; Hart, Derek Nigel John; Clark, Georgina Jane

    2016-01-01

    HLDA10 collated a panel of monoclonal antibodies (mAbs) that primarily recognised molecules on human myeloid cell and dendritic cell (DC) populations. As part of the studies, we validated a backbone of mAbs to delineate monocyte and DC populations from peripheral blood. The mAb backbone allowed identification of monocyte and DC subsets using fluorochromes that were compatible with most ‘off the shelf' or routine flow cytometers. Three laboratories used this mAb backbone to assess the HLDA10 panel on blood monocytes and DCs. Each laboratory was provided with enough mAbs to perform five repeat experiments. The data were collated and analysed using Spanning-tree Progression Analysis of Density-normalised Events (SPADE). The data were interrogated for inter- and intra-laboratory variability. The results highlight the definition of DC populations using current readily available reagents. This collaborative process provides the broader scientific community with an invaluable data set that validates mAbs to leucocyte surface molecules. PMID:27195111

  6. Red blood cell distribution width and cardiovascular diseases

    PubMed Central

    Danese, Elisa; Lippi, Giuseppe

    2015-01-01

    Background The red blood cell distribution width (RDW) is a rather simple measure of red blood cell (RBC) size heterogeneity (i.e., anisocytosis), which is easily calculated by dividing the standard deviation (SD) of erythrocyte volumes for the mean corpuscular volume (MCV). Emerging evidence suggests that, besides RBC abnormalities, many human disorders may be frequently associated with a high degree of anisocytosis. Methods In this narrative review, we analyzed the current scientific literature about the putative role and the potential epidemiologic association between RDW and cardiovascular diseases. The findings of the most representative epidemiological studies were summarized and discussed. Results Overall, considerable and convincing evidence has been brought that an increased RDW value is associated with acute coronary syndrome (ACS) [including acute myocardial infarction (AMI)], ischemic cerebrovascular disease (including stroke), peripheral artery disease (PAD), as well as with atrial fibrillation (AF), heart failure (HF) and hypertension. Higher anisocytosis also significantly and independently predicts adverse outcomes in patients with these conditions. Conclusions Although the role of anisocytosis in the pathogenesis of cardiovascular diseases remains uncertain, the considerable evidence available so far suggests that the clinical use of RDW may be broadened beyond the conventional boundaries of erythrocyte disorders, in particular for assisting the diagnosis and prognostication of patients with ACS, ischemic cerebrovascular disease, PAD, HF and AF. PMID:26623117

  7. The aging of the red blood cell. A multifactor process.

    PubMed

    Danon, D; Marikovsky, Y

    1988-01-01

    Red blood cell (rbc) senescence is associated with loss of surface sialic acid, which is the principal carrier of surface negative charge and determines the electrokinetic behavior of old rbcs. Loss of sialic acid in an old rbc is demonstrated in its decreased electric mobility and lower negative charge density, determined topographically with cationic particle labeling. Surface sialic acid determines also the mutual attraction--repulsion forces, as demonstrated in enhanced aggluinability with cationic molecules, lectins, and blood group antibodies. Loss of sialic acid accompanies ATP-depletion in vitro; thus, a T-antigen site is unmasked. Macrophages have specific receptors to the site as to newly exposed galactose and N-acetyl galactosamine sugars. Furthermore, the involvement of complement molecules in the recognition of old RBCs by macrophages has been shown. This is possibly due to loss of sialic acid or at least a regrouping--relocation of surface anionic sites due to cell shape changes from discocytes to crenated forms, which accompany both in vivo and in vitro rbc aging. In turn, shape changes are apparently controlled by the cytoskeletal network underlying the rbc membrane, which undergoes structural alteration with physiologic aging in changing the dimensions of oligomeric spectrin and the thickness of the spectrin-actin cytoskeletal assembly. PMID:3052636

  8. Assaying Blood Cell Populations of the Drosophila melanogaster Larva

    PubMed Central

    Petraki, Sophia; Alexander, Brandy; Brückner, Katja

    2015-01-01

    In vertebrates, hematopoiesis is regulated by inductive microenvironments (niches). Likewise, in the invertebrate model organism Drosophila melanogaster, inductive microenvironments known as larval Hematopoietic Pockets (HPs) have been identified as anatomical sites for the development and regulation of blood cells (hemocytes), in particular of the self-renewing macrophage lineage. HPs are segmentally repeated pockets between the epidermis and muscle layers of the larva, which also comprise sensory neurons of the peripheral nervous system. In the larva, resident (sessile) hemocytes are exposed to anti-apoptotic, adhesive and proliferative cues from these sensory neurons and potentially other components of the HPs, such as the lining muscle and epithelial layers. During normal development, gradual release of resident hemocytes from the HPs fuels the population of circulating hemocytes, which culminates in the release of most of the resident hemocytes at the beginning of metamorphosis. Immune assaults, physical injury or mechanical disturbance trigger the premature release of resident hemocytes into circulation. The switch of larval hemocytes between resident locations and circulation raises the need for a common standard/procedure to selectively isolate and quantify these two populations of blood cells from single Drosophila larvae. Accordingly, this protocol describes an automated method to release and quantify the resident and circulating hemocytes from single larvae. The method facilitates ex vivo approaches, and may be adapted to serve a variety of developmental stages of Drosophila and other invertebrate organisms. PMID:26650404

  9. Role of white blood cells in filtration of blood cell suspensions.

    PubMed

    Chien, S; Schmalzer, E A; Lee, M M; Impelluso, T; Skalak, R

    1983-01-01

    The time-dependent filtration pressure curves of cell suspensions pumped through 5 microns polycarbonate filters at a constant flow rate were analyzed with the aid of a theoretical model developed in an accompanying paper. The cell suspensions contained mixtures of erythrocytes and leukocytes, the concentrations of which were systematically varied. The pressure-time (P-t) curves generally showed multiphasic components. Following the attainment of a quasi-steady state level, the pressure rose first rapidly and then more slowly. The rates of pressure rise in the fast and slow phases were normalized by using the steady state pressure reading (PO) obtained with Ringer solution at the same flow rate, and are designated k1 and k2, respectively. Both k1 and k2 increased with rising concentrations of leukocytes, [WBC], or erythrocytes, [RBC]. [WBC] is 700-1000 times more effective than [RBC] in affecting k1 and k2. k1 is related to the dynamic plugging and unplugging of filter pores, primarily by leukocytes. k2 is attributable to the "permanent" plugging of filter pores, again predominantly by leukocytes. The experimental P-t curves can be fitted with the theoretical model by using appropriate constants for leukocyte plugging. The results indicate that nearly 2/3 of the entering leukocytes cause transient plugging of pores, with an unplugging rate of 4.1 percent/sec/unit pressure rise, and that approximately 2.2 percent of the entering leukocytes are "permanently" lodged. These results underscore the important role of leukocytes in determining the later phase of the P-t curve and support the concept that leukocyte plugging may have pathophysiological significance in causing microvascular occlusion in disease states. PMID:6871423

  10. Implications of MMP9 for Blood Brain Barrier Disruption and Hemorrhagic Transformation Following Ischemic Stroke

    PubMed Central

    Turner, Renée J.; Sharp, Frank R.

    2016-01-01

    Numerous studies have documented increases in matrix metalloproteinases (MMPs), specifically MMP-9 levels following stroke, with such perturbations associated with disruption of the blood brain barrier (BBB), increased risk of hemorrhagic complications, and worsened outcome. Despite this, controversy remains as to which cells release MMP-9 at the normal and pathological BBB, with even less clarity in the context of stroke. This may be further complicated by the influence of tissue plasminogen activator (tPA) treatment. The aim of the present review is to examine the relationship between neutrophils, MMP-9 and tPA following ischemic stroke to elucidate which cells are responsible for the increases in MMP-9 and resultant barrier changes and hemorrhage observed following stroke. PMID:26973468

  11. Sickle cell disease biochip: a functional red blood cell adhesion assay for monitoring sickle cell disease.

    PubMed

    Alapan, Yunus; Kim, Ceonne; Adhikari, Anima; Gray, Kayla E; Gurkan-Cavusoglu, Evren; Little, Jane A; Gurkan, Umut A

    2016-07-01

    Sickle cell disease (SCD) afflicts millions of people worldwide and is associated with considerable morbidity and mortality. Chronic and acute vaso-occlusion are the clinical hallmarks of SCD and can result in pain crisis, widespread organ damage, and early movtality. Even though the molecular underpinnings of SCD were identified more than 60 years ago, there are no molecular or biophysical markers of disease severity that are feasibly measured in the clinic. Abnormal cellular adhesion to vascular endothelium is at the root of vaso-occlusion. However, cellular adhesion is not currently evaluated clinically. Here, we present a clinically applicable microfluidic device (SCD biochip) that allows serial quantitative evaluation of red blood cell (RBC) adhesion to endothelium-associated protein-immobilized microchannels, in a closed and preprocessing-free system. With the SCD biochip, we have analyzed blood samples from more than 100 subjects and have shown associations between the measured RBC adhesion to endothelium-associated proteins (fibronectin and laminin) and individual RBC characteristics, including hemoglobin content, fetal hemoglobin concentration, plasma lactate dehydrogenase level, and reticulocyte count. The SCD biochip is a functional adhesion assay, reflecting quantitative evaluation of RBC adhesion, which could be used at baseline, during crises, relative to various long-term complications, and before and after therapeutic interventions. PMID:27063958

  12. Sickle cell disease biochip: a functional red blood cell adhesion assay for monitoring sickle cell disease

    PubMed Central

    ALAPAN, YUNUS; KIM, CEONNE; ADHIKARI, ANIMA; GRAY, KAYLA E.; GURKAN-CAVUSOGLU, EVREN; LITTLE, JANE A.; GURKAN, UMUT A.

