Role of Stem Cells:
Human life begins as a single cell called the zygote. This cell divides itself repeatedly. Thus the early growth is multiplicative in nature. By the fourth week of pregnancy, the embryonic stem cells modify into tissue types like epithelial, muscular, nervous, etc.
The tissues so formed lead to the development of vital organs. This kind of growth is known as regenerative growth. The stem cells are a special type of cells that have the ability to grow into any type of cell and form vital organs.
The embryo, the placenta, and the cord blood cells have a good percentage of stem cells. In human adults, the stem cells are mainly formed in the bone marrow. They are also present in the brain and certain muscles. Most adult cells cannot modify but can produce similar cells.
Few examples are skin, hair (epithelial) and liver (hepatic) cells. The liver is the only organ in the human body that could grow again if cut or damaged. The stem cells in the bone marrow are highly crucial and are a must for survival. These cells have the ability to transform as blood cells, connective tissues (cartilage), fat tissues and bones.
Treatment For Life-Threatening Diseases:
The blood cells are responsible for carrying oxygen, carbon dioxide, hormones and nutrients from one region to another. They also help in raising immunity levels and preventing major diseases.
In conditions where the blood cells or the circulatory system gets affected, the survival of the patient becomes a question mark. Few examples are leukemia (the bone marrow is directly affected; blood cancer), sickle cell anemia (the red blood cells can’t carry sufficient oxygen), lymphoma (here the immunity is drastically reduced, affects white blood cells).
Generally, cancer treatment methods like chemotherapy and radiation therapy affect the bone marrow. In such cases a transplant of the marrow or injection of stem cells takes place. The bone marrow transplant is one stem cell therapy treatment in India that is well established.
For bone marrow transplantation, healthy stem cells from the patient or from the siblings of the patient are used.
Source of Stem Cells:
In adults, the stem cells are present in the brain, bone marrow, blood vessels, skeletal muscles, liver, etc. But adult stem cells are not pluripotent, that is, they lose the ability to transform into any type of cell. Adult stem cells can produce blood cells, epithelial cells (for skin and hair), fat cells, etc.
The embryo has the stem cells which have the ability to grow into any type of cell and form vital organs. This is the reason why placenta and cord blood is stored in stem cell banks. As these cells are an exact genetic match, there is a very rare chance of rejection by the immune system of the body.
Scientists now are able to make stem cells in the laboratory, which are known as Induced pluripotent stem (iPS) cells. They take the normal adult cells like the skin cell or blood cell; modify it with genomic techniques so that they behave like embryonic stem cells.
Stem cell treatment has many applications. They can be used for tissue grafting, a method to treat damaged or lost organ. As age increases, the adult stem cells may become less effective and could be replaced by frozen embryonic stem cells. So stem cell therapy treatment could keep the body young and beautiful.
In regenerative orthopedics, stem cell treatment methods have a wide array of applications. As the stem cells have the capacity to form cartilages and bones, they can alleviate pains in knee joints, hip joints, etc. Scientists are exploring options to utilize stem cells for implanting a new joint as in case of knee replacement.
Controversies And Research:
Embryonic stem cells in the placenta and umbilical cord should be obtained with the consent of the mother and the family. Both placenta and cord blood are rich in hormones.
They could be used for various purposes by pharmaceutical companies. Proper storage is costly and important. As of now, the usage of stem cells for the medication (except cancer) is not guaranteed.
The scientific community believes that stem cells might explain the mysteries of evolution and the immune system. In research labs, stem cells are modified artificially to form myocardial tissues and this, if implemented, could be a relief for heart and sugar patients.