Stem cell science is progressing at a rapid rate. Keeping up with all the facets of this ever-changing field can be tricky as researchers learn more and more about what stem cells can provide. One branch of research is devoted to the discussion of disease-specific and patient-specific induced pluripotent stem cells. Do you understand the difference between the two? Why are scientists excited about them? How do they work? What are the pros and cons of both? Learn the answers to these questions so you can be familiar with the possible ways this developing field could impact you.
At the base of regenerative medicine and 21st century medical research lies stem cell science and discovery. Stem cells are a starting point for doctors and researchers across the globe, but they are also the starting point of the human body. Every cell, every organ, every tissue begins with a stem cell. Stem cells have lured scientists for decades because of their ability to self-renew and form into a variety of specialized cell types. There are two main categories of stem cells: adult stem cells and embryonic stem cells.
Embryonic stem cells are taken from early on in the stage of development. They are pluripotent meaning they can become any cell type in the body (nerve cells, heart cells or liver cells.) Adult stem cells are considered multipotent. They can form cell types of the tissue or organ they reside in. They are most often found in types of tissues that continuously replenish themselves like blood or skin. Adult stem cells typically generate the cell types of the tissue or organ in which they reside and are called multipotent.
Embryonic stem cells and adult stem cells have garnished a lot of attention recently in drug development centers and disease study labs. In 2006, researchers in Japan gave us new buzzwords induced pluripotent stem cells.
Induced pluripotent cells (iPS cells) are adult cells that have been artificially modified (reprogrammed) to have pluripotent capabilities. This means that cells with a specific function (like blood or skin cells) are reprogrammed to be able to form all cell types of the body. Since this development, scientists have greatly improved the techniques to engineer iPSCs, creating a powerful new way to “de-differentiate” cells. iPSCs give scientists an alternative, pluripotent cell to human embryonic which could help with some of the ethical concerns surrounding ESCs.
Fast forward a few years, and scientists made other breakthroughs with induced pluripotent stem cells. US scientists produced a robust collection of disease-specific stem cell lines, all of which were developed using the new induced pluripotent stem cell (iPS) technique. These new stem cell lines will make it possible for researchers to explore ten different genetic disorders—including muscular dystrophy, juvenile diabetes, and Parkinson’s disease—in a variety of cell and tissue types as they develop in laboratory cultures. Researchers can study the disease in the test tube instead of in the patient. This method allows scientists to study “healthy” tissue cultures with the genetic code of the disease as well as the diseased tissue.
These new iPS cell lines will model human diseases better than animal models. Although animal models (like mice) are similar to humans their differences can isolate certain diseases that need research. (One example is Down’s syndrome; it does not cause the same symptoms in mice as in humans). Disease-specific iPS cells help researchers:
Patient-specific iPSCs are used for studying diseases with complicated mechanisms. Some diseases are influenced by various factors like genetic background and environmental modifications. Patient-specific iPS cells provide helpful information for understanding the pathophysiology of disease. They provide a better method for drug testing than the current method. By using patient-specific IPS cells from patients who are suffering from specific diseases, researchers can develop more treatment options and improve diagnostic accuracy.
It is difficult to collect sufficient amounts of cells from individuals affected by disease to be able to do these studies. However by transforming a patient’s cells into an iPSC line that can multiply almost indefinitely, a long-term supply of useful cells can help various research studies without the risk of running out.
Scientists, researchers, universities and medical centers around the globe have come together in an international effort to help the field of stem cell science and research progress. In 2012, StemBANCC was organized with international support to establish a collection of iPS cell lines for drug screening for different diseases. Managed by the University of Oxford, funds and resources were gathered from 10 pharmaceutical companies and 23 universities. The mission of StemBANCC is to create a storehouse of 1,500 iPS cell lines to help with early drug testing through a simulated human disease environment.
The 21st century is an exciting time for the field of stem cell science. Although there are still obstacles to overcome, with the progress that has been made in the last decade alone, the future looks bright for understanding and treating disease with various stem cell applications.