Page "Haptoglobin" Paragraph 0

Haptoglobin ( abbreviated as Hp ) is a protein that in humans is encoded by the HP gene.

In blood plasma, haptoglobin binds free hemoglobin ( Hb ) released from erythrocytes with high affinity and thereby inhibits its oxidative activity.

The haptoglobin-hemoglobin complex will then be removed by the reticuloendothelial system ( mostly the spleen ).

In clinical settings, the haptoglobulin assay is used to screen for and monitor intravascular.

In intravascular hemolysis free hemoglobin will be released into circulation and hence haptoglobin will bind the Hb.

This causes a decline in Hp levels.

Conversely, in extravascular hemolysis the reticuloendothelial system, especially splenic monocytes, phagocytose the erythrocytes and hemoglobin is not released into circulation ; serum haptoglobin levels are therefore normal.