Assessing the kinetics of oxygen-unloading from red cells using FlowScore, a flow-cytometric proxy of the functional quality of bloodResearch in context
Julija Rabcuka,
Peter A. Smethurst,
Katharina Dammert,
Jarob Saker,
Gemma Aran,
Geraldine M. Walsh,
Joanne C.G. Tan,
Margarita Codinach,
Ken McTaggart,
Denese C. Marks,
Stephan J.L. Bakker,
Amy McMahon,
Emanuele Di Angelantonio,
David J. Roberts,
Slawomir Blonski,
Piotr M. Korczyk,
Atsushi Shirakami,
Rebecca Cardigan,
Pawel Swietach
Affiliations
Julija Rabcuka
Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, UK
Peter A. Smethurst
Component Development Laboratory, NHS Blood and Transplant, Cambridge, UK
Katharina Dammert
Sysmex Europe SE, Bornbarch 1, Norderstedt, 22848, Germany
Jarob Saker
Sysmex Europe SE, Bornbarch 1, Norderstedt, 22848, Germany
Gemma Aran
Cell Laboratory, Banc de Sang i Teixits, Barcelona, Spain
Geraldine M. Walsh
Product and Process Development, Canadian Blood Services, Vancouver, Canada
Joanne C.G. Tan
Research and Development, Australian Red Cross Lifeblood, Sydney, Australia; Sydney Medical School, University of Sydney, Camperdown, Australia
Margarita Codinach
Cell Laboratory, Banc de Sang i Teixits, Barcelona, Spain; Transfusional Medicine Group, Vall d'Hebron Research Institute (VHIR), Universitat Autònoma de Barcelona, Barcelona, Spain
Ken McTaggart
Product and Process Development, Canadian Blood Services, Ottawa, Canada
Denese C. Marks
Research and Development, Australian Red Cross Lifeblood, Sydney, Australia; Sydney Medical School, University of Sydney, Camperdown, Australia
Stephan J.L. Bakker
Department of Internal Medicine, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
Amy McMahon
British Heart Foundation Cardiovascular Epidemiology Unit, Department of Public Health & Primary Care, University of Cambridge, UK; Victor Phillip Dahdaleh Heart and Lung Research Institute, University of Cambridge, Cambridge, UK; National Institute for Health and Care Research Blood and Transplant Research Unit in Donor Health and Behaviour, University of Cambridge, Cambridge, UK
Emanuele Di Angelantonio
British Heart Foundation Cardiovascular Epidemiology Unit, Department of Public Health & Primary Care, University of Cambridge, UK; Victor Phillip Dahdaleh Heart and Lung Research Institute, University of Cambridge, Cambridge, UK; National Institute for Health and Care Research Blood and Transplant Research Unit in Donor Health and Behaviour, University of Cambridge, Cambridge, UK; British Heart Foundation Centre of Research Excellence, University of Cambridge, Cambridge, UK; Health Data Research UK Cambridge, Wellcome Genome Campus and University of Cambridge, Cambridge, UK; Health Data Science Research Centre, Human Technopole, Milan, Italy
David J. Roberts
NHS Blood and Transplant, John Radcliffe Hospital, Oxford, UK; Radcliffe Department of Medicine, University of Oxford, Oxford, UK
Slawomir Blonski
Institute of Fundamental Technological Research Polish Academy of Sciences, Warsaw, Poland
Piotr M. Korczyk
Institute of Fundamental Technological Research Polish Academy of Sciences, Warsaw, Poland
Atsushi Shirakami
Medical and Scientific Affairs, Sysmex Corporation, Kobe, Japan
Rebecca Cardigan
Component Development Laboratory, NHS Blood and Transplant, Cambridge, UK; Department of Haematology, University of Cambridge, UK
Pawel Swietach
Department of Physiology, Anatomy & Genetics, University of Oxford, Oxford, UK; Corresponding author. Department of Physiology, Anatomy & Genetics, Parks Road, Oxford, OX1 3PT, UK.
Summary: Background: Metrics evaluating the functional quality of red blood cells (RBCs) must consider their role in oxygen delivery. Whereas oxygen-carrying capacity is routinely reported using haemoglobin assays, the rate of oxygen exchange is not measured, yet also important for tissue oxygenation. Since oxygen-unloading depends on the diffusion pathlength inside RBCs, cell geometry offers a plausible surrogate. Methods: We related the time-constant of oxygen-unloading (τ), measured using single-cell oxygen saturation imaging, with flow-cytometric variables recorded on a haematology analyser. Experiments compared freshly-drawn RBCs with stored RBCs, wherein metabolic run-down and spherical remodelling hinder oxygen unloading. Findings: Multivariable regression related τ to a ratio of side- and forward-scatter, referred to herein as FlowScore. FlowScore was able to distinguish, with sensitivity and specificity >80%, freshly drawn blood from blood that underwent storage-related kinetic attrition in O2-handling. Moreover, FlowScore predicted τ restoration upon biochemical rejuvenation of stored blood. Since RBC geometry and metabolic state are related, variants of FlowScore estimated [ATP] and [2,3-diphosphoglycerate]. The veracity of FlowScore was confirmed by four blood-banking systems (Australia, Canada, England, Spain). Applying FlowScore to data from the COMPARE study revealed a positive association with the time-delay from sample collection to measurement, which was verified experimentally. The LifeLines dataset revealed age, sex, and smoking among factors affecting FlowScore. Interpretation: We establish FlowScore as a widely-accessible and cost-effective surrogate of RBC oxygen-unloading kinetics. As a metric of a cellular process that is sensitive to storage and disease, we propose FlowScore as an RBC quality marker for blood-banking and haematology. Funding: See Acknowledgements.
