Stem cell diffrenciation diagram

Cells are living things that can be independent like bacterial cells, yeast cells or an amoeba or they can cluster together and take on different jobs to make a multi-cellular creature like a human, chicken, mushroom or tree.  

Within a multi-cellular creature, different cells exist that look very different (if you’ve got a good microscope) and do very different things. They’re about 1/100 to 1/10 of a millimetre in size so you can’t see individual cells with the naked eye. Skin cells look different to blood cells, red blood cells look different to white blood cells and there are different types of white blood cells that do different jobs as part of our immune system. Cells that look different through a microscope or that do different things are given different names by researchers. For example: macrophages are cells involved in inflammation and wound healing – they start off as monocytes, happily whooshing around in our blood, but when skin is wounded, they stick to the damaged area and become macrophages that can help fix the damage. Fibrocytes are skin cells that are involved in scarring (fibrosis) and making collagen. Keratinocytes are skin cells that make lots of keratin, a skin protein that doesn’t work properly for many people with epidermolysis bullosa simplex (EBS). Researchers call skin cells ‘epithelial cells’. These are the cells that are involved in making our skin and the layers that cover our internal organs and the insides of our breathing pipe (windpipe or trachea) and food pipe (oesophagus).

Some potential treatments for EB involve growing skin cells in a laboratory.

Researchers sometimes put new treatments directly onto cells grown in a laboratory to see how (or if) they might work before using them on an actual living creature. This is easier, cheaper, safer and reduces the use of animals in research. However, the results might not be quite as useful for patients because cells in a dish are often a little bit different to the ones inside us so may behave differently. It’s also easier to apply a treatment directly to cells in a dish than to get a medicine to them when they are part of a living human body so researchers must consider how their medicine will get to the right cells as part of developing a treatment that works.

Some potential EB treatments are based on stem cells. These are a specific type of cell that can transform itself into other types of cell. Treatments can use autologous stem cells which come from a person’s own body or allogeneic stem cells which come from somebody else. Stem cells are often taken from bone marrow but can come from other parts of the body.


Image credit: Stem cell differentiation, by Haileyfournier. Licensed under the Creative Commons Attribution-Share Alike 4.0 International license.