Laboratoire Interuniversitaire de Biologie de la Motricité (LIBM) EA7424, Equipe "Biologie vasculaire et du globule rouge", UCBL1, Lyon, France.
Laboratoire d'Excellence (Labex) GR-Ex, Paris, France.
Sci Rep. 2019 May 1;9(1):6771. doi: 10.1038/s41598-019-43200-y.
Osmotic gradient ektacytometry is the gold standard to assess red blood cell (RBC) deformability. It has been proposed that, when measured in isotonic condition, RBC deformability at low shear stress would depend on membrane elasticity while it would be influenced by internal viscosity when measured at high shear stress, but this hypothesis needs to be further addressed. Healthy RBCs were rigidified by treatment with lysolecithine (LPC), diamide or nystatine associated with hyperosmolar solutions (OSMO), which reduces membrane surface area, decreases membrane elasticity or promotes cell dehydration, respectively. Diamide treatment resulted in a decrease in isotonic RBC deformability at all shear stresses tested (i.e. from 0.3 to 30 Pa). LPC and OSMO treatments caused a decrease in isotonic RBC deformability above 3 Pa only. Isotonic RBC deformability from patients with hereditary spherocytosis or sickle cell disease was mainly decreased above 1.69 Pa. Our findings indicate that decreased isotonic RBC deformability at shear stresses above 3 Pa would be related to a reduction in the surface-area-to-volume ratio and/or to a loss of membrane elasticity and/or to an increase in internal viscosity while a decrease of RBC deformability below 3 Pa would reflect a loss of membrane elasticity.
渗透梯度变形测定法是评估红细胞（RBC）变形性的金标准。有人提出，在等渗条件下测量时，低切应力下 RBC 变形性取决于膜弹性，而在高切应力下测量时则受内部粘度的影响，但这一假设需要进一步研究。通过用溶血磷脂酰胆碱（LPC）、二酰胺或制霉菌素处理并结合高渗溶液（OSMO）使健康的 RBC 刚性化，分别会减少膜表面积、降低膜弹性或促进细胞脱水。二酰胺处理导致在所有测试的剪切应力下（即 0.3 至 30 Pa）等渗 RBC 变形性降低。仅在高于 3 Pa 时，LPC 和 OSMO 处理会导致等渗 RBC 变形性降低。遗传性球形红细胞增多症或镰状细胞病患者的等渗 RBC 变形性主要在高于 1.69 Pa 时降低。我们的研究结果表明，高于 3 Pa 的切应力下等渗 RBC 变形性降低与表面积与体积比的降低以及/或膜弹性的丧失和/或内部粘度的增加有关，而低于 3 Pa 的 RBC 变形性降低则反映了膜弹性的丧失。
