ITIH4

The inter-alpha-trypsin inhibitor heavy chain (ITIH4), also known as IHRP (inter-alpha-trypsin heavy chain-related protein), PK-120 (plasma kallikrein-sensitive glycoprotein 120), or Gp120 (glycoprotein 120), is a cell surface protein that belongs to the ITIH family. ITIH4 is a N-glycosylated Type II acute phase protein. It is secreted into the blood, where it undergoes proteolysis and is cleaved by plasma kallikrein into two smaller forms.

Expression of ITIH4 has been detected only in liver, and it seems to be upregulated in response to trauma such as ischemic stroke or myocardial infarction. ITIH4 is documented to function as a trypsin inhibitor. In the meantime, it may also be involved in acute phase reactions.

Entrez Gene ID: 3700
UniProt ID: Q14624