A Novel Automated and High-throughput Microfluidic Cell Fusion System Based on Cell-microstructure Interactions under Microflows

Description

Cell fusion can occur naturally in the human body or be caused by chemical/engineering means. During embryogenesis, tissue development/regeneration, and immune responses, some human cells can fuse together. Undesired cell fusion can also be found in tumor progression, generating drug-resistive tumor cells. On the other hand, cell fusion can be applied to integrate desired cell properties, e.g., combining the proliferation of cancer cells and monoclonal antibody production of B lymphocytes as an unlimited antibody source for immunotherapy applications. In the past decades, researchers have developed several cell fusion techniques based on biological, chemical, ultrasound, dielectrophoretic, and laser/thermal fusogens. Nevertheless, many of them are either bio-toxic or can lead to defects in fusion products. There are still technical hurdles to be tackled, e.g. accurate pairing of parent cells and preservation of desired cell functions, for achieving a high-throughput and highly promising cell fusion process and improvements in the corresponding applications. This proposed research aims at addressing the above limitations to offer a novel cell fusion technique called ‘microfluidic cell fusion’. We plan to implement this technique by applying pure hydrodynamics on cells and microstructures as an automated microfluidic cell fusion system. In principle, cell fusion can be achieved by fusing the contacting membrane region between two parent cells. Compared to existing methods, minimal thermal, electrical, and chemical disruptions are induced to components over the entire cells, such that viability and functions can be more likely preserved in the fused cells. With careful design of the flow profiles and microstructures, the microflow-induced stresses around the cells stretch cell membranes and induce their strain energy beyond a barrier level to obtain cell fusion. We will perform theoretical analysis, numerical simulation, and experiments to obtain a sufficient strain-energy-based criterion for the successful microfluidic cell fusion process. Accordingly, we will extend the device design as an array of microfluidic cell fusion microstructures for the required operations. We will also utilize pneumatic microvalves to automate the operation procedures. Together, the proposed platform will achieve automated, high-throughput and promising cell fusion. We strongly believe microfluidic cell fusion will contribute to applications such as monoclonal antibody production, cancer immunotherapy and nuclear reprogramming of somatic cells. This technology also holds great prospects in deeper mechanistic studies on immunology, development biology, cell–cell interactions, and nuclear reprogramming occurred in co-growing cells and tissue engineering.