Novel immunoassay capable of capturing circulating tumor cells

Written by Cameron Low, Future Science Group

A team of bioengineers from Thayer School of Engineering at Dartmouth (NH, USA) have demonstrated their novel immunomagnetic system, which couples nanoengineered particles and microfluidic chips, is capable of capturing and manipulating circulating tumor cells (CTCs). The system could be used to quantify rare tumor markers, allowing oncologists to make prognoses and select therapies. The immunoassay can also be combined with fluorescent microscopy for cancer cell imaging.

Circulating tumor cells are shed into the blood by invasive cancers; detection of CTCs at an early stage could help physicians determine a patient’s prognosis and select suitable therapies. It is conceived that the capture of CTCs may revolutionize risk assessment, treatment selection, response monitoring and development of novel therapies.

The team, led by John XJ Zhang, Professor of engineering at the Thayer School of Engineering at Dartmouth, focused on the creation of a new interface between living cells and hybrid microsystems. This new interface allowed for the formation of bioanalytical microsystems for point-of-care and globally relevant diagnostic applications.

“The concept is to use novel cell-machine interfaces, integrated sensing, actuation and biomarker recognition functionalities to isolate these rare cells (1 per 109 hematologic cells) from whole blood to determine malignancy unambiguously,” Zhang commented. “We will base the quantitative assessment on multiple tumor markers.”

The research group successfully demonstrated that they can combine the benefits of an immunomagnetic assay with microfluidic technology for high-throughput CTC screening, creating a highly sensitive assay with increased cell capture rate and reduced cell aggregation. The assay is also suitable for single cell level analyses of CTCs.

Zhang’s end goal is to bring the technology from the bench to clinics, which he hopes will enable doctors to diagnose and manage cancer via simple blood tests.

Sources: Chen P, Huang Y-Y, Hoshino K et al. Microscale Magnetic Field Modulation for Enhanced Capture and Distribution of Rare Circulating Tumor Cells. doi:10.1038/srep08745 (2015); Immunomagnetic Assay On-a-Chip Captures, Analyzes Circulating Tumor Cells.