Do you know anyone with Parkinson’s disease? Do you know anyone who’s blind or has diabetes? According to national surveys, there are an estimated 1.3 million Americans with Parkinson’s disease (National Parkinson Foundation [NPF], 2002), 1.1 million Americans who are currently blind (National Federation of the Blind [NFB], 1992), and a stunning 17 million Americans with diabetes (National Institute of Diabetes & Digestive & Kidney Disease [NIDDK], 2000). But what if these statistics could suddenly plummet? What if there was a way to cure diabetes, to stop the progress of Parkinson’s disease, and to reverse blindness? Current scientific research may have found a panacea that can do just that. The key to the so called “cure-all” lies within stem cell research, a new field of biotechnology that is as innovative as it is promising.

Stem cell research revolves around the use of cells extracted from human embryos that have the potential to differentiate into every kind of tissue found in the body, such as muscle, blood, and nerve. This characteristic of cell differentiation is known as pluripotency, an ability which in the past had been thought of as an intrinsic property of human embryonic stem cells alone. If the mechanism that controls their differentiation into specific tissue types can be identified and utilized, embryonic stem cells can be used to replace damaged tissue throughout the body. Stem cells also exist in most of the adult tissue types in the body as tissue-specific stem cells which were thought to be able to differentiate into only a few lineages of tissues and to have limited self-renewal ability when compared with embryonic stem cells (Jiang et al, 2002). The variation between the differentiation abilities of embryonic and tissue-specific stem cells is what has made embryonic stem cells the preferred candidate for stem cell research. The use of embryonic stem cells, however, poses various problems. In terms of the biological mechanics involved, transplanted embryonic stem cells have sometimes been known to metastasize into tumors and they risk the possibility of being rejected by the immune system of the recipient (Pearson, 2002). Ethically, there has been a lot of controversy surrounding the use of stem cells for research purposes. Embryonic stem cells can only be extracted in a way which destroys the embryo. This has been a point of contention and controversy ever since the idea of using embryonic stem cells developed (Onion, 2002).

A recent breakthrough, however, may serve to circumvent the need for embryonic stem cells. Catherine Verfaille and her team at the University of Minnesota discovered a unique tissue-specific stem cell in bone marrow that is truly pluripotent, like embryonic stem cells. According to Verfaille’s lab reports, these newly discovered tissue-specific stem cells were injected into developing mice embryo, which were allowed to develop and grow to adulthood. If these tissue-specific stem cells were truly pluripotent, Verfaille would have expected to see these cells spread, multiply, and most importantly, differentiate into tissue throughout the body. By studying microscopically thin slices of tissue taken from tested mice and looking for an identifying chemical tag on the organs, Verfaille was able to see which organs in the mice actually had the injected tissue-specific stem cells. The pluripotency of these newly discovered, tissue-specific stem cells was show when Verfaille found the identifying tags in just about every organ in the adult mice. Her experiments on mice may one day prove to be a viable solution to extracting truly pluripotent stem cells from embryos (Verfaille, 2002).

Despite the current concerns about the use of embryonic stem cells, a series of recent experiments with embryonic stem cells by labs all over the United States have shown great promise. Ron McKay, of the National Institutes of Health in Bethesda, Maryland, and his team have recently transplanted embryonic stem cells into the brains of rats with Parkinson’s disease, a disease caused by the death of specific nerve cells in the brain. McKay simulated the disease in mice by engineering mice with defective nerve cells and then injected the affected mice brains with embryonic stem cells. McKay’s experiments showed that the injection of embryonic stem cells into the affected areas of the brain was able to reverse the effects of the disease (Pearson, 2002).

Martin Friedlander, ophthalmologist at the Scripps Research Institute in La Jolle, California, and his team have injected mice with embryonic stem cells so that they would differentiate into and redevelop retinal blood vessels. Friedlander’s technique can be used in the future to cure genetic, diabetic, and age related blindness (Powell, 2002). These cells may even be injected into the body to replace damaged organ tissue in hopes of curing diseases such as diabetes (Pearson 2002).

Stem cell research will be a viable medical solution to currently incurable diseases and disorders in the near future. The limited research that has already been done in this field has already shown the possibilities that stem cells yield to the medical and scientific community. With the recent discovery of pluripotent tissue-specific stem cells, the dangers and limitations of working with embryonic stem cells may soon be avoided. Only future tests can truly prove if stem cell research is truly the answer to curing diseases once thought to be incurable. However, judging from current experimentation and the positive results so far, it is more than likely that stem cells are indeed the “cure-all” that science and medicine have been searching for.

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