    2016-01-01

    Sickle cell disease (SCD) afflicts millions of people worldwide and is associated with considerable morbidity and mortality. Chronic and acute vaso-occlusion are the clinical hallmarks of SCD and can result in pain crisis, widespread organ damage, and early movtality. Even though the molecular underpinnings of SCD were identified more than 60 years ago, there are no molecular or biophysical markers of disease severity that are feasibly measured in the clinic. Abnormal cellular adhesion to vascular endothelium is at the root of vaso-occlusion. However, cellular adhesion is not currently evaluated clinically. Here, we present a clinically applicable microfluidic device (SCD biochip) that allows serial quantitative evaluation of red blood cell (RBC) adhesion to endothelium-associated protein-immobilized microchannels, in a closed and preprocessing-free system. With the SCD biochip, we have analyzed blood samples from more than 100 subjects and have shown associations between the measured RBC adhesion to endothelium-associated proteins (fibronectin and laminin) and individual RBC characteristics, including hemoglobin content, fetal hemoglobin concentration, plasma lactate dehydrogenase level, and reticulocyte count. The SCD biochip is a functional adhesion assay, reflecting quantitative evaluation of RBC adhesion, which could be used at baseline, during crises, relative to various long-term complications, and before and after therapeutic interventions. PMID:27063958

  13. Mechanisms of cell death in acute myocardial infarction: pathophysiological implications for treatment

    PubMed Central

    de Zwaan, C.; Daemen, M.J.A.P.; Hermens, W.Th.

    2001-01-01

    The purpose of this review is to draw attention to the growing list of pathophysiological phenomena occurring in blood, the vessel wall and cardiac tissue during myocardial infarction. A further aim is to point to the complexity of factors, contributing to cardiac dysfunction and the implications for therapy, aimed at limiting myocardial cell death. Not all pathophysiological mechanisms have been elucidated yet, indicating the necessity for further research in this area. In addition we describe interventions which have shown promise in animal studies, those which may show promise in humans, and those which are accepted as therapies of choice. PMID:25696691

  14. Could Cord Blood Cell Therapy Reduce Preterm Brain Injury?

    PubMed Central

    Li, Jingang; McDonald, Courtney A.; Fahey, Michael C.; Jenkin, Graham; Miller, Suzanne L.

    2014-01-01

    Major advances in neonatal care have led to significant improvements in survival rates for preterm infants, but this occurs at a cost, with a strong causal link between preterm birth and neurological deficits, including cerebral palsy (CP). Indeed, in high-income countries, up to 50% of children with CP were born preterm. The pathways that link preterm birth and brain injury are complex and multifactorial, but it is clear that preterm birth is strongly associated with damage to the white matter of the developing brain. Nearly 90% of preterm infants who later develop spastic CP have evidence of periventricular white matter injury. There are currently no treatments targeted at protecting the immature preterm brain. Umbilical cord blood (UCB) contains a diverse mix of stem and progenitor cells, and is a particularly promising source of cells for clinical applications, due to ethical and practical advantages over other potential therapeutic cell types. Recent studies have documented the potential benefits of UCB cells in reducing brain injury, particularly in rodent models of term neonatal hypoxia–ischemia. These studies indicate that UCB cells act via anti-inflammatory and immuno-modulatory effects, and release neurotrophic growth factors to support the damaged and surrounding brain tissue. The etiology of brain injury in preterm-born infants is less well understood than in term infants, but likely results from episodes of hypoperfusion, hypoxia–ischemia, and/or inflammation over a developmental period of white matter vulnerability. This review will explore current knowledge about the neuroprotective actions of UCB cells and their potential to ameliorate preterm brain injury through neonatal cell administration. We will also discuss the characteristics of UCB-derived from preterm and term infants for use in clinical applications. PMID:25346720

  15. Fetal anaemia from red blood cell membrane defect and co-inherited haemoglobin Constant Spring.

    PubMed

    Srisupundit, Kasemsri; Charoenkwan, Pimlak; Traisrisilp, Kuntharee; Tongsong, Theera

    2015-01-01

    The case presented here is an example of hereditary red blood cell membrane defect with a co-inherited haemoglobin Constant Spring. This case is of an anaemic fetus that presented with isolated ascites at 18 weeks of gestation. Fetal blood analysis revealed abnormal shaped red blood cells. The same pattern of red blood cell morphology was also seen on paternal peripheral blood smear. Intrauterine blood transfusions were given twice to correct fetal anaemia. The fetus showed a good response to the transfusions and was delivered at term with mild anaemia and did not need blood transfusion after birth. This report describes a natural course of red blood cell membrane defect with co-inherited haemoglobin Constant Spring, indicating that the course of disease was more severe during fetal life. Intrauterine transfusion supported the transition of the fetus through the critical period in utero to a healthier life after birth. PMID:26216922

  16. Freezing of living cells: mechanisms and implications

    SciTech Connect

    Mazur, P.

    1984-01-01

    Cells can endure storage at low temperatures such as -196/sup 0/C for centuries. The challenge is to determine how they can survive both the cooling to such temperatures and the subsequent return to physiological conditions. A major factor is whether they freeze intracellularly. They do so if cooling is too rapid, because with rapid cooling insufficient cell water is removed osmotically to eliminate supercooling. Equations have been developed that describe the kinetics of this water loss and permit one to predict the likelihood of intracellular freezing as a function of cooling rate. Such predictions agree well with observations. Although the avoidance of intracellular freezing is usually necessary for survival, it is not sufficient. Slow freezing itself can be injurious. As ice forms outside the cell, the residual unfrozen medium forms channels of decreasing size and increasing solute concentration. The cells lie in the channels and shrink in osmotic response to the rising solute concentration. Prior theories have ascribed slow freezing injury to the concentration of solutes or the cell shrinkage. Recent experiments, however, indicate that the damage is due more to the decrease in the size of the unfrozen channels. This new view of the mechanism of slow freezing injury ought to facilitate the development of procedures for the preservation of complex assemblages of cells of biological, medical, and agricultural significance. 126 references, 18 figures, 2 tables.

  17. Cerebral blood flow in sickle cell cerebrovascular disease

    SciTech Connect

    Huttenlocher, P.R.; Moohr, J.W.; Johns, L.; Brown, F.D.

    1984-05-01

    Cerebral blood flow (CBF) has been studied by the xenon-133 (/sup 133/Xe) inhalation method in 16 children with suspected sickle cell cerebrovascular disease. Abnormalities consisting of decreases in total, hemispheral, or regional CBF were found in 17 of 26 studies. Eleven studies performed immediately after stroke, transient ischemic attack, or depression of state of alertness showed abnormalities. In addition to confirming regional cerebrovascular insufficiency in children with stroke due to major cerebral artery occlusion, the method detected diffuse decrease in CBF in children with stupor, coma, and seizures who had normal angiographic findings. In contrast, six of seven studies obtained after exchange transfusion or during maintenance on hypertransfusion therapy showed normal findings. The difference between results in patients with acute neurologic disturbances and those receiving transfusion therapy was statistically significant (P less than .005). The data indicate that the /sup 133/Xe method reliably demonstrates cerebrovascular impairment in sickle cell disease. They also suggest that CBF changes in patients with sickle cell disease can be reversed by exchange transfusion and by hypertransfusion therapy. The /sup 133/Xe CBF method may be useful for following up children with sickle cell disease who are at high risk for recurrent stroke.

  18. Hypochromicity in red blood cells: an experimental and theoretical investigation

    PubMed Central

    Nonoyama, Akihisa; Garcia-Lopez, Alicia; Garcia-Rubio, Luis H.; Leparc, German F.; Potter, Robert L.

    2011-01-01

    Multiwavelength UV-visible transmission spectrophotometry is a useful tool for the examination of micron-size particle suspensions in the context of particle size and chemical composition. This paper reports the reliability of this method to characterize the spectra of purified red blood cells both in their physiological state and with modified hemoglobin content. Previous studies have suggested the contribution of hypochromism on the particle spectra caused by the close electronic interaction of the encapsulated chromophores. Our research shows, however, that this perceived hypochromism can be accounted for by considering two important issues: the acceptance angle of the instrument and the combined scattering and absorption effect of light on the particles. In order to establish these ideas, spectral analysis was performed on purified and modified red cells where the latter was accomplished with a modified hypotonic shock protocol that altered the hemoglobin concentration within the cells. Moreover, the Mie theory was used to successfully simulate the spectral features and trends of the red cells. With this combination of experimental and theoretical exploration, definition of hypochromism has been extended to two subcategories. PMID:21833353

  19. Modeling of Red Blood Cells and Related Spleen Function

    NASA Astrophysics Data System (ADS)

    Peng, Zhangli; Pivkin, Igor; Dao, Ming

    2011-11-01

    A key function of the spleen is to clear red blood cells (RBCs) with abnormal mechanical properties from the circulation. These abnormal mechanical properties may be due to RBC aging or RBC diseases, e.g., malaria and sickle cell anemia. Specifically, 10% of RBCs passing through the spleen are forced to squeeze into the narrow slits between the endothelial cells, and stiffer cells which get stuck are killed and digested by macrophages. To investigate this important physiological process, we employ three different approaches to study RBCs passage through these small slits, including analytical theory, Dissipative Particle Dynamics (DPD) simulation and Multiscale Finite Element Method (MS-FEM). By applying the analytical theory, we estimate the critical limiting geometries RBCs can pass. By using the DPD method, we study the full fluid-structure interaction problem, and compute RBC deformation under different pressure gradients. By employing the MS-FEM approach, we model the lipid bilayer and the cytoskeleton as two distinct layers, and focus on the cytoskeleton deformation and the bilayer-skeleton interaction force at the molecular level. Finally the results of these three approaches are compared to each other and correlated to the experimental observations.

