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Williams DC, Wood DK. High-throughput quantification of red blood cell deformability and oxygen saturation to probe mechanisms of sickle cell disease. Proc Natl Acad Sci U S A 2023; 120:e2313755120. [PMID: 37983504 PMCID: PMC10691249 DOI: 10.1073/pnas.2313755120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2023] [Accepted: 10/23/2023] [Indexed: 11/22/2023] Open
Abstract
The complex, systemic pathology of sickle cell disease is driven by multiple mechanisms including red blood cells (RBCs) stiffened by polymerized fibers of deoxygenated sickle hemoglobin. A critical step toward understanding the pathologic role of polymer-containing RBCs is quantifying the biophysical changes in these cells in physiologically relevant oxygen environments. We have developed a microfluidic platform capable of simultaneously measuring single RBC deformability and oxygen saturation under controlled oxygen and shear stress. We found that RBCs with detectable amounts of polymer have decreased oxygen affinity and decreased deformability. Surprisingly, the deformability of the polymer-containing cells is oxygen-independent, while the fraction of these cells increases as oxygen decreases. We also find that some fraction of these cells is present at most physiologic oxygen tensions, suggesting a role for these cells in the systemic pathologies. Additionally, the ability to measure these pathological cells should provide clearer targets for evaluating therapies.
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Affiliation(s)
- Dillon C. Williams
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN55455
| | - David K. Wood
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN55455
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2
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Fay ME, Oshinowo O, Iffrig E, Fibben KS, Caruso C, Hansen S, Musick JO, Valdez JM, Azer SS, Mannino RG, Choi H, Zhang DY, Williams EK, Evans EN, Kanne CK, Kemp ML, Sheehan VA, Carden MA, Bennett CM, Wood DK, Lam WA. iCLOTS: open-source, artificial intelligence-enabled software for analyses of blood cells in microfluidic and microscopy-based assays. Nat Commun 2023; 14:5022. [PMID: 37596311 PMCID: PMC10439163 DOI: 10.1038/s41467-023-40522-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 07/28/2023] [Indexed: 08/20/2023] Open
Abstract
While microscopy-based cellular assays, including microfluidics, have significantly advanced over the last several decades, there has not been concurrent development of widely-accessible techniques to analyze time-dependent microscopy data incorporating phenomena such as fluid flow and dynamic cell adhesion. As such, experimentalists typically rely on error-prone and time-consuming manual analysis, resulting in lost resolution and missed opportunities for innovative metrics. We present a user-adaptable toolkit packaged into the open-source, standalone Interactive Cellular assay Labeled Observation and Tracking Software (iCLOTS). We benchmark cell adhesion, single-cell tracking, velocity profile, and multiscale microfluidic-centric applications with blood samples, the prototypical biofluid specimen. Moreover, machine learning algorithms characterize previously imperceptible data groupings from numerical outputs. Free to download/use, iCLOTS addresses a need for a field stymied by a lack of analytical tools for innovative, physiologically-relevant assays of any design, democratizing use of well-validated algorithms for all end-user biomedical researchers who would benefit from advanced computational methods.
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Affiliation(s)
- Meredith E Fay
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Aflac Cancer Center and Blood Disorders Service of Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA
- Winship Cancer Institute of Emory University, Atlanta, GA, USA
- Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
- Institute for Electronics and Nanotechnology, Georgia Institute of Technology, Atlanta, GA, USA
| | - Oluwamayokun Oshinowo
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Aflac Cancer Center and Blood Disorders Service of Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA
- Winship Cancer Institute of Emory University, Atlanta, GA, USA
- Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
- Institute for Electronics and Nanotechnology, Georgia Institute of Technology, Atlanta, GA, USA
| | - Elizabeth Iffrig
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA
- Department of Medicine, Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, Emory University, Atlanta, GA, USA
| | - Kirby S Fibben
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Aflac Cancer Center and Blood Disorders Service of Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA
- Winship Cancer Institute of Emory University, Atlanta, GA, USA
- Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
- Institute for Electronics and Nanotechnology, Georgia Institute of Technology, Atlanta, GA, USA
| | - Christina Caruso
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Aflac Cancer Center and Blood Disorders Service of Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA
| | - Scott Hansen
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA
| | - Jamie O Musick
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Aflac Cancer Center and Blood Disorders Service of Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA
| | - José M Valdez
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA
| | - Sally S Azer
