What are stem cells?
Stem cells are essential to human development. They are non-specialized cells, which have the capability of creating other types of specific cells. Stem cells are in our bodies for our entire life, but they have the more potential to create new cells in the fetus than in the adult body. Some types of stem cells may be able to create all other types of cells in the body, while others repair and replace damaged tissue or cells.
Embryonic stem cells are derived from embryos and can create all cell types in the body. However, embryonic stem cells carry the risk of transforming into cancerous tissue after transplantation. To be used in cell transplant treatments, the cells would need to be directed into a more mature cell type, both to be therapeutically effective and to avoid the risk of cancerous tissue development. While embryonic cells hold enormous promise for future therapies, iPS cells are much more widely accepted in the medical community as of right now.
In 2006, scientists figured out how to reprogram cells that had a specialized function (e.g. skin cells, blood cells, muscle cells, etc.) so that they act like an embryonic stem cell. These cells are called iPS cells, which is short for “induced pluripotent cells”. By inducing specialized cells to express genes that are normally expressed in the embryonic stem cell and control how it operates, iPS cells are created. Embryonic stem cells and iPS cells share many characteristics, including the capability of becoming the cells of all organs and tissues. But though they share similar traits, they can sometimes behave slightly differently.
Adult stem cells are specific to a certain tissue, meaning they are found in a given tissue in our bodies and they produce the mature cell types within that particular tissue or organ to repair and maintain that tissue. There are a few stem cell therapies that are common amongst the medical community and they use adult, or tissue-specific stem cells. Bone marrow or cord blood is used in stem cell transplantation to treat diseases and conditions of the blood or to replenish the blood system after treatment for specific cancers. Skin stem cell therapies for burns and limbal stem cells for corneal replacement are also common. In each instance, the stem cells repair the same tissue from which they originated.
Stem cells are able to cure and treat various diseases because they have the ability to become any kind of tissue. This means that, for example, when incorporated into a brain that may be devastated by Alzheimer's disease, they become healthy brain cells, and are then able to help the brain function normally again. Since stem cells have the ability to generate into any form of a healthy cell, stem cells have the means to treat and/or cure a wide spectrum of diseases. These types of diseases include degenerative genetic disorders that currently afflict millions of people, such as Parkinson's disease, multiple sclerosis and muscular dystrophy. In addition to potentially having the ability to treat and cure various diseases and disorders, stem cells have also shown noticeable potential in treating spinal cord injuries. Overall, stem cells could lead to significant benefits for individuals and tremendous gains for society.
Sam,
ReplyDeleteYou have more than the necessary information, as usual. But above your normal standards, I love the timeline that you, in essence, created in the blog. By including the dates of important scientific discovery, you were really able to emphasize the short time stem cells have been around and how the impact will be seen in the future. I also enjoyed your holistic approach. You weren't scientific and detached, there was an honest tone which can be seen through the fixation on the success of stem cells in the future and the benefits (and gains) for society.
Molly
I love how simple it is to understand the information. How you write and explain everything is extremely helpful to my understanding. As Molly said, The time line you gave through your post was also a great idea.
ReplyDelete