  20. The CD8+ granzyme B+ T-cell subset in peripheral blood from healthy individuals contains activated and apoptosis-prone cells.

    PubMed Central

    Wever, P C; Van Der Vliet, H J; Spaeny, L H; Wolbink, A M; Van Diepen, F N; Froelich, C J; Hack, C E; ten Berge, I J

    1998-01-01

    Granzyme B (GrB) has been implicated in induction of apoptosis in target cells. The presence of GrB in peripheral blood CD8+ T cells from healthy individuals was analysed in immunocytochemical and flow cytometric studies. Furthermore, CD8+ GrB- T cells and CD8+ GrB+ T cells were compared regarding phenotypical characteristics and susceptibility to both spontaneous and Fasmediated apoptosis. GrB was expressed by approximately one-fifth of CD8+ T cells. Compared with the CD8+ GrB- T-cell subset, the CD8+ GrB+ T-cell subset contained cells that were relatively more activated and more prone to spontaneous apoptosis. Culturing of cells with immunoglobulin M (IgM) anti-Fas monoclonal antibody had no additional effect on the number of CD8+ GrB+ T cells undergoing apoptosis. We suggest that the presence of CD8+ GrB+ T cells in peripheral blood from healthy individuals results from immune surveillance or contact with infectious agents, and that spontaneous apoptosis of these cells might serve as a mechanism for their eventual clearance. Images Figure 1 PMID:9640249

  1. Colloidal Properties of Nanoerythrosomes Derived from Bovine Red Blood Cells.

    PubMed

    Kuo, Yuan-Chia; Wu, Hsuan-Chen; Hoang, Dao; Bentley, William E; D'Souza, Warren D; Raghavan, Srinivasa R

    2016-01-12

    Liposomes are nanoscale containers that are typically synthesized from lipids using a high-shear process such as extrusion or sonication. While liposomes are extensively used in drug delivery, they do suffer from certain problems including limited colloidal stability and short circulation times in the body. As an alternative to liposomes, we explore a class of container structures derived from erythrocytes (red blood cells). The procedure involves emptying the inner contents of these cells (specifically hemoglobin) and resuspending the empty structures in buffer, followed by sonication. The resulting structures are termed nanoerythrosomes (NERs), i.e., they are membrane-covered nanoscale containers, much like liposomes. Cryo-transmission electron microscopy (cryo-TEM) and small-angle neutron scattering (SANS) are employed for the first time to study these NERs. The results reveal that the NERs are discrete spheres (∼110 nm diameter) with a unilamellar membrane of thickness ∼4.5 nm. Remarkably, the biconcave disc-like shape of erythrocytes is also exhibited by the NERs under hypertonic conditions. Moreover, unlike typical liposomes, NERs show excellent colloidal stability in both buffer as well as in serum at room temperature, and are also able to withstand freeze-thaw cycling. We have explored the potential for using NERs as colloidal vehicles for targeted delivery. Much like conventional liposomes, NER membranes can be decorated with fluorescent or other markers, solutes can be encapsulated in the cores of the NERs, and NERs can be targeted to specifically bind to mammalian cells. Our study shows that NERs are a promising and versatile class of nanostructures. NERs that are harvested from a patient's own blood and reconfigured for nanomedicine can potentially offer several benefits including biocompatibility, minimization of immune response, and extended circulation time in the body. PMID:26684218

  2. Adipose-derived stem cells: Implications in tissue regeneration

    PubMed Central

    Tsuji, Wakako; Rubin, J Peter; Marra, Kacey G

    2014-01-01

    Adipose-derived stem cells (ASCs) are mesenchymal stem cells (MSCs) that are obtained from abundant adipose tissue, adherent on plastic culture flasks, can be expanded in vitro, and have the capacity to differentiate into multiple cell lineages. Unlike bone marrow-derived MSCs, ASCs can be obtained from abundant adipose tissue by a minimally invasive procedure, which results in a high number of cells. Therefore, ASCs are promising for regenerating tissues and organs damaged by injury and diseases. This article reviews the implications of ASCs in tissue regeneration. PMID:25126381

  3. Gene Expression Profile in Peripheral Blood Cells of Friedreich Ataxia Patients.

    PubMed

    Abrahao, Agessandro; Pedroso, Jose Luiz; de Carvalho Aguiar, Patricia Maria; Barsottini, Orlando Graziani Povoas

    2016-06-01

    Friedreich ataxia (FRDA) is the most common autosomal recessive ataxia characterized by a combination of neurological involvement, cardiomyopathy, and skeletal and glucose metabolism disturbances. FRDA is caused by mutations in FXN gene that results in reduction of mRNA and protein levels of frataxin. Previous microarray and real-time quantitative PCR (qPCR) studies showed that the downregulation of FXN is associated with a complex gene expression profile. However, these studies showed a wide variability in the subset of genes with altered expression among tissues and models. Genes differentially expressed in peripheral blood cells (PBC) could potentially help in the understanding of FRDA pathophysiology and also function as reliable disease biomarkers obtained from an easily accessible tissue, which could have implications in clinical practice. This study aimed to validate by qPCR the expression of 26 genes, revealed as differentially expressed by other studies, using peripheral blood cells (PBC) of 11 FRDA patients compared to 11 healthy controls. We found a robust downregulation of FXN, but no statistically significant differences were found between FRDA and controls for the remaining genes. Except for FXN, our study did not find a differential gene expression profile in PBC of FRDA patients and a reliable gene expression profile biomarker in a clinical relevant and noninvasive tissue remains unclear. PMID:26170003

  4. Counting White Blood Cells from a Blood Smear Using Fourier Ptychographic Microscopy.

    PubMed

    Chung, Jaebum; Ou, Xiaoze; Kulkarni, Rajan P; Yang, Changhuei

    2015-01-01

    White blood cell (WBC) count is a valuable metric for assisting with diagnosis or prognosis of various diseases such as coronary heart disease, type 2 diabetes, or infection. Counting WBCs can be done either manually or automatically. Automatic methods are capable of counting a large number of cells to give a statistically more accurate reading of the WBC count of a sample, but the specialized equipment tends to be expensive. Manual methods are inexpensive since they only involve a conventional light microscope setup. However, it is more laborious and error-prone because the small field-of-view (FOV) of the microscope necessitates mechanical scanning of a specimen for counting an adequate number of WBCs. Here, we investigate the use of Fourier ptychographic microscopy (FPM) to bypass these issues of the manual methods. With a 2x objective, FPM can provide a FOV of 120 mm2 with enhanced resolution comparable to that of a 20x objective, which is adequate for non-differentially counting WBCs in just one FOV. A specialist was able to count the WBCs in FPM images with 100% accuracy compared to the count as determined from conventional microscope images. An automatic counting algorithm was also developed to identify WBCs from FPM's captured images with 95% accuracy, paving the way for a cost-effective WBC counting setup with the advantages of both the automatic and manual counting methods. PMID:26186353

  5. An artificial blood vessel implanted three-dimensional microsystem for modeling transvascular migration of tumor cells.

    PubMed

    Wang, Xue-Ying; Pei, Ying; Xie, Min; Jin, Zi-He; Xiao, Ya-Shi; Wang, Yang; Zhang, Li-Na; Li, Yan; Huang, Wei-Hua

    2015-02-21

    Reproducing a tumor microenvironment consisting of blood vessels and tumor cells for modeling tumor invasion in vitro is particularly challenging. Here, we report an artificial blood vessel implanted 3D microfluidic system for reproducing transvascular migration of tumor cells. The transparent, porous and elastic artificial blood vessels are obtained by constructing polysaccharide cellulose-based microtubes using a chitosan sacrificial template, and possess excellent cytocompatibility, permeability, and mechanical characteristics. The artificial blood vessels are then fully implanted into the collagen matrix to reconstruct the 3D microsystem for modeling transvascular migration of tumor cells. Well-defined simulated vascular lumens were obtained by proliferation of the human umbilical vein endothelial cells (HUVECs) lining the artificial blood vessels, which enables us to reproduce structures and functions of blood vessels and replicate various hemodynamic parameters. Based on this model, the adhesion and transvascular migration of tumor cells across the artificial blood vessel have been well reproduced. PMID:25565271

  6. [The dynamics of the rapid changes in the phospholipids of the whole blood and blood cells in patients with endometriosis interna].

