Stem Cells 101 🔬
By: Sayyida Hashim
Tags: Women in STEM, Stem Cells, Stem Cell Research, Stem Cell Therapy, STEM

Stem Cells 101 🔬

When we were young, we were open to literally every career choice there is on the planet. Doctor, engineer, waterslide tester, you name it. As we grew older, we started to narrow out our career options and be more specific with what we want to be, and these options were influenced by the environment they live in.

The same goes for stem cells, cells with the ability to self-renew (make more copies of themselves) and differentiate (change into other cell types). Perplexed? It’s okay because we are about to dive into all things everything STEM CELLS!

Young cell? Well, not exactly.

Essentially, stem cells are just unspecialized cells that have the potential to develop into other specialized cell types like muscle cells, nerve cells and many others. They don’t really have a specific function; they just chill and multiply till the time has come to specialize.

Then, why do we even have stem cells?

Stem cells have great potential in the field of medical research but let’s see what role they actually play in our body.

Replacing specialized cells : Our body is constantly losing cells, but have you ever wondered why it never runs out? Well, you’ll have to thank stem cells for that! Stem cells, with the help of external and internal signals, transform into specialized cells and replaces damaged or dead cells.

: Our body is constantly losing cells, but have you ever wondered why it never runs out? Well, you’ll have to thank stem cells for that! Stem cells, with the help of external and internal signals, transform into specialized cells and replaces damaged or dead cells. Producing new cells for the body as it grows: Even if we supposed that we aren’t losing cells, we can’t deny that our body is growing! To grow, we obviously need more cells and that’s where stem cells come in. Their ability to differentiate and make copies of themselves really does come in handy for this.

Where though?

Hmm… Stem cells are cool and all but where do they even come from?

Here are the all-time favourite spots of these fascinating cells (depending on the type!)!

Embryonic stem cells (Image from Pixabay)

Embryonic Stem Cells : These stem cells are found in the blastocyst stage of a human embryo. Think of the blastocyst stage as a ‘hollow ball’ of cells. It contains some cells on the interior known as the inner cell mass (ICM), which eventually gives rise to the development of the foetus. The cells of ICM are embryonic stem cells and it can develop into almost all cell types.

: These stem cells are found in the stage of a human embryo. Think of the blastocyst stage as a ‘hollow ball’ of cells. It contains some cells on the interior known as the (ICM), which eventually gives rise to the development of the foetus. The cells of ICM are embryonic stem cells and it can develop into almost all cell types. Somatic Stem Cells (Tissue-specific stem cells): Our body has ALOT of stem cells, and these stem cells that are found throughout the body are known as somatic stem cells. They can develop into a limited number of cell types.

A ‘lil bit about Potency!

Remember how I mentioned about stem cells’ ability to change into other cell types? Well, the extent of this ability to differentiate varies in different cells and we can call this the cell’s potency.

On the basis of potency, we can divide stem cells into the following:

Totipotent (AKA Omnipotent) Stem Cells : These types have the highest potency → they can turn into ANY of the 220 cell types in the entire body, including placental cells 😮 An example of this is the zygote, the product of the fusion of the egg and sperm cell.

: These types have the highest potency → they can turn into ANY of the 220 cell types in the entire body, including placental cells 😮 An example of this is the zygote, the product of the fusion of the egg and sperm cell. Pluripotent Stem Cells : These types can turn into any cell in the body EXCEPT the placental cells. An example of this is embryonic stem cells.

: These types can turn into any cell in the body EXCEPT the placental cells. An example of this is embryonic stem cells. Multipotent Stem Cells (AKA adult stem cells!): These types can turn into a limited number of cells. For example, haematopoietic stem cells can only turn into cells found in the blood.

How would you react to the idea of inducing specialized cells to become PLURIPOTENT stem cells? Sounds crazy, right? Well, to know if it is fantasy or not, you are going to have to check out the next section! 😉

Spoiler: It is possible, Induced Pluripotent Stem Cells (and to enjoy history).

You read that right, it is possible! Induced Pluripotent Stem Cells (iPSCs) are specialized cells that have been reprogrammed back (wild, I know) to a pluripotent state. iPSCs opened a new door to stem cell research and completely changed how we thought of mature cells.

I’m not the biggest fan of history but here is the history of iPSCs for your information!

A history class from your favourite professor!

In 2006, Shinya Yamanaka produced the first-ever iPSCs from mouse embryonic fibroblasts 🐁 by inserting four specific genes into its nuclei. The following year, Yamanaka announced his success in deriving the first ever iPSCs from HUMAN 👨 fibroblasts. This news came as a pleasant surprise for everyone because this meant that we could obtain stem cells without the controversial use of human embryos, which was mostly looked down upon for ethical reasons. Yamanaka went on to receive the Nobel Prize of Medicine in 2012 and other major awards.

Now I know what’s running through your mind, ‘This seems cool but… why do it in the first place?’ iPSCs could have numerous benefits and uses for us humans, some of which are listed below:

Regenerative medicine 💉: Regenerative medicine is the science of restoring damaged tissues and organs using stem cells. It is otherwise known as stem cell therapy.

💉: Regenerative medicine is the science of restoring damaged tissues and organs using stem cells. It is otherwise known as stem cell therapy. Research 🔬: With iPSCs, scientists can study how a disease unfolds and sometimes, they model these diseases in the lab to get a better understanding. This could play a major role in discovering the cure for major diseases!

🔬: With iPSCs, scientists can study how a disease unfolds and sometimes, they model these diseases in the lab to get a better understanding. This could play a major role in discovering the cure for major diseases! Ethical edge over embryonic stem cells 👼: The usage of embryonic stem cells is a very controversial topic due to its ethical considerations. iPSCs are here to change all of that since they aren’t obtained from an unborn baby. This gives them an ‘ethical edge’ over the previously-used embryonic stem cells!

👼: The usage of embryonic stem cells is a very controversial topic due to its ethical considerations. iPSCs are here to change all of that since they aren’t obtained from an unborn baby. This gives them an ‘ethical edge’ over the previously-used embryonic stem cells! Avoidance of immune rejection 🏥 : Since iPSCs can be derived from the patient’s own body, there is little chance of immune rejection, which makes it better for stem cell therapy.

Induced Totipotent Stem Cells?

When I was reading about iPSCs and their immense possibilities, a question that kept running in my mind was about totipotent stem cells. Since iPSCs have a lot of benefits due to their potency, why couldn’t we do the same to induce totipotent stem cells? After all, they had a greater level of potency, enabling us to create even more disruptive innovation.

Well, the cool part is that though they are not here yet, stuff is happening in the labs! Know it all from some articles, check them out 👇