Efficient release of immunocaptured cells using coiled-coils in a microfluidic device.

Area of Science:

• Biotechnology
• Microfluidics
• Cell Biology

Background:

• Label-free and affinity-based cell separation methods face challenges in efficiently releasing captured cells without compromising their integrity.
• Maintaining cell structure, phenotype, and function post-separation is crucial for downstream applications.

Purpose of the Study:

• To develop a microfluidic platform for label-free immunocapture and efficient release of target cells.
• To achieve cell release with minimal biochemical and biophysical perturbations, preserving cell characteristics.

Main Methods:

• Utilized a microfluidic system employing self-assembling heterodimerizing coiled-coils (A and B) for cell capture.
• Functionalized microchannels with antibodies and coiled-coil A for target cell capture.
• Employed a liquid flow containing B-PEG (coiled-coil B conjugated with polyethylene glycol) at controlled low shear stress for cell release.

Main Results:

• Achieved high capture selectivity (96.3% ± 1.8%) and release efficiency (92.5% ± 3.8%) for human umbilical vein endothelial cells (HUVECs).
• Demonstrated minimal perturbation to released cells, with no attached antibodies or cleaved surface molecules.
• Quantified a capture capacity of 10,735 ± 1897 cells per cm² at a shear stress of 1 dyn cm^-2.

Conclusions:

• The developed microfluidic platform enables efficient and gentle isolation of target cells.
• The B-PEG conjugate serves as a universal trigger for cell release, adaptable for various cell types recognizable by antibodies.
• This technology offers a promising solution for cell separation while preserving cell viability and function.