    PubMed

    Kulakov, V I; Sliusar', N N; Bakuleva, L P; Damirov, M M; Kargapolov, A V

    1993-01-01

    Time course of rapid changes in blood phospholipids and blood cells was studied in 44 patients with endometriosis. Rapid reversible blood phospholipid changes were observed when these patients' red cells and lymphocytes were incubated with calcium chloride. Time course of rapid changes in phosphoinosites, sphyngomyelines, phosphatidylserines, phosphlatidylethanolamines of patients' red and white blood cells, whole blood, and myometrial tissue differed significantly from that in healthy women. The authors suppose that cellular proliferation processes in endometriosis are connected with phospholipid homeostasis disorders in blood cells and tissue. PMID:8250135

  7. EVALUATION OF RED BLOOD CELL INDICES RELATED DISORDERS AMONG ELIGIBLE BLOOD DONORS AT THE UNIVERSITI PUTRA MALAYSIA (UPM).

    PubMed

    Riahi, Shahrzad; Mei, I Lai; Idris, Fariddh Binti; George, Elizabeth; Noor, Sabariah Md

    2015-09-01

    Pre-donation screening declarations and hemoglobin (Hb) testing are measures used to determine the quality of donated blood. The copper sulphate (CuSo4) method used to screen for blood abnormalities can give inaccurate results if strict quality control is not applied. Blood donors who are carriers of thalassemia and those with mild iron deficiency anemia (IDA) are usually asymptomatic and frequently missed at blood donation. The aim of this study was to evaluate the red blood cell (RBC) indices related disorders among blood donors who were deemed qualified to donate blood after screening with CuSo4 method. One hundred fifty-eight volunteer blood donors at the Universiti Putra Malaysia (UPM), who had passed the CuSo4 screening method, were recruited for this study. Their bloods specimens were examined with a complete blood count. Subjects with a low mean corpuscular hemoglobin (MCH) level were examined further by checking a serum ferritin level, Hb quantification, and molecular analysis to examine for common RBC disorders. Fourteen point six percent of subjects had a low Hb level, two (1.3%) had IDA and four (2.5%) had thalassemia or some other hemoglobinopathy. Using a MCH level < 27 pg as a cut-off point, 58 subjects (36.7%) had suspected IDA, thalassemia or some other hemoglobinopathy. Eight point nine percent of subjects with a normal Hb level had thalassemia, and 3.8% had IDA. Malaysia has a high prevalence of thalassemia and other hemoglobinopathies. Pre-donation accurate screening is crucial to protect the quality of blood transfusion products. Public education regarding RBC disorders especially among blood donors is important. PMID:26863862

  8. Assessment of leucoreduction of sickle cell trait blood: quality of the filtered product

    PubMed Central

    Amar, Karim Ould; Bourdonné, Olivier; Bruneau, Sylvie; Sellami, Fatiha; Richard, Pascale

    2014-01-01

    Background With the implementation of universal leucoreduction of blood components in several industrialised countries, the problems associated with leucocyte filtration of sickle cell trait blood have been reconsidered. In this study, we assessed the use of high performance filters for leucoreduction of packed red blood cells donated from subjects with sickle cell trait and evaluated the incidence and recurrence of altered red blood cell filterability. Materials and methods Twenty-one volunteer donors with HbAS were compared to 21 donors with HbAA selected at random. The main parameters analysed were residual white blood cell count and post-filtration haemolysis. Filtration times, flow, volume and haemoglobin loss of the packed red blood cells were also determined. Results In all, 33% of HbAS red blood cell units with slow flow and prolonged filtration time had high residual white blood cell counts. In 7.7% of cases, despite flow through the filter, the units were not leucoreduced properly. Haemoglobin and volume loss were significantly greater in the slow filtration group. Significant post-filtration haemolysis was present in half of the units with high residual white blood cell counts. Discussion Despite the development of new technology for filtration, the problem of filterability of blood from donors with sickle cell trait is not yet resolved. Altered filterability of blood from sickle cell trait donors cannot be predicted from the donors’ characteristics and recurrence of the problem is not observed between donations. Screening blood donors for sickle cell trait to ensure the safety and quality of blood products for transfusion does, therefore, remain a relevant issue. PMID:23149143

  9. All in the Blood: A Review of Aboriginal Australians' Cultural Beliefs About Blood and Implications for Biospecimen Research.

    PubMed

    Kowal, Emma; Greenwood, Ashley; McWhirter, Rebekah E

    2015-10-01

    Public participation in medical research and biobanking is considered key to advances in scientific discovery and translation to improved health care. Cultural concerns relating to blood have been found to affect the participation of indigenous peoples and minorities in research, but such concerns are rarely specified in the literature. This article presents a review of the role of blood in Australian Aboriginal cultures. We discuss the range of meanings and uses of blood in traditional culture, including their use in ceremonies, healing, and sorcery. We draw on more recent literature on Aboriginal Australians and biomedicine to consider how traditional beliefs may be changing over time. These findings provide an empirical basis for researchers and bioethicists to develop culturally grounded strategies to boost the participation of Aboriginal Australians in biomedical research. They also serve as a model for integrating anthropological literature with bioethical concerns that could be applied to other indigenous and minority groups. PMID:26376752

  10. Current issues relating to the transfusion of stored red blood cells.

    PubMed

    Zimrin, A B; Hess, J R

    2009-02-01

    The development of blood storage systems allowed donation and transfusion to be separated in time and space. This separation has permitted the regionalization of donor services with subsequent economies of scale and improvements in the quality and availability of blood products. However, the availability of storage raises the question of how long blood products can and should be stored and how long they are safe and effective. The efficacy of red blood cells was originally measured as the increment in haematocrit and safety began with typing and the effort to reduce the risk of bacterial contamination. Appreciation of a growing list of storage lesions of red blood cells has developed with our increasing understanding of red blood cell physiology and our experience with red blood cell transfusion. However, other than frank haemolysis, rare episodes of bacterial contamination and overgrowth, the reduction of oxygen-carrying capacity associated with the failure of some transfused cells to circulate, and the toxicity of lysophospholipids released from membrane breakdown, storage-induced lesions have not had obvious correlations with safety or efficacy. The safety of red blood cell storage has also been approached in retrospective epidemiologic studies of transfused patients, but the results are frequently biased by the fact that sicker patients are transfused more often and blood banks do not issue blood products in a random order. Several large prospective studies of the safety of stored red blood cells are planned. PMID:19152602

  11. Cell–cell interaction networks regulate blood stem and progenitor cell fate

    PubMed Central

    Kirouac, Daniel C; Madlambayan, Gerard J; Yu, Mei; Sykes, Edward A; Ito, Caryn; Zandstra, Peter W

    2009-01-01

    Communication networks between cells and tissues are necessary for homeostasis in multicellular organisms. Intercellular (between cell) communication networks are particularly relevant in stem cell biology, as stem cell fate decisions (self-renewal, proliferation, lineage specification) are tightly regulated based on physiological demand. We have developed a novel mathematical model of blood stem cell development incorporating cell-level kinetic parameters as functions of secreted molecule-mediated intercellular networks. By relation to quantitative cellular assays, our model is capable of predictively simulating many disparate features of both normal and malignant hematopoiesis, relating internal parameters and microenvironmental variables to measurable cell fate outcomes. Through integrated in silico and experimental analyses, we show that blood stem and progenitor cell fate is regulated by cell–cell feedback, and can be controlled non-cell autonomously by dynamically perturbing intercellular signalling. We extend this concept by demonstrating that variability in the secretion rates of the intercellular regulators is sufficient to explain heterogeneity in culture outputs, and that loss of responsiveness to cell–cell feedback signalling is both necessary and sufficient to induce leukemic transformation in silico. PMID:19638974

  12. Neonatal nucleated red blood cells in G6PD deficiency.

    PubMed

    Yeruchimovich, Mark; Shapira, Boris; Mimouni, Francis B; Dollberg, Shaul

    2002-05-01

    The objective of this study is to study the absolute number of nucleated red blood cells (RBC) at birth, an index of active fetal erythropoiesis, in infants with G6PD deficiency and in controls. We tested the hypothesis that hematocrit and hemoglobin would be lower, and absolute nucleated RBC counts higher, in the G6PD deficient and that these changes would be more prominent in infants exposed passively to fava bean through maternal diet. Thirty-two term infants with G6PD deficiency were compared with 30 term controls. Complete blood counts with manual differential counts were obtained within 12 hours of life. Absolute nucleated RBC and corrected leukocyte counts were computed from the Coulter results and the differential count. G6PD deficient patients did not differ from controls in terms of gestational age, birth weight, or Apgar scores or in any of the hematologic parameters studied, whether or not the mother reported fava beans consumption in the days prior to delivery. Although intrauterine hemolysis is possible in G6PD deficient fetuses exposed passively to fava beans, our study supports that such events must be very rare. PMID:12012283

