Stem Cell Projects
Anthony Rommens
16-Jan-07
Stem Cell Research offers immense promise but also ethical controversy. This article provides business investors with a brief background and also explores the topic so that they can make their own personal decisions of whether to invest in the field as opportunities arise.
For many centuries, scientists have been aware that certain animals like Salamanders and Starfish can regenerate entire limbs or body parts. Humans also share this natural ability (albeit much more limited) to replace or repair some blood cells, liver, skin and other tissues. The cells that have been identified to be able to replace tissues are called Stem Cells.
WHAT ARE STEM CELLS?
In the 1960’s, Canadian scientists first recognised Stem Cells as those that allow us to regenerate tissues. Stem Cells (comparable to undifferentiated cells in plant buds) are basic cells in organisms that have the ability to propagate and develop into specialised cells. There are over 200 different specialised cell types, in the human body. Stem Cells, by definition, can grow into any of these cell types that perform specific body functions including those that make up muscle, skin, blood, neural tissue (spinal cord & brain), etc. Doctors have been successfully performing bone marrow therapy for decades. Patients with leukemia (blood cancer), sickle cell anemia or bone marrow failure have been successfully treated with bone marrow transplants from genetically similar donors. Once bone marrow transplants (source of blood Stem Cells) were successful, scientists, then thought of locating Stem Cells for other organs.
EMBRYONIC STEM CELLS
Every cell in the human body can be traced back to the single cell formed from the union of egg and sperm. As the cell begins dividing, the young embryo is a very rich pool of Stem Cells. Over the last twenty years, scientists have been slowly elucidating the processes by which the unspecialised Stem Cells become the many different types of cells in the human body.
The cells from these most early stages of an organism’s development are called Embryonic Stem Cells. Scientists have been able to extract Embryonic Stem Cells from mice since 1980. It wasn’t until 1998 that US scientists were able to isolate Human Embryonic Stem Cells and were able keep them alive in a laboratory. These cells were considered Stem Cells because they can replicate to make more Stem Cells, grow and transform into the different cell types that make up all body organs. Embryonic Stem Cells are specifically obtained from the inside cell mass of the hollow sphere the young pre-implantation embryo (blastocyst). This inner cell mass is composed of 30 to 34 cells that are together smaller than the period at the end of this sentence.
During normal development, the blastocyst attaches to the wall of the uterus. The outer cells form the placenta and the inner cell mass differentiates into the fetus body with all of its specialised cell types. When the blastocyst is used for stem cell research, scientists remove the inner cell mass cells and place them in a Petri dish within a nutrient rich liquid environment. These Embryonic Stem Cells are generally easier to collect and maintain than Adult Stem Cells.
Scientists can make Embyronic Stem Cells replicate into more stem cells for extended periods of time before stimulating them to become specialized. This is beneficial for researchers because it is thought that only a few Embryonic Stem Cells are required to generate a large number of stem cells for use in experiments. Stem cells are not likely to be directly useful for tissue transplantation as tumors (called teratomas) may develop. To be useful for treatment, the Stem Cells need to be differentiated into specialised cells types.
FERTILITY CLINICS
The largest potential source of blastocysts is from fertility clinics. In assisted reproduction, the process of ‘invitro’ fertilisation involves obtaining a woman’s eggs by a surgical procedure after she is injected with a variety of ‘fertility drugs’ to stimulate her ovaries to produce many mature eggs. Doctors then fertilise all donated eggs to increase the chances of producing healthy early embryos that can be implanted into a womb.
Not all fertilised products are currently stored in fertility clinic freezers. The excesses could be a potential source of Stem Cells for use in research. However, most donors have not given informed consent for Stem Cell Research. There nuclear transfer to develop disease free Stem Cells for personalised tissue implantation. The idea is to use genetically similar or healthy nuclear material from a patient or close relative to generate sources of healthy cells to treat diseased organs. With these cells there should be little chance of rejection by the immune system. It is hoped that scientists can one day use human Stem Cells and Stem Cell lines for treatments of many diseases. Stem Cells could also allow for rapid screening of thousands of pharmaceutical compounds thus making drug discovery more efficient and cost effective with little danger to living patients and test subjects (animal or human). It is worth noting that Stem Cells are not only found in embryos but also in human tissues as growth occurs later in life.
ADULT STEM CELLS
There are also Stem Cells found in various organs in adult stages, so called Adult Stem Cells. Adult Stem Cells can be found in certain tissues in adults and depending where they are found in the body, they may be already be somewhat specialised and thus limited to producing only certain types of cells. Such Stem Cells, or progenetor cells, are much more difficult to find than Embryonic Stem Cells because they are often hidden within millions of cells that make up organs or tissues.
Adult Stem Cells are found in many different areas of the body (even the Brain), in particular, in those areas that need a steady supply of new cells, such as blood, skin, liver and intestine. Researchers hope to produce Adult Stem Cells that are versatile and able to create a wide variety of cells. The state of this research is still in its infancy, but rapid progress is being made. The techniques for identifying (via surface protein ‘markers’) have only recently been developed. Some scientists remain skeptical about the nature and existence of Adult Stem Cells. Hematopoietic Stem Cells that give rise to all the blood cell types are the essential ingredient of bone marrow transplants. They work very well as long as the donor’s genetic material is similar to that of the patient being treated. Thus Hematopoietic Stem Cells from the usually discarded umbilical cord and placenta at birth are being collected and used for therapies latter in life and are successful as they originate from the patient and are perfect genetic matches. Cord blood banks are already being established to harness this potential source of Stem Cells.
The idea of medical treatment that involves growing healthy tissue from Stem Cells has been of particular interest to scientists, doctors and business people. Scientists hope to grow Stem Cells, and in, the process discover how cells differentiate and develop into organs. They also hope to discover improved methods for drug discovery. Doctors wish to develop new therapies that replace and rebuild damaged cells using tissues grown from Stem Cells in order to cure patients suffering from cancer, diabetes, cardiovascular disease, spinal-cord injury, Parkinsons and many other diseases. Early Investors are interested not only for humanitarian reasons but to profit by owning the valuable information on the processes, cell growth factors involved, and the proprietary steps of how to create and/or get Stem Cells to specialise.
There are three immediate areas of research regarding Stem Cells. The first is to Identify Stem Cells, the second is culture healthy Stem Cells, and the third is to stimulate the Stem Cells to differentiate. Work in animals have provided the basic knowledge that are pointing towards medical advancements in humans.
DEBATE
There are many legal issues and ethical dilemmas that must be addressed before Stem Cell therapies become available. There are legal issues with regard to the intellectual property and how to apply and enforce diverse and apparently conflicting laws. There are also moral concerns regarding early human life and the status of the human embryo. Social issues on the destruction of embryos and protection of privacy interests as well as clinical research subjects must all be sorted out before full benefits can be realised.
CONCLUSION
Despite all the moral and legal concerns, Stem Cell research is being done throughout the world. It is difficult to appreciate how it is advancing because various countries and their local laws have influenced how it is being funded. Some of the debate and laws have driven the research into the private sector rather than being shared in public peer reviewed sectors (particularly in the USA). This makes it difficult to keep track of scientific findings and slows the overall advance and sharing of knowledge. Compared to many other developed countries, the United Kingdom has been more open to Stem Cell and therapeutic cloning research. This is good news for Business Angels who are open to related investments because they can take advantage of locally shared progress in these areas.
