CD55 (Decay accelerating factor (DAF))

Decay-accelerating factor (DAF), also known as CD55, is a surface protein involved in the regulation of the human complement system. It is a glycoprotein with a molecular mass of about 70 kDa, found on the surface of all circulating blood cells and in various tissues.

Decay accelerating factor (DAF) plays a crucial role in protecting the body's own cells from complement-mediated destruction. It does this by inhibiting the formation of the protein complexes C4b2b and C3bBb (C3-convertases), which are part of the complement system. DAF disassociates Bb from C3b, thereby preventing the splitting of C3 by the convertase. Additionally, DAF increases the degradation rates of the C3 and C5 convertases
…