  13. Perioperative Red Blood Cell Transfusion: What We Do Not Know

    PubMed Central

    Lei, Chong; Xiong, Li-Ze

    2015-01-01

    Objective: Blood transfusion saves lives but may also increase the risk of injury. The objective of this review was to evaluate the possible adverse effects related to transfusion of red blood cell (RBC) concentrates stored for prolonged periods. Data Sources: The data used in this review were mainly from PubMed articles published in English up to February 2015. Study Selection: Clinical and basic research articles were selected according to their relevance to this topic. Results: The ex vivo changes to RBC that occur during storage are collectively called storage lesion. It is still inconclusive if transfusion of RBC with storage lesion has clinical relevance. Multiple ongoing prospective randomized controlled trials are aimed to clarify this clinical issue. It was observed that the adverse events related to stored RBC transfusion were prominent in certain patient populations, including trauma, critical care, pediatric, and cardiac surgery patients, which leads to the investigation of underlying mechanisms. It is demonstrated that free hemoglobin toxicity, decreasing of nitric oxide bioavailability, and free iron-induced increasing of inflammation may play an important role in this process. Conclusion: It is still unclear whether transfusion of older RBC has adverse effects, and if so, which factors determine such clinical effects. However, considering the magnitude of transfusion and the widespread medical significance, potential preventive strategies should be considered, especially for the susceptible recipients. PMID:26315088

  14. Red blood cell deformability in diabetes mellitus: effect of phytomenadione.

    PubMed

    Sabo, A; Jakovljević, V; Stanulović, M; Lepsanović, L; Pejin, D

    1993-01-01

    Decreased deformability of red blood cells (RBC) in diabetes mellitus (DM) is considered to be linked to microcirculatory complications in this condition. As we found that phytomenadione increased RBC deformability in experimental animals, the question was raised, whether phytomenadione had the same effect on the RBC of diabetic patients. The study was performed in 10 patients with insulin-dependent diabetes mellitus, where the erythrocyte deformability was impaired. Patients received 10 mg/day phytomenadione i.m. for five days. Deformability was measured with policarbonate membranes (Nucleopore) with pore diameter 5 microns, under gravity. The results were expressed as the ratio (r) between the flow of 1.5 ml (r1) and 2 ml (r2) of RBC suspension and 1.5 ml of buffer. Phytomenadione increased the erythrocyte deformability in patients with diabetes mellitus, lowering the value r1 from 3.54 +/- 0.84 to 2.32 +/- 0.61 (p 0.02) and r2 from 7.80 +/- 2.41 to 4.65 +/- 1.07 (p 0.01). The values after treatment reached the range of healthy controls (r1 3.11 +/- 0.98, r2 6.52 +/- 3.04). The whole blood viscosity was significantly lowered after phytomenadione (5.28 +/- 0.58 mPas before, 4.64 +/- 0.74 mPas after, p < 0.02) with unchanged plasma viscosity, but significantly lowered internal viscosity of erythrocytes. PMID:8444511

  15. Sensitivity of Hematocrit to Osmotic Effects Induced by Changes in Dialysate Conductivity: Implications for Relative Blood Volume Measurement and Control.

    PubMed

    Schneditz, Daniel; Schilcher, Gernot; Ribitsch, Werner; Zierler, Edda; Jantscher, Andreas

    2015-01-01

    Hemodialysis is accompanied by osmotic perturbations with distinct effects on red blood cell, plasma, and blood volumes. A series of in vitro studies was done to analyze the separate effect on cell volume. Whole porcine blood was circulated through an extracorporeal circulation maintaining a constant blood volume. Hemoconcentration was continuously measured by established optical and ultrasonic online techniques. Osmotic perturbation was performed by variation of dialysate conductivity within the clinical range of 13-15 mS/cm. Blood samples were analyzed using a microcentrifuge and a standard cell counter. As dialysate conductivity increased, centrifuge hematocrit (in %) decreased with a slope of -1.91% per unit of conductivity in mS/cm (r2 = 0.98). At the same time, Coulter-Counter hematocrit slightly decreased only by -0.18% (r2 = 0.53), while optical and ultrasonic hematocrit showed a small increase by 0.44% (r2 = 0.97) and 0.69% (r2 = 0.94) per unit of conductivity in mS/cm. The sensitivity to osmotic perturbation is consistent with theory and with specific characteristics of measuring techniques used in this study. The differences, however, need to be considered when comparing measurements obtained by different techniques. Finally, devices used for relative blood volume measurement in hemodialysis should be insensitive to osmosis-induced changes in red blood cell volume. PMID:24561459

  16. Of macrophages and red blood cells; a complex love story.

    PubMed

    de Back, Djuna Z; Kostova, Elena B; van Kraaij, Marian; van den Berg, Timo K; van Bruggen, Robin

    2014-01-01

    Macrophages tightly control the production and clearance of red blood cells (RBC). During steady state hematopoiesis, approximately 10(10) RBC are produced per hour within erythroblastic islands in humans. In these erythroblastic islands, resident bone marrow macrophages provide erythroblasts with interactions that are essential for erythroid development. New evidence suggests that not only under homeostasis but also under stress conditions, macrophages play an important role in promoting erythropoiesis. Once RBC have matured, these cells remain in circulation for about 120 days. At the end of their life span, RBC are cleared by macrophages residing in the spleen and the liver. Current theories about the removal of senescent RBC and the essential role of macrophages will be discussed as well as the role of macrophages in facilitating the removal of damaged cellular content from the RBC. In this review we will provide an overview on the role of macrophages in the regulation of RBC production, maintenance and clearance. In addition, we will discuss the interactions between these two cell types during transfer of immune complexes and pathogens from RBC to macrophages. PMID:24523696

  17. Cytoskeletal control of the red-blood cell membrane

    NASA Astrophysics Data System (ADS)

    Gov, Nir; Safran, Sam

    2004-03-01

    We have shown (Physical Review Letters, 90, 228101 (2003)) that the thermal fluctuations of red blood cells can be accounted for by a model of a nearly-free, but confined bilayer membrane with a finite tension; both the confinement and tension arise from the coupling of the membrane with the cytoskeleton. Recently, we have shown that these relatively gentle effects of the cytoskeleton-membrane couplings on the membrane fluctuations are due to the dilute nature of the coupling molecules. To quantify this, we predict the fluctuation amplitude for a microscopic model of the inhomogeneous coupling of a fluid membrane and a fixed cytoskeleton. The coupling is modeled as periodic and harmonic, and we consider the linear response of the membrane. We find that there is indeed, an effective surface tension and confinement of such a membrane, in accord with our phenomenological model, and relate these quantities to the strength and periodicity of the microscopic coupling. We also find, surprisingly, that the membrane can develop a spontaneous breaking of the cytoskeleton symmetry, at low confinements. Finally we address the role of ATP activity on the cytoskeleton-driven fluctuations and the equilibrium shape of the cell. We examine in detail the role of spectrin disconnections as the main ATP-activated network defects on the global cell shape and membrane fluctuations.

  18. Loss of deformability of malaria-infected red blood cells

    NASA Astrophysics Data System (ADS)

    Hosseini, S. Majid; Feng, James

    2012-11-01

    The pathogenesis of malaria is largely due to stiffening of the infected red blood cells (RBCs). Contemporary understanding ascribes the loss of RBC deformability to a 10-fold increase in membrane stiffness caused by extra cross-linking in the spectrin network. Local measurements by micropipette aspiration, however, have reported only an increase of 3-fold in the shear modulus. We believe the discrepancy stems from the rigid parasite particles inside infected cells, and have carried out numerical simulations to demonstrate this mechanism. The cell membrane is represented by a set of discrete particles connected by linearly elastic springs. The cytosol is modeled as a homogeneous Newtonian fluid, and discretized by particles as in standard smoothed particle hydrodynamics. The malaria parasite is modeled as an aggregate of particles constrained to rigid-body motion. We simulate RBC stretching tests by optical tweezers in three dimensions. The results demonstrate that the presence of a sizeable parasite greatly reduces the ability of RBCs to deform under stretching. With the solid inclusion, the observed loss of deformability can be predicted quantitatively using the local membrane elasticity measured by micropipettes.

  19. Cost-effective and Rapid Blood Analysis on a Cell-phone

    PubMed Central

    Zhu, Hongying; Sencan, Ikbal; Wong, Justin; Dimitrov, Stoyan; Tseng, Derek; Nagashima, Keita; Ozcan, Aydogan

    2013-01-01

    We demonstrate a compact and cost-effective imaging cytometry platform installed on a cell-phone for the measurement of the density of red and white blood cells as well as hemoglobin concentration in human blood samples. Fluorescent and bright-field images of blood samples are captured using separate optical attachments to the cell-phone and are rapidly processed through a custom-developed smart application running on the phone for counting of blood cells and determining hemoglobin density. We evaluated the performance of this cell-phone based blood analysis platform using anonymous human blood samples and achieved comparable results to a standard bench-top hematology analyser. Test results can either be stored on the cell-phone memory or be transmitted to a central server, providing remote diagnosis opportunities even in field settings. PMID:23392286

  20. Iron-Deficiency Anemia Enhances Red Blood Cell Oxidative Stress

    PubMed Central

    Nagababu, Enika; Gulyani, Seema; Earley, Christopher J.; Cutler, Roy G.; Mattson, Mark P.; Rifkind, Joseph M.

