A microfluidic device has been created that can harvest rare circulating tumor cells (CTCs) from blood to enable their expansion in culture for analysis.

This novel approach for capturing and culturing CTCs combines micromagnetics and microfluidics within a cell-separation device, about the size of a credit card, in which microfluidic channels have been molded into a hard clear polymer.

The devise was created by collaborating scientists at the Wyss Institute (Boston, MA, USA) and Children's Hospital Boston (MA, USA). As blood flows through the channels in the appliance, magnetic microbeads that have been coated using epithelial cell adhesion molecule (EpCAM) antibody selectively stick to the CTCs and are used to separate them from the other cells in the blood. The dimensions of the channels have been designed to protect CTCs from mechanical stresses that might alter their structure or biochemistry, as well as to maximize the number of CTCs that can be captured. The high sensitivity visualization capabilities of the device also allowed detection of a single cell within one of its dead-end side chambers.

The approach demonstrated extremely high efficiency by capturing more than 90% of CTCs from the blood of mice with breast cancer. Of particular significance was the fact that the captured CTCs were able to be grown and expanded in culture. These intact living tumor cells could be used for additional testing and molecular analysis, for example, in screening drugs to meet the personal needs of individual patients in the future. Further testing found that the device is sensitive enough to detect the sudden increases in the number of CTCs that signal a cancer's metastatic transition and could therefore alert clinicians to possible disease progression.

The team carried out their studies with one common type of breast cancer. The same device could be used to address a wide range of tumor types as well as applications beyond cancer, such as collecting circulating stem cells or endothelial progenitor cells from the blood and growing them for use in organ repair, in the future. The study was published on March 8, 2012, in the online journal Lab on a Chip.


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Wyss Institute

Children's Hospital Boston