Mesenchymal Stromal Cells from Patients with Cyanotic Congenital Heart Disease are Optimal Candidate for Cardiac Tissue Engineering.

Engineered heart tissues (EHTs) are regarded as being the most promising alternative to synthetic materials, and autologous mesenchymal stem cells (MSCs) are widely used as seeding cells. However, few studies have evaluated the feasibility of using MSCs from patients with cyanotic congenital heart disease (C-CHD) as seeding cells for EHTs, in comparison with cells from patients of acyanotic congenital heart disease (A-CHD). In the present study, we cultured MSCs from A-CHD and C-CHD patients in normoxia or hypoxia conditions, and compared their pro-angiogenic, anti-apoptotic and inflammation-modulatory potentials. In vivo, we seeded the cells into collagen patches conjugated with, or without, proangiogenic cytokines, which were used to repair the right ventricular outflow tract (RVOT) of rats. The in vitro results showed that C-CHD MSCs expressed higher levels of VEGFA and VEGFR2, and secreted more pro-angiogenic and anti-inflammatory cytokines under hypoxic conditions. On the other hand, apoptosis-related genes from C-CHD MSCs were modulated adaptably, converting these cells into an anti-apoptotic phenotype. In vivo studies demonstrated that in 4 weeks after RVOT reconstruction, cytokine-immobilized patches seeded with C-CHD MSCs exhibited preserved morphology, prolonged cell survival and enhanced angiogenesis compared to A-CHD MSCs. C-CHD MSCs that undergo "naturally hypoxic precondition" present a better cell source for EHTs, which would provide a promising individualized biomaterial for C-CHD patients.

Improved Left Ventricular Aneurysm Repair with Cell- and Cytokine-Seeded Collagen Patches.

BACKGROUND: Engineered heart tissues (EHTs) present a promising alternative to current materials for surgical ventricular restoration (SVR); however, the clinical application remains limited by inadequate vascularization postimplantation. Moreover, a suitable and economic animal model for primary screening is another important issue. METHODS: Recently, we used 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride chemistry (EDC) to initiate a strengthened, cytokine-conjugated collagenous platform with a controlled degradation speed. In vitro, the biomaterial exhibited an enhanced mechanical strength maintaining a porous ultrastructure, and the constant release of cytokines promoted the proliferation of seeded human mesenchymal stem cells (hMSCs). In vivo, with the hMSC-seeded, cytokine-immobilized patch (MSCs + GF patch), we performed modified SVR for rats with left ventricular aneurysm postmyocardial infarction (MI). Overall, the rats that underwent modified SVR lost less blood and had lower mortality. After 4 weeks, the rats repaired with this cell-seeded, cytokine-immobilized patch presented preserved cardiac function, beneficial morphology, enhanced cell infiltration, and functional vessel formation compared with the cytokine-free (MSC patch), cell-free (GF patch), or blank controls (EDC patch). Furthermore, the degradable period of the collagen patch in vivo extended up to 3 months after EDC treatment. CONCLUSIONS: EDC may substantially modify collagen scaffold and provide a promising and practical biomaterial for SVR.