Apr 25, 2012Science and Technology
Neural stem cells and regenerative medicine may be key to disease treatment

Neural stem cells, shown here in red, have potential to treat a variety of disorders.Regenerative medicine describes a relatively new avenue of biomedical and clinical research, involving the discovery of novel techniques to restore lost tissue function in the human body.

Core Dynamics, an Israeli-based company, for example, has developed a novel way to freeze-dry and rehydrate cells. Formation of ice crystals during the freezing process can rip living tissue, causing unwanted tissue damage, which is why frostbite can be so dangerous. But freeze-drying could be a boon to health care. For example, a way to store blood at room temperature would be a great cost saving measure, but more than that, it could also allow blood to reach remote, rural areas with ease. Core Dynamics is working on developing a process to safely freeze-dry blood cells. Once perfected, this method could lead to long-term storage of tissue, with a greater level of survival once it is rehydrated.   

Stem cells are likely the most well-known aspect of regenerative medicine, as they have had a lot of media attention in both controversy (e.g., initial banning of federal funding due to use of embryonic stem cells) and as the implied cure for all that ails you (e.g., comedic tactics in "Family Guy" and "South Park"). While stem cells may not be curing illness in five minutes like they do on "Family Guy," stem cell science has come a long way since the early days of research.

One reason why their clinical use has not been as effective as previously hoped is that these cells can easily and quickly differentiate into a variety of tissues, making maintaining a pure cell product difficult. The discovery of adult early-lineage stem cells, however, shows promise in the pre-clinical and the clinical setting.   These stem cells generally only develop into certain cell types and are, therefore, often less likely to differentiate into a wide variety of unwanted cells. This provides a purer product to patients, which is an important aspect for FDA approval.  Many of these adult cell populations are often autologous (from the patient's own body) and are less likely to induce an unwanted immune response. A recently discovered example of these cells is a new source of stem cells in the central nervous system found by researchers at Lund University. The function of this cell population is not entirely understood, but since it shows the ability to differentiate into a wide variety of nerve cells, it likely plays an important role in wound healing and repair.  With further experimentation, the researchers hope to adapt this cell population to be used in the treatment of neurodegenerative diseases such as Parkinson’s disease and Alzheimer’s disease, as well as brain cancer.

Human induced pluripotent stem (iPS) cells have also shown promise in regenerative medicine.  By inducing specific stem cell populations from less differentiated cells, cell populations which are directly downstream of specific tissues, are less likely to become randomly contaminated with unwanted cell types.  At the Institute of Bioengineering and Nanotechnology (IBN), researchers have shown that human iPS cells derived from an adult neuronal stem cell line can be used to combat brain tumors, and tumors of other organs as well. With a mouse breast cancer experimental model, the researchers found that iPS cells easily found and integrated into the primary breast and metastatic tumors.  A suicide gene, which is activated by the compound gancyclovir, was transfected into iPS cells, and successfully led to breast tumor cell death. 

Although some stem cell research has shown great promise, there have also been major limitations, especially with regards to its production and commercialization.  Much of the research discussed in this article, for example, is still has a way to go before it becomes a health care mainstay.  With that said, in the last decade, the science community has learned a lot with regards to stem cells and regenerative medicine and several clinical trials are presently underway or have shown success in the treatment of a variety of disorders.

Sarfraz Ahmadfinding ways to reactivate stem cells and control their target destination might create unforeseen opportunities for curing degenerative diseases
Apr 25, 2012