Anti-margination of microparticles and platelets in the vicinity of branching vessels

C. Bächer; A. Kihm; L. Schrack; L. Kaestner; M. W. Laschke; C. Wagner; S. Gekle

doi:10.1016/j.bpj.2018.06.013

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arXiv · 1801.08708

Anti-margination of microparticles and platelets in the vicinity of branching vessels

C. Bächer·A. Kihm·L. Schrack·L. Kaestner·M. W. Laschke·C. Wagner·S. Gekle

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Abstract

We investigate the margination of microparticles/platelets in blood flow through complex geometries typical for in vivo vessel networks: a vessel confluence and a bifurcation. Using 3D Lattice-Boltzmann simulations, we confirm that behind the confluence of two vessels a cell-free layer devoid of red blood cells develops in the channel center. Despite its small size of roughly one micrometer, this central cell-free layer persists for up to 100 $μ$m after the confluence. Most importantly, we show from simulations that this layer also contains a significant amount of microparticles/platelets and validate this result by in vivo microscopy in mouce venules. At bifurcations, however, a similar effect does not appear and margination is largely unaffected by the geometry. This anti-margination towards the vessel center after a confluence may explain in vivo observations by Woldhuis et al. [Am. J. Physiol. 262, H1217 (1992)] where platelet concentrations near the vessel wall are seen to be much higher on the arteriolar side (containing bifurcations) than on the venular side (containing confluences) of the vascular system.

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C. Bächer, A. Kihm, L. Schrack, L. Kaestner, M. W. Laschke, C. Wagner, S. Gekle. 2018-05-11. Anti-margination of microparticles and platelets in the vicinity of branching vessels. https://doi.org/10.1016/j.bpj.2018.06.013

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