Natural Biointerface Based on Cancer Cell Membranes for Specific Capture and Release of Circulating Tumor Cells

Circulating tumor cells (CTCs) are an important part of liquid biopsy as they represent a potentially rich source of information for cancer diagnosis, monitoring, prognosis, and treatment guidance. It has been proved that the nanotopography interaction between cells and the surface of CTC detection platforms can significantly improve the capture efficiency of CTCs, whereas many mature nanostructure substrates have been developed based on chemistry materials. In this work, a natural biointerface with unique biological properties is fabricated for efficient isolation and nondestructive release of CTCs from blood samples using the cancer cell membranes. The cell membrane interfaces are proved to have a good antiadhesion property for nonspecific cells because of their own electronegativity. A natural surface nanostructure is provided by the cancer cell membrane to nicely match with the surface nanotopography of CTCs. Bovine serum albumin (BSA) as a linker and DNA aptamer against the epithelial cell adhesion molecule (EpCAM) as a specific affinity molecule are then introduced onto the cell membrane interfaces to achieve the highly efficient and specific capture of CTCs. Finally, the captured target cells can be intactly released from the substrate using the complementary DNA sequence with controlling the incubation time. This study provides a smart strategy in the development of a natural biological interface for the isolation and release of CTCs with high purity.