In the body, there are many types of cells that work so that all your organs function properly. However, have you heard of stem cells? In the medical world, stem cells are now a hot topic to talk about, because these cells have ‘special’ abilities and can be a recent breakthrough in treating various chronic diseases.
Stem Cell Definition
Basically, all individuals come from a single cell called a zygote – a combined cell between a woman’s egg and a man’s spe**rm. Then, this cell divides into two, then four cells, and so on. After dividing, the cells will naturally take on their respective roles and responsibilities in the body. This process is called differentiation.
Stem cells are cells that are still ‘plain’ and do not have any function. If you remember the lesson when in school, each network consists of cells that have their own functions. For example, muscle cells that serve to maintain muscle function.
Meanwhile, stem cells are not like other cells. This cell is pure and has not been given any responsibility, nor has it gone through the process of differentiation. In addition, this type of cell has the ability to and can divide as much as possible as needed. Both of these abilities make stem cells considered ‘special’ and can be used to treat a disease.
Stem Cell Types
Stem cells have a wide variety of types. Scientists suspect that every organ in our body has a specific type of stem cell. For example, our blood is created from blood stem cells (also known as hematopoietic stem cells).
However, stem cells are also present at the earliest stages of human development and as scientists grow them, they are called “embryonic stem cells”. The reason why scientists are interested in embryonic stem cells is because the natural task of embryonic stem cells is to build up every organ and tissue in our body during human development.
What is meant is that embryonic stem cells, unlike older stem cells, can turn into almost all hundreds of other types of human cells. For example, blood stem cells can only create blood, but embryonic stem cells can create blood, bones, skin, brain, and so on. In addition, embryonic stem cells are also programmed naturally to create tissues and organs that are not created by older stem cells.
So embryonic stem cells have a greater natural capacity to repair diseased organs. Embryonic stem cells are made from the rest of the embryo from fertility treatments that are still a few days old, made in a cup inside the laboratory, and which will be discarded anyway as well.
Based on differentiated capabilities, stem cells are divided into:
- Totipotent is a cell that can differentiate into all cell types. Included in the totipotent stem cell is a zygote (fertilized egg).
- Pluripotent is a cell that can differentiate into 3 germ layers: ectoderm, mesoderm, and endoderm, but cannot be extraembryonic tissue such as the placenta and umbilical cord. What includes pluripotent stem cells is embryonic stem cells
- Multipotent is a cell that can differentiate into many cell types. For example: hematopoietic stem cells.
- Unipotent is a cell that can only produce 1 type of cell. But unlike non-stem cells, unipotent stem cells have properties that can renew or regenerate themselves (self-regenerate / self-renew).
Stem cells are found in various tissues of the body, so stem cells are divided into several based on the origin of the cell:
- Zygote. That is at the stage shortly after the spe**rm meets the ovum
- Embryonic stem cell is a cell taken from the inner cell mass of a blastocyst (embryo consisting of 50 ¬ 150 cells, approximately the 5th day after fertilization). Embryonic stem cells, usually obtained from the remaining embryos that are not used in IVF (in vitro fertilization). But now a technique has been developed embryonic stem cell retrieval that does not harm the embryo, so that it can continue to live and grow. In the future this may reduce the ethical controversy over embryonic stem cells.
- Fetus. A fetus is a development in the embryonic phase and before birth. Fetuses can be obtained from abor**tion clinics.
- Umbilical cord blood stem cells, ie cells taken from the blood of the placenta and umbilical cord as soon as the baby is born. Stem cells from umbilical cord blood are a type of hematopoietic stem cell, and some classify this type of stem cell into a**dult stem cells.
- A**dult stem cell. i.e. Cells taken from older tissue, among others: Bone marrow.
There are 2 types stem cells of the bone marrow include:
- Hematopoietic stem cell. Aside from umbilical cord blood and from the bone marrow, hematopoietic stem cells can be obtained also from the blood edge.
- Stromal stem cell or also called mesenchymal stem cell.
Other tissues in a**dults:
Other tissues in a**dults such as in: central nervous structure, adiposity (fat tissue), skeletal muscle, pancreas. The a**dult stem cell has plastic properties, meaning that in addition to differentiating into cells corresponding to the original tissue, a**dult stem cells can also differentiate into other tissue cells. For example: neural stem cells can turn into blood cells, or stromal stem cells from the bone marrow can turn into heart muscle cells, and so on.
General properties of stem cells
Stem cells are cells that are not / have not specialized that have 2 properties:
Ability to differentiate into other cells (differentiate).
In this case stem cells are able to develop into various types of mature cells, for example, nerve cells, heart muscle cells, skeletal muscle cells, pancreatic cells, and others.
The ability to renew or regenerate itself (self-regenerate / self-renew).
In this case the stem cell can make a copy of the cell that is exactly the same as itself through cell division.