Hi Reddit, We are Sandhya, David and Chan. Our research aim is to design special vessels, known as bioreactors to grow human cells outside the body. Currently, we are trying to grow stem cells that can turn into red blood cells (RBCs).

Blood is essential for medical emergencies, treating certain types of cancer and RBC diseases. >118 million units of blood is collected annually, worldwide, however there is still a global shortage of blood for transfusions. For instance, every 2 seconds, someone in the UK needs blood, but, only 4% of the population regularly donate. Our research vision is to grow RBCs in the lab to address this shortage. We are designing what are known as fluidized bed bioreactors for growing stem cells and maturing them into RBCs. The design of these bioreactors allow efficient transport of expensive nutrients reducing the cost of growing RBC's. Eventually, after clinical trials to ensure quality and safety of the manufactured RBCs we can use them in patients. Please ask us anything about our engineering approaches for RBC manufacture.

Proof: Here's my proof!

Thank you for all the great questions, we will be heading off in the next couple of minutes but we will try and and answer as many questions as we can before that. Please do leave you feedback here https://www.menti.com/alsm1ao6jy3h/0 Thanks again!

Comments: 35 • Responses: 11  • Date: 

Annual-Mud-9879 karma

Hi! This is fascinating. How similar are the red blood cells you grow in a lab to real human blood cells? Is it possible to grow cells that are identical to real red blood cells?

UniversityofBath8 karma

This is very cool research that can impact so many lives! Thanks for the work that you do.

My question is: Is it possible to also differentiate stem cells to other types of blood cells like platelets and white blood cells?

Hello, thank you for the great question! The starting cell type, known as BEL-A cells (developed by scientists at University of Bristol) that we work with, have been succesfully matured into red blood cells that are similar to native red blood cells found in the body - their biological signature and performance (e.g. oxygen-binding capacity) are comparable. Our aim of designing 'bioreactors' to mass manufacture these cells will be followed up with a list of criteria that we will check against to make sure that our bioreactor-produced cells are comparable to native red blood cells.

wise-areola-fungus8 karma

Sorry if this is a bit off topic.

It's pretty cool to see chemical engineeers working on something that is in the scope of biology. Although in today's world cross-disciplinary projects are pretty common. Do some of you have a background in biology or any other department? If so then why did you end up working specifically on this project? And also if you aren't from a biology background then did you have to learn it like in a classroom?

I'm not knowledgeable enough to ask the 'how' questions here but I'd like to ask the what why and when

UniversityofBath9 karma

Thanks for you question! I (Sandhya) am a biotechnologist (so expert in bioreactors) and stem cell engineer. I (David) very much have a background in biology – I did my undergrad in Applied Biology and a Masters in Stem Cells and Regeneration. I chose this project because I was keen to work with stem cells and bioreactors, and because I wanted to contribute to a project that could make a real different to people’s lives and wellbeing. I (Chan) am a (bio)chemical engineer (Chan) and although I had taken a few biochemical modules on how to produce biomass, cells, and proteins in a bioreactor, I had to learn the cell biology of RBCs and the biological process behind it. I have chosen this project because as a biochemical engineer, I enjoy optimisation and the production process, but I always enjoyed medical science, which triggered my interest in this project.

meanderingsquid5 karma

This is very cool research that can impact so many lives! Thanks for the work that you do.

My question is: Is it possible to also differentiate stem cells to other types of blood cells like platelets and white blood cells?

UniversityofBath6 karma

Thank you so much for your kind words and the great question! If we use the right starting cell type, we can theoretically produce any target cell type of interest. For instance, we use red blood progenitor cells, which are what we refer to as 'lineage-committed' - so they can only mature into red blood cells and not other cell types in the blood tissue. However, the technology we are developing could use any starting cell type from the blood tissue - so if we were to use haematopoietic stem cells (not lineage-committed), we could potentially produce other cell types in the blood tissue such as white blood cells and platelets.

allthingsthroughlove5 karma

[deleted]

UniversityofBath10 karma

Thank you for the question, if blood transfusion is the current mode of treatment, then yes our researach will definitely be of help. In addition, for people requiring regular transfusions, the cells we manufacture would theoretically be better in terms of blood type matching and risk of immune rejected (also known as alloimmunization)

Minute-Able4 karma

Why RBC? Is it an easier cell to make or is the demand that high that justifies it?

