Biomarkers

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Biomarkers (biological markers) are measurable characteristics that provide information about what is happening biologically in the body. They may be physiological measurements, such as blood pressure or heart rate; substances measured in blood or other tissues, such as glucose, hormones, proteins, or cytokines; or findings from medical imaging. Researchers and clinicians use biomarkers to help detect or diagnose disease, estimate risk or prognosis, monitor changes over time, and determine how the body responds to treatment.

A biomarker is evidence of a biological process, not necessarily an explanation for it. For example, elevated levels of an inflammatory biomarker may indicate increased inflammatory activity, but the measurement alone cannot tell researchers what caused the inflammation or whether it caused a particular illness. Researchers often examine multiple biomarkers together to better understand complex biological processes.