Functional brain cells – astrocytes – play an important role in normal brain function. The star-shaped glial cells are also known to play a role in the development of neurodegenerative diseases such as ALS and dementia. In order to study and better understand neurodegenerative diseases, researchers need to study human astrocytes. However, obtaining those cells is a complicated, expensive, and time consuming process.
Astrocytes can be grown in the lab from embryonic stem cells, but the process takes months. Now, researchers at Lund University in Sweden have developed a new technique that speeds up the process considerably. Instead of months, large quantities of human astrocytes can be grown in the lab in just 1-2 weeks.
Previous attempts to grow human astrocytes from embryonic stems cells mimicked development in human embryos and was highly complex. Lead researcher of the study Henrik Ahlenius and his team used viruses to activate genes in embryonic stems cells to greatly speed up the process – specifically causing overexpression of the transcription factors SOX9 and NFIB. The astrocytes they grew using their new technique are very similar to those found in adult humans in terms of appearance, function, and genetic profile.
“This means that it is now easier than before to study the role of astrocytes in various diseases”, said Ahlenius.
The astrocytes generated by the team have already been used to study a rare disorder of the nervous system called Alexander disease – a disease that involves destruction of the fatty covering of nerve fibers (myelin). The researchers introduced a mutation into embryonic stem cells using the CRISPR-Cas9 gene editing tool and used their new method of generating astrocytes to change both healthy and mutated stem cells into astrocytes.
After studying both groups of astrocytes, the researchers identified defects in the mutated stem cells which are known to be present in individuals suffering from Alexander disease.
The team plans to use their new technique to grow large quantities of astrocytes to study age-related neurodegenerative diseases such Alzheimer’s Disease and dementia and investigate the role astrocytes play in the development and progression of those diseases.
The study – Rapid and efficient induction of functional astrocytes from human pluripotent stem cells – has recently been published in the journal Nature Methods.
Image source: Wikimedia Commons, CC BY-SA 3.0 – By Bruno Pascal