Deep ensemble learning enables highly accurate classification of stored red blood cell morphology.

Changes in red blood cell (RBC) morphology distribution have emerged as a quantitative biomarker for the degradation of RBC functional properties during hypothermic storage. Previously published automated methods for classifying the morphology of stored RBCs often had insufficient accuracy and relied on proprietary code and datasets, making them difficult to use in many research and clinical applications. Here we describe the development and validation of a highly accurate open-source RBC morphology classification pipeline based on ensemble deep learning (DL).

Microfluidic capillary networks are more sensitive than ektacytometry to the decline of red blood cell deformability induced by storage.

Ektacytometry has been the primary method for evaluating deformability of red blood cells (RBCs) in both research and clinical settings. This study was designed to test the hypothesis that the flow of RBCs through a network of microfluidic capillaries could provide a more sensitive assessment of the progressive impairment of RBC deformability during hypothermic storage than ektacytometry. RBC units (n = 9) were split in half, with one half stored under standard (normoxic) conditions and the other half stored hypoxically, for up to 6 weeks.

Centrifugation-free washing: A novel approach for removing immunoglobulin A from stored red blood cells.

Washed red blood cells (RBCs) are indicated for immunoglobulin A (IgA) deficient recipients. Centrifugation-based cell processors commonly used by hospital blood banks cannot consistently reduce IgA below the recommended levels, hence double washing is frequently required. Here, we describe a prototype of a simple, portable, disposable system capable of washing stored RBCs without centrifugation, while reducing IgA below 0.

Substituting Sodium Hydrosulfite with Sodium Metabisulfite Improves Long-Term Stability of a Distributable Paper-Based Test Kit for Point-of-Care Screening for Sickle Cell Anemia.

Sickle cell anemia (SCA) is a genetic blood disorder that is particularly lethal in early childhood. Universal newborn screening programs and subsequent early treatment are known to drastically reduce under-five SCA mortality. However, in resource-limited settings, cost and infrastructure constraints limit the effectiveness of laboratory-based SCA screening programs.

Influence of feeding hematocrit and perfusion pressure on hematocrit reduction (Fåhraeus effect) in an artificial microvascular network.

Objective: Hct in narrow vessels is reduced due to concentration of fast-flowing RBCs in the center, and of slower flowing plasma along the wall of the vessel, which in combination with plasma skimming at bifurcations leads to the striking heterogeneity of local Hct in branching capillary networks known as the network Fåhraeus effect. We analyzed the influence of feeding Hct and perfusion pressure on the Fåhraeus effect in an AMVN.

Methods: RBC suspensions in plasma with Hcts between 20% and 70% were perfused at pressures of 5-60 cm H O through the AMVN.

Washing in hypotonic saline reduces the fraction of irreversibly-damaged cells in stored blood: a proof-of-concept study.

Background: During hypothermic storage, a substantial fraction of red blood cells (RBCs) transforms from flexible discocytes to rigid sphero-echinocytes and spherocytes. Infusion of these irreversibly-damaged cells into the recipient during transfusion serves no therapeutic purpose and may contribute to adverse outcomes in some patients. In this proof-of-concept study we describe the use of hypotonic washing for selective removal of the irreversibly-damaged cells from stored blood.

Optimal hematocrit in an artificial microvascular network.

Background: Higher hematocrit increases the oxygen-carrying capacity of blood but also increases blood viscosity, thus decreasing blood flow through the microvasculature and reducing the oxygen delivery to tissues. Therefore, an optimal value of hematocrit that maximizes tissue oxygenation must exist.

Study Design And Methods: We used viscometry and an artificial microvascular network device to determine the optimal hematocrit in vitro.

Traveling to Angola to Validate a Paper-Based Sickle Cell Disease Test.

When I started graduate school, I had no idea that it would take me halfway around the world to a small clinic in Cabinda, Angola, but I'm glad that it did. Since 2011, I have been a part of the team of engineers and clinicians, led by Dr. Sergey Shevkoplyas, working to develop a simple, low-cost, paper-based test for sickle cell disease-a common inherited blood disorder that is most prevalent in sub-Saharan Africa (Figure S1).

Paper-Based Diagnostics: Rethinking Conventional Sickle Cell Screening to Improve Access to High-Quality Health Care in Resource-Limited Settings.

Every year, hundreds of thousands of children worldwide are born with sickle cell disease, a genetic disorder that impacts the hemoglobin molecules in blood. If left undiagnosed and untreated, most affected children will die before reaching the age of five. However, highly accurate diagnostic methods and effective treatment regimens for sickle cell disease have been known for many years, and children who receive early diagnosis and subsequent comprehensive care survive well into adulthood-as evidenced by the tremendous success of universal newborn screening programs in North America and Europe.

