INCREASED SERUM ALPHA(1)-ANTICHYMOTRYPSIN IN PATIENTS WITH PROBABLE ALZHEIMERS-DISEASE - AN ACUTE-PHASE REACTANT WITHOUT THE PERIPHERAL ACUTE-PHASE RESPONSE

Serum levels of alpha(1)-antichymotrypsin (alpha(1)-ACT) were measured in patients with early and late onset Alzheimer's disease (e-AD, I-AD), patients with vascular dementia (VD) and healthy elderly. Patients with I-AD were divided into two groups, one had normal alpha(1)-ACT values and one had increased serum levels of alpha(1)-ACT. Other acute phase proteins were also measured. The serum levels of alpha(2)-macroglobulin (alpha(2)-MG), alpha(1)-antitrypsin (alpha(1)-AT), ceruloplasmin (CER), transferrin (TRSF) and alpha(1)-acid glycoprotein (alpha(1)-ac.GL) were within the normal range. The C reactive protein (CRP) was occasionally detectable at low concentrations in e-AD, in both groups of I-AD patients and in VD patients. Low serum concentrations of interleukin-6 (IL-6) were found in a higher proportion of I-AD than in patients with e-AD or VD. These results indicated that increased levels of alpha(1)-ACT along with occasional detection of IL-6 might be peripheral markers of the 'acute reaction' in the brain.