Abstract
Background:
Clinical trials have shown a sustained beneficial effect of bone marrow mesenchymal stem cells (MSCs) as a therapy for acute and chronic heart failure (HF). Clinical grade cell manufacturing of autologous and allogeneic MSCs is becoming a standard procedure. This study investigates the differences of bone marrow MSC isolation and expansion in favorable in vitro conditions. We compared MSC production from both healthy young donors and chronic HF patients.
Methods:
We analyzed MSC manufacturing records from five clinical trials: TAC-HFT (Ischemic cardiomyopathy (CMP), patient and donors), POSEIDON (Ischemic CMP, donors), POSEIDON DCM (Dilated CMP, donors), TRIDENT (Ischemic CMP, donors), and CRATUS (Frailty, donors).
Results:
All cells expressed CD105, CD90 and lacked hematopoietic marker CD45. The age of healthy donors (25.5 ± 0.7 y.o., N=24) and HF patients (56.1 ± 2.5, y.o., N=23), was significantly different (P<0.0001). Collectively, the number of mononuclear cells (MNCs) isolated from bone marrow (volume range 58-125ml) didn’t differ between the groups. However, plated MNCs from healthy adults generated more MSCs than MNCs from HF patients (p0: 5.9x10^6±0.5x10^6, N=23 vs 3.8x10^6±0.4x10^6, N=24, respectively, P=0.003 and p1: 15.4x10^6±2.5x10^6, N=23 vs 10.8x10^6±1.1x10^6, N=24, respectively, P=0.036). No correlation was found between stem cell growth and age (35 to 78y.o.). Left ventricular ejection fraction (LVEF) in patients with HF had a direct correlation with MSC growth rate (P=0.03), particularly, in patients with severely depressed LVEF (<30%), which had a tendency to generate less MSCs overall. Moreover, MSCs from HF patients demonstrated less migration compared to MSCs from healthy donors at 6, 10 and 24 hours (h) relative to baseline (6 h: 9.5±3.0% vs 30.7±2.1%; 10 h: 19.9±13.7% vs 53.1±2.5% and 24 h: 41.5±15.8% vs 88.9±1.6%, N=4, respectively. P=0.03).
Conclusions:
Despite equivalent numbers of MNCs, healthy young donors generate significantly more MSCs than HF patients, due to increased growth rate and higher number of resident stromal bone marrow stem cells. MSC migration was impaired in HF patients compared to healthy donors. HF appears to be an independent factor for MSC renewal capacity and culture phenotype.