Red blood cells are responsible for bringing oxygen to every corner of your body and take along with them wastes. Red blood cells have a tough job squeezing through tight passages which shortens their lifespan to 4 months.
New red blood cells are replaced from stem cells. Stem cells are special kinds of cells that can become any type of cell. Our other cells divide into exactly the same kind of cell like skin cells will divide into skin cells, etc.
That’s why embryos grow from one fertilized egg cell into a fetus with trillions of cells that are specialized to become tissues for the skin, brain and muscles and organs. Stem cells can also be a replacement for damaged or worn out cells like red blood cells.
Scientists are excited to use the amazing abilities of stem cell therapy to replace or repair tissues damaged by diseases or accidents which will heal the body on its own. Scientists are now putting specialized cells to work in repairing damage that can make permanent disabilities history.
The marrow inside the bone is where blood stem cells divide and reproduce. They morph into either blood cells, different types of white blood cells and others remain as stem cells. These are specialized cells that cannot transform into another kind of cell other than blood.
Pluripotent stem cells can transform into any type or kind of cell in the body and are known to be generalized stem cells. These cells also known as embryonic cells that were originally from embryos, where they are taken in the first few days after it has been fertilized. In this stage, these two cells divide into identical cells with potential to become any type of cell. After three to five days however, these cells begin to become specialized transforming into muscle, stomach, brain cells, etc., and become limited.
When babies are born, most of their cells are specialized with their own function and use like muscle, blood cells, etc. Among these cells are also adult stem cells that can’t transform into any other type of cell, but can replace different worn out cells if needed like the ones in the marrow where blood cells come from, the ones in the brain, gut and heart.
The embryonic stem cells are the most useful among the others because it is more flexible compared to adult stem cells, which are rarer and difficult to extract from the tissues. But embryonic stem cells too are difficult to obtain because that would mean destroying an embryo which is controversial.
But now scientists have found a better way when it comes to stem cells.
Shinya Yamanaka found that specialized cells can be reverted back into stem cells back in 2006. A scientist and doctor in Kyoto University persuaded mature cells to revert to stem cells. By inserting genes of a specific set, the cells became like embryonic cells where it is called induced pluripotent stem cells.
This discovery made way for great possibilities over adult and embryonic stem cells like – It is easier to harvest as starter cell type can be used, it can become any type of cell like embryonic cell, and can treat patients using their own tissues. This means that would match the patient genetically and would not be rejected by the body.
Yamanaka’s research is now being used by scientists all over the world as a guide to create their own procedure of induced pluripotent stem cell. This research gave way to many possibilities like learning how certain cell types die, or allow small batches of these cells to be exposed to medicine where different types of drugs can now be tested safely.
Anne Cherry from Harvard uses stem cells to study the rare genetic disease Pearson syndrome where the bone marrow stem cells can’t make red blood cells which results in early death to sufferers.
Cherry started by using skin cells taken from a girl with the disease and turning them into stem cells by adding genes. The cells later on started to behave like embryonic stem cells as planned. She is now trying to persuade the stem cells to turn into blood cells, then learn how the disease Pearson syndrome kills these cells.
Cherry’s goal is to create healthy blood stem cells from the donated skin cells, and return it to the donor’s body to return her to normal and dismiss the need for blood transfusions. These will also be safe as the cells were taken from the donor which means there is no risk of her body rejecting the new cells as it came from her.
Neuroscientist Iqbal Ahmad from University of Nebraska Medical Center is studying how to use stem cells to restore eyesight to people who lost them to glaucoma.
Ahmad is working on a solution to place new retina cells from induced pluripotent stem cells in the eye to replace the dead ones. He starts by taking adult stem cells from the cornea that covers the front of the eyes and coax them to transform into nerve cells. He places the cornea cell beside an embryonic stem cell separated only by a mesh-like membrane where the cells can still communicate. Cells send signals to one another where other cells respond. The procedure overtime will turn the cornea cell into different types of cells like nerve cells.
The team of Ahmad used this procedure on lab mice that lost their sight to glaucoma. The nerve cells migrated to the retina which replaced the dead nerve cells. This proves that the procedure can in the future help restore sight.
Not all procedures require the use of stem cells and only require the chemical communication from cell to cell.
Nick Jeffrey, a veterinary neurologist from University of Cambridge, England, used cells harvested from the back of the nose of dogs to help repair damaged spinal cord connections.
When the spinal cord is damage or severed, it can lead to inability to move, paralysis and loss of sensation.
Jeffrey believes that stem cells are to replace missing cells, where as in spinal cord injuries, it is more of the nerve being severed.
Nerves called axons run along the spine, and when this is damaged, the axons can be cut or severed. This is where the research of Jeffrey comes in, where they remove cells from sinuses of dogs, where these particular cells encourage nerve cells to grow new axons.
They then grow these cells in their lab to create a large enough batch that can be injected into the spinal cord of the dogs. This procedure is monitored for several months where the dogs are returned to the lab to be tested out on a treadmill. The results showed that the procedure helped the dogs improve over time; but it’s still not a perfect cure as the nerves didn’t reconnect with the brain. It reconnected only several portions of the spine.
These developments in the study of stem cells indicate a bright medical future just a few years from now.