- A plasma protein produced mainly by the liver.
- Also an acute phase protein - and so rises in inflammatory conditions.
- Binds to free haemoglobin in the blood, preventing oxidative damage. The resulting haemoglobin-haptoglobin complex that is scavanged by the reticulo-endothelial system. Haemolysis releases free haemoglobin, which reduces the level of haptoglobin.