Rapid and highly efficient capture and release of cancer cells using polymeric microfibers immobilized with enzyme-cleavable peptides

Circulating tumor cells (CTCs) are tumor cells present in the blood. CTCs have attracted much attention as a new tumor marker, because their analysis provides useful information for monitoring cancer progress. In this study, we developed cell-capture and release methods using three-dimensional (3D) microfiber fabrics without damaging the cells. Using functional peptides containing sequences from a polystyrene-binding site and a cleavable site for collagenase type IV, immobilized antibodies on the peptides were able to specifically capture MCF-7 cells in a few minutes and release the captured cells from 3D microfiber fabrics incorporating a vacuum system. The efficiency of cell capture was around 80% and that of the cell release was over 90%. The released cells proliferated normally in culture medium, suggesting that our system will be applicable for the culture and analysis of CTCs. Statement of Significance In this paper, we report cell-capture and release methods using enzyme-cleavable peptides immobilized on microfiber fabrics which has microporous polymeric three-dimensional structures. Detachment and collection of the selectively captured cancer cells are required for ex vivo culture and their further analysis, whereas the cell detachment methods developed so far might cause cell damage, even if cell viability is high enough. Therefore, specific attachment and gentle detachment from the device are required for the accurate analysis of cells. In this study, for capture and release of cancer cells we designed the peptide cleavable by collagenase type IV, which has no target molecule in cells. Our system will be useful for further CTC analysis and might lead to more accurate cancer diagnosis.