    2009-01-01

    Oxidative stress associated with iron deficiency anemia in a murine model was studied feeding an iron deficient diet. Anemia was monitored by a decrease in hematocrit and hemoglobin. For the 9 week study an increase in total iron binding capacity was also demonstrated. Anemia resulted in an increase in red blood cells (RBC) oxidative stress as indicated by increased levels of fluorescent heme degradation products (1.24 fold after 5 weeks; 2.1 fold after 9 weeks). The increase in oxidative stress was further confirmed by elevated levels of methemoglobin for mice fed an iron deficient diet. Increased hemoglobin autoxidation and subsequent generation of ROS can account for the shorter RBC lifespan and other pathological changes associated with iron deficiency anemia. PMID:19051108

  1. Dynamics of flat membranes and flickering in red blood cells

    NASA Astrophysics Data System (ADS)

    Frey, Erwin; Nelson, David R.

    1991-12-01

    A theory of the dynamics of polymerized membranes in the flat phase is presented. The dynamics of dilute membrane solutions is strongly influenced by long-ranged hydrodynamic interactions among the monomers, mediated by the intervening solvent. We discuss the renormalization of the kinetic coefficients for the undulation and phonon modes due to hydrodynamic “backflow” (Zimm behavior). The dynamics is also studied for free draining membranes (Rouse dynamics) corresponding to the Brownian dynamics method used in Monte Carlo simulations. The long time behavior of the dynamic structure factor is given by stretched exponentials with stretching exponents determined by the exponents of the elastic coefficients and the wave vector dependence of the Oseen tensor. We also study the dynamics of the thickness fluctuations in red blood cells (flicker phenomenon) taking into account the underlying polymerized spectrin skeleton. Qualitatively different dynamical behavior is predicted for spectrin skeletons isolated from heir natural lipid environment.

  2. Reprogramming committed murine blood cells to induced hematopoietic stem cells with defined factors

    PubMed Central

    Riddell, Jonah; Gazit, Roi; Garrison, Brian S.; Guo, Guoji; Saadatpour, Assieh; Mandal, Pankaj K.; Ebina, Wataru; Volchkov, Pavel; Yuan, Guo-Cheng; Orkin, Stuart H.; Rossi, Derrick J.

    2014-01-01

    Hematopoietic stem cells (HSCs) sustain blood formation throughout life and are the functional units of bone marrow transplantation. We show that transient expression of six transcription factors RUNX1T1, HLF, LMO2, PRDM5, PBX1, and ZFP37 imparts multi-lineage transplantation potential onto otherwise committed lymphoid and myeloid progenitors, and myeloid effector cells. Inclusion of MYC-N and MEIS1, and use of polycistronic viruses increase reprogramming efficacy. The reprogrammed cells, designated induced-HSCs (iHSCs), possess clonal multi-lineage differentiation potential, reconstitute stem/progenitor compartments, and are serially transplantable. Single-cell analysis revealed that iHSCs derived under optimal conditions exhibit a gene expression profile that is highly similar to endogenous HSCs. These findings demonstrate that expression of a set of defined factors is sufficient to activate the gene networks governing HSC functional identity in committed blood cells. Our results raise the prospect that blood cell reprogramming may be a strategy for derivation of transplantable stem cells for clinical application. PMID:24766805

  3. The Blood-Testis Barrier and Its Implications for Male Contraception

    PubMed Central

    Mruk, Dolores D.

    2012-01-01

    The blood-testis barrier (BTB) is one of the tightest blood-tissue barriers in the mammalian body. It divides the seminiferous epithelium into the basal and the apical (adluminal) compartments. Meiosis I and II, spermiogenesis, and spermiation all take place in a specialized microenvironment behind the BTB in the apical compartment, but spermatogonial renewal and differentiation and cell cycle progression up to the preleptotene spermatocyte stage take place outside of the BTB in the basal compartment of the epithelium. However, the BTB is not a static ultrastructure. Instead, it undergoes extensive restructuring during the seminiferous epithelial cycle of spermatogenesis at stage VIII to allow the transit of preleptotene spermatocytes at the BTB. Yet the immunological barrier conferred by the BTB cannot be compromised, even transiently, during the epithelial cycle to avoid the production of antibodies against meiotic and postmeiotic germ cells. Studies have demonstrated that some unlikely partners, namely adhesion protein complexes (e.g., occludin-ZO-1, N-cadherin-β-catenin, claudin-5-ZO-1), steroids (e.g., testosterone, estradiol-17β), nonreceptor protein kinases (e.g., focal adhesion kinase, c-Src, c-Yes), polarity proteins (e.g., PAR6, Cdc42, 14-3-3), endocytic vesicle proteins (e.g., clathrin, caveolin, dynamin 2), and actin regulatory proteins (e.g., Eps8, Arp2/3 complex), are working together, apparently under the overall influence of cytokines (e.g., transforming growth factor-β3, tumor necrosis factor-α, interleukin-1α). In short, a “new” BTB is created behind spermatocytes in transit while the “old” BTB above transiting cells undergoes timely degeneration, so that the immunological barrier can be maintained while spermatocytes are traversing the BTB. We also discuss recent findings regarding the molecular mechanisms by which environmental toxicants (e.g., cadmium, bisphenol A) induce testicular injury via their initial actions at the BTB to

  4. [Red Blood Cells Raman Spectroscopy Comparison of Type Two Diabetes Patients and Rats].

    PubMed

    Wang, Lei; Liu, Gui-dong; Mu, Xin; Xiao, Hong-bin; Qi, Chao; Zhang, Si-qi; Niu Wen-ying; Jiang, Guang-kun; Feng, Yue-nan; Bian, Jing-qi

    2015-10-01

    By using confocal Raman spectroscopy, Raman spectra were measured in normal rat red blood cells, normal human red blood cells, STZ induced diabetetic rats red blood cells, Alloxan induced diabetetic rats red blood cells and human type 2 diabetes red blood cells. Then principal component analysis (PCA) with support vector machine (SVM) classifier was used for data analysis, and then the distance between classes was used to judge the degree of close to two kinds of rat model with type 2 diabetes. The results found significant differences in the Raman spectra of red blood cell in diabetic and normal red blood cells. To diabetic red blood cells, the peak in the amide VI C=O deformation vibration band is obvious, and amide V N-H deformation vibration band spectral lines appear deviation. Belong to phospholipid fatty acyl C-C skeleton, the 1 130 cm(-1) spectral line is enhanced and the 1 088 cm(-1) spectral line is abated, which show diabetes red cell membrane permeability increased. Raman spectra of PCA combined with SVM can well separate 5 types of red blood cells. Classifier test results show that the classification accuracy is up to 100%. Through the class distance between the two induced method and human type 2 diabetes, it is found that STZ induced model is more close to human type 2 diabetes. In conclusion, Raman spectroscopy can be used for diagnosis of diabetes and rats STZ induced diabetes method is closer to human type 2 diabetes. PMID:26904817

  5. Leptin transport across the blood-brain barrier: implications for the cause and treatment of obesity.

    PubMed

    Banks, W A

    2001-01-01

    Leptin has emerged as a major regulator of adiposity. Leptin is released into the blood from fat cells and circulates to the brain where it crosses the blood-brain barrier (BBB) to act at receptors within the central nervous system to affect appetite, thermogenesis, and a number of other actions. In humans and in many rodent models, resistance to leptin appears to be a chief cause of obesity. Determining the cause of leptin resistance is fundamental to developing strategies for the use of leptin in obesity. The literature characterizing the transport of leptin across the BBB is reviewed. This literature strongly suggests that the cause of leptin resistance is due a decreased transport of leptin across the BBB in obese humans and rodents. The main cause of this resistance appears to be an impairment in the activity of the transporter rather than just simply saturation at higher doses. Strategies to overcome impaired BBB transport are reviewed, including the use of allosteric regulators and the delivery of material by the intrathecal route. PMID:11172704

  6. Implications of Big Data for cell biology

    PubMed Central

    Dolinski, Kara; Troyanskaya, Olga G.

    2015-01-01

    “Big Data” has surpassed “systems biology” and “omics” as the hottest buzzword in the biological sciences, but is there any substance behind the hype? Certainly, we have learned about various aspects of cell and molecular biology from the many individual high-throughput data sets that have been published in the past 15–20 years. These data, although useful as individual data sets, can provide much more knowledge when interrogated with Big Data approaches, such as applying integrative methods that leverage the heterogeneous data compendia in their entirety. Here we discuss the benefits and challenges of such Big Data approaches in biology and how cell and molecular biologists can best take advantage of them. PMID:26174066

  7. Intercellular transfer of P-glycoprotein in human blood-brain barrier endothelial cells is increased by histone deacetylase inhibitors.

