Title: High-Throughput Measurement of the Flexibility of Human Red Blood Cells: A Unified Computational and Microfluidic Approach

Abstract: Deformability is a critical feature of red blood cells (RBCs) within their 100-120 day life-span through the blood circulation system. It is a particularly important factor in their flow through the microcirculation capillaries or the splenic sinusoids. Deformability is affected by many pathological conditions and its alteration can impact the pathophysiology of many diseases. While primary reasons for altered deformability are hereditary, mutation, or parasitic invasion, there are also many secondary biochemical pathways which influence RBC morphology, biochemistry, and biomechanics. As a result, RBC deformability is altered in many blood related diseases such as diabetes and sepsis. In addition, it has recently been discovered that, even neurodegenerative diseases and COVID19 can be correlated to the deformability of RBCs.

RBC structure and deformability are largely governed by the membrane shear modulus.  State-of-the-art methods to measure the shear modulus of RBCs are not high-throughput and, microfluidic platforms for high-throughput measurements of RBC mechanical properties have not yet enabled measurement of the shear modulus. These limitations challenge the development of diagnostic devices based on RBC shear modulus biomarkers.   In this talk, we will demonstrate a high-throughput microfluidic platform, coupled with high-fidelity computational simulations to address this significant gap in technology. We will described in some detail the Immersed Boundary Simulations necessary to computationally simulate the solution surface of RBC shape in a microfluidic flow that is necessary to interpret the microfluidic measurements. In contrast with existing technologies, this approach allows us to measure the shear modulus of individual RBCs and generate shear modulus distributions (for a given individual or multiple individuals) including measurements of thousands of cells in a few minutes of experimental data acquisition. To the best of our knowledge, this work is the first to measure the shear moduli of thousands of RBCs and we will finish the talk with applications of the device in measuring biomarkers for disease.

Bio: Eric Shaqfeh is the Lester Levi Carter Professor of Chemical Engineering at Stanford University.  He is also a Professor of Mechanical Engineering,  and most recently (as of 2004) a faculty member in the Institute of Computational and Mathematical Engineering at Stanford.

Shaqfeh’s current research interests include non-Newtonian fluid mechanics (especially in the area of elastic instabilities, and turbulent drag reduction), nonequilibrium polymer statistical dynamics (focusing on single molecules studies of DNA), and suspension mechanics (particularly particles in viscoelastic fluids and particles/vesicles/capsules in microfluidics).  He has authored or co-authored over 200 publications and now serves as an Associate Editor of the Physical Review Fluids. He also serves on the boards of four other international journals.

Shaqfeh has received a number of awards including the 2011 Bingham Medal from the Society of Rheology and the 2018 Alpha Chi Sigma Award from the AICHE. He is a Fellow of the American Physical Society (2001) and the Society of Rheology(2015), as well as  a member of the National Academy of Engineering (2013).

Seminars are held on select Wednesdays from 12:00 noon-1pm, Eastern/New York time.