Human-animal embryos don't work for stem cell production

The New Scientist has a good review article that explains a new research report from Robert Lanza of Advanced Cell Technology, that attempts with "thousands" of embryos created by placing human DNA into the oocytes or eggs of animals have failed to produce stem cells. NatureNews, the news arm of the journal, Nature discusses the report, here.

The abstract of the article, "Reprogramming of Human Somatic Cells Using Human and Animal Oocytes" published in Cloning and Stem Cells, is available here. The list of researchers is very long and they are from several different laboratories.

Each of the news articles above includes statements from researchers who do not believe that human-animal cloned embryos are a dead-end for stem cell researchers. However, the confirmation of the outcome from several labs, with different researchers, is strong evidence that it is unlikely that this technique is a reasonable way to produce "patient specific" stem cells - those that are an exact match for the donor of the DNA.

I have not read the actual article, yet, but from the news articles and the abstract, it appears that the "cybrids" do express the genes of the donor DNA and are clones of the donor. However, while enucleated human oocytes are able to reprogram the DNA of the donor to result in embryos that divide to the stage at which it is possible to harvest embryonic stem cells, the emptied eggs of cows and rabbits do not. The cybrids only divide to about the 16 cell stage and do not turn on the genes responsible for pleuripotency, or "stem-cell-ness."

See my Update, written after I read the report.

"Tea-bag" Adult Stem Cell Treatment for Stroke

British researchers report an amazing recovery for a 49 year old man who suffered a hemorrhagic stroke on October 15, 2008. The researchers at the company, "Biocompatibles," used adult stem cells from a healthy donor. The cells had been engineered to cause them to produce a protein that helps prevent "programmed" cell death (even after the bleeding stops and the pressure is removed) and embedded in tiny beads that had been sewn up in a cloth "tea-bag."

From the press release, published on the Medical News Today Neurology and Neuroscience website:

Stroke is one of the leading causes of death in the elderly population in the developed world. The incidence rate has been reported as 145 per 100,000. Hemorrhagic stroke is responsible for ~15 to 20% of all stroke and it is the least treatable form of stroke. It is associated with the highest morbidity and mortality rate of all stroke with only 44% of affected patients surviving the first 30 days. Only 20% of these survivors regain functional independence. The cascade of events starts with the sudden rupture of a blood vessel in the brain, causing haemorrhage and pressure inside the skull. Surgery may be used to relieve the pressure; but the haemorrhage causes a longer-term process of programmed cell death, or apoptosis, and it is this that causes the lasting neurological damage.

The CellBeads™ are delivered directly to the injury site during the surgery. They are programmed to deliver CM1, a proprietary version of a naturally occurring protein, GLP-1, which has been shown to have powerful anti-apoptotic effects. The delivery mechanism is a cluster of human adult mesenchymal stem cells obtained from a healthy donor and encapsulated in alginate beads. The cells are genetically engineered to produce the protein, which is delivered continuously, directly to the injury site. The alginate beads protect the stem cells from the body's immune system, which would otherwise destroy the foreign cells. CellBeads™ are transplanted within a retrievable mesh device and are removed completely after a treatment period of 14 days. Retrieval of the implant prevents possible long-term side effects from the transplanted cells.

The research is a "Phase I/II" trial, which means that the doctors and scientists are actually testing the safety of the treatment, and not the actual effectiveness of the treatment, itself. In other words, "does the treatment do more harm than good."

The CEO of Biocompatibles, Crispin Simon (that name is as British as tea bags), spoke to a Reuters reporter for a story published at Forbes online, stressing that the patient is young and other wise healthy, and had the standard of care for hemorrhagic strokes, surgery to relieve the pressure from the blood on the cells around the stroke. 10% to 20% of patients have similar recovery, without the Biocompatible beads.

Still, the report is a welcome source of hope for anyone who has watched and waited helplessly after a patient or a loved one had a hemorrhagic stroke.