Thanks to the miracle of stem cells, scientists will soon be able to mass produce red blood cells for medical use. And that’s very good news for everyone.
Red blood cells are little iron-rich bundles of life that do the important legwork of getting your body’s crucial oxygen supply from the alveoli of your lungs to each and every living cell in your body.
Think of them as being like the truck drivers that replenish every grocery store in the country. Or maybe update that analogy: red blood cells are kind of like Amazon delivery drones, delivering their product (oxygen) to each and every house in the country (or cell in the body).
Given how important these little guys are, it’s no surprise that a host of life-threatening medical problems can result when something goes wrong with their proper functioning. There are any number of ways that you can run into trouble as the result of a shortage of oxygen caused by a failure of your red blood cell infrastructure, and bleeding to death is only the most obvious one.
For example, consider aplastic anemia, a condition in which the patient’s bone marrow doesn’t produce enough red blood cells to cover the needs of the body. Or haemophilia, a condition involving lack of clotting factors in the blood — many haemophiliac patients have relied on blood transfusions to help with the condition.
But people donate blood, right? So what’s the big deal with being able to create an artificial supply of red blood cells? Are people not donating enough?
It turns out blood donation rates are doing just fine. But there’s a technical issue that comes afterwards, once you’ve got all the donated blood: how do you coax the donated blood cells into propagating? In other words, how do you take a small amount of blood and turn it into more blood? It turns to be very difficult.
To get around this, scientists came up with another source for blood: stem cells.
You’ve probably heard of stem cells before, and might have wondered what they are. To get the idea, first think of regular cells. They’re usually specialised: a heart cell looks very different from a skin cell, and a neuron in your brain has a very different lifestyle from, say, a white blood cell in your circulatory system.
Usually, if one of these specialist cells divides to create new cells, the new ones will share the same specialty of the parent cell. In other words: once a cell line has specialised, its specialty is locked in.
But that’s not true of stem cells, and this is why they’re so special: an individual stem cell could give rise to cell lines from any of the specialties. It could create a line of skin cells, a line of brain cells, and yes: even a line of red blood cells.
Using stem cells to create red blood cells is not a new idea. But until now, there’s been an upper limit on how many red blood cells a given stem cell can churn out — usually about 50,000. In terms of blood volume, that is a very small amount of blood. For example, consider the fact that a typical blood bag in a hospital will have about a trillion red blood cells.
But now, scientists at the University of Bristol have figured out a way to immortalize the stem cells used for creating new red blood. As a result of this, they can now use stem cells to produce red blood cells by the litre. And as an added plus, this method eliminates the contamination risk that often comes with donated blood.
This work is still in the early stages. But clinical trials are scheduled for later this year. Hopefully you’ll never need it, but if you do, then one day you might have artificial blood flowing through your veins.