Development of a Rare Cell Fractionation Device: Application for Cancer Detection

Abstract

Isolating rare cells from biological fluids including whole blood or bone marrow is an interesting biological problem. Characterization of a few metastatic cells from cancer patients for further study is desirable for prognosis/diagnosis. Traditional methods have not proven adequate, due to the compositional complexity of blood, with its large numbers of cell types. To separate individual cells based on their mechanical characteristics, we have developed a series of massively parallel microfabricated sieving device. These devices were constructed with four successively narrower regions of channels numbering approximately 1800 per region. As cells traversed the device, they encountered each region and stopped at a gap width that prohibited passage due to their size. Cultured neuroblastoma cells, when mixed with whole blood and applied to the device, were retained in the 10-microm-wide by 20-microm-deep channels. All other cells migrated to the output. A derivative of the same device was utilized to characterize migration of whole blood. Adult white blood cells were retained at the 2.5-microm-wide by 5-microm-deep channels, while red blood cells passed through these channels. Devices designed to capture rare cells in peripheral circulation for downstream analysis will provide an important tool for diagnosis and treatment.

Circulating Tumor Cells: A Review of Non–EpCAM-Based Approaches for Cell Enrichment and Isolation

“…The past decade has seen many new technologies proposed for biological cell sorting and analysis on microchips. Arrays with pillars of varying geometries have been used to fractionate cells in blood and capture tumor cells (37 ). Similarly, crescent-shaped trap arrays with a fixed 5-m gap width within microfluidic chambers have been used to enrich CTCs from whole blood without preprocessing (38 ).…”

Tumor-derived microvesicles: shedding light on novel microenvironment modulators and prospective cancer biomarkers

“…The desire to generate isolation systems that are more readily amenable to diagnostic use has led to a growth in the design of microfluidic, lab-on-a-chip type systems capable of separating and capturing particles of different sizes. Many techniques have been developed using microfluidics to separate microparticles, using methods such as a combination of centrifugal force and graduated mechanical gap (Maruyama et al 2010), flow splitting and recombining (so-called biomimetic devices that rely on size-based variations in particle behavior when in laminar flow) (Takagi et al 2005;Yamada and Seki 2006;Andersen et al 2009); optical fractionation (MacDonald et al 2003;Ladavac et al 2004;Milne et al 2007;Smith et al 2007), or deterministic lateral displacement arrays, which function much like a particle sieve (Huang et al 2004;Mohamed et al 2004;Loutherback et al 2010). Research has also demonstrated that it is possible to isolate shed microvesicles from the cells of origin based on size discrimination using dielectrophoretic sorting.…”

Deterministic hydrodynamics: Taking blood apart

“…However, they typically require additional labels. Size, without labels, has also been used to isolate rare blood components by using filter-based methods (6). The removed component may be harvested by periodically stopping the flow into the filter and flushing to remove the desired particles from the filter mesh.…”