Abstract

Sized-based rare cells isolation by microfilters

Chia-Pin Chang, Scientist, Institute of Microelectronics A*STAR

A microfilter-contained microfluidic chip has been developed for rare cells isolation. This chip has been used to isolate circulating tumor cells (CTCs) and fetal nucleated red blood cells (FNRBCs). And, it shows great potentials for both applications. Cells shredded from cancer tumor have been reported to be circulating in patients’ blood while fetal cells from the fetus can be found circulating in maternal blood. These findings throw some light to the state of the cancer stricken patients and provide potential prognostic value in treatment. Likewise, the genomic information provided by circulating fetal nucleated red blood cells (FNRBCs) or trophoblastic cells can be used for detection of aneuploidies in early pregnancies and single gene disorders such as cystic fibrosis. The grand challenge in rare cells isolation from whole blood is enriching the sample with target cells and removing the bulk of non-target cells in order to achieve high isolation efficiency of the targeted cells. A polymer-based microfilter membrane-contained microfluidic chip has been developed to overcome this challenge. This microfluidic chip would facilitate the separation, isolation and recovery of target rare cells, including circulating tumor cells (CTCs) and fetal nucleated red blood cells (fNRBCs), from a mixture of white blood cells, red blood cells, platelets and others. We successfully demonstrate this device can recover CTCs from 15 cancer patient samples with 100% sensitivity. In addition, this device can isolate FNRBCs from villi tissue sample with >85% isolation efficiency.