Human inter-alpha-trypsin inhibitor and immunologically related inhibitors investigated by quantitative immunoelectrophoresis. II. Pathological conditions.

Inter-alpha-trypsin inhibitor (I alpha I) and the immunologically related prealbumin-like-migrating proteinase inhibitor (pA-PI) were investigated by crossed immunoelectrophoresis in sera from 68 persons with myocardial infarction, neoplastic diseases, inflammatory diseases, collagenosis, cirrhosis of the liver or uremia. The concentration of pA-PI in serum increased during each of these diseases (p less than 0.01). The concentration of I alpha I was significantly decreased in patients with cirrhosis (p less than 0.01). In day to day studies of a patient with myocardial infarction, a patient with erysipelas and a postoperative patient the concentration of I alpha I was low normal to decreased in the first days of the conditions and increased thereafter to high normal values. A comparison of the concentration of pA-PI with the excretion of the immunologically identical urinary proteinase inhibitor (UPI) showed that the excretion could not be caused by simple overflow of pA-PI in the kidney. The excretion of UPI followed closely the acute-phase-response, as measured by serum C-reactive protein.