Happy November y’all! With Halloween and Bonfire Night all gone for another year, the countdown to Christmas is on! But the penultimate month of 2016 has arrived and so comes with it the penultimate Cellfie of the Month for 2016!
In October’s Cellfie of the month, we took it back to basics looking at my embryonic stem cells and their raw beauty. If you missed it you can find it here. This time it’s going to get a bit more up close and personal by sharing with you some of my phase contrast images!
But firstly, I want to introduce to you phase contrast microscopy! Normally when you look down the microscope at some cells they are quite difficult to spot and there is very little detail. This is because the cells themselves, all their internal components and the surrounding media absorb similar amounts of light making each part almost invisible. But this is where phase contrast microscopy comes in! It takes advantage of those tiny, tiny differences in light absorption and turns them into brightness variations on the image making each cell and the components within each cell much easier to see, as you can see when you compare the image in my previous Cellfie of the month post to this one:
Embryonic stem cells grow in colonies like this one and each of those colonies are made up of hundreds of cells. Normally only a well trained eye could notice all the cells making up a colony under a normal light microscope, but using phase contrast microscopy, we can reveal the typical cobblestone morphology of embryonic stem cell colonies to the world!
Let’s take an even closer look!
Using phase contrast microscopy and looking at my cells under a higher magnification, we can see even more detail! So, embryonic stem cells have several unique characteristics – they express pluripotency markers like OCT4, SOX2 and NANOG like I’ve shown here, they grow in colonies with a cobblestone morphology and they also have a high nucleus to cytoplasm ratio!
Broadly speaking, cells are split up into two areas – the nucleus and the cytoplasm. The cytoplasm is the area where proteins are made and waste is removed, whereas the nucleus holds all your DNA and is where any changes in gene expression happen! But as far as embryonic stem cells are concerned, the majority of the cell is taken up by the nucleus with a small ring of cytoplasm around it, hence the high nuclear to cytoplasmic ratio, as you can see here:
The red circle is showing the outline of one of the cells in this particular colony, whereas the yellow circle is showing the outline of the nucleus, so you can see that most of the cell is made up of nucleus! And you can probably see that in all the other cells around!
Slowly, this Cellfie of the Month series has been showing you some of the characteristics that make an embryonic stem cell, an embryonic stem cell! Take a look back at my older posts but hopefully you now know that:
- Embryonic stem cells are pluripotent
- Embryonic stem cells express pluripotency markers like OCT4
- Embryonic stem cells express pluripotency markers like TRA-1-60 on their surface
- Embryonic stem cells can make any cell type in your body called differentiation
- Embryonic stem cells can make identical copies of themselves called self-renewal
- Embryonic stem cells grow in colonies with cobblestone morphology
- And finally, embryonic stem cells have a high nuclear to cytoplasmic ratio
And there is plenty more where they came from! If you want to know more, please get in touch I would love to chat to you about stem cells 🙂