title: Microfluidic study of enhanced deposition of sickle cells at acute corners.
abstract: Sickle cell anemia is a blood disorder, known to affect the microcirculation and is characterized by painful vaso-occlusive crises in deep tissues. During the last three decades, many scenarios based on the enhanced adhesive properties of the membrane of sickle red blood cells have been proposed, all related to a final decrease in vessels lumen by cells accumulation on the vascular walls. Up to now, none of these scenarios considered the possible role played by the geometry of the flow on deposition. The question of the exact locations of occlusive events at the microcirculatory scale remains open. Here, using microfluidic devices where both geometry and oxygen levels can be controlled, we show that the flow of a suspension of sickle red blood cells around an acute corner of a triangular pillar or of a bifurcation, leads to the enhanced deposition and aggregation of cells. Thanks to our devices, we follow the growth of these aggregates in time and show that their length does not depend on oxygenation levels; instead, we find that their morphology changes dramatically to filamentous structures when using autologous plasma as a suspending fluid. We finally discuss the possible role played by such aggregates in vaso-occlusive events.
authors.affiliation: Centre National de la Recherche Scientifique UMR 5221, Laboratoire Charles Coulomb, Université de Montpellier, Montpellier, France.
authors.forename: Etienne
authors.initials: E
authors.lastname: Loiseau
authors.affiliation: Centre National de la Recherche Scientifique UMR 5221, Laboratoire Charles Coulomb, Université de Montpellier, Montpellier, France.
authors.forename: Gladys
authors.initials: G
authors.lastname: Massiera
authors.affiliation: Centre National de la Recherche Scientifique UMR 5149, Institut de Mathématiques et de Modélisation de Montpellier, Université de Montpellier, Montpellier, France.
authors.forename: Simon
authors.initials: S
authors.lastname: Mendez
authors.affiliation: Faculté de Médecine, Laboratoire d'Hématologie, Hôpital Saint Eloi, The Cardiovascular Health Research Unit de Montpellier, Montpellier, France.
authors.forename: Patricia Aguilar
authors.initials: PA
authors.lastname: Martinez
authors.affiliation: Centre National de la Recherche Scientifique UMR 5221, Laboratoire Charles Coulomb, Université de Montpellier, Montpellier, France; Centre National de la Recherche Scientifique UMR 5048-UM-Institut National de la Santé et de la Recherche Médicale UMR 1054, Centre de Biochimie Structurale, Montpellier, France. Electronic address: manouk.abkarian@univ-montp2.fr.
authors.forename: Manouk
authors.initials: M
authors.lastname: Abkarian
mesh_terms: D000755:Anemia, Sickle Cell / Q000097:blood* / Q000473:pathology; D001792:Blood Platelets / Q000473:pathology; D004903:Erythrocyte Aggregation; D004912:Erythrocytes / Q000473:pathology*; D006454:Hemoglobins / Q000378:metabolism; D006461:Hemolysis; D006801:Humans; D007962:Leukocytes / Q000473:pathology; D046210:Microfluidic Analytical Techniques; D010100:Oxygen / Q000378:metabolism
chemical_list: D006454:Hemoglobins; D010100:Oxygen