title: High number of transplanted stem cells improves myocardial recovery after AMI in a porcine model.
abstract: OBJECTIVE
  The clinical data considering the bone marrow mononuclear cell (BMMNC) therapy in treatment for acute myocardial infarction (AMI) are controversial and the mechanisms remain unknown. Our objective was to study the cardiac function and changes in cytokine levels after administration of BMMNC in experimental AMI model.
  
  
  METHODS
  Unlabeled or Super-Paramagnetic-Iron-Oxide-labeled BMMNCs or saline was injected into myocardium of 31 pigs after circumflex artery occlusion. Ejection fraction (EF) was measured preoperatively, postoperatively and at 21 days by echocardiography. Cardiac MRI was performed postoperatively and after 21 days in 7 BMMNC animals. Serum cytokine levels were measured at baseline, 24 h and 21 days. Cellular homing was evaluated comparing MRI and histology.
  
  
  RESULTS
  From baseline to 21 days EF decreased less in BMMNC group (EF mean control -19 SD 12 vs. BMMNC -4 SD 15 percentage points p = 0.02). Cytokine concentrations showed high variability between the animals. MRI correlated with histology in cell detection and revealed BMMNCs in the infarction area. By MRI, EF improved 11 percentage points. The improvement in EF was associated with the number of transplanted BMMNCs detected in the myocardium.
  
  
  CONCLUSIONS
  BMMNC injection after AMI improved cardiac function. Quantity of transplanted BMMNCs correlated with the improvement in cardiac function after AMI.
authors.affiliation: Department of Surgery, Clinical Research Center, Oulu University Hospital, Oulu, Finland and Department of Surgery, Institute of Clinical Medicine, University of Oulu , Oulu , Finland.
authors.forename: Kirsi
authors.initials: K
authors.lastname: Alestalo
authors.forename: Riikka
authors.initials: R
authors.lastname: Korpi
authors.forename: Jussi
authors.initials: J
authors.lastname: Mäkelä
authors.forename: Siri
authors.initials: S
authors.lastname: Lehtonen
authors.forename: Tuomas
authors.initials: T
authors.lastname: Mäkelä
authors.forename: Fredrik
authors.initials: F
authors.lastname: Yannopoulos
authors.forename: Kari
authors.initials: K
authors.lastname: Ylitalo
authors.forename: Marianne
authors.initials: M
authors.lastname: Haapea
authors.forename: Tatu
authors.initials: T
authors.lastname: Juvonen
authors.forename: Vesa
authors.initials: V
authors.lastname: Anttila
authors.forename: Elisa
authors.initials: E
authors.lastname: Lappi-Blanco
authors.forename: Roberto
authors.initials: R
authors.lastname: Blanco Sequeiros
authors.forename: Petri
authors.initials: P
authors.lastname: Lehenkari
mesh_terms: D000818:Animals; D016026:Bone Marrow Transplantation; D004195:Disease Models, Animal; D008279:Magnetic Resonance Imaging; D009203:Myocardial Infarction / Q000628:therapy*; D009206:Myocardium / Q000473:pathology; D033581:Stem Cell Transplantation; D013318:Stroke Volume; D013552:Swine
keywords: cell targeting; cytokine; ejection fraction; myocardial infarction; stem cell; stem cell transplantation