Rapid computation of photoacoustic fields from normal and pathological red blood cells using a Green's function method

Novel single-cell functional analysis of red blood cells using laser tweezers Raman spectroscopy: Application for sickle cell disease

We have developed a new intracavity laser technique that uses living or fixed cells at integral components of a laser. The cells are placed on an AlGaAs/GaAs surface-emitting semiconductor wafer and covered with a glass dielectric mirror to form a laser resonator. In this arrangement, the cells serve as optical waveguides (or lens elements) to confine (or focus) light generated in the resonator by the semiconductor. Because of the high transparency, the cells aid the lasing process to generate laser light. This ultra sensitive laser provides a novel imaging/spectroscopic technique for histologic examination which we demonstrate with normal and sickled human red blood cells. Extremely high contrast microscopic images of the cells are observed near 830-850 nm. These images correspond to electromagnetic modes of cell structures and are sensitive to shape of the cell. Using a high resolution spectrometer, we resolve the light emitted from these images into very narrow spectral peaks associated with the lasing modes. Analysis of the spectra reveals that the distribution of peaks is quite different for normal and sickled red blood cells. This technique, in a more developed form, may be useful for the rapid analysis of these and other kinds of normal and abnormal cells.

Sodium transport in red cells of patients with acute viral hepatitis

Counting morphologically normal cells in human red blood cells (RBCs) is extremely beneficial in the health care field. We propose a three-dimensional (3-D) classification method of automatically determining the morphologically normal RBCs in the phase image of multiple human RBCs that are obtained by off-axis digital holographic microscopy (DHM). The RBC holograms are first recorded by DHM, and then the phase images of multiple RBCs are reconstructed by a computational numerical algorithm. To design the classifier, the three typical RBC shapes, which are stomatocyte, discocyte, and echinocyte, are used for training and testing. Nonmain or abnormal RBC shapes different from the three normal shapes are defined as the fourth category. Ten features, including projected surface area, average phase value, mean corpuscular hemoglobin, perimeter, mean corpuscular hemoglobin surface density, circularity, mean phase of center part, sphericity coefficient, elongation, and pallor, are extracted from each RBC after segmenting the reconstructed phase images by using a watershed transform algorithm. Moreover, four additional properties, such as projected surface area, perimeter, average phase value, and elongation, are measured from the inner part of each cell, which can give significant information beyond the previous 10 features for the separation of the RBC groups; these are verified in the experiment by the statistical method of Hotelling's T-quare test. We also apply the principal component analysis algorithm to reduce the dimension number of variables and establish the Gaussian mixture densities using the projected data with the first eight principal components. Consequently, the Gaussian mixtures are used to design the discriminant functions based on Bayesian decision theory. To improve the performance of the Bayes classifier and the accuracy of estimation of its error rate, the leaving-one-out technique is applied. Experimental results show that the proposed method can yield good results for calculating the percentage of each typical normal RBC shape in a reconstructed phase image of multiple RBCs that will be favorable to the analysis of RBC-related diseases. In addition, we show that the discrimination performance for the counting of normal shapes of RBCs can be improved by using 3-D features of an RBC.

This paper presents the response of different type of Red Blood cells to an applied electric pulse. Different electroporation parameters are presented based on a mathematical model that uses the whole membrane of normal and malignant red blood cells. Different parameters can be extracted from the analysis of the electroporation of a biological cell, such as the deformation rate of its membrane and its electroporation response. This paper focuses on two main features to differ between the normal and malignant red blood cells. These features are the membrane potential and the density of the pores as a response for an applied electric field. Also, this paper presents a COMSOL Model which is used to solve both the membrans’s transmembrane potential and the distribution of the pores across it.

Nucleated red blood cell count in the differentiation of fetuses with pathologic growth restriction from healthy small-for-gestational-age fetuses

The Role of Lactadherin in the Phagocytosis of Phosphatidylserine-Expressing Sickle Red Blood Cell by Macrophages.

