Clinical Protocol for Angiogenesis by Intramyocardial Injection of Autologous Bone Marrow Mononuclear Cells in Patients With Severe Coronary Artery Disease TACT-NAGOYA-HEART

Stem Cell Smart Technology, where are we now and how far we have to go?

Approximately eight million people in the United States have peripheral arterial disease, which increases exponentially with age. There have been a plethora of available treatments including surgery, angioplasty, atherectomy, laser technology, and cell-based therapies. Cell-based therapies were developed in the hope of translating laboratory-based technology into clinical successes. However, clinical results have been disappointing. Infusion or injection for stem cell therapy is still considered experimental and investigational, and major questions on safety and durability have arisen. In no option patients, how can they be treated safely and successfully? In this article, we review contemporary practice for cell therapy, its pitfalls and breakthroughs, and look at the future ahead. We introduce a novel smart system for minimally invasive delivery of cell therapies, which exemplifies the next generation of endovascular solutions to stem cell technology and promises safety, efficacy, and reliability.

Therapeutic angiogenesis: a new treatment approach for ischemic heart disease--Part II

Angiogenesis is the biologic process of forming new blood vessels and is being investigated as an innovative therapeutic approach to help manage ischemic heart disease and peripheral vascular disease. Research studies have identified various angiogenic growth factors and progenitor cells that can enhance new blood vessel formation. This is Part II of an article that began publication in the July/August issue of Cardiology in Review. Preclinical investigations in animal models have explored the potential use of growth factors with and without progenitor cells to treat myocardial ischemia. The results of clinical trials with growth factor infusions and gene therapy techniques to enhance growth factor production have shown some promise, but therapeutic angiogenesis remains at an early stage of development.

Angiotensin II Receptor Blocker Inhibits Neointimal Hyperplasia Through Regulation of Smooth Muscle–Like Progenitor Cells

Objectives— Angiotensin II (ATII) type 1 receptor (AT1R) blocker (ARB) has been shown to inhibit neointimal formation. Bone marrow–derived mononuclear cells (BM-MNCs) give rise to smooth muscle (SM)-like cells at injured arterial wall and contribute to neointimal formation. However, role of the renin—angiotensin system in the homing process of SM-like cells during neointimal formation is unknown.

Material and Methods— When human BM-MNCs and peripheral blood MNCs (PB-MNCs) were cultured under treatment with PDGF-BB and bFGF, these cells gave rise to SM-like cells with expression of αSMA, SMemb, and SM1 proteins. RT-PCR showed the expression of AT1R, ATII type 2 receptor (AT2R), αSMA, and SMemb mRNAs. ATII accelerated the differentiation of SM-like cells, which was inhibited by an ARB CV11974 ( P <0.05). We then examined the effects of ATII, CV11974, and AT2R antagonist PD123319 on neointimal formation and BM-derived SM-like cell incorporation at injured arteries in vivo. BM from green fluorescence protein (GFP)-transgenic mice was transplanted to irradiated WT mice. GFP-BM chimera mice were subjected to wire injury on the left femoral artery. ATII (100 ng/kg/min) stimulated whereas CV11974 (1 mg/kg/d) inhibited neointimal formation. Number of GFP + αSMA + cells at neointima correlated with the intima/media ratio ( r =0.69, P <0.05).

Conclusion— BM-derived SM-like progenitor cells contributed to the neointimal formation after arterial injury. ATII accelerated whereas ARB suppressed this process. These are new aspects of the ARB-mediated inhibition of atherosclerotic disease progression.

Bone-marrow mononuclear cell therapy of severe ischemic heart failure

We describe cell therapy for severe ischemic heart failure using transendocardial injection of autologous bone-marrow-derived mononuclear cells. The treated patients had significantly less heart failure and angina, sustained significant improvement of pumping power, exercise capacity, cardiac muscle irrigation, and blood supply to the body. Electrical and mechanical mappings of the myocardium before and after the therapy, and anatomopathological examination of the myocardium of one of the patients that had deceased of a stroke eleven months after the treatment indicated sustained neoangiogenesis and improvement of activity and quantity of cardiomyocytes in the injected regions. Post-hoc analyses of injected cell phenotype and improvement of myocardial function indicate that presence of CD8+ and CD56+ cells does not correlate with good prognostics, suggesting a possibility of cell selection. For 'no-option' severe cardiac patients, significant benefits of cell therapy and absence of adverse effects may justify the application of bone-marrow-derived cell therapy.

A Novel Approach to Therapeutic Angiogenesis for Patients With Critical Limb Ischemia by Sustained Release of Basic Fibroblast Growth Factor Using Biodegradable Gelatin Hydrogel An Initial Report of the Phase I-IIa Study

BACKGROUND

Limb ischemia remains a challenge. To overcome shortcomings or limitations of gene therapy or cell transplantation, a sustained release system of basic fibroblast growth factor (bFGF) using biodegradable gelatin hydrogel has been developed.

METHODS AND RESULTS

A phase I-IIa study was performed, in which 7 patients had critical limb ischemia. They were intramuscularly injected with 200 microg of bFGF-incorporated gelatin hydrogel microspheres into the gastrocnemius of the ischemic limb. End-points were safety and feasibility of treatment after 4 and 24 weeks. One patient was excluded from the study for social reasons, but only after symptomatic improvements. In the evaluation of the other 6 patients, significant improvements were observed in the distance walked in 6 min (295+/-42 m vs 491+/-85 m for pretreatment vs after 24 weeks, p=0.023) and in transcutaneous oxygen pressure (53.5+/-5.2 mmHg vs 65.5+/-4.0 mmHg, p=0.03). The rest pain scale also improved (3.5+/-0.2 vs 1.0+/-0.6, p=0.022). The ankle-brachial pressure index improved at 4 weeks but not at 24 weeks. Among 5 patients who had a non-healing foot ulcer, the ulcer was completely healed in 3 patients, reduced in 1, and there was no change in 1 patient at 24 weeks. The blood levels of bFGF were undetected or within the normal level in all patients.

CONCLUSIONS

The sustained release of bFGF from gelatin hydrogel might be simple, safe, and effective to achieve therapeutic angiogenesis because it did not need genetic materials or collection of implanted cells, and because it did not have any general effects, which was supported by there being no elevation of the bFGF serum level.