    PubMed

    Noack, Andreas; Noack, Sandra; Buettner, Manuela; Naim, Hassan Y; Löscher, Wolfgang

    2016-01-01

    The blood-brain barrier (BBB) controls the entry of compounds into the brain, thereby regulating brain homeostasis. Efflux transporters such as P-glycoprotein (Pgp) significantly contribute to BBB function. Multiple signaling pathways modulate the expression and activity of Pgp in response to xenobiotics and disease. A non-genetic way of intercellular transfer of Pgp occurs in cancer cells, but whether this also occurs in non-cancer cells such as endothelial cells that form the BBB is not known. A human brain endothelial cell line (hCMEC/D3) was used to study whether cell-to-cell Pgp transfer occurs during co-culturing with Pgp-EGFP expressing hCMEC/D3 cells. The Pgp-EGFP fusion protein was transferred from donor to recipient cells by cell-to-cell contact and Pgp-EGFP enriched vesicles, which were exocytosed by donor cells and endocytosed by adherent recipient cells. Flow cytometry experiments with the Pgp substrate eFLUXX-ID Gold demonstrated that the transferred Pgp is functional in the recipient cells. Exposure of the donor cells with inhibitors of histone deacetylases (HDACs) resulted in an enhanced intercellular Pgp transfer. Non-genetic transfer of a resistance phenotype and its regulation by HDACs is a novel mechanism of altering BBB functionality. This mechanism may have important implications for understanding drug-induced alterations in Pgp expression and activity. PMID:27375084

  8. Mammalian Cell Competitions, Cell-in-Cell Phenomena and Their Biomedical Implications.

    PubMed

    Huang, H; Chen, Z; Sun, Q

    2015-01-01

    Cell competition was first identified four decades ago as a mechanism to eliminate less fit cells during development in Drosophila melanogaster, and later postulated to be involved in tumorigenesis of human beings. However, evidence for a similar mechanism functional in mammals and tumors was missed until recent years. Like cell competition in fly, multiple forms of competition mechanisms were reported in mammalian system, and some of them were found participating in tumor initiation. Lately, entosis, a mechanism of cell cannibalisms responsible for the formation of cell-in-cell structures in human tumors, was identified as a novel member of ever-expanding family of mammalian cell competitions (MaCCs), and proposed to be able to promote clonal selection and tumor evolution. Thus, engulfment by neighboring cells other than the professional phagocytes, an issue still in debate in fly, was clearly demonstrated in mammals to be responsible for loser elimination. Competition mediated by cell-in-cell structures, formed by multiple cannibal mechanisms, constitutes a novel class of MaCCs. This review will summarize current research on mammalian cell competitions, followed by feature and mechanism analysis and their potential implications in the pathology and treatment of human tumors. PMID:26511708

  9. Effect of polyclonal activators on cytokine production by blood cells and by malignant breast cancer cells.

    PubMed

    Kunts, T A; Karpukhina, K V; Mikhaylova, E S; Marinkin, I O; Varaksin, N A; Autenshlyus, A I; Lyakhovich, V V

    2016-01-01

    The production of cytokines by peripheral blood cells and biopsy specimens of tumors stimulated by polyclonal activators (PAs) was evaluated in 34 patients with invasive ductal breast carcinoma using enzyme-linked immunosorbent assay (ELISA). Positive correlation between the stimulation index of polyclonal activators (SIPA) for IL-18 production by the tumor and the relative content of poorly differentiated cells was revealed. The latter, in turn, was positively correlated with the numbers of normal and pathologic mitoses and the degree of malignancy. Cancer cells can produce IL-18, which is involved in the process of angiogenesis, stimulates invasion and metastasis. Decrease in SIPA for the production of IL-6 and GCSF by peripheral blood cells could serve as an indicator of malignant progression in invasive ductal breast carcinoma. PMID:27021370

  10. Measurement of interaction forces between red blood cells in aggregates by optical tweezers

    SciTech Connect

    Maklygin, A Yu; Priezzhev, A V; Karmenian, A; Nikitin, Sergei Yu; Obolenskii, I S; Lugovtsov, Andrei E; Kisun Li

    2012-06-30

    We have fabricated double-beam optical tweezers and demonstrated the possibility of their use for measuring the interaction forces between red blood cells (erythrocytes). It has been established experimentally that prolonged trapping of red blood cells in a tightly focused laser beam does not cause any visible changes in their shape or size. We have measured the interaction between red blood cells in the aggregate, deformed by optical tweezers.

  11. Red blood cells do not contribute to removal of K+ released from exhaustively working forearm muscle.

    PubMed

    Maassen, N; Foerster, M; Mairbäurl, H

    1998-07-01

    K+ released from exercising muscle via K+ channels needs to be removed from the interstitium into the blood to maintain high muscle cell membrane potential and allow normal muscle contractility. Uptake by red blood cells has been discussed as one mechanism that would also serve to regulate red blood cell volume, which was found to be constant despite increased plasma osmolality and K+ concentration ([K+pl]). We evaluated exercise-related changes in [K+pl], pH, osmolality, mean cellular Hb concentration, cell water, and red blood cell K+ concentration during exhaustive handgrip exercise. Unidirectional 86Rb+ (K+) uptake by red blood cells was measured in media with elevated extracellular K+, osmolarity, and catecholamines to simulate particularly those exercise-related changes in plasma composition that are known to stimulate K+ uptake. During exercise [K+pl] increased from 4.4 +/- 0.7 to 7.1 +/- 0.5 mmol/l plasma water and red blood cell K+ concentration increased from 137.2 +/- 6.0 to 144.6 +/- 4.6 mmol/l cell water (P blood cells was increased by approximately 20% on stimulation, caused by activation of the Na+-K+ pump and Na+-K+-2Cl- cotransport. Results indicate the K+ content of red blood cells did not change as cells passed the exhaustively exercising forearm muscle despite the elevated [K+pl]. The tendency for an increase in intracellular K+ concentration was due to a slight, although statistically not significant, decrease in red blood cell volume. K+ uptake, although elevated, was too small to move significant amounts of K+ into red blood cells. Our results suggest that red blood cells do not contribute to the removal of K+ released from muscle and do not regulate their volume by K+ uptake during exhaustive forearm exercise. PMID:9655793

  12. Effect of 4-hydroxypyrazolo (3,4-D) pyrimidine (allopurinol) on post-irradiation cerebral blood flow: implications of free-radical involvement

    SciTech Connect

    Cockerham, L.G.; Arroyo, C.M.; Hampton, J.D.

    1988-01-01

    Early transient incapacitation (ETI) is the complete cessation of motor performance, occurring transiently and within the first 30 min following exposure to supralethal doses of ionizing irradiation. Studies have reported severe decreases in regional cerebral blood flow (rCBF) in primates at the same postirradiation time after receiving supralethal doses of gamma irradiation. One study demonstrated a dramatic fall of total cerebral blood flow following a single, 25-Gy, Co exposure. Free radical interactions have been implicated in a large number of pathological conditions including irradiation injury, ischemia, microvascular injury, and cell membrane damage. The triphasic cerebral ischemic response seen after irradiation may be even more damaging than complete ischemia since reperfusion may lead to the formation of additional free radicals. A possible mode of pharmacologic intervention may be the introduction of superoxide dismutase or allopurinol since both were used to attenuate the biochemical and functional damage usually associated with free-radical production. This study was designed to determine whether the inhibition of free radical formation via the preirradiation administration of allopurinol would be successful in altering the postirradiation hypotension and reduced rCBF. The hippocampus and the hypothalamus, were selected for the determination of blood flow in this study since a dramatic, postirradiation decrease in blood flow has been reported in these areas.

  13. Compensation of CD55 Underexpression on Red Blood Cells of β-Thalassemia Major Patients.

    PubMed

    Obaid, Jamil M A S; Abo El-Nazar, Salma Y; Ghanem, Amal M; El-Hadidi, Abeer S; Mersal, Basma H M

    2015-01-01

    β-Thalassemia (β-thal), is an autosomal recessive disorder caused by mutations at the β gene locus. β-Thalassemia major (β-TM) is a severe form of the disease, characterized by severe hypochromic and hemolytic anemia with an increased need for transfusion. Hemolysis is caused by intoxication, whereas mechanical removal of the affected cells caused by macrophage. Immunological implications are also reported and occur via antibodies and complement. We found previously that complement inhibitor receptor CD55 is underexpressed in these patients. This study concerns the compensatory mechanisms of this diminished expression upon flow cytometry analysis of CD55 and CD59 on the red blood cells (RBCs) of β-thal patients. This study was conducted on 24 patients and 10 healthy controls. Full history and transfusion data was obtained, then a complete blood count (CBC) and flow cytometry analysis of CD55 and CD59 on erythrocytes were carried out. Within our 24 patients, we found a diminished expression of CD55 with a normal expression of CD59. The percentage of cells that express CD55 was significantly different from that of the controls. The mean fluorescence intensity (MFI) of CD55 and CD59 with correlation studies reveals that different factors affect the underexpression of CD55 and also revealed compensatory changes of the defect to minimize the hemolysis occurring in β-thal patients. Compensation of CD55 underexpression in the deficient patients occurred when an increase in the MFI of both the receptor CD55, on the positive cells, and another complement inhibitor receptor CD59. PMID:25897480

  14. Electrophoretic characterization of aldehyde-fixed red blood cells, kidney cells, lynphocytes and chamber coatings

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Ground-based electrokinetic data on the electrophoresis flight experiment to be flown on the Apollo-Soyuz Test Project experiment MA-011 are stipulated. Aldehyde-fixed red blood cells, embryonic kidney cells and lymphocytes were evaluated by analytical particle electrophoresis. The results which aided in the interpretation of the final analysis of the MA-011 experiment are documented. The electrophoresis chamber surface modifications, the buffer, and the material used in the column system are also discussed.

