A cutting-edge study at the University of Oxford. Stems cells that had been differentiated into nerve cells were inserted into a special printer, ‘fabricating’ a tissue that can replace damaged tissue in the laboratory.
Every year, 70 million people worldwide fall victim to head injuries caused by road traffic accidents, and sports, workplace or other accidents. Of these, 5 million don’t survive. But sometimes, even those who do pull through — and this also applies to individuals needing brain surgery, or stroke victims, etc. — have to come to terms with more or less extensive brain damage and the lack of effective regenerative treatments for the injured areas.
However, hope is now on the horizon thanks to researchers at the University of Oxford, in the UK, who have found a way, using special 3D printers, to create a kind of biological tissue composed of stem cells that is capable of creating fragments of nervous tissue to be used precisely in these cases.
To go into more detail, the British scientists began with undifferentiated human induced pluripotent stem cells (hiPSCs). They cultured these to make them become two different cerebral cortex cell types, using combinations of growth factors and chemicals capable of guiding the stem cell differentiation. The researchers then inserted droplets containing each of these cell types into the chambers of a 3D printer, which ‘fabricated’ a tissue made up of two layers of cells.
The tissue thus obtained remained intact for two weeks, demonstrating the soundness of its architectural structure.
The laboratory testa are conclusive
But, as reported by the scientific journal Nature Communications, the Oxford researchers didn’t stop there: they attempted — in the laboratory — to transplant the (human) tissue obtained with the 3D printer into mouse brain slices in which a lesion had been created. By doing so, the scientists demonstrated that the 3D tissue was able to integrate easily with the mouse brain tissue, forming connections and branches with it, migrating into it and even giving rise to electrical activity, proving that the transplant had been successful. What’s more, the human cells in the 3D tissue and the mouse cells established connections and exchanged chemical and electrical messages with each other, which is another promising sign from an experimental perspective.
Drug trials are also on the orizon
Studies are now ongoing to find a way to implant the 3D tissue into a human — and no longer mouse — ‘environment’. A long series of further tests will be required, but the goal doesn’t feel unattainable. Among other things, a system like this one could also be invaluable for studying the brain’s activity more closely, as well as its response to injuries and the action of specific drugs. Yongcheng Jin, lead author of the study, said: “This advance marks a significant step towards the fabrication of materials with the full structure and function of natural brain tissues. The work will provide a unique opportunity to explore the workings of the human cortex and, in the long term, it will offer hope to individuals who sustain brain injuries.”