Stem Cells: Mini Superheroes Living Inside of You
What if I told you that one of the greatest innovations in medicine is at work inside of your body right now? In fact, what if I said that this incredible technology has been keeping you alive since before you were even born?
Well, it’s true. Right now, you probably have hundreds of thousands of mini shape-shifters waiting to jump into action from fixing a tiny scratch on your arm to performing neurogenesis, the formation of new nerves, within your brain. No, these little superheroes aren’t science fiction, they’re stem cells!
Crash Course: Intro to Stem Cells
Let’s first address the elephant in the room. What is a stem cell? According to the National Institutes of Health, stem cells are defined as unspecialized cells within the body that have the potential to renew themselves and divide into many different cell types.
Since the first observation of stem cells in 1981, there have been 2 main categories discovered: pluripotent and multipotent.
So what’s the difference?
Pluripotent stem cells have the ability to transform into any cell in the body. These cells form naturally in a ball of cells called a blastocyst during the development of an embryo (hence their nickname as embryonic stem cells).
You can visualize it like a circular egg. In this case, the shell of a blastocyst called the trophectoderm and it will later become the placenta. The blastocoel or blastocyst cavity would be the egg white and the cluster of stem cells is like the yolk. These cells are like the varsity team of stem cells.
Multipotent cells (aka adult stem cells) are like the junior varsity of stem cells. There are 5 types: hematopoietic, mesenchymal, neural, epithelial, and skin. These cells are found in blood from umbilical cords (hematopoietic), fat and bone marrow (mesenchymal), and many other tissues in the body. They usually sit and wait until they are needed to repair any damage or replace other cells. They can still convert into multiple different functions, but not nearly as many as their pluripotent siblings.
At least, so we thought.
In 2006, Shinya Yamanaka, a Nobel Prize-winning stem cell researcher, discovered a way to train these multipotent stem cells as well as regular, differentiated cells to become pluripotent varsity level cells. You would think that this reprogramming would take dozens of chemicals or special machinery operated only by the laser precision of world-class professionals right? It’s just an alteration of 4 transcription factors, also known as Yamanaka factors, done by utilizing a modified virus to introduce these factors into the cell. These are called induced pluripotent stem cells (iPSCs) and they are revolutionizing the medical field.
Harnessing These Superpowers for Good
Alright, we have these talented little blobs that have the ability to turn into anything in the human body. Great. So how does that translate into them being the superheroes that I hyped them up to be? Well, when these potential-packed cells get put into the hands of scientists, their list of applications is endless.
Because stem cells are the foundation of all the cells in your body, they are super useful when studying human development, autoimmune diseases, drugs, and regenerative medicine. As they are the natural fixers in your body, scientists have been working to harness their abilities in order to treat diseases that we had never thought possible.
Hearts In A Dish
Dr. Charles Murry, a researcher from the University of Washington, is making huge discoveries in the field of stem cells as a treatment for regaining cardiac function after a heart attack.
In his research, Dr. Murry discovered that if he took iPSCs and grew them in a petri dish with the right environmental conditions, he could grow clusters of heart muscle cells that actually beat in unison.
Dr. Murry has been able to transplant these cells into cats and guinea pigs who had scarring on the walls of their hearts and rebuild functioning muscle. When he recorded the left ventricular ejection fraction (how much blood is being pumped out with each beat) of each of his trials, he found that within 3 months of the transplant, the ventricular ejection fraction for each subject increased about 22 points, almost as though the damage had never occurred.
Imagine if we were able to grow all different types of cells using iPSCs to treat all kinds of diseases and conditions. Well, you don’t have to. This research is already happening across the globe to restore nerve function after spinal cord injuries, treat autoimmune diseases such as multiple sclerosis, and transplant bone marrow stem cells into patients with blood disorders.
When Worlds Collide: AI Meets Biotechnology
So are you convinced that stem cells are superheroes yet? If not, just wait until I tell you about the bio-bots. Yes, you read that right. Scientists have recently harvested embryonic stem cells from the African clawed frog and coupled them with artificial intelligence to create a new type of robot called a xenobot.
Researchers have been able to take these frog cells, grow them into little spheres of tissue, and shape them using surgical forceps and micro-cautery based on designs created by AI simulations where they are tasked with creating structures to complete the desired function.
Once these clusters are shaped, they start interacting with each other to differentiate into skin cells which form the main structure and mini-heart muscles that grant them mobility.
These mighty little bots are able to self-repair and live for weeks without food or water. They have the capability to work in groups to transport drugs to specific sites within the body and scrape out the plaque within arterial walls.
Outside of the body, they also have the potential to clean radioactive wastes and collect microplastics from the ocean. Because they are not made with traditional materials used in other robots such as steel, these xenobots are much safer and environmentally friendly.
With Great Power Comes Great Responsibility
At this point, stem cells seem pretty awesome. So why aren’t we using them everywhere? Is there some sort of kryptonite that is keeping them from completely changing the game of biotechnology?
Unfortunately, yes.
- Stem cells are unpredictable. There have been cases in the past where doctors inject stem cells into patients that end up differentiating into unforeseen cell types, causing problems in the procedure. They can also travel to unintended areas in the body.
- There are also malignant stem cells that spread cancer throughout the body. It is still unknown how these cells become cancerous, but once they do, it is very hard to eradicate all of them before they multiply and spread.
- Many people have expressed reservations about the morality of stem cell research as one of the main sources is human embryos. Now, with iPSCs, we don’t have to rely on embryos as much, but the technology is still not as efficient and convenient.
Though these limitations are concerning, as we perform more clinical trials and make more discoveries about stem cells, we are getting closer and closer to developing safe and reliable therapies that could potentially impact millions.
Takeaways
- There are 2 types of naturally occurring stem cells: pluripotent and multipotent. Both of which are active during different times in human development and have varying levels of potential.
- Scientists can induce pluripotency in any type of cell, opening the door to more research opportunities.
- Stem cells have a multitude of applications from treating heart disease to creating living robots that, once mastered, can change biotechnology forever.
Thank you so much for reading my article. If you would like to further discuss this topic or hear a little bit about what I am currently working on, feel free to contact me via LinkedIn or email me at nishalerdsuwanrut@gmail.com! ❤️