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Aflac Cancer Center and Blood Disorders Service of Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA
- Institute for Electronics and Nanotechnology, Georgia Institute of Technology, Atlanta, GA, USA
| | - Robert G Mannino
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Aflac Cancer Center and Blood Disorders Service of Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA
- Winship Cancer Institute of Emory University, Atlanta, GA, USA
- Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
- Institute for Electronics and Nanotechnology, Georgia Institute of Technology, Atlanta, GA, USA
| | - Hyoann Choi
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Aflac Cancer Center and Blood Disorders Service of Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA
- Winship Cancer Institute of Emory University, Atlanta, GA, USA
- Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
- Institute for Electronics and Nanotechnology, Georgia Institute of Technology, Atlanta, GA, USA
| | - Dan Y Zhang
- Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
- The George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Evelyn K Williams
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Aflac Cancer Center and Blood Disorders Service of Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA
- Winship Cancer Institute of Emory University, Atlanta, GA, USA
- Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
- Institute for Electronics and Nanotechnology, Georgia Institute of Technology, Atlanta, GA, USA
| | - Erica N Evans
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Aflac Cancer Center and Blood Disorders Service of Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA
| | - Celeste K Kanne
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Aflac Cancer Center and Blood Disorders Service of Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA
| | - Melissa L Kemp
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA
- Winship Cancer Institute of Emory University, Atlanta, GA, USA
- Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA
| | - Vivien A Sheehan
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Aflac Cancer Center and Blood Disorders Service of Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA
| | - Marcus A Carden
- Department of Epidemiology, Gillings School of Public Health, University of North Carolina, Chapel Hill, NC, USA
| | - Carolyn M Bennett
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Aflac Cancer Center and Blood Disorders Service of Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA
| | - David K Wood
- Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN, USA
| | - Wilbur A Lam
- The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology & Emory University, Atlanta, GA, USA.
- Department of Pediatrics, Division of Pediatric Hematology/Oncology, Aflac Cancer Center and Blood Disorders Service of Children's Healthcare of Atlanta, Emory University School of Medicine, Atlanta, GA, USA.
- Winship Cancer Institute of Emory University, Atlanta, GA, USA.
- Parker H. Petit Institute of Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, GA, USA.
- Institute for Electronics and Nanotechnology, Georgia Institute of Technology, Atlanta, GA, USA.
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3
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Druzak S, Iffrig E, Roberts BR, Zhang T, Fibben KS, Sakurai Y, Verkerke HP, Rostad CA, Chahroudi A, Schneider F, Wong AKH, Roberts AM, Chandler JD, Kim SO, Mosunjac M, Mosunjac M, Geller R, Albizua I, Stowell SR, Arthur CM, Anderson EJ, Ivanova AA, Ahn J, Liu X, Maner-Smith K, Bowen T, Paiardini M, Bosinger SE, Roback JD, Kulpa DA, Silvestri G, Lam WA, Ortlund EA, Maier CL. Multiplatform analyses reveal distinct drivers of systemic pathogenesis in adult versus pediatric severe acute COVID-19. Nat Commun 2023; 14:1638. [PMID: 37015925 PMCID: PMC10073144 DOI: 10.1038/s41467-023-37269-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Accepted: 03/08/2023] [Indexed: 04/06/2023] Open
Abstract
The pathogenesis of multi-organ dysfunction associated with severe acute SARS-CoV-2 infection remains poorly understood. Endothelial damage and microvascular thrombosis have been identified as drivers of COVID-19 severity, yet the mechanisms underlying these processes remain elusive. Here we show alterations in fluid shear stress-responsive pathways in critically ill COVID-19 adults as compared to non-COVID critically ill adults using a multiomics approach. Mechanistic in-vitro studies, using microvasculature-on-chip devices, reveal that plasma from critically ill COVID-19 adults induces fibrinogen-dependent red blood cell aggregation that mechanically damages the microvascular glycocalyx. This mechanism appears unique to COVID-19, as plasma from non-COVID sepsis patients demonstrates greater red blood cell membrane stiffness but induces less significant alterations in overall blood rheology. Multiomics analyses in pediatric patients with acute COVID-19 or the post-infectious multi-inflammatory syndrome in children (MIS-C) demonstrate little overlap in plasma cytokine and metabolite changes compared to adult COVID-19 patients. Instead, pediatric acute COVID-19 and MIS-C patients show alterations strongly associated with cytokine upregulation. These findings link high fibrinogen and red blood cell aggregation with endotheliopathy in adult COVID-19 patients and highlight differences in the key mediators of pathogenesis between adult and pediatric populations.
