Pulse
From Cord Blood to Lung Cells
University of Minnesota researchers have turned umbilical cord blood stem cells into a type of lung cell.
Led by David McKenna, M.D., medical director of the Clinical Cell Therapy Lab at the University of Minnesota Medical Center, Fairview, the team differentiated the cord blood cells into type II alveolar cells. Those cells are responsible for secreting surfactant, which keeps air sacs in the lungs open and helps repair the airway after injury.
The cells develop late in the fetus and continue to mature during the first years of life.
McKenna and his team are trying to better characterize the cells so they might be used to study lung diseases and test potential new drugs.
The findings were published in the November 7, 2006, issue of Cytotherapy.
Molecular Clues to Mysterious Deaths
A Mayo Clinic study of 49 young people who died unexpectedly and without explanation, found that more than one-third had heritable genetic defects that disrupt the heart’s rhythm center.
A team led by Michael Ackerman, M.D., Ph.D., who heads Mayo’s Windland Smith Rice Sudden Death Genomics Laboratory, conducted a postmortem genetic test—molecular autopsy—and discovered one of two mutations in the genetic code in 17 of the cases. Those mutations produced abnormal heart rhythms—long QT syndrome and catecholaminergic polymorphic ventricular tachycardia, both of which exist silently, with sudden death being the first symptom. In addition, such defects cannot be detected by conventional autopsy.
The cases were referred to Mayo by 42 coroners’ offices from across the country between 1998 and 2004; the average age of the study subjects was 14 years.
The findings were published in the January 16 issue of the Journal of the American College of Cardiology.
Thai Trial
Research on cellular therapies is a global endeavor. That fact was illustrated last month when Kitipan V. Arom, M.D., Ph.D., one of the founders of Abbott Northwestern Hospital’s Minneapolis Heart Institute who now heads a heart hospital in Bangkok, Thailand, spoke to physicians at St. Joseph’s Hospital in St. Paul.
Arom described a recent clinical trial undertaken in Thailand but done in cooperation with the University of Pittsburgh that involved heart patients from multiple countries. The goal of the trial was to test the safety and efficacy of a laparoscopic technique for delivering the patient’s own progenitor cells to damaged heart tissue.
The 97 patients in the trial had end-stage heart disease (functional class III or IV) and were not candidates for any therapies other than transplantation. Sixty-five percent came from the United States. When they arrived in Bangkok, blood was drawn and shipped to Israel, where it was separated and the stem cells were cultured. Within five days, the stem cells were returned to Bangkok, where they were injected into the patient’s heart wall through tiny incisions in the chest.
Arom reported that early results have been positive, with more than 80 percent of patients showing improvements in quality of life and a variety of other parameters including thickening of muscle, disappearance of scarring, and increasing contractility.
Arom noted that they had expected to see an increase in cardiomyocytes in the patients’ hearts but instead saw an increase in vasculature. So when asked why and how the therapy itself works, he answered, “It works, but not the way we expected. And how? Nobody knows.”—Carmen Peota
Athletes Bank Stem Cells
Will stem cells one day keep injured athletes in the game? Some doctors and researchers say that might just be the case, according to a March 29 New York Times article.
The article described how stem cell blood banks are promoting the idea that one day primitive stem cells from umbilical cord blood may be used to grow new knee ligaments or elbow tendons and how some sports agents are advising their clients to bank stem cells from their offspring or from tissue in their own bodies as insurance against a career-ending injury.
It also quoted a Times of London article that told of five professional soccer players who had frozen their children’s stem cells at birth and were storing them at a Liverpool stem cell bank.
Skeptics contend that using regenerated cartilage in knees hasn’t been highly successful so far and expressed concern about using the technology to build muscle in order to enhance performance.
Researcher Under Fire
When University of Minnesota stem cell researcher Catherine Verfaillie, M.D., published her findings on the potential for adult bone marrow stem cells in 2002, the British magazine New Scientist heralded the discovery with the headline “Ultimate stem cell discovered.”
In a paper published in Nature that year, Verfaillie and her team reported how they made such cells in mice differentiate into cells that lined the blood vessels and the vessels in the lymphatic system. She was quoted as saying that she envisioned the multipotent adult progenitor cells as having the potential to one day treat atherosclerosis, heal ulcers, and fight cancerous tumors. “The findings suggest that these adult stem cells may be an ideal source of cells for clinical therapy,” she said in the February 25, 2002, issue of American Medical News.
Since then, scientists have had difficulty replicating the findings. And earlier this year, a reporter from New Scientist called them into question after discovering figures that appeared in the Nature article also appeared and were labeled differently in another paper Verfaillie published in Experimental Hematology.
When Verfaillie, who is now at Catholic University of Leuven in Belgium but is still a member of the University of Minnesota faculty, was contacted about the data, she called it a mistake and published a correction in Experimental Hematology, explaining that the correct legend had been omitted.
University of Minnesota officials conducted their own review and concluded that there were “technical flaws with the paper.” According to a February 26, 2007, article in The Scientist, one of the university’s external reviewers said the flaws would not have affected the findings; another said they might “weaken the conclusions.”
In late March, New Scientist reported that the University of Minnesota and Catholic University of Leuven have launched further inquiries into Verfaillie’s work after reporters discovered new discrepancies: Three images that appeared in an article on adult stem cells by her group in a 2001 issue of Blood were apparently used to describe different results in a U.S. patent application, and one of the images may have been used twice within the Blood paper to represent results from two different experiments.