A Paper-Based Test for Screening Newborns for Sickle Cell Disease.

The high cost, complexity and reliance on electricity, specialized equipment and supplies associated with conventional diagnostic methods limit the scope and sustainability of newborn screening for sickle cell disease (SCD) in sub-Saharan Africa and other resource-limited areas worldwide. Here we describe the development of a simple, low-cost, rapid, equipment- and electricity-free paper-based test capable of detecting sickle hemoglobin (HbS) in newborn blood samples with a limit of detection of 2% HbS. We validated this newborn paper-based test in a cohort of 159 newborns at an obstetric hospital in Cabinda, Angola.

Influence of red blood cell aggregation on perfusion of an artificial microvascular network.

Objective: RBCs suspended in plasma form multicellular aggregates under low-flow conditions, increasing apparent blood viscosity at low shear rates. It has previously been unclear, however, if RBC aggregation affects microvascular perfusion. Here, we analyzed the impact of RBC aggregation on perfusion and 'capillary' hematocrit in an AMVN at driving pressures ranging from 5 to 60 cm H O to determine if aggregation could improve tissue oxygenation.

Validation of a Low-Cost Paper-Based Screening Test for Sickle Cell Anemia.

Background: The high childhood mortality and life-long complications associated with sickle cell anemia (SCA) in developing countries could be significantly reduced with effective prophylaxis and education if SCA is diagnosed early in life. However, conventional laboratory methods used for diagnosing SCA remain prohibitively expensive and impractical in this setting. This study describes the clinical validation of a low-cost paper-based test for SCA that can accurately identify sickle trait carriers (HbAS) and individuals with SCA (HbSS) among adults and children over 1 year of age.

Shape matters: the effect of red blood cell shape on perfusion of an artificial microvascular network.

Background: The shape of human red blood cells (RBCs) deteriorates progressively throughout hypothermic storage, with echinocytosis being the most prevalent pathway of this morphologic lesion. As a result, each unit of stored blood contains a heterogeneous mixture of cells in various stages of echinocytosis and normal discocytes. Here we studied how the change in shape of RBCs following along the path of the echinocytic transformation affects perfusion of an artificial microvascular network (AMVN).

Deterioration of red blood cell mechanical properties is reduced in anaerobic storage.

Background: Hypothermic storage of red blood cells (RBCs) results in progressive deterioration of the rheological properties of the cells, which may reduce the efficacy of RBC transfusions. Recent studies have suggested that storing RBC units under anaerobic conditions may reduce this storage-induced deterioration.

Materials And Methods: The aim of this study was to compare the rheological properties of conventionally and anaerobically stored RBC and provide a measure of the relationship between oxidative damage to stored RBC and their ability to perfuse microvascular networks.

Washing stored red blood cells in an albumin solution improves their morphologic and hemorheologic properties.

Background: Prolonged storage of red blood cells (RBCs) leads to storage lesions, which may impair clinical outcomes after transfusion. A hallmark of storage lesions is progressive echinocytic shape transformation, which can be partially reversed by washing in albumin solutions. Here we have investigated the impact of this shape recovery on biorheologic variables.

A rapid paper-based test for quantifying sickle hemoglobin in blood samples from patients with sickle cell disease.

Quantification of sickle hemoglobin (HbS) in patients with sickle cell disease (SCD) undergoing hydroxyurea or chronic transfusion therapy is essential to monitoring the effectiveness of these therapies. The clinical monitoring of %HbS using conventional laboratory methods is limited by high per-test costs and long turnaround times usually associated with these methods. Here we demonstrate a simple, rapid, inexpensive paper-based assay capable of quantifying %HbS in blood samples from patients with SCD.

Effect of osmolality on erythrocyte rheology and perfusion of an artificial microvascular network.

Plasma sodium concentration is normally held within a narrow range. It may however vary greatly under pathophysiological conditions. Changes in osmolality lead to either swelling or shrinkage of red blood cells (RBCs).

Simple paper-based test for measuring blood hemoglobin concentration in resource-limited settings.

Background: The measurement of hemoglobin concentration ([Hb]) is performed routinely as a part of a complete blood cell count to evaluate the oxygen-carrying capacity of blood. Devices currently available to physicians and clinical laboratories for measuring [Hb] are accurate, operate on small samples, and provide results rapidly, but may be prohibitively expensive for resource-limited settings. The unavailability of accurate but inexpensive diagnostic tools often precludes proper diagnosis of anemia in low-income developing countries.

A simple, rapid, low-cost diagnostic test for sickle cell disease.

This communication describes a very simple, rapid and inexpensive point-of-care diagnostic test for sickle cell disease (SCD) that can conclusively differentiate between blood samples from normal healthy individuals, sickle cell trait carriers and SCD patients using the characteristic blood stain patterns produced by each sample on paper.