  15. Mitogen-activated Tasmanian devil blood mononuclear cells kill devil facial tumour disease cells.

    PubMed

    Brown, Gabriella K; Tovar, Cesar; Cooray, Anne A; Kreiss, Alexandre; Darby, Jocelyn; Murphy, James M; Corcoran, Lynn M; Bettiol, Silvana S; Lyons, A Bruce; Woods, Gregory M

    2016-08-01

    Devil facial tumour disease (DFTD) is a transmissible cancer that has brought the host species, the Tasmanian devil, to the brink of extinction. The cancer cells avoid allogeneic immune recognition by downregulating cell surface major histocompatibility complex (MHC) I expression. This should prevent CD8(+) T cell, but not natural killer (NK) cell, cytotoxicity. The reason why NK cells, normally reactive to MHC-negative cells, are not activated to kill DFTD cells has not been determined. The immune response of wild devils to DFTD, if it occurs, is uncharacterised. To investigate this, we tested 12 wild devils with DFTD, and found suggestive evidence of low levels of antibodies against DFTD cells in one devil. Eight of these devils were also analysed for cytotoxicity, however, none showed evidence for cytotoxicity against cultured DFTD cells. To establish whether mimicking activation of antitumour responses could induce cytotoxic activity against DFTD, Tasmanian devil peripheral blood mononuclear cells (PBMCs) were treated with either the mitogen Concanavalin A, the Toll-like receptor agonist polyinosinic:polycytidylic acid or recombinant Tasmanian devil IL-2. All induced the PBMC cells to kill cultured DFTD cells, suggesting that activation does not occur after encounter with DFTD cells in vivo, but can be induced. The identification of agents that activate cytotoxicity against DFTD target cells is critical for developing strategies to protect against DFTD. Such agents could function as adjuvants to induce functional immune responses capable of targeting DFTD cells and tumours in vivo. PMID:27089941

  16. Prevalence and classification of anemia in elective orthopedic surgery patients: implications for blood conservation programs.

    PubMed

    Goodnough, L T; Vizmeg, K; Sobecks, R; Schwarz, A; Soegiarso, W

    1992-01-01

    We audited 281 consecutive orthopedic patients scheduled for surgery for whom blood type/cross-matching was requested over a 6-month period. One hundred and sixty-two patients predonated autologous blood at University Hospitals of Cleveland, and 34 (21%) of these were anemic [hematocrit (Hct) less than or equal to 39%] at initial donation. Twelve (35%) of these 34 anemic autologous blood donors subsequently received homologous blood. In contrast, 18 (15%) of 128 nonanemic autologous blood donors received homologous blood (p = 0.05). In 119 patients who did not donate autologous blood, 39 (33%) were anemic at admission. Of these, 22 (56%) received homologous blood. In the 80 remaining nonanemic patients, 33 (41%) received homologous blood (p = 0.119). Analysis of discharge Hct indicates that 31 (12%) of 263 evaluable patients were possibly transfused inappropriately. The anemias of a cohort of 30 autologous donors were analyzed: 5 had rheumatoid arthritis without iron deficiency. Nine (30%) others had evidence of iron deficiency. Sixteen (53%) had an unclassified anemia of chronic disease. We conclude: (1) the high rates of homologous blood exposure indicate a need for innovative blood conservation strategies in anemic autologous blood donors; (2) the prevalence of anemia and the high rates of homologous blood exposure in anemic patients who did not donate autologous blood demonstrate a need for early recognition and treatment in order to procure autologous blood and reduce homologous blood exposure; (3) the presence of inappropriate autologous and homologous transfusions demonstrates a need for more effective physician education programs that emphasize 'no blood transfusion' as an alternative to enhance blood conservation effectiveness. PMID:1441312

  17. Red blood cell transfusion strategies and Maximum surgical blood ordering schedule

    PubMed Central

    Iyer, Shivakumar S; Shah, Jignesh

    2014-01-01

    Blood transfusion is one of the practices that is in vogue because it expands blood volume and purportedly improves the oxygen carrying capacity. Despite this supposed physiological benefit, paradoxically, both anaemia and transfusion are independently associated with organ injury and increased morbidity. Historically, transfusion was used to maintain blood haemoglobin concentration above 10 g/dL and a haematocrit above 30%. There is now a greater emphasis on interventions to reduce the use of transfusion as it is a scarce and expensive resource with many serious adverse effects. Institutional maximum surgical blood ordering schedule algorithm developed with data analysis and consensus of surgeons, anaesthesiologists and blood banks can reduce the overuse of blood. A PubMed search was performed with search words/combination of words ‘erythrocyte transfusion, adverse effects, economics, mortality, therapy, therapeutic use and utilisation’. Search yielded a total of 1541 articles that were screened for clinical relevance for the purpose of this review. PMID:25535420

  18. Mimicking the Interfacial Dynamics of Flowing White Blood Cells

    NASA Astrophysics Data System (ADS)

    Santore, Maria

    2015-03-01

    The rolling of particles on surfaces, facilitated by hydrodynamic forces combined with localized surface interactions of the appropriate strengths, spatial arrangements, and ranges, is a technologically useful means of transporting and manipulating particles. One's intuition for the rolling of a marble or a car tire cannot be extrapolated down to microparticle length scales because the microparticle interactions are dominated by electrostatic, van der Waals, and hydrogen bonding interactions rather than a friction that depends on an imposed normal force. Indeed, our microparticle rolling systems are inspired by the rolling of white blood cells on the inner walls of venules as part of the innate immune response: Selectin molecules engage with their counterparts on the opposing surfaces to slow cell motion relative to that for freely flowing cells. In the resulting rolling signature, ligand-receptor binding and crack closing on the front of the cell are balanced with molecular dis-bonding and crack opening at the rear. The contact region is relatively static, allowing other interactions (for instance signaling) to occur for a finite duration. Thus, achieving particle rolling in synthetic systems is important because it facilitates particle-surface interactions in a continuous nonfouling fashion where the contact surface is continually renewed. In developing a synthetic model for this system, we employ polymers to modify flowing particles and /or planar collectors, producing heterogeneous interfaces which can support rolling or produce other motion signatures such as skipping, arrest, or free flow. We identify, in the synthetic system, combinations of variables that produce rolling and demonstrate how the distinction between rolling and arrest is not a simple matter of the adhesion strength between the particles and the collector. Rolling is a cooperative process and the coordination of binding in one location with dis-bonding in another requires appropriate length

  19. Targeted erythropoietin selectively stimulates red blood cell expansion in vivo.

    PubMed

    Burrill, Devin R; Vernet, Andyna; Collins, James J; Silver, Pamela A; Way, Jeffrey C

    2016-05-10

    The design of cell-targeted protein therapeutics can be informed by natural protein-protein interactions that use cooperative physical contacts to achieve cell type specificity. Here we applied this approach in vivo to the anemia drug erythropoietin (EPO), to direct its activity to EPO receptors (EPO-Rs) on red blood cell (RBC) precursors and prevent interaction with EPO-Rs on nonerythroid cells, such as platelets. Our engineered EPO molecule was mutated to weaken its affinity for EPO-R, but its avidity for RBC precursors was rescued via tethering to an antibody fragment that specifically binds the human RBC marker glycophorin A (huGYPA). We systematically tested the impact of these engineering steps on in vivo markers of efficacy, side effects, and pharmacokinetics. huGYPA transgenic mice dosed with targeted EPO exhibited elevated RBC levels, with only minimal platelet effects. This in vivo selectivity depended on the weakening EPO mutation, fusion to the RBC-specific antibody, and expression of huGYPA. The terminal plasma half-life of targeted EPO was ∼28.3 h in transgenic mice vs. ∼15.5 h in nontransgenic mice, indicating that huGYPA on mature RBCs acted as a significant drug sink but did not inhibit efficacy. In a therapeutic context, our targeting approach may allow higher restorative doses of EPO without platelet-mediated side effects, and also may improve drug pharmacokinetics. These results demonstrate how rational drug design can improve in vivo specificity, with potential application to diverse protein therapeutics. PMID:27114509

  20. Dynamic morphology and cytoskeletal protein changes during spontaneous inside-out vesiculation of red blood cell membranes.

    PubMed

    Tiffert, Teresa; Lew, Virgilio L

    2014-12-01

    Vesicle preparations from cell plasma membranes, red blood cells in particular, are extensively used in transport and enzymic studies and in the fields of drug delivery and drug-transport interactions. Here we investigated the role of spectrin-actin, the main components of the red cell cortical cytoskeleton, in a particular mechanism of vesicle generation found to be relevant to the egress process of Plasmodium falciparum merozoites from infected red blood cells. Plasma membranes from red blood cells lysed in ice-cold media of low ionic strength and free of divalent cations spontaneously and rapidly vesiculate upon incubation at 37 °C rendering high yields of inside-out vesicles. We tested the working hypothesis that the dynamic shape transformations resulted from changes in spectrin-actin configuration within a disintegrating cytoskeletal mesh. We showed that cytoskeletal-free membranes behave like a two-dimensional fluid lacking shape control, that spectrin-actin remain attached to vesiculating membranes for as long as spontaneous movement persists, that most of the spectrin-actin detachment occurs terminally at the time of vesicle sealing and that naked membrane patches increasingly appear during vesiculation. These results support the proposed role of spectrin-actin in spontaneous vesiculation. The implications of these results to membrane dynamics and to the mechanism of merozoite egress are discussed. PMID:24615169