The acute phase reaction

The acute phase reaction is the body's first-line inflammatory defence system, functioning without specificity and memory, in front of, and in parallel with, the adaptive immune system. CRP is a major acute phase protein acting mainly through Ca2+-dependent binding to, and clearance of, different target molecules in microbes, cell debris and cell nuclear material. In an acute phase reaction there may be a more than 1000-fold increase in the serum concentration of CRP. CRP is regarded as an important member of the family of acute phase proteins, having evolved almost unchanged from primitive to advanced species.