“Stem Cell Therapy To Fix The Heart: A House Of Cards About To Fall?”
“A provocative new study calls into question the rationale for using stem cells to repair the heart — a much-hyped experimental therapy that grew out of insights from a groundbreaking Boston researcher’s laboratory.”
“All of the critiques have been leveled at competing technologies. Indeed, I have been among the more vocal critics (for example see http://www.tctmd.com/show.aspx?id=124193).
“Although some alarmist headlines have inappropriately questioned all cardiac stem cell work, the issues have to do with only one specific subtype of cardiac stem cell, which is marked by the expression of an antigen called c-kit. This is NOT the cell type being developed by Capricor; in fact, my laboratory has found that c-kit-positive cells play no role in Capricor’s cell product. That product, known as CAP-1002, contains a small fraction (less than 5 percent) of c-kit-positive cells which can be completely removed with no loss in potency. CAP-1002 is believed to work by indirect 'paracrine' mechanisms that differ fundamentally from those postulated for the c-kit-positive cells.
“By way of background, the critiques of c-kit-positive heart cells have come in two forms: first, in concerns expressed by the editors of the Lancet regarding data integrity in the SCIPIO trial; this was conducted by Piero Anversa and colleagues using c-kit-positive cells. Second, a recent Nature paper (attached in case you do not have a copy), of which I am an author, questions the claim that c-kit-positive cells are true cardiac progenitors.
“These concerns in no way undermine Capricor’s technology. In fact, CAP-1002 remains the only heart-derived cell product in commercial development. I am proceeding full speed ahead with mechanistic and translational work on CAP-1002, and Capricor continues to feel bullish about the product, which is now in phase 2 trials (the furthest along of any CIRM-funded project).”