How do flow
Biopsies work?

The challenge of capturing in flow

A flow biopsy needs to specifically capture the target cells, while leaving the billions of other cells alone. Many microfluidic devices can do this by using immunoaffinity enrichment, in which something unique on the target cells’ surface sticks to a receptor on the coating, for example an antibody. However, the blood flow is way too fast and too turbulent for immunoaffinity enrichment, so specialized technologies are needed to overcome this challenge.

How do we make flow biopsies work?

The four cornerstones of our product.

Micro engineered surface profile

To capture circulating tumor cells in the turbulent and fast blood flow, our flow biopsy tools are outfitted with a unique micro engineered surface profile that can temporarily slow down the cells flowing by. The micro-engineered surface profile also shields the captured cells from the bloodstream and protects them during the extraction of the wire. With millions of new cancer patients every year, every solution needs to be scalable. Therefore, the surface profiles are manufactured by advanced micro-injection molding.

Molecular engineered coating

The blood flows too fast for traditional coatings with antibodies to capture circulating cancer cells in the bloodstream. Our flow biopsy tools are therefore coated with a biomimicking material that is specifically engineered to slow down and capture circulating cancer cells. This unique coating also ensures hemocompatibility, viability of captured circulating tumor cells, and a gentle release for downstream analysis.

Catheter compatibility

Our flow biopsy tools are compatible with central venous catheters that are commonly used to administer chemotherapy. This avoids the need for dedicated venous access and simplifies their use. Using existing central venous catheters offers other advantages too, as not every vein is the same. Cancer cells shed from the tumor into the bloodstream, but most will not circulate for long because the bulky and stiff circulating tumor cells are lost in capillary beds of the lungs and other organs. The unfiltered central venous blood contains the most cancer cells that are the most representative of the tumor, therefore providing a superior sample.

Diagnostic compatibility

The higher the yield and the purity of a sample, the more reliable a diagnostic test. Unlike liquid biopsies, flow biopsies can provide hundreds of circulating tumor cells, providing sufficient DNA, RNA, proteins, or whole cells, for any kind of diagnostic test.

How do flow
biopsies compare?

Tissue biopsies are
reliable but risky

A tissue biopsy extracts a piece of (hopefully) tumor tissue, which can be used to determine the type and stage of cancer. For more advanced treatments, a biopsy is often required to determine the molecular profile of the cancer and predict if that treatment will be effective.

However, a tissue biopsy provides a snapshot of a small section of a single tumor, but cancer cells differ within a tumor, between tumors, and over time. Considering that tissue biopsies are both painful and risky, it is infeasible to perform multiple tissue biopsies. This means that tissue biopsies provide a picture of the cancer that is only temporarily accurate at best.

With increasingly advanced therapeutics and diagnostics, tissue biopsies simply cannot keep up.

Tissue biopsy

Liquid biopsies are
safe but noisy

A liquid biopsy uses a blood sample instead of tumor tissue. Drawing blood is certainly much safer, simpler, and faster than taking a tissue biopsy, and for that reason liquid biopsies have received much attention both clinically and scientifically.

Liquid biopsies have been adopted only recently and moderately. This is not for a lack of effort or investment but due to the inherent limitation of finding a signal in a sea on noise. Circulating tumor cells are so rare that, even when efficiently isolating all of them, a blood sample does not contain enough for a reliable diagnosis. Circulating tumor DNA might be more plentiful, but analyzing it is difficult and is often hampered by biological noise.

Liquid biopsies might be safe but are inherently limited in sensitivity and accuracy.

Liquid biopsy

Flow biopsies provide
a better sample

Instead of drawing a blood sample, flow biopsies use medical wires inserted into the bloodstream to directly collect the cancer cells. A specialized coating captures the circulating cancer cells that flow by, accumulating many more cells over time than would ever be in a single blood sample.

The medical wire is inserted into the bloodstream through existing catheters or cannula’s that are often already in place to administer fluids or chemotherapy. This avoids the need to draw blood or make a surgical incision, which minimizes risks and allows for sampling frequently and pain-free.

Flow biopsies will provide a safer and more reliable alternative to tissue- and liquid biopsies that can be performed as often as the doctor needs.

Flow biopsy

Peripheral venous sampling

Flow biopsies can provide a sample whenever a bioanalyte is too rare to use a blood sample. Some bioanalytes, like bacteria and specific subsets of extracellular vesicles, can be collected from the peripheral blood flow.

Bacteria

Like circulating tumor cells, bacteria are extremely rare in the blood even during bacteremia (a systemic bacterial infection in the blood). It is important to diagnose and treat a bacteremic patient as quickly as possible, but current methods are slow and prone to error.

Our flow biopsy tools can collect large numbers of bacteria from the bloodstream quickly, requiring only a peripheral venous catheter. Our flow biopsy tools also minimize the risk of sample contamination, allow for much faster processing, and avoid the need to repeatedly draw blood. This will save valuable time during the critical stages of septic patients.

Extracellular vesicles

Though generally not considered rare, extracellular vesicles are receiving more and more attention as potential sources of clinically relevant information. The difficulty of efficiently isolating specific extracellular vesicles remains a major bottleneck in the field.

Our flow biopsy tools can collect specific subpopulations of extracellular vesicles and will allow for efficient processing by offering a pure and low volume, high concentration sample.


The right therapy every time, all the time.