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The History of hs-CRP

C-reactive protein was first discovered in 1930 by researchers William Tillett and Thomas Francis Jr. at the Rockefeller Institute, who noticed that blood serum from pneumonia patients reacted strongly with a specific bacterial polysaccharide, leading them to name the newly identified substance after that very reaction. For decades, CRP was measured only using standard assays sensitive enough to detect the dramatic elevations seen during acute infection or inflammation, but far too crude to reliably distinguish the much subtler, low-grade elevations relevant to everyday cardiovascular risk. That changed substantially in the 1990s and 2000s, when cardiologist Paul Ridker led landmark studies, including the influential JUPITER trial published in 2008, demonstrating that a new high-sensitivity CRP assay could meaningfully identify seemingly healthy people at genuinely elevated risk for future heart attacks and strokes down the road.

What hs-CRP Actually Is

hs-CRP measures the exact same C-reactive protein molecule as standard CRP testing, but using a considerably more sensitive laboratory technique capable of accurately detecting the low-level chronic inflammation now understood to quietly contribute to atherosclerosis and cardiovascular disease over many years. The liver produces CRP in direct response to interleukin-6 and other inflammatory signaling molecules released throughout the body, meaning hs-CRP levels rise whenever ongoing inflammation is present anywhere, whether from infection, autoimmune disease, or the slow, silent inflammatory processes occurring within blood vessel walls themselves. Because hs-CRP is nonspecific, doctors interpret it carefully alongside a patient's broader cardiovascular risk profile rather than treating it as a standalone diagnosis of any single, specific medical condition on its own.

How hs-CRP Is Measured

hs-CRP is measured from a standard blood draw using highly sensitive immunoassay techniques, typically nephelometry or turbidimetric methods, in which antibodies bind specifically to CRP molecules and the resulting light scattering or absorbance is measured with far greater precision than older, conventional CRP assays ever allowed. This enhanced sensitivity allows laboratories to reliably distinguish meaningful differences within the low concentration range relevant to cardiovascular risk stratification, a level of precision that simply wasn't achievable with the original assays first developed decades earlier for detecting acute infection alone. Because CRP can spike temporarily from a cold, minor injury, or recent vaccination, doctors typically recommend repeating an elevated hs-CRP result on a separate, genuinely healthy day before drawing any firm long-term cardiovascular conclusions.

Scientists Behind the Science

William Tillett and Thomas Francis Jr. deserve lasting credit for their foundational 1930 discovery, identifying an entirely new blood protein decades before anyone could have anticipated its eventual relevance to heart disease rather than just infectious illness. Paul Ridker's extensive body of cardiovascular research decades later fundamentally transformed CRP from a simple marker of infection and inflammation into a genuinely validated tool for predicting future heart attack and stroke risk in seemingly healthy people. Together, their combined work, separated by roughly seven decades of steady scientific progress, gave modern cardiology one of its most widely used inflammatory biomarkers for identifying hidden cardiovascular risk that traditional cholesterol testing alone often misses entirely.