MAGIC-Cell: GM-CSF and Peripheral Stem Cell Infusion Improved Endothelial Healing

Two-year outcomes in patients with MI showed trends toward clinical improvement.

The MAGIC-Cell series of trials have indicated that granulocyte macrophage colony-stimulating factor (GM-CSF) along with intracoronary infusion of peripheral blood stem cells can improve endothelial healing and prevent DES thrombosis.

While none of the clinical outcome measures of the MAGIC-Cell 3 trial showed a significant difference after two years of follow-up, there were trends toward benefit with cell infusion in all measures. These included any revascularization (P = .157), de novo PCI (P = .114) and non-TLR TVR (P = .328).

MAGIC-Cell evaluated a total of 154 patients with acute or prior MI divided into cell infusion or control groups. It examined whether GM-CSF and stem cell infusion affected endothelial healing at DES sites or after brachytherapy. Results of the study, conducted at Seoul National University Hospital in South Korea, were presented by Hyo-Soo Kim, MD, PhD.

Earlier rabbit studies showed that GM-CSF can accelerate re-endothelialization, as well as preventing thrombosis following radiation. “Such a beneficial action can be extrapolated to clinical outcomes,” Kim said. He added that there is evidence that GM-CSF and stem-cell infusion can prevent neointimal hyperplasia in addition to thrombosis.
Mesenchymal stromal cells

Another study presented by Jens Kastrup, MD, DMSc, aimed to establish a method for ex vivo culture expansion of bone marrow-derived mesenchymal stromal cells for clinical use, as well as evaluating the safety and efficacy of direct intramyocardial injection of endothelial progenitor cells. The study included 40 patients with chronic myocardial ischemia and no further revascularization options as well as 16 control patients from an earlier study. The clinical effects of the treatment have yet to be established, and “we have had no safety concerns. We have had no serious adverse events,” said Kastrup, who is Associate Professor and Director of Angiogenesis Research at Copenhagen University Hospital in Denmark.

Candidates for cellular therapy

These types of therapies may eventually provide good treatment options for patients who are classified as non-revascularizable, according to Thomas J. Kiernan, MD, of the Mayo Clinic College of Medicine. Kiernan presented a study examining the number of patients who are thus classified and who may benefit from treatments other than PCI or CABG.

Of a total of 347 patients in Olmsted County in Minnesota who had previously undergone CABG and had CCS III-IV angina, 177 underwent further revascularization and 170 were treated medically. Of the 170 who were treated medically, angiographic analysis determined that 92 were not revascularizable. These results were used to extrapolate that approximately 50,000 nonrevascularizable angina cases per year (95% CI, 40,000-61,000) occur in the United States. Kiernan said that this enormous number of patients all represent possible candidates for the types of cellular therapies currently being studied.TCT Daily Vision Delivers OnlyAMI indicate.