Posts Tagged: hypoplastic left heart syndrome

Cell Therapy Trials in Congenital Heart Disease

Cell Therapy Trials in Congenital Heart Disease

Hidemasa Oh

Preclinical study of intracoronary cardiosphere-derived cell (CDC) infusion in a rat model of right heart failure. A–K, Pulmonary artery (PA) banding was created to induce pressure overload right heart failure in rats (weighing 250–300 g). The left thorax was opened to expose the pulmonary artery. A silk suture was tied tightly around an 18-gauge needle alongside the pulmonary artery, followed by a rapid removal of the needle to leave the pulmonary artery constricted in the lumen equal to the diameter of the needle. Intracoronary infusion was performed 4 weeks after pulmonary artery banding. The ascending aorta and the pulmonary artery were occluded with a snare twice for a 20-s interval, 10 min apart, during which time rats received an infusion of CDCs or vehicle into the aortic root directly. Animals were euthanized at 4 weeks after treatment to obtain immuno-histological data. Masson-trichrome staining and hematoxylin and eosin (H&E) staining are shown. One month after pulmonary artery banding, significant right ventricular hypertrophy and fibrosis were observed. Note that CDC treatment reduced cardiac fibrosis, but not hypertrophy, one month after infusion (F and I). Bars, 2 mm in A to C; 20 μm in D to I. J, Animals were separated into 4 groups: (1) sham-operated animals (n=12), (2) rats subjected to pulmonary artery banding for 4 weeks with vehicle treatment (n=12), and (3 and 4) rats subjected to banding for 4 weeks with 2 doses of CDC infusion (0.5×105 or 1×105 cells: n=12 in each). Cardiac fibrosis induced by right ventricle pressure overload was measured. CDC infusion significantly reduced the fibrotic area in a cell dose-dependent manner. K, CDC treatment did not affect the diameter of myocytes, which are mechanically enlarged by pressure overload. L, Rat CDCs were infected by lentiviral vectors harboring human cytomegalovirus promoter-driven LacZ reporter gene and were subjected to intracoronary transfer into rats 4 weeks after pulmonary artery banding. Clear CDC engraftment could be detected along the endocardium and surrounding capillary vessels where the cells had been injected. M, Cardiomyocytes were stained with α-sarcomeric actin (red). Newly regenerated LacZ-positive cardiac muscle cells could be detected by β-galactosidase staining (green). Substantial cardiomyocyte regeneration was verified 4 weeks after CDC delivery. Bars, 50 μm. N, Engrafted LacZ-positive CDCs were evaluated by X-gal staining and corrected by the number of total nuclei appreciated within the respective area. Fibrotic and nonfibrotic areas were determined by Masson-trichrome staining derived from serial sections. O, Differentiated cardiomyocytes after CDC infusion were verified by the cells coexpressing both α-sarcomeric actin (red) and β-galactosidase (LacZ, green). The frequency of the cells coexpressing α-sarcomeric actin among the β-galactosidase–positive cells is shown. Data are expressed as the means (SD). [Powerpoint File]