AUTHOR=Namgung Bumseok , Ng Yan Cheng , Leo Hwa Liang , Rifkind Joseph M. , Kim Sangho 

TITLE=Near-Wall Migration Dynamics of Erythrocytes in Vivo: Effects of Cell Deformability and Arteriolar Bifurcation

JOURNAL=Frontiers in Physiology

VOLUME=8

YEAR=2017

URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2017.00963

DOI=10.3389/fphys.2017.00963

ISSN=1664-042X

ABSTRACT=<p>Red blood cell (RBC) deformability has a significant impact on microcirculation by affecting cell dynamics. Despite previous studies that have demonstrated the margination of rigid cells and particles <italic>in vitro</italic>, little information is available on the <italic>in vivo</italic> margination of deformability-impaired RBCs under physiological flow and hematocrit conditions. Thus, in this study, we examined how the deformability-dependent, RBC migration alters the cell distribution under physiological conditions, particularly in arteriolar network flows. The hardened RBCs (<italic>h</italic>RBCs) were found to preferentially flow near the vessel walls of small arterioles (diameter = 47.1–93.3 μm). The majority of the <italic>h</italic>RBCs (63%) were marginated within the range of 0.7<italic>R</italic>-0.9<italic>R</italic> (<italic>R</italic>: radial position normalized by vessel radius), indicating that the <italic>h</italic>RBCs preferentially accumulated near the vessel walls. The laterally marginated <italic>h</italic>RBCs maintained their lateral positions near the walls while traversing downstream with attenuated radial dispersion. In addition, the immediate displacement of RBCs while traversing a bifurcation also contributes to the near-wall accumulation of <italic>h</italic>RBCs. The notable difference in the inward migration between the marginated <italic>n</italic>RBCs and <italic>h</italic>RBCs after bifurcations further supports the potential role of bifurcations in the accumulation of <italic>h</italic>RBCs near the walls.</p>