Cell Surface Marker: Some protein or receptor sticking out of the cell membrane. I explain this more in depth in my immunocapture post.
CTC: Circulating tumor cell. Read about what they are and why they’re important here.
Microemboli: A small mass of cells or tissue inside the bloodstream.
Platelets: aka thrombocytes, important in the formation of blood clots.
Phenotype: Observable characteristics of a cell.
RBCs: Red blood cells, aka erythrocytes.
Senescence: When a cell hits the Hayflick limit and can no longer divide naturally.
WBCs: White blood cells, aka leukocytes.
Benchmarking is critical for assessing CTC isolation tech performance
In my “How to Sort CTCs” series, I covered a variety of sorting methodologies used for patient prognosis. However, before clinical implementation, it is important characterize device performance with a series of standards. This is impossible to do with a patient blood sample, because there is an unknown number of CTCs floating around with other blood cells, which can be effected by the cancer treatment process (e.g. radiation patients often have anemia)1. Furthermore, this is all changing dynamically as a function of both time and treatment.
For this reason, engineers need an alternative system that can serve as a patient blood model, but it is repeatable and controllable. Immortalized cancer cell lines—derived from cancers of various organs—are commonly used for this purpose. A normal human cell can only divide a set number of times before it undergoes senescence; this is called the Hayflick limit. Immortalized cell lines have been genetically altered to surpass the Hayflick limit and continue dividing indefinitely.
This enables researchers to create standardized systems to benchmark their technology with. A known number of cancer cells can be spiked in varying ratios with different blood components, allowing for measurement of sensitivity and specificity of capture, along with other metrics. For this reason…