By Vera Kho
Last summer I visited