Intracardiac transplantation of a mixed population of bone marrow cells improves both regional systolic contractility and diastolic relaxation.
BACKGROUND
Pre-clinical and clinical studies suggest that transplantation of bone marrow-derived stem cells can improve global cardiac function. However, no quantitative assessment of regional systolic contraction and correlation with phenotype has been made. Therefore, we used our model of cryoinfarcted rabbit myocardium for intracardiac transplantation of a mixed population of bone marrow-derived cells and assessed both regional function and myogenic conversion of the cells.


METHODS
Nineteen New Zealand white rabbits underwent cryoinjury of the left ventricle. Autologous bone marrow (BM) cells were expanded in vitro. After 2 weeks, either 1 x 10(8) mixed BM-derived progenitor cells (BM group, n = 11) or vehicle (control group, n = 8) were injected into the cryoinjured region. Regional systolic function was measured using micromanometry and sonomicrometry before and 4 weeks after cell injection; cell phenotype was evaluated histologically.


RESULTS
All animals in the BM group significantly improved both systolic shortening (0.11 +/- 0.7 vs -0.05 +/- 0.05 mm in the control group, p < 0.05) and regional stroke work when compared with control (9.6 +/- 2.4 vs -1.2 +/- 1.2 mm . mm Hg, p < 0.003). In addition, the BM group had improved global diastolic function, as measured by minimum dP/dt and end-diastolic pressure. On histologic assessment, BM cells differentiated toward a myogenic phenotype.


CONCLUSIONS
Transplanting a mixed population of marrow-derived cells that can adopt a myogenic phenotype improves regional contractility and diastolic relaxation after myocardial infarction.
Thompson
Richard B
RB
Department of Surgery, Duke University Medical Center, Durham, NC, USA.
van den Bos
Ewout J
EJ
Davis
Bryce H
BH
Morimoto
Yoshihisa
Y
Craig
Damian
D
Sutton
Brad S
BS
Glower
Donald D
DD
Taylor
Doris A
DA
D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology*; D016026:Bone Marrow Transplantation; D002454:Cell Differentiation; D002478:Cells, Cultured; D004195:Disease Models, Animal; D016027:Heart Transplantation; D006352:Heart Ventricles / Q000166:cytology / Q000473:pathology; D045164:Mesenchymal Stem Cell Transplantation; D009200:Myocardial Contraction; D009203:Myocardial Infarction / Q000601:surgery*; D009206:Myocardium / Q000166:cytology*; D010641:Phenotype; D011817:Rabbits; D013318:Stroke Volume