Studies of protease and protease inhibitors in familial amyloidotic polyneuropathy.

Serum levels of 6 protease inhibitors, alpha 1-antitrypsin, Cl inactivator, alpha 2-macroglobulin, antithrombin-3, alpha 1-antichymotrypsin and inter-alpha-trypsin inhibitor were measured in patients with familial amyloidotic polyneuropathy (FAP) and a control group without neurologic disease. No significant differences were observed between the 2 groups. The proteolytic effect of brinase, an enzyme from Aspergillus oryzae, on amyloid tissue sections from patients with FAP was also evaluated. Amyloid fibrils were degraded by brinase, while the tissue structure remained fairly intact.