Inter-alpha-trypsin inhibitor: emergence of a family within the Kunitz-type protease inhibitor superfamily.

Plasma inter-alpha-trypsin inhibitor (I alpha TI) is a major representative of the superfamily of Kunitz-type protease inhibitors in mammals. Formerly, I alpha TI was considered to be a single polypeptide, but recent molecular genetic studies have demonstrated an unexpected multipolypeptide chain structure. The newly discovered genes and gene products form the basis of a new family of I alpha TI-related protease inhibitors.