This is the second in our mini-series of reports from the 2013 Cheltenham Science Festival. In this post, Tasch Mehrabi reviews the session: ‘Controlling the Mind and Slicing the Body with Light’.
In this talk Mark Lythgoe, one of the festival’s co-founders, transported us back to a working lab via Skype where Angela, a working scientist, showed us how to make a mouse embryo transparent. An embryo can be made to emit light by inserting bioluminescence genes into the chromosomes of mice cells. However, when deeper organs emit light we cannot see it from the outside. In order for us to be able to see what’s going on beneath the skin the organ has to become transparent. As Angela illustrated, a process called ‘optical clearing’ can be used to do just that. Optical Projection Tomography is then used to create detailed 3D images of the tiny mouse embryo.
Next, Amit Jathoul outlined his current research focus of bioluminescence. He takes genes from coral and jellyfish and inserts them using a virus into the chromosomes of mice. Though research currently remains restricted to the rodents, the potential applications for medicine are significant. For example, the technology could be used to light up cancer cells, enabling researchers to identify the efficacy of particular anti-cancer drugs.
Light emitting organs are not, however, always ideal. Jathoul reiterated the problems with visualising organs deep within an organism. The light often scatters and the images aren’t clear. He uses an alternative innovative method to create detailed 3D images of deeper tissues. This involves inserting the same bioluminescence genes into particular organs; these glowing organs however then also produce pulses of ultrasound. These pulses can be detected and used to create intricate 3D images of, for example, the vascular system – amazing!
Clare Elwell, a medical physicist from UCL spoke of another problem with light. Her team are more focussed on shining light beams through an organism, rather than the making them bioluminescent. Infra red light, she said, is able to pass through bone much easier than normal white light. Her team look at infant’s brains, as their skulls are much less dense than full-grown adults. They created a head-cap that can be comfortably placed on top of babies’ heads in order to study their brain activity. The head-cap emits the infra-red light allowing researchers to observe the oxygen changes in the brain. When a particular part of the brain is stimulated, there is an increase in oxygen levels.
This has interesting clinical applications. One example is in the study of brain activity of children who have a higher predicted probability of developing autism due to their genes. Children without autism exhibited increased brain activity when shown images of an actress singing ‘itsy bitsy spider’. High-probability autistic children did not show any such increase. With further research this approach could be used to identify children with autism at a much earlier age than is currently possible.
Her team carried out a similar study at the Keneba field station, Gambia, funded by the Bill & Melinda Gates foundation. Here, however, focus was on identifying how malnutrition in a child’s first 30 days of life may influence brain development. Interestingly, despite cultural and environmental differences, Gambian babies responded in a very similar way to British babies to the actress singing! Further applications for this research include studying muscle activation in Olympic athletes, tracking recovery after stroke and other ageing related degenerative diseases.
Image credit: FastLizard4, via flickr.