Does these RBC have blood type? Can they be tailored to fit all blood type?

How important is this bioreactor in the process, as if without it it is impossible to make RBC? Solve one issue of many in the creation process? Lower the cost for "mass manufacturing"?

After this is done, what would be the cost of making one "serving of blood" (sorry I dont know what would be a better word) needed in a hospital setting?

UniversityofBath9 karma

Thank you for your question! Bioreactor technologies are being developed for a variety of cell types and this is an area of active research. There are many challenges with growing any cell type outside the body including red blood cells (RBCs). We aim to manufacture RBCs to address the growing shortage of donated blood globally. Within the different cell types in blood, we are focussed on RBCs since they are the oxygen-carying component of blood and hence, if we can replenish them for a patient who has suffered major blood loss, we can save the patient's life and their body is then able to replenish the other cell types in the blood tissue.

We can manufacture RBCs using existing bioreactor technologies, but these technologies are not yet fully optimized for cost-effective manufacture. Our research focuses on optimizing these technologies (that were developed for other cell types) specifically for cost-effect mass RBC manufacture. Current cost of donated blood is ~£125/unit (it is >£500/unit for rarer blood types) while that for bioreactor-produced RBCs is >£5,000/unit. Our research aims to design better bioreactors to bring down costs closer to that of donated blood.

DrewSmoothington4 karma

Could it be possible to engineer red blood cells that are more efficient than the naturally occuring ones in our bodies? Would the cells you are engineering be identical to natural ones, or more/less efficient?

UniversityofBath6 karma

Thank you for the great question! It would definitely be cool to make extra efficient red blood cells that work way better than the naturally occuring ones! It would be a whole new area of research for blood biologists. However, as engineers, we are currently working with the cells that the biologists have developed and given to us, so the naturally occuring red blood progenitor cells and we are aiming to grow and mature them in red blood cells that would deform in the same manner (essential to allow them to navigate through blood vessels) and they bind and release oxygen in the same manner to naturally occuring ones in our bodies.

Lonely-Row-87263 karma

Is the practice of artificially growing and maturing Stem Cells into RBCs just cutting edge research or something currently doable on large scale?

UniversityofBath9 karma

 Great question, thank you! It is both cutting edge and doable, however, currently it is expensive to mass produce them to be used in the clinic for blood transfusions. We can make a few millilitres in the lab, but existing technology does not support making 'units' of blood in a cost-effective manner (compared to donated blood costs). So you're correct - one of our key research aims is to design a 'bioreactor' technology that will make the red blood cell manufacturing process more efficient and hence cost-effective.

odin9173 karma

is the yield greater than the input? that is, is it possible to get more stuff out of a bioreactor than you put in in such a way that it's viable for large scale use?

UniversityofBath6 karma

Yes, absolutely! It is the key aim of using technologies such as the bioreactor. We start with a small number of stem cells or progenitor that have the capacity to divide and give rise to more stem/progenitor cells, under the right conditions. Once we get enough starting stem/progenitor cells, we then modify the bioreactor conditions to promote their maturation (also known as differentiation) to form red blood cells. Our research aims to identify these best conditions to grow and mature these cells within bioreactors, as well as the starting cell number and final cell numbers we can get from the bioreactor.

PeanutSalsa3 karma

After you grow human red blood cells in the lab, how long before they expire?

UniversityofBath5 karma

The typical shelf life for donated RBCs is up to 42 days. We are currently working on answering this question, but we would expect it to have a longer shelf life as it a pure population of young and pure population of red blood cells.

katzeye0073 karma

So, True Blood then?

UniversityofBath7 karma

We’ve contacted Fangtasia as a potential business partner :)

sh1be3 karma

Will you be growing RBCs that are universal donor or the blood type is random?

UniversityofBath7 karma

Thanks for the question! We currently work with red blood progenitor cells that will give rise to the universal blood type RBCs.