In a proof-of-concept study, investigators at the Mayo Clinic, the United States, have demonstrated that induced pluripotent stem (iPS) cells can be used to treat heart disease. In this study, the researchers reprogrammed ordinary fibroblasts, cells that contribute to scars such as those that result from a heart attack, converting them into stem cells that fix heart damage caused by infarction. Bioengineered fibroblasts acquired the capacity to repair and regenerate infarcted hearts, says Dr. Timothy Nelson, first author of the study.

This is the first application of iPS-based technology for heart disease therapy. Previously iPS cells have been used on only three other disease models: Parkinsons disease, sickle cell anaemia and haemophilia A. The ultimate goal is to use iPS cells derived from patients to repair injury. Using a persons own cells in the process eliminates the risk of rejection and the need for anti-rejection drugs. This iPS innovation lays the groundwork for translational applications, says Dr. Andre Terzic, Mayo Clinic physician-scientist and senior author.

The Mayo Clinic team genetically reprogrammed fibroblasts via a stemness-related human gene set to differentiate into an iPS cell capable of then redifferentiating into new heart muscle. When transplanted into damaged mouse hearts, iPS cells engrafted after two weeks, and after four weeks significantly contributed to improved structure and function of the damaged heart, in contrast to ineffective ordinary fibroblasts.
Source: www.biocetera.com

Researchers have found a way to directly convert spermatogonial stem cells (SSCs), the precursors of sperm cells, into tissues of the prostate, skin and uterus. Their approach may prove to be an effective alternative to the use of embryonic stem cells. The new method, developed at the University of Illinois, the United States, takes advantage of the unusual interaction of two tissue types: the epithelium and the mesenchyme. The epithelium lines the cavities and surfaces of glands and many organs, and secretes enzymes and other factors that are essential to the function of these tissues. The mesenchyme is the connective tissue in embryos. The epithelium takes its developmental instructions from the mesenchyme.

Veterinary biosciences professor Dr. Paul Cooke and post-doctoral researcher Dr. Liz Simon began the effort with an unlikely proposition: cause SSCs to directly change into other cell types by putting them with various mesenchymes and then growing them in the body. Surprisingly, the experiment did work. When SSCs from inbred mice were placed on prostate mesenchyme and the combination grafted into living mice, the SSCs became prostatic epithelium. When combined with skin mesenchyme and grown in vivo, the SSCs became skin epithelium. The researchers were even able to convert SSCs into uterine epithelium by using uterine mesenchyme. The new tissues had all the physical characteristics of prostate, skin or uterus, and produced the telltale markers of those tissue types. They also stopped looking and behaving like SSCs, Dr. Cooke said.
Source: www.medicalnewstoday.com

Researchers in the United States have discovered a compound that can kill breast cancer stem cells, a kind of master cancer cell that resists conventional treatment, and explained why many cancers grow back. The discovery came using a new method of screening for drugs that specifically target and kill cancer stem cells. It could be used to find drugs targeting other cancer stem cells as well, said Dr. Piyush Gupta of the Massachusetts Institute of Technology and the Broad Institute, whose study appears in the journal Cell.

Dr. Guptas team devised a method for stabilizing cancer stem cells in the lab and getting them to multiply. They then tested the cells against 16,000 natural and commercial chemical compounds to see which ones were able to kill the cancer stem cells specifically. That turned up 32 contenders, buy they narrowed down this list to a few chemicals and tested these in the lab and in mice. A chemical called salinomycin was found to be 100 times more potent at killing breast cancer stem cells than the cancer drug paclitaxel. Cancer stem cells treated with salinomycin were far less able to start breast cancers when injected into mice than those treated by paclitaxel. The treatment also appeared to slow the growth of tumours in the mice.
Source: www.reuters.com

Tiny synthetic particles carrying a payload of toxin worked as well as chemotherapy at killing ovarian cancer cells in mice, without the bad side effects, researchers in the United States said. The treatment, which relies on the use of nanotechnology to deliver genetic material into cells, could be ready for human clinical trials in about a year. What we did was deliver DNA that basically tells cells to die. But it is only turned on in ovarian cells, said Dr. Dan Anderson of the Massachusetts Institute of Technology. The study highlights the potential of nanotechnology as a non-viral way of getting DNA into cells. To circumvent the safety issues, Dr. Andersons team created an artificial virus a biodegradable polymer that can get inside the cell and be absorbed by the body, in much the same way biodegradable sutures work.

We think that has got a variety of advantages, in particular, safety, said Dr. Anderson, who worked with a team at the Lankenau Institute. The team tested different compounds until they found a biodegradable polymer that would make a suitable delivery vehicle. To form the nanoparticle, the polymers are mixed with a gene that produces a modified form of the diphtheria toxin that is only harmful to ovarian cancer cells. When they injected the treatment into the abdominal cavity of animals with ovarian cancer, it worked as well or better than the traditional chemotherapy drug combination of cisplatin and paclitaxel, which can cause DNA damage and a variety of side-effects.
Source: www.newsdaily.com

For the first time, scientists have used a genetically engineered friendly bacterium to deliver a therapy. The treatment is for bowel disorders such as inflammatory bowel disease (IBD), which has no cure. The bacterium Bacteroides ovatus activates a protein when exposed to a specific type of sugar, xylan. The therapy has been proved to work in animals with colitis, one of the major forms of IBD. The bacterium is able to deliver the protein, a human growth factor called KGF-2, directly to the damaged cells that line the gut. Unlike other treatments, the patients would be able to control the medication themselves by ingesting xylan, perhaps in the form of a drink.

"This is the first time that anyone has been able to control a therapeutic protein in a living system using something that can be eaten, said lead author Prof. Simon Carding of the Institute of Food Research and University of East Anglia Medical School, the United Kingdom. The treatment had a significant effect. For example, it reduced rectal bleeding, hastened the healing of the gut lining, and reduced inflammation. It also prevented the onset of disease.
Source: www.scienceblog.com