The development of an artificial liver has been of prominent interest, as liver disease is the fifth biggest cause of deaths in the UK. Acute liver failure (ALF) in children is a life-threatening condition. The prognosis of ALF is generally poor and medical intervention relies on a liver or hepatocyte transplantation if the native liver is unable to recover. The major limitation of the technique today is the availability of donor organs. There have been limited clinical advancements in the treatment of ALF utilising novel regenerative techniques, such as the use of embryonic stem cell techniques to induced pluripotent stem cell-derived hepatocytes. The use of human bio-compatible scaffolds to grow liver type/functional cells is increasing and the main challenges in translating advances in basic science of cell therapy into the clinic has been determining the best route of delivery, the rapid elimination of transplanted cells by the recipient, poor engraftment and proliferation of transplanted cells within the liver.
Researchers at Kings College London, Anil Chandrashekran (pictured right) and Anil Dhawan (pictured below), examined the use of methylcellulose as a scaffold to obtain liver-organoids. They cultured hepatocyte and MSCs in the presence of methylcellulose and growth factors and tested the ability of organoids to produce albumin and detoxify ammonium chloride, in optimally cultured conditions describing their research in BioInsights December 2018.
Mesenchymal stem/stromal cells (MSCs) can be easily cultured from adult bone marrow and full-term umbilical cord (blood or the Wharton’s jelly) and have been isolated from muscle connective tissue, adipose tissue and in some circumstances peripheral blood. Currently novel scaffolds are under scrutiny for the unmet need to use organoid-based product suitable for transplantation in ALF, this until the patient receives a liver transplant or recovers.
Hepatocytes fractions were collected, treated and cells were frozen in cryovials and cryobags using a Planer controlled rate freezer before storage at -180°C vapour phase nitrogen freezers. The MSCs were isolated from Wharton’s jelly of umbilical cords obtained following caesarean section deliveries. Once cell cultures were established, they were expanded, quality controlled and cryopreserved
The study showed that methylcellulose, an inert semi-solid media more suitable for clinical use than current products, could be utilised as a scaffold to establish liver-organoids that resemble liver structure and function. And they say the suitability of using methylcellulose towards clinical grade expansion of organoids is highly compelling. Further optimisation and scaling up of the process is underway.
Improvements to hepatocyte transplantation have been made by encapsulating hepatocytes with alginate beads which eliminates the need for immunosuppressants. More recently, bio-fabrication techniques have been developed using 3D plotting with methylcellulose and alginate. MSCs cultured in these 3D scaffolds retained viability and differentiation properties and so taking these techniques together it should be feasible to establish organoids in methylcellulose, as done here and then encapsulating the resulting organoids in alginate-methylcellulose 3D scaffolds. The organoid culture system established is thought highly applicable in the treatment of ALF but might also be well suited to drug screening and disease modelling.
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Read article: Methylcellulose as a scaffold in the culture of liver-organoids for the potential of treating acute liver failure
Planer freezers: Medium sized control rate freezers