title: Hydrodynamics of a free-flowing leukocyte toward the endothelial wall.
abstract: Leukocyte recruitment is an essential stage of the inflammatory response and although the molecular mechanisms of this process are relatively well known, the influence of the hydrodynamic effects that govern the inflammatory response are still under study. In this paper we made use of the images and experimental parameters obtained by intravital microscopy in an in vivo animal model of inflammation to track the leukocytes trajectories and measure their velocities and diameters. Using a recent validated mathematical model describing the coupled deformation-flow of an individual leukocyte in a microchannel, numerical simulations of an individual and of two leukocytes under flow were performed. The results showed that velocity plays an important role in the motion, deformation and attraction of the cells during an inflammatory response. In fact, for higher inlet velocities the cell movement along the endothelial wall is accelerated and the attraction forces break faster. These results highlight the role of the mechanical properties of the blood, namely the ones influenced by the velocity field, in the case of inflammation.
authors.affiliation: Unidade de Biologia Microvascular e Inflamação, Instituto de Medicina Molecular, Instituto de Bioquímica, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal. Electronic address: anarmsilva@medicina.ulisboa.pt.
authors.forename: Ana Santos
authors.initials: AS
authors.lastname: Silva-Herdade
authors.affiliation: CEMAT/IST, Department of Mathematics, Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal.
authors.forename: Adélia
authors.initials: A
authors.lastname: Sequeira
authors.affiliation: Unidade de Biologia Microvascular e Inflamação, Instituto de Medicina Molecular, Instituto de Bioquímica, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.
authors.forename: Ângelo
authors.initials: Â
authors.lastname: Calado
authors.affiliation: Unidade de Biologia Microvascular e Inflamação, Instituto de Medicina Molecular, Instituto de Bioquímica, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal.
authors.forename: Carlota
authors.initials: C
authors.lastname: Saldanha
authors.affiliation: CEMAT/IST, Department of Mathematics, Instituto Superior Técnico, Universidade de Lisboa, Lisboa, Portugal.
authors.forename: Oualid
authors.initials: O
authors.lastname: Kafi
mesh_terms: D000818:Animals; D001783:Blood Flow Velocity; D003198:Computer Simulation; D004195:Disease Models, Animal; D004730:Endothelium, Vascular / Q000276:immunology / Q000503:physiopathology*; D020342:Finite Element Analysis; D018056:Hemorheology; D057446:Hydrodynamics; D007249:Inflammation / Q000097:blood / Q000276:immunology / Q000503:physiopathology*; D000069416:Intravital Microscopy; D036904:Leukocyte Rolling; D007962:Leukocytes / Q000276:immunology*; D008297:Male; D008822:Mice, Transgenic; D008955:Models, Cardiovascular; D009716:Numerical Analysis, Computer-Assisted; D012039:Regional Blood Flow; D013997:Time Factors
keywords: Coupled deformation-flow; Inflammatory response; Intravital microscopy; Leukocyte; Mathematical model; Numerical simulations