Inclusion Criteria:

Patients with acute coronary syndrome (ST-depression in at least 2 leads > 0,1 mV), or T-wave inversion, with or without elevated myocardial biomarkers (Troponin T oder I), together with typical clinical presentation), treated as follows:

• Acute percutaneous revascularization with stent implantation within 48 hours after symptom onset.
• Successful acute PCI (residual stenosis < 30%, TIMI flow > 2).
• Hemodynamic stability
• Age 18 - 80 years
• Written informed consent
• Active contraception in women of childbearing age

Exclusion Criteria:

• Patients with STEMI (ST elevation in 2 leads above 0,2 mV in lead V1, V2 oder V3 or above 0,1 mV in the other leads)
• Necessity of additional PCI in non-infarct vessel at the time of study therapy (multi-vessel PCI in the acute event is possible)
• Heart failure (LVEF ≤ 30 %).
• Arteriovenous malformation or aneurysms
• Active infection (C-reactive protein > 10 mg/dl), or fever, or diarrhoea within the last 4 weeks
• Chronic inflammatory disease
• HIV infection or active hepatitis
• Neoplastic disease without documented complete remission within the last 5 years
• Recent stroke within the last 3 months
• Impaired kidney function (creatinin > 2,5 mg/dl) at the time of treatment
• Significant liver disease (GOT > 2x upper normal value or spontaneous INR > 1,5.
• Hematopoetic disease (anaemia with Hb< 8.5 mg/dl; thrombocytopenia < 100.000/µl; splenomegaly
• Known allergies to Clopidogrel, Heparin or Abciximab
• History of bleeding disorder
• GI bleeding within the last 3 months
• Major surgery or trauma within the last 2 months
• Uncontrolled hypertension
• Pregnancy
• Mental disability
• Previous progenitor cell therapy
• Participation in a different clinical trial within the last 30 days