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Grants
- T32 GM142617 NIGMS NIH HHS
- P51 OD011132 NIH HHS
- R35 HL145000 NHLBI NIH HHS
- K99 HL150626 NHLBI NIH HHS
- T32 GM135060 NIGMS NIH HHS
- F31 DK126435 NIDDK NIH HHS
- R01 DK115213 NIDDK NIH HHS
- R38 AI140299 NIAID NIH HHS
- A F31 training fellowship from the National Institutes of Health National Institute of Diabetes and Digestive and Kidney Diseases (NIH/NIDDK), F31DK126435, supported S.A.D during the duration of this work. Stimulating Access to Research in Residency of the National Institutes of Health under Award Number R38AI140299 supported E.I. R35HL145000 supported E.I, Y.S, K.S.F and W.A.L. National Institutes of Health National Heart, Lung, and Blood Institute (NIH/NHLBI) HL150658, awarded to J.D.C. A training grant supported by the Biochemistry and Cell Developmental Biology program (BCDB) at Emory university, T32GM135060-02S1, to S.O.K. NIH/NIDDK Grant R01-DK115213 and Winship Synergy Award to E.A.O. NIH/NHLBI K99 HL150626-01 awarded to C.L.M. The lipidomics and metabolomics experiments were supported by the Emory Integrated Metabolomics and Lipidomics Core, which is subsidized by the Emory University School of Medicine and is one of the Emory Integrated Core Facilities.
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Affiliation(s)
- Samuel Druzak
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Elizabeth Iffrig
- Department of Medicine, Emory University School of Medicine, Atlanta, GA, USA
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Blaine R Roberts
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
- Department of Neurology, Emory University School of Medicine, Atlanta, GA, USA
| | - Tiantian Zhang
- Emory Integrated Metabolomics and Lipidomics Core, Emory University School of Medicine, Atlanta, GA, USA
| | - Kirby S Fibben
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
| | - Yumiko Sakurai
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| | - Hans P Verkerke
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA, USA
| | - Christina A Rostad
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
- Children's Healthcare of Atlanta, Atlanta, GA, USA
| | - Ann Chahroudi
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
- Children's Healthcare of Atlanta, Atlanta, GA, USA
| | - Frank Schneider
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA, USA
| | - Andrew Kam Ho Wong
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA, USA
- Emory National Primate Research Center, Atlanta, GA, USA
| | - Anne M Roberts
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Joshua D Chandler
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
- Children's Healthcare of Atlanta, Atlanta, GA, USA
| | - Susan O Kim
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| | - Mario Mosunjac
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA, USA
| | - Marina Mosunjac
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA, USA
| | - Rachel Geller
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA, USA
- Georgia Bureau of Investigation, Decatur, GA, USA
| | - Igor Albizua
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA, USA
| | - Sean R Stowell
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Connie M Arthur
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Evan J Anderson
- Department of Medicine, Emory University School of Medicine, Atlanta, GA, USA
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
- Children's Healthcare of Atlanta, Atlanta, GA, USA
| | - Anna A Ivanova
- Emory Integrated Metabolomics and Lipidomics Core, Emory University School of Medicine, Atlanta, GA, USA
| | - Jun Ahn
- Emory Integrated Metabolomics and Lipidomics Core, Emory University School of Medicine, Atlanta, GA, USA
| | - Xueyun Liu
- Emory Integrated Metabolomics and Lipidomics Core, Emory University School of Medicine, Atlanta, GA, USA
| | - Kristal Maner-Smith
- Emory Integrated Metabolomics and Lipidomics Core, Emory University School of Medicine, Atlanta, GA, USA
| | - Thomas Bowen
- Emory Integrated Metabolomics and Lipidomics Core, Emory University School of Medicine, Atlanta, GA, USA
| | - Mirko Paiardini
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA, USA
- Emory National Primate Research Center, Atlanta, GA, USA
| | - Steve E Bosinger
- Department of Medicine, Emory University School of Medicine, Atlanta, GA, USA
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA, USA
- Emory National Primate Research Center, Atlanta, GA, USA
- Emory Vaccine Center, Atlanta, GA, USA
| | - John D Roback
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA, USA
| | - Deanna A Kulpa
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA, USA
- Emory National Primate Research Center, Atlanta, GA, USA
- Center for AIDS Research, Emory University, Atlanta, GA, USA
| | - Guido Silvestri
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA, USA
- Emory National Primate Research Center, Atlanta, GA, USA
- Emory Vaccine Center, Atlanta, GA, USA
- Center for AIDS Research, Emory University, Atlanta, GA, USA
| | - Wilbur A Lam
- Wallace H Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA, USA.
- Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA.
- Children's Healthcare of Atlanta, Atlanta, GA, USA.
| | - Eric A Ortlund
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA.
- Emory Integrated Metabolomics and Lipidomics Core, Emory University School of Medicine, Atlanta, GA, USA.
| | - Cheryl L Maier
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA, USA.
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Musick JO, Fibben KS, Lam WA. Hyperviscosity syndromes; hemorheology for physicians and the use of microfluidic devices. Curr Opin Hematol 2022; 29:290-296. [PMID: 35916537 PMCID: PMC9547821 DOI: 10.1097/moh.0000000000000735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW Hyperviscosity syndromes can lead to significant morbidity and mortality. Existing methods to measure microcirculatory rheology are not readily available and limited in relevance and accuracy at this level. In this review, we review selected hyperviscosity syndromes and the advancement of their knowledge using microfluidic platforms. RECENT FINDINGS Viscosity changes drastically at the microvascular level as the physical properties of the cells themselves become the major determinants of resistance to blood flow. Current, outdated viscosity measurements only quantify whole blood or serum. Changes in blood composition, cell number, or the physical properties themselves lead to increased blood viscosity. Given the significant morbidity and mortality from hyperviscosity syndromes, new biophysical tools are needed and being developed to study microvascular biophysical and hemodynamic conditions at this microvascular level to help predict those at risk and guide therapeutic treatment. SUMMARY The use of 'lab-on-a-chip' technology continues to rise to relevance with point of care, personalized testing and medicine as customizable microfluidic platforms enable independent control of many in vivo factors and are a powerful tool to study microcirculatory hemorheology.
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Affiliation(s)
- Jamie O. Musick
- Department of Pediatrics, Aflac Cancer and Blood Disorders Center of Children’s Healthcare of Atlanta, Emory University School of Medicine, Atlanta, Georgia 30322, USA
| | - Kirby S. Fibben
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia 30332, USA
| | - Wilbur A. Lam
- Department of Pediatrics, Aflac Cancer and Blood Disorders Center of Children’s Healthcare of Atlanta, Emory University School of Medicine, Atlanta, Georgia 30322, USA
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia 30332, USA
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5
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Hansen S, Wood DK. Simultaneous quantification of blood rheology and oxygen saturation to evaluate affinity-modifying therapies in sickle cell disease. LAB ON A CHIP 2022; 22:4141-4150. [PMID: 36134535 PMCID: PMC10165883 DOI: 10.1039/d2lc00623e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Sickle cell blood demonstrates oxygen-dependent flow behavior as a result of HbS polymerization during hypoxia, and these rheological changes provide a biophysical metric that can be used to quantify the pathological behavior of the blood. Relating these rheological changes directly to hemoglobin oxygen saturation would improve our understanding of SCD pathogenesis and the potential effects of therapeutic drugs. Towards this end, we have developed a microfluidic platform capable of spectrophotometric quantification of Hb-O2 saturation and simultaneous evaluation of the accompanying rheological changes in SCD blood flow. We demonstrated the ability to measure changes in Hb-O2 affinity and a restoration of oxygen-independent blood flow behavior after incubation with voxelotor, an oxygen affinity modifying drug approved for use in SCD. We also identified regimes in Hb-O2 saturation where the effects of HbS polymerization begin to take effect in contributing to pathological flow behavior, independent of voxelotor treatment. In contrast, incubation with voxelotor recovered oxygen-dependent blood flow over a range of PO2, providing a framework for understanding voxelotor's therapeutic effect in lowering the PO2 at which the requisite Hb-O2 saturation is reached to observe pathological blood flow. These results help explain the mechanistic effects of voxelotor and show the potential of this platform to identify affinity-modifying compounds and evaluate their therapeutic effect on blood flow.
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Affiliation(s)
- Scott Hansen
- Department of Biomedical Engineering, University of Minnesota, Minneapolis 55409, USA.
| | - David K Wood
- Department of Biomedical Engineering, University of Minnesota, Minneapolis 55409, USA.
