Interference-free Micro/nanoparticle Cell Engineering by Use of High-Throughput Microfluidic Separation.
Engineering cells with active-ingredient-loaded micro/nanoparticles is becoming increasingly popular for imaging and therapeutic applications. A critical yet inadequately addressed issue during its implementation concerns the significant number of particles that remain unbound following the engineering process, which inadvertently generate signals and impart transformative effects onto neighboring nontarget cells. Here we demonstrate that those unbound micro/nanoparticles remaining in solution can be efficiently separated from the particle-labeled cells by implementing a fast, continuous, and high-throughput Dean flow fractionation (DFF) microfluidic device. As proof-of-concept, we applied the DFF microfluidic device for buffer exchange to sort labeled suspension cells (THP-1) from unbound fluorescent dye and dye-loaded micro/nanoparticles. Compared to conventional centrifugation, the depletion efficiency of free dyes or particles was improved 20-fold and the mislabeling of nontarget bystander cells by free particles was minimized. The microfluidic device was adapted to further accommodate heterogeneous-sized mesenchymal stem cells (MSCs). Complete removal of unbound nanoparticles using DFF led to the usage of engineered MSCs without exerting off-target transformative effects on the functional properties of neighboring endothelial cells. Apart from its effectiveness in removing free particles, this strategy is also efficient and scalable. It could continuously process cell solutions with concentrations up to 10(7) cells·mL(-1) (cell densities commonly encountered during cell therapy) without observable loss of performance. Successful implementation of this technology is expected to pave the way for interference-free clinical application of micro/nanoparticle engineered cells.
School of Chemical & Biomedical Engineering, Nanyang Technological University , 62 Nanyang Drive, Singapore 637459.
David C
DC
Yeo
School of Chemical & Biomedical Engineering, Nanyang Technological University , 62 Nanyang Drive, Singapore 637459.
Christian
C
Wiraja
School of Chemical & Biomedical Engineering, Nanyang Technological University , 62 Nanyang Drive, Singapore 637459.
Yingying
Y
Zhou
Lee Kong Chian School of Medicine, Nanyang Technological University , 50 Nanyang Drive, Singapore 637553.
Hui Min
HM
Tay
School of Chemical & Biomedical Engineering, Nanyang Technological University , 62 Nanyang Drive, Singapore 637459.|NTU-Northwestern Institute of Nanomedicine, Nanyang Technological University , 50 Nanyang Avenue, Singapore 639798.
Chenjie
C
Xu
Lee Kong Chian School of Medicine, Nanyang Technological University , 50 Nanyang Drive, Singapore 637553.
Han Wei
HW
Hou
D002021:Buffers; D002448:Cell Adhesion / Q000187:drug effects; D060846:Cell Engineering / Q000379:methods*; D002460:Cell Line; D002465:Cell Movement / Q000187:drug effects; D018920:Coculture Techniques; D003907:Dexamethasone / Q000494:pharmacology; D057166:High-Throughput Screening Assays / Q000379:methods*; D061307:Human Umbilical Vein Endothelial Cells / Q000166:cytology / Q000187:drug effects; D006801:Humans; D007962:Leukocytes / Q000166:cytology / Q000187:drug effects; D059630:Mesenchymal Stem Cells / Q000166:cytology / Q000187:drug effects; D044085:Microfluidics / Q000379:methods*; D053758:Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D012212:Rheology / Q000187:drug effects
D002021:Buffers; D003907:Dexamethasone
Dean flow fractionation; cell engineering; cell separation; microfluidics; nanoparticle