Plasma Amyloid-BetaPeptides in Acute Cerebral Ischemia: A Pilot Study

Background Blood-based tests for a rapid and valid diagnosis as well as outcome prognosis of acute stroke are desirable. Recently, plasma A beta 40 was suggested as an independent cerebrovascular risk factor candidate. Methods We investigated eight plasma samples of patients with clinical signs of acute cerebral ischemia for derangements of plasma amyloid-beta (A beta) peptide patterns as compared to 13 patients with other neuropsychiatric diseases. For the analysis of plasma, we used immunoprecipitation followed by the quantitative A beta-SDS-PAGE/immunoblot. Results The major outcome was a striking decrease of A beta 140 in plasma paralleled by an increase in the ratio of A beta 138/A beta 140 in two patients with acute stroke. Interestingly, these patients had an onset of symptoms within only 24 hr before venous puncture and there was a strong correlation of A beta 138/A beta 140 levels with the time span between onset of symptoms and venous puncture. Conclusion From these results, we suggest the ratio of plasma A beta 138/A beta 140 as a possible biomarker for the early diagnosis of acute stroke. J. Clin. Lab. Anal. 26:238-245, 2012. (c) 2012 Wiley Periodicals, Inc.