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Cryptography-Based Medical Signal Securing Using Improved Variation Mode Decomposition with Machine Learning Techniques. COMPUTATIONAL INTELLIGENCE AND NEUROSCIENCE 2022; 2022:7307552. [PMID: 36131899 PMCID: PMC9484937 DOI: 10.1155/2022/7307552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 07/16/2022] [Accepted: 07/21/2022] [Indexed: 11/20/2022]
Abstract
There is no question about the value that digital signal processing brings to the area of biomedical research. DSP processors are used to sample and process the analog inputs that are received from a human organ. These inputs come from the organ itself. DSP processors, because of their multidimensional data processing nature, are the electrical components that take up the greatest space and use the most power. In this age of digital technology and electronic gizmos, portable biomedical devices represent an essential step forward in technological advancement. Electrocardiogram (ECG) units are among the most common types of biomedical equipment, and their functions are absolutely necessary to the process of saving human life. In the latter part of the 1990s, portable electrocardiogram (ECG) devices began to appear on the market, and research into their signal processing and electronics design capabilities continues today. System-on-chip (SoC) design refers to the process through which the separate computing components of a DSP unit are combined onto a single chip in order to achieve greater power and space efficiency. In the design of biomedical DSP devices, this body of research presents a number of different solutions for reducing power consumption and space requirements. Using serial or parallel data buses, which are often the region that consumes the most power, it is possible to send data between the system-on-chip (SoC) and other components. To cut down on the number of needless switching operations that take place during data transmission, a hybrid solution that makes use of the shift invert bus encoding scheme has been developed. Using a phase-encoded shift invert bus encoding approach, which embeds the two-bit indication lines into a single-bit encoded line, is one way to solve the issue of having two distinct indicator bits. This method reduces the problem. The PESHINV approach is compared to the SHINV method that already exists, and the comparison reveals that the suggested PESHINV method reduces the total power consumption of the encoding circuit by around 30 percent. The computing unit of the DSP processor is the target of further optimization efforts. Virtually, all signal processing methods need memory and multiplier circuits to function properly.
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7
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Vunnam N, Hansen S, Williams DC, Been M, Lo CH, Pandey AK, Paulson CN, Rohde JA, Thomas DD, Sachs JN, Wood DK. Fluorescence Lifetime Measurement of Prefibrillar Sickle Hemoglobin Oligomers as a Platform for Drug Discovery in Sickle Cell Disease. Biomacromolecules 2022; 23:3822-3830. [PMID: 35944154 PMCID: PMC9472799 DOI: 10.1021/acs.biomac.2c00671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Revised: 07/22/2022] [Indexed: 11/30/2022]
Abstract
The molecular origin of sickle cell disease (SCD) has been known since 1949, but treatments remain limited. We present the first high-throughput screening (HTS) platform for discovering small molecules that directly inhibit sickle hemoglobin (HbS) oligomerization and improve blood flow, potentially overcoming a long-standing bottleneck in SCD drug discovery. We show that at concentrations far below the threshold for nucleation and rapid polymerization, deoxygenated HbS forms small assemblies of multiple α2β2 tetramers. Our HTS platform leverages high-sensitivity fluorescence lifetime measurements that monitor these temporally stable prefibrillar HbS oligomers. We show that this approach is sensitive to compounds that inhibit HbS polymerization with or without modulating hemoglobin oxygen binding affinity. We also report the results of a pilot small-molecule screen in which we discovered and validated several novel inhibitors of HbS oligomerization.
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Affiliation(s)
- Nagamani Vunnam
- Department
of Biomedical Engineering, University of
Minnesota, Minneapolis, Minnesota 55455, United States
| | - Scott Hansen
- Department
of Biomedical Engineering, University of
Minnesota, Minneapolis, Minnesota 55455, United States
| | - Dillon C. Williams
- Department
of Biomedical Engineering, University of
Minnesota, Minneapolis, Minnesota 55455, United States
| | - MaryJane
Olivia Been
- Department
of Biomedical Engineering, University of
Minnesota, Minneapolis, Minnesota 55455, United States
| | - Chih Hung Lo
- Department
of Biomedical Engineering, University of
Minnesota, Minneapolis, Minnesota 55455, United States
| | - Anil K. Pandey
- Department
of Biomedical Engineering, University of
Minnesota, Minneapolis, Minnesota 55455, United States
| | - Carolyn N. Paulson
- Department
of Biomedical Engineering, University of
Minnesota, Minneapolis, Minnesota 55455, United States
| | - John A. Rohde
- Department
of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - David D. Thomas
- Department
of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Jonathan N. Sachs
- Department
of Biomedical Engineering, University of
Minnesota, Minneapolis, Minnesota 55455, United States
| | - David K. Wood
- Department
of Biomedical Engineering, University of
Minnesota, Minneapolis, Minnesota 55455, United States
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