Dr. Alysson Muotri, the reseacher of UCSD, is devoted to finding cures from autism spectrum disorders. For that purpose, he organized collection of stem cells from milk teeth from both autistic and non-affected kids. A so-called Fairy Tooth Kit Collection helps people donating their children milk teeth as they fall out. The campaign has been developing over the social media since 2009, so by now the program has 3000 donors from different countries of the world.
To receive the Fairy Tooth Kit, the parents of a child have to register with the project. The kit was designed to keep stem cells from the tooth pulp alive while tooth is on its way to the laboratory. The kip contains ice packs to keep the tooth cold and a solution to preserve the cells. Teeth fallen out need to be harvested quickly while the cells are still viable.
After coming to the lab, the pulp cells from the collected teeth are turned into induced pluripotent stem cells and are cultivated in a petri dish to form neurons (neural cells) that can be used in the research. By comparing neural cells from autistic kids with cells from unaffected children, the researchers made a few important conclusions.
First of all, they found out that neurons of autistic children can form less synapses (neural connections) compared with neurons of healthy children. When treated with an experimental drug – insulin growth factor – for two weeks in the lab, neurons from autistic children could form the lacking synaptic connections up to the normal levels.
However, this was not the only finding of the research. The researchers tried to get closer to the brain model and studied not only neurons, but also astrocytes – star-shaped glial cells in the brain and spinal cord that are the most numerous in the human brain. Connected to both blood vessels and neurons, these cells provide nutrients to the nervous tissue. Among other functions, astrocytes play an important role in communication to other astrocytes in the brain.
When studied in the lab, astrocytes of autistic children failed to show correct communication, actually this communication was very low. This impelled authors to study the different combinations between normal and autistics neurons and astrocytes. They isolated individual neurons (low density neuronal cells) in the plate on the top of astrocytes for two weeks to see how neurons will be developed.
Combination of normal neurons and normal astrocytes resulted in correct development of the neurons and combination of ASD-derived neurons and astrocytes resulted in immature neurons as one would expect. But combination of normal and ASD-derived neurons and astrocytes brought insights. When normal neurons were grown on autistic astrocytes, they failed to develop normally, while the opposite combination – of autistic neurons on normal astrocytes – brought mature neurons.
This means that genetic changes that underlie autism have not the last word, and the cure for autism still may be found. Though this may take another decade, the doctors are optimistic.