Understanding Stem Cells and Challenges in Clinical Use
The human body is filled with trillions of different cells which are diverse in both form and function. For instance, blood cells deliver oxygen to metabolically active tissues while nerve cells transfer electrical impulses. Muscle and heart cells contract, and skin cells form a protective barrier around the body. Stem cells, however, differ from these specialized adult cell types since they have no specific shape or function. Despite this, all cells in the body, specialized or not, have the exact same sequence of DNA. Different cells such as brain cells or muscle cells exist since different genes are expressed. Stem cells are unique in that they can become a variety of specialized cell types.
The phrase “stem cell” is a general term to distinguish unspecified, undifferentiated cells that are defined by two key properties. First, they are self-renewing, meaning they divide to make identical copies of themselves. Second, stem cells can differentiate into any specific cell type in the human body, such as heart or skin cells. The human body has specific mechanisms to regulate these two abilities of stem cells and control when and where they are needed, such as for tissue regeneration and repair. Because stem cells are able to become any tissue in the human body, scientists have been researching different methods by which stem cells can be used to make advances in medicine and therapy.
The phrase “stem cell” is a general term to distinguish unspecified, undifferentiated cells that are defined by two key properties. First, they are self-renewing, meaning they divide to make identical copies of themselves. Second, stem cells can differentiate into any specific cell type in the human body, such as heart or skin cells. The human body has specific mechanisms to regulate these two abilities of stem cells and control when and where they are needed, such as for tissue regeneration and repair. Because stem cells are able to become any tissue in the human body, scientists have been researching different methods by which stem cells can be used to make advances in medicine and therapy.
Image Source: Science Photo Library - ZEPHYR
Before making clinical advancements with stem cell research, it is important to distinguish between the two main types of stem cells: pluripotent and multipotent. Pluripotent stem cells (PSCs) are cells that compose an embryo and have the ability to differentiate into any type of cell in the body. Multipotent stem cells (MSCs), however, are limited in their potency power as they can differentiate only into cells of a given germ layer— a germ layer is a primary layer of cells formed during early development that gives rise to either the inside, middle or outside of your body. When a person develops from an embryo, their stem cells have the greatest potential of differentiation. However, as growth and development continues, the entire organism’s cells lose potency as its three germ layers are established; PSCs become multipotent stem cells, which are characteristic to cells of a given germ layer. Because pluripotent stem cells exist in an earlier developmental stage than MSCs and have the ability to become any specialized cell type, PSCs are of better potential use to researchers.
Though a promising field for clinical progress, stem cell research faces serious challenges in becoming mainstream. Though researchers hope to one day be able to regrow missing or damaged organs and limbs in patients, physically performing this is not an easy task. Just because PSCs can turn into a specific cell type doesn’t mean scientists would be able to make the cells transform at will. If we differentiate stem cells into the wrong cell type, we may also run the risk of growing a tooth where a heart should be. Furthermore, the use of PSCs for clinical purposes is a morally-controversial topic. Because the only method of obtaining PSCs is by destroying embryos, many who believe that life begins at conception don’t believe stem cell research should be funded.
Given the challenges faced using PSCs, scientists are shifting their attention to MSCs. Although their potency power is less than PSCs, this very restriction to differentiate into cells of one germ layer allows researchers more consistency and predictability in what cell types they can differentiate MSCs into. One of the most successful and common fields of stem cell therapy concerns MSCs called hematopoietic stem cells, which can differentiate into any blood cell type.
Though a promising field for clinical progress, stem cell research faces serious challenges in becoming mainstream. Though researchers hope to one day be able to regrow missing or damaged organs and limbs in patients, physically performing this is not an easy task. Just because PSCs can turn into a specific cell type doesn’t mean scientists would be able to make the cells transform at will. If we differentiate stem cells into the wrong cell type, we may also run the risk of growing a tooth where a heart should be. Furthermore, the use of PSCs for clinical purposes is a morally-controversial topic. Because the only method of obtaining PSCs is by destroying embryos, many who believe that life begins at conception don’t believe stem cell research should be funded.
Given the challenges faced using PSCs, scientists are shifting their attention to MSCs. Although their potency power is less than PSCs, this very restriction to differentiate into cells of one germ layer allows researchers more consistency and predictability in what cell types they can differentiate MSCs into. One of the most successful and common fields of stem cell therapy concerns MSCs called hematopoietic stem cells, which can differentiate into any blood cell type.
Featured Image Source: swiftscientist
RELATED ARTICLES
|
Vertical Divider
|
Vertical Divider
|
Vertical Divider
|
