Biomarkers: nature's alarm
Biomarkers are markers of a biological nature: substances or phenomena produced or displayed by the body in anticipation of, or during a state of disease. They are useful to scientists as we can develop objective ways to identify and measure these to aid with diagnosis and treatment.
Procalcitonin
Procalcitonin (PCT) is a protein not normally found in the bloodstream of healthy individuals. The opposite is true during times of serious biological stress, when it is produced by C-cells in the thyroid gland from pre-procalcitonin. This results in an accumulation in the blood for reasons not currently understood- normally, cleavage into 3 distinct parts produces the hormone calcitonin, hence the designation prohormone (hormonal precursor).
Contemporary research has identified that sepsis is one of the aforementioned stressors, meaning that procalcitonin can act as a potent biomarker. Studies have successfully demonstrated that it can be used to diagnose sepsis- however, they have a few problems. Firstly, the techniques used had to be performed in specialist laboratories by trained biochemists. Secondly, the screening process was time-consuming, and time is not a luxury that sepsis affords patients. Finally, the tests had a reasonably high specificity (ability to identify patients without sepsis) and sensitivity (ability to identify septic patients), but these figures weren't high enough (below recommended 95%). Procalcitonin screening in isolation cannot be relied on to diagnose sepsis in a clinical environment.
sTREM-1
sTREM-1 is the soluble variant of a receptor TREM-1, or triggering receptor expressed on myeloid cells 1. Normally found on the surface of immune cells such as monocytes and neutrophils, this structure is responsible for activation of their immune function, contributing to processes such as inflammation. The soluble variant can be detected at high levels in the bloodstream during sepsis, possibly due to its ability to amplify the inflammatory response, meaning studies focusing on its use as a biomarker for this purpose has had some success. Per contra, as with PCT above, tests for elevated blood levels in isolation have not shown requisite sensitivity and specificity for routine clinical use. They also require specialist equipment with trained bio-scientists to perform.
Therasis: innovation, one patient at a time
Clearly, there is a need for a rapid; repeatable; accurate; cheap; and easy test for sepsis to help doctors diagnose patients early, monitor their progress, and increase survival rates. The answer? After 10 years of research from Therasis, SepDetect. Click the tabs above to explore what our technology can do for you.