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AbstractSickle cell disease (SCD) is canonically characterized by reduced red blood cell (RBC) deformability, leading to microvascular obstruction and inflammation. Although the biophysical properties of sickle RBCs are known to influence SCD vasculopathy, the contribution of poor RBC deformability to endothelial dysfunction has yet to be fully explored. Leveraging interrelated in vitro and in silico approaches, we introduce a new paradigm of SCD vasculopathy in which poorly deformable sickle RBCs directly cause endothelial dysfunction via mechanotransduction, during which endothelial cells sense and pathophysiologically respond to aberrant physical forces independently of microvascular obstruction, adhesion, or hemolysis. We demonstrate that perfusion of sickle RBCs or pharmacologically-dehydrated healthy RBCs into small venule-sized “endothelialized” microfluidics leads to pathologic physical interactions with endothelial cells that directly induce inflammatory pathways. Using a combination of computational simulations and large venule-sized endothelialized microfluidics, we observed that perfusion of heterogeneous sickle RBC subpopulations with varying deformability, as well as suspensions of dehydrated normal RBCs admixed with normal RBCs, leads to aberrant margination of the less-deformable RBC subpopulations toward the vessel walls, causing localized, increased shear stress. Increased wall stress is dependent on the degree of subpopulation heterogeneity and oxygen tension and leads to inflammatory endothelial gene expression via mechanotransductive pathways. Our multifaceted approach demonstrates that the presence of sickle RBCs with reduced deformability leads directly to pathological physical (ie, direct collisions and/or compressive forces) and shear-mediated interactions with endothelial cells and induces an inflammatory response, thereby elucidating the ubiquity of vascular dysfunction in SCD.
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Cell isolation via spiral microfluidics and the secondary anchor targeted cell release system
Abstract Precision medicine requires high throughput cell isolation and measurement that maintains physiology. Unfortunately, many techniques are slow or alter cell biomarkers cells. This necessitates new approaches, which we achieve by integrating affinity‐based cell isolation with spiral microfluidics. We characterize the device via computational simulations, predicting wall shear stress within an order of magnitude of arterial wall shear stress (~0.2 Pa). We identify that poly‐l‐lysine supplementation preserves cell geometry and improves cell release. We demonstrate preservation of angiogenic biomarker concentrations, measuring 1,000–2,000 vascular endothelial growth factor receptor‐1 per human umbilical vein endothelial cell, which is in line with the previously reported measurements. We attain 76.7 ± 9.0% release of captured cells by integrating thermophoresis and optimizing buffer residence time. Ultimately, we find that combining affinity‐based cell isolation (secondary anchor targeted cell release) with spiral microfluidics offers a fast, biomarker preserving approach needed to individualize medicine.
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- Award ID(s):
- 1923151
- PAR ID:
- 10373288
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- AIChE Journal
- Volume:
- 65
- Issue:
- 12
- ISSN:
- 0001-1541
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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