I am not sure if this conversation is still active, but I will just leave my (bioengineering) opinion here anyway. I see that the conversation (mainly between AMK and Chris Pearson) has already touched upon some really good points - e.g., pancreas transplantation and getting groups of cells to secrete insulin. The questions raised here are actually very well known within the research community and represent one of the major goals of tissue engineering (https://en.wikipedia.org/wiki/Tissue_engineering).

One of the biggest challenges in the field right now is creating whole organs in the lab (so that in the future we could obviate the need for organ donation from another person). Tissue engineers are able to create mini versions of different organs (”organoids”), but it is still difficult to make them in the right size. Also, cells often require to be grown in some kind of matrix material (e.g. hydrogel), or on scaffolds. This is done to (i) support/constrain/guide cell growth/migration in 3D space and (ii) provide a suitable physicochemical environment for the cells (because they respond to mechanical and biochemical signals). There is still much to know about how different physical parameters (material stiffness, curvature, porosity) and biochemical factors (e.g. proteins) influence the way cells behave. In addition, we also need to consider ways to keep the cells alive in bioprocessing and think about factors like fluid shear stress in the bioreactor.

Another (more recent) tissue engineering approach is 3D bioprinting (https://en.wikipedia.org/wiki/3D_bioprinting). However, researchers are still figuring out ways to print, for example, a whole pancreas or liver. The good news is there are people addressing exactly this issue - look up Jennifer Lewis’s lab at Harvard (https://lewisgroup.seas.harvard.edu/) or Mark Skylar-Scott’s lab at Stanford (https://med.stanford.edu/skylarscottlab.html), for example.

Hope you find the information useful.

Hi Matthew. Remarkable! 3D bioprinting offers numerous possibilities for medicine and biology. I admire the efforts of the researchers who are attempting to print entire organs and tissues with bioinks and living cells.

I wonder how the recipients bodies will respond to these artificial organs. What measures can be taken to ensure that the printed tissues and organs are compatible with the immune system and do not cause rejection or inflammation? Are clinical trials happening yet ?

I wonder how the recipients bodies will respond to these artificial organs. What measures can be taken to ensure that the printed tissues and organs are compatible with the immune system and do not cause rejection or inflammation? Are clinical trials happening yet ?

One of the main strategies to avoid organ rejection is to use cells derived from the patient (autologous cells). For example, cells (e.g. fibroblasts) can be collected and reprogrammed into stem cells (induced pluripotent stem cells, or iPSCs) using genetic modification methods. These iPSCs have the ability to differentiate into almost any cell type in the body. To convert iPSCs into insulin-producing beta cells, a multi-step process will need to be done where the cells are exposed to a combination of growth factors and signalling molecules. 

As far as I know, this type of work is still very much in the research phase. In tissue engineering, the most promising area so far is bone regeneration, so there are quite a few clinical trials for that. But there are definitely many research groups around the world working on engineering solutions for diabetes. This is evident in the number of related publications in recent years:

Generation of iPSC-derived insulin-producing cells from patients with type 1 and type 2 diabetes compared with healthy control
https://www.sciencedirect.com/science/article/pii/S1873506120302592

Recent Advances in the Generation of β-Cells from Induced Pluripotent Stem Cells as a Potential Cure for Diabetes Mellitus
https://link.springer.com/chapter/10.1007/5584_2021_653

β cell replacement therapy for the cure of diabetes
https://onlinelibrary.wiley.com/doi/full/10.1111/jdi.13884

Regeneration of Pancreatic Cells Using Optimized Nanoparticles and l-Glutamic Acid–Gelatin Scaffolds with Controlled Topography and Grafted Activin A/BMP4
https://pubs.acs.org/doi/full/10.1021/acsbiomaterials.3c00791?casa_token=l7JaiF8U9KkAAAAA%3A8DVaDS-5P0IL0wMo5LEVgdAKuSuLRHg3OFc6sfzHmWNnfFOIMUtU8yLcJwCjSksnHUx3gCaARHCZ2q0

Thank you for your valuable input and feedback, Matthew. The authors highlight the immunological and technical hurdles that need to be overcome to guarantee the long-term success and safety of islet transplantation. They state that islet transplantation is a feasible treatment option for type 1 diabetes, but it requires further improvement and refinement in the aspects of donor cell quality and quantity, immunosuppression reduction, and islet engraftment and performance. I am very fascinated and interested by this topic, as I have a keen interest in investigating the possibility of islet transplantation as a cure for type 1 diabetes.