1. Intravenously Delivered Mesenchymal Stem Cells:
a transformative strategy for cardiac stem cell therapeutics
Stephen E. Epstein, MD
Dror Luger, PhD
Michael J Lipinski MD
MedStar Heart and Vascular Institute
Washington Hospital Center

2. Stephen Epstein, MD I have a relevant financial relationship:
I have a relevant financial relationship:
Conflict of Interest
Chairman, Scientific Advisory Committee, CardioCell
Equity holder in CardioCell, LLC

3. Cellular and cytokine response to AMI

4. Progressive deterioration in LV function and adverse remodeling post AMI
(murine AMI model)
LVEF **
LVEDV
LVESV

5. Cellular and cytokine response to AMI
Hypothesis:
The inflammatory responses of some patients are excessive and persistent, leading to progressive inflammation-induced myocardial dysfunction.

6. Evidence that inflammation plays an important role in the progressive decrease in LV function occurring following AMI…

7. Effects of AMI on NK cells in the spleen and myocardium.
Splenic NK cells (%)
P<0.001
P=0.048
P=0.045
NK cells in the Spleen
7 days post AMI
AMI increases NK cells in the spleen and myocardium.
NK cells are major orchestrators of inflammation, having effects on many cellular players involved in inflammation.
Luger, Lipinski, Epstein et al. 2017

8. If inflammation plays a key causal role in the progressive myocardial dysfunction that occurs following AMI, then decreasing NK cells—a key marker of inflammation—should prevent the progressive myocardial dysfunction…

9. Effects of NK cell depletion (via an anti NK cell antibody) on LV infarct size, LV function, and adverse remodeling A
LV Infarct (%)
Control
NK Depletion B
Ejection Fraction (%)
Baseline
Day 7
Day 20 C D
NK cell depletion decreases infarct size and improves both LV function and adverse remodeling.

10. Pathways by which persistent inflammation causes
progressive functional deterioration of the myocardium in patients with AMI or with cardiomyopathy
Increased interstitial collagen deposition
ROS
microvascular-induced
ischemia
Microvascular
dysfunction
Parenchyma loss
Apoptosis
replacement fibrosis
Inflammatory and immune responses
Matrix metalloproteinases
Heart Failure
reactive fibrosis
Decreased energy availability
Progressive parenchyma
Dysfunctional
parenchyma
Mitochondrial dysfunction

11. Implications of the concept that inflammation contributes to progressive myocardial dysfunction…

12. Immunomodulatory activities of MSCs
Aggarwal S, Pittenger MF. Blood Feb 15;105(4):

13. The prevailing view of stem cell-mediated mechanisms responsible for cardiac benefit = local myocardial effects:
The cells engraft in damaged myocardium, then either–
transdifferentiate into functional myocardium,
stimulate resident myocardial stem cells to expand, or
secrete substances leading to myocardial healing.
This perspective implies that the greater the number of engrafted cells in the myocardium the greater the cardiac benefit.
Because only a small percentage of intravenously administered stem cells engraft in the myocardium, invasive catheter-based strategies have been uniformly adopted (intracoronary or transendocardial injection).

14. Given that MSCs secrete, through paracrine mechanisms, multiple cytokines that have anti-inflammatory activities…could the intravenous administration of MSCs, through systemic anti-inflammatory effects, improve cardiac outcomes post AMI and in ischemic CM?

15. IV administered MSCs decrease NK cells in the spleen
Splenic NK cells (%)
NK cells in the Spleen
P<0.001
P=0.048
P=0.045
7 days post AMI

16. IV administered MSCs decrease neutrophils in the heart
Naïve MI MI+MSCs
7 days post AMI
Heart Neutrophils (%)
Neutrophils
Neutrophils are immediate responders to injury and contribute importantly to adverse myocardial remodeling post MI.

17. IV administered MSCs improve LV function following AMI
= Control
= MSC treated
Intravenously administered MSCs improve, but not significantly, LV function and adverse remodeling post AMI.

18. Hypothesis: MSCs improve LV outcomes, but only in mice with marked LV dysfunction caused by large infarcts.

19. Acute Myocardial Infarction:
Effects of MSCs in small vs. large infarcts
21 days post AMI 40 20 60
Ejection Fraction (%)
at Day 20
<25% ≥25%
Control
<25% ≥25% MSC-treated
Infarct size
Pre-Infarct
value
P=0.10
P=0.93 EF
P=0.03
P=0.46
End Diastolic Volume (µL)
at Day 20
100 50
150
<25% ≥25%
Control
<25% ≥25% MSC-treated
Infarct size
Pre-Infarct
value
LVEDV
End Systolic Volume (µL)
at Day 20
100 50
150
<25% ≥25%
Control
<25% ≥25% MSC-treated
Infarct size
Pre-Infarct
value
P=0.04
P=0.53
LVESV

20. Mice with Ischemic Cardiomyopathy
= Control
= MSCs

21. CardioCell Phase IIa Clinical Trial
Safety and Preliminary Efficacy of Intravenous Allogeneic MSCs in Patients With Non-ischemic Heart Failure
All subjects
MSCs
Placebo
Day 0
Randomization
Day 90
Crossover
Day 180
Butler J, Epstein SE, Lipinski MJ, Gheorghiade M, et al. Circ Res. 2017;120:

22. Significantly improved six minute walk test,
IV administered MSCs:
Significantly improved six minute walk test,
Significantly improved clinical functional assessment,
Significantly improved NYHA functional class.
In ad-hoc exploratory analyses, there were significant reductions in LVEDV (p=0.04) and LVESV (p=0.02) and increases in LVEF (p=0.02) within the MSC group. No such changes occurred in the placebo group.
Importantly, improvement in LVEF was associated with the number of circulating NK cells…
Butler J, Epstein SE, Lipinski MJ, Gheorghiade M, et al. Circ Res. 2017;120:

23. IV administered MSCs decreased blood NK cells.
The magnitude of NK cell decrease correlated with the magnitude of the increase in LVEF.
The greater the reduction in NK cells produced by IV MSCs, the greater the improvement in LVEF.
Butler J, Epstein SE, Lipinski MJ, Gheorghiade M, et al. Circ Res. 2017;120:

24. Conclusions
IV administered MSCs:
Inhibit progressive myocardial deterioration that occurs following AMI and during chronic heart failure in murine models.
The improved LV outcomes are causally related to potent systemic anti-inflammatory effects.
Improve clinical outcomes and LV function in a Phase IIa clinical study.

25. These data suggest that MSCs, contrary to existing concepts:
Do not have to be delivered directly to the heart to improve cardiac function.
Rather, MSCs, delivered intravenously to patients with AMI or ICM/NICM, by modulating excessive inflammatory responses, may improve cardiac function and patient outcomes.
Thus, invasive delivery procedures can be avoided.
The validity of what could be a transformative concept to the stem cell field awaits the results of pivotal clinical trials.