Sickle cell anemia (SCA) is a type of haemolytic anemia which is the most commonly inherited blood disorder. Detection of red blood cell and sickle cell from sickle cell anemic person is a very challenging task. Besides traditional visual inspection of microscopic images, various methods have been developed which are based on image processing technique for faster and more accurate diagnosis of SCA. In this paper normal and abnormal red blood cells have been detected using Niblack's thresholding technique from microscopic blood images of sickle cell anemic patient. The process involves preprocessing of microscopic blood smear and segmenting the preprocessed image using Niblack's thresholding algorithm. Then using geometrical features of blood cells a metric (form factor) is calculated to classify normal red blood cells and abnormal cells.

The complement system uses a complex set of cell-bound and plasma regulators to protect host cells from complement-mediated cytolysis. Although PNH red blood cells (RBCs) are partially (type II) or completely (type III) deficient in GPI-linked complement regulatory molecules CD59 and CD55, they are not rapidly lysed by complement. For instance, the in vivo lifespan of PNH III RBCs is 6–60 days, and is close to that of normal cells for PNH II RBCs. The plasma regulator factor H (fH) plays a key role in complement homeostasis. Here we show that a recombinant protein consisting of its two C-terminal domains (rH19-20) blocks its cell surface complement regulatory functions without affecting fluid phase control of soluble C3b. Also, addition of rH19-20 to normal human serum leads to moderate complement-mediated lysis of normal human RBCs, which possess membrane-bound complement regulators, and to aggressive lysis of PNH II and III cells. In agreement with this, the inhibition of CD59 or CD55 on normal RBCs results in their aggressive lysis only when combined with the loss of fH cell surface control. Taken together, the results highlight the importance of the cell surface protective functions of fH compared to other complement regulatory proteins and indicate that fH is essential for the 6–60 day survival of PNH RBCs, with possible implications in diagnosis and treatment. Research support NIH DK35081.

Morphology of Normal Erythrocyte and Acanthocyte Using Nomarski Optics and the Scanning Electron Microscope

Red blood cell size is important for adherence of blood platelets to artery subendothelium

Sensitive Detection of Survival of Paroxysmal Nocturnal Hemoglobinuria (PNH) Clones in Red Blood Cells, Granulocytes and Monocytes by High Resolution Multiparameter Flow Cytometry.

