Comparative rheology of nucleated and non-nucleated red blood cells

Abstract

Deformation and dynamic flow behaviour of nucleated duck erythrocytes were compared to those of nonnucleated human cells during steady flow (at wall shear stresses up to 3 N.m-2) through glass capillaries (diameter between 5 micrometer and 12 micrometer). While the deformation process of both cell species is qualitatively similar, significant quantitative differences demonstrate a lower deformability of the nucleated erythrocytes. In comparison to human cells, the avian red cells exhibit significantly lower stability of orientation during capillary flow. Viscometric measurements show that, in contrast to human red cell suspensions, the relative viscosity of nucleated cell suspensions does not decrease with increasing suspending medium viscosity. The results indicate that the hydrodynamic disturbance caused by avian erythrocytes in the flow of the suspending fluid is more pronounced than that of the mammalian cells. This is due to their lower ability to adapt to local shear forces.

Development and differentiation of the erythroid lineage in mammals

“…Why mammals evolved mechanisms to remove their nucleus during erythroid maturation is not understood. A potential explanation may lie in the observation that mammalian adult erythrocytes are more deformable than the nucleated erythroid cells of birds (Gaehtgens et al, 1981a; Gaehtgens et al, 1981b). Enucleation may, therefore, be an adaptation to allow the mammalian erythrocyte to circulate through narrow capillaries beds.…”

Trim58 Degrades Dynein and Regulates Terminal Erythropoiesis

“…Expulsion of nuclei from erythroblasts (Keerthivasan et al, 2011; Konstantinidis et al, 2012) occurs exclusively in mammals and may represent an evolutionary adaptation to optimize erythrocyte rheology for transport through small capillary beds (Gaehtgens et al, 1981; Mueller et al, 2008). Erythroblast enucleation is preceded by nuclear condensation and requires histone deacetylation (Ji et al, 2010; Popova et al, 2009) and suppression of the Myc proto-oncogene (Jayapal et al, 2010).…”

Blood flow dynamics reflect degree of outflow tract banding in Hamburger–Hamilton stage 18 chicken embryos

“…A parabolic-like velocity profile in the OFT at HH18 [14,18] (figure 2) make this approximation valid. Although adult mammalian blood is non-Newtonian with biconcave red blood cells, embryonic chick blood has spherical red blood cells that are less deformable in flow [27] resulting in a fairly constant viscosity in the physiological shear rate range [28], and thus WSR should be proportional to wall shear stress. The WSR during peak V in the cardiac cycle was compared across all embryos.…”