title: The plasma protein fibrinogen stabilizes clusters of red blood cells in microcapillary flows.
abstract: The supply of oxygen and nutrients and the disposal of metabolic waste in the organs depend strongly on how blood, especially red blood cells, flow through the microvascular network. Macromolecular plasma proteins such as fibrinogen cause red blood cells to form large aggregates, called rouleaux, which are usually assumed to be disaggregated in the circulation due to the shear forces present in bulk flow. This leads to the assumption that rouleaux formation is only relevant in the venule network and in arterioles at low shear rates or stasis. Thanks to an excellent agreement between combined experimental and numerical approaches, we show that despite the large shear rates present in microcapillaries, the presence of either fibrinogen or the synthetic polymer dextran leads to an enhanced formation of robust clusters of red blood cells, even at haematocrits as low as 1%. Robust aggregates are shown to exist in microcapillaries even for fibrinogen concentrations within the healthy physiological range. These persistent aggregates should strongly affect cell distribution and blood perfusion in the microvasculature, with putative implications for blood disorders even within apparently asymptomatic subjects.
authors.affiliation: 1] Experimental Physics, Saarland University, 66123 Saarbrücken, Germany [2] Laboratoire Interdisciplinaire de Physique, CNRS - UMR 5588, Université Grenoble I, B.P. 87, 38402 Saint Martin d'Hères Cedex, France [3].
authors.forename: M
authors.initials: M
authors.lastname: Brust
authors.affiliation: 1] Experimental Physics, Saarland University, 66123 Saarbrücken, Germany [2] Laboratoire Interdisciplinaire de Physique, CNRS - UMR 5588, Université Grenoble I, B.P. 87, 38402 Saint Martin d'Hères Cedex, France [3] LMPHE, URAC 12, Faculté des Sciences, Université Mohammed V- Agdal, Rabat, Morocco [4].
authors.forename: O
authors.initials: O
authors.lastname: Aouane
authors.affiliation: 1] Laboratoire Interdisciplinaire de Physique, CNRS - UMR 5588, Université Grenoble I, B.P. 87, 38402 Saint Martin d'Hères Cedex, France [2].
authors.forename: M
authors.initials: M
authors.lastname: Thiébaud
authors.affiliation: Experimental Physics, Saarland University, 66123 Saarbrücken, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Flormann
authors.affiliation: Laboratoire Interdisciplinaire de Physique, CNRS - UMR 5588, Université Grenoble I, B.P. 87, 38402 Saint Martin d'Hères Cedex, France.
authors.forename: C
authors.initials: C
authors.lastname: Verdier
authors.affiliation: Institute for Molecular Cell Biology and Research Centre for Molecular Imaging and Screening, School of Medicine, Saarland University, Building 61, 66421 Homburg/Saar, Germany.
authors.forename: L
authors.initials: L
authors.lastname: Kaestner
authors.affiliation: Institute for Clinical & Experimental Surgery, Saarland University, 66421 Homburg/Saar, Germany.
authors.forename: M W
authors.initials: MW
authors.lastname: Laschke
authors.affiliation: 1] Laboratoire d'Ingénierie Mathématique, Ecole Polytechnique de Tunisie B.P. 743 - 2078 La Marsa, Tunisia [2] Riyadh College of Technology, Technical and Vocational Training Corporation, Riyadh 12433, Saudi Arabia.
authors.forename: H
authors.initials: H
authors.lastname: Selmi
authors.affiliation: LMPHE, URAC 12, Faculté des Sciences, Université Mohammed V- Agdal, Rabat, Morocco.
authors.forename: A
authors.initials: A
authors.lastname: Benyoussef
authors.affiliation: Laboratoire Interdisciplinaire de Physique, CNRS - UMR 5588, Université Grenoble I, B.P. 87, 38402 Saint Martin d'Hères Cedex, France.
authors.forename: T
authors.initials: T
authors.lastname: Podgorski
authors.affiliation: Laboratoire Interdisciplinaire de Physique, CNRS - UMR 5588, Université Grenoble I, B.P. 87, 38402 Saint Martin d'Hères Cedex, France.
authors.forename: G
authors.initials: G
authors.lastname: Coupier
authors.affiliation: Laboratoire Interdisciplinaire de Physique, CNRS - UMR 5588, Université Grenoble I, B.P. 87, 38402 Saint Martin d'Hères Cedex, France.
authors.forename: C
authors.initials: C
authors.lastname: Misbah
authors.affiliation: Experimental Physics, Saarland University, 66123 Saarbrücken, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Wagner
mesh_terms: D000328:Adult; D000818:Animals; D003911:Dextrans / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004903:Erythrocyte Aggregation / Q000187:drug effects*; D004912:Erythrocytes / Q000166:cytology / Q000187:drug effects*; D005340:Fibrinogen / Q000494:pharmacology*; D016650:Fluorescein-5-isothiocyanate / Q000031:analogs & derivatives; D005456:Fluorescent Dyes; D006400:Hematocrit; D006801:Humans; D051379:Mice; D044085:Microfluidics; D055806:Microvessels / Q000502:physiology* / Q000648:ultrastructure; D057054:Molecular Imaging; D010100:Oxygen / Q000378:metabolism; D014741:Video Recording
chemical_list: D003911:Dextrans; D005456:Fluorescent Dyes; C015219:fluorescein isothiocyanate dextran; D005340:Fibrinogen; D016650:Fluorescein-5-isothiocyanate; D010100:Oxygen