Dear Sir, Transfusion therapy is a cornerstone in the treatment of sickle cell anaemia as it improves tissue oxygenation (by increasing the absolute value of haemoglobin and reducing the proportion of haemoglobin S) as well as reducing blood viscosity; chronic transfusion therapy also leads to the suppression of the propensity of endogenous red blood cells to sickle1. The transfusion therapy is based mainly on red blood cell transfusions while experience with the use of erythrocyte exchange (EEX) in this disease is limited2,3. EEX, practised both as acute therapy and as periodic and scheduled treatment, is an “exchange of red blood cells” designed to remove large volumes of sickle cells quickly and replace them with normal red blood cells, without increasing blood viscosity or causing iron overload. The aim of EEX is to reduce and maintain the haemoglobin S <30%, while bringing the values of haemoglobin to approximately 10 g/dL (haematocrit <30%). Acute EEX is considered the treatment of choice in cases in which there is an indication for transfusion therapy but the levels of haemoglobin are ≥10 g/dL, especially in the treatment of stroke3. On the other hand, the purpose of periodic, programmed EEX is to maintain the values of haemoglobin S stably below 30–35%, avoiding iron overload, reducing accesses to hospital and thereby improving the quality of life of patients1. At the Blood Transfusion Service of St. Anna Hospital in Ferrara, we use EEX in the chronic treatment of patients with homozygous sickle cell disease. So far we have followed ten patients (4 males and 6 females), four of whom are children. Most of the patients are African or Albanian. In the period between 2003 to 2013 we performed over 350 EEX procedures, which were carried out in 60–90 minutes with a continuous flow cell separator (Fresenius Kabi AG, Bad Homburg, Germany -COM.TEC®). The red blood cells used for the exchange were leucodepleted, extensively typed (for Rh, Kell, Jk, Fy) and resuspended in SAG-M preservative solution (maximum 5–7 days of storage) with a haematocrit of about 60%. The erythrocyte volume exchanged in each procedure was calculated using a modified method studied at our Transfusion Service to obtain greater removal of haemoglobin S. This method involves three steps carried out with the plasma exchange device of the cell separator. Step 1 - Consisted of connecting, on the cell separator, the reinfusion line of red blood cells with the bag of the waste and removing a volume of patient’s red blood cells calculated to reduce the haematocrit by 10–15%, using saline or human albumin solutions at 4% as replacement fluid. Step 2 - Was isovolaemic exchange of patient’s red blood cells with an equal volume of homologous erythrocytes (20 mL of red blood cells/kg weight). Step 3 - Was to restore the connection of the reinfusion line of red blood cells with the patient and restore the haematocrit to the desired value by by exchanging a volume of the patient’s plasma with the appropriate volume of homologous red blood cells. Compared to standard red cell exchange, the use of this procedure allows a greater percentage reduction of haemoglobin S (60% instead of 50%) using a smaller volume of homologous red blood cells (20 mL red blood cells/kg weight instead of 30 mL/kg weight). Pre-exchange haemoglobin S levels (evaluated after 55–60 days) were always under 50–52%. The procedures were well tolerated and there were no adverse reactions; isovolaemic EEX also safeguarded our patients from the iron overload that can follow transfusion therapy. Only one patient had an episode of erythrocyte alloimmunisation, with anti-M antibody specificity. From a clinical point of view, all the patients treated with this novel EEX are in durable symptomatic remission and none has dangerous complications of their disease. EEX is still a little-known procedure used in the acute or long-term treatment of sickle cell disease2. Our experience leads us to believe, partly in view of the increasing number of citizens of different ethnic groups (including those with high incidences of sickle cell disease) that live in our country3, that EEX should be taken into account for the management of these patients, because of its high tolerability and effective reduction and control of haemoglobin S levels (with excellent control of symptoms and complications) without iron overload. Furthermore, the increased removal of haemoglobin S with the three-step procedure not only saves homologous red blood cells, but could also provide longer periods of therapeutic efficacy thereby reducing accesses to hospital and improving the patients’ quality of life.

To investigate the differences of metabolic pathways of leucocyte-deplated RBCs prepared by using lipid whole blood and nomal blood during routine storage so as to provide some reference for clinical blood use. Twenty U whole blood from 20 donors, including 10 U lipid blood and 10 U normal whole blood, were selected for preparing leukodepleted red blood cells, red blood cells were taken from storage bags on day 0, 14 and 35, respectively. Metabolites in the red blood cells were analyzed, red blood cell metabolic extracts were detected by UPLC-MS/MS. The metabolite data of RBC from 2 groups were analyzed by SIMCA-P 13.0 software using OPLS-DA and by SPSS 19.0 using Mann-Whitney U test. Difference of metabolic pathways was described according to different metabolites. The glucose, adenine, pyruvic acid, GSH, GSSG and niacinamide levels on day 0 in lipid RBCs were higher than those in the control group(P<0.05). The glucose, pyruvic acid and GSH levels on day 14 in lipid RBCs were lower than those in the control group (P<0.05), and the levels of adenine, GSSG and niacinamide were higher than that in the control group (P<0.05). The glucose level on day 0 was lower than that in the control group (P<0.05), and the levels of adenine and niacinamide were higher than those in the control group (P<0.05). but the pyruvic acid, GSH and GSSG levels were not significantly different between 2 groups (P>0.05). Compared with the normal red blood cells, the energy metabolism pathway decreases in lipid red blood cells within the storage period and pentose phosphate pathway increases.

Hydroxyurea Treatment of Children with Sickle Cell Disease Inhibits RBC Membrane Degradation by Secretory Phospholipase a2.