| Modification Notes |
The inter-å trypsin inhibitor (ITI) family is a group of structurally related plasma serine protease inhibitors synthesized in the liver and built up from different combinations of three highly homologous heavy chains (ITI-H1, ITI-H2 and ITI-H3) and one light chain (Bikunin). Another member of the ITI family, ITI-H4 (also known as I a IH4P) harbors a Pro-rich region (PRR) in its C-terminus. ITI is a glycoprotein composed of three polypeptides linked by chondroitin sulphate: two heavy chains, ITI-H1 and ITI-H2, and Bikunin. Bikunin confers the protease-inhibitor function of ITI. The heavy chains of the ITI family, designated as SHAPs (for serum-derived hyaluronan-associated proteins), bind covalently to hyaluronic acid (HA), resulting in pericellular matrix stabilization. Although ITI-H1, ITI-H3 and Bikunin have antitumoral and antimetastatic properties in the cell, these proteins are also associated with malignant transformation of lung tissue. ITI-H3 and Bikunin associate to form pre-å-trypsin inhibitor (PåI), a serine-proteinase inhibitor found in human serum. ITI-H3 mRNA levels increase in response to IL-6. |
