Differential increase of CD34, KDR/CD34, CD133/CD34 and CD117/CD34 positive cells in peripheral blood of patients with acute myocardial infarction

Objective Circulating progenitor cells (CPC) may contribute to cardiac regeneration and neovascularization after acute myocardial infarction (AMI). For potential therapeutic use, understanding the endogenous mechanisms after ischemia is inevitable. We investigated the absolute number, but also the subset composition of CD34+ CPC after AMI. Methods CD34+, KDR+/ CD34+, CD133+/CD34+ and CD117+/CD34+ CPC were analyzed by FACS in peripheral blood of 10 patients with acute MI (59 +/- 5 yrs, m/f=8/2) at day of AMI (day 0) and days 1-5. For comparison patients with stable coronary artery disease (CAD, n=12, 66 +/- 2 yrs, m/f=10/2) and young healthy volunteers (n=7, 26 +/- 2 yrs, m/f=3/4) were studied. Results CD34 and KDR/CD34, CD133/CD34, CD117/CD34 were increased day 3 and 4 after AMI. KDR+ fraction within CD34+ population remained unchanged (58.3 +/- 7.8% vs 55.3 +/- 10.6%), whereas CD133+ (64.9 +/- 3.1% vs 43.5 +/- 5.9%, P=0.006) and CD117+ fractions (71.7 +/- 5.6% vs 50.1 +/- 5.5%, P=0.02) were elevated. In CAD, all CPC and fractions were similar as AMI day 0. Healthy volunteers had more CD34+ than CAD and AMI day 0. Double positive CPC were also higher, but fractions were unchanged vs CAD with more KDR/CD34 in trend (72.8 +/- 10.6% vs 50.5 +/- 5.6%, P=0.058). After AMI both absolute numbers of CD34+ and their subset composition change, suggesting selective mobilization of CPC. Increased CPC after AMI never reach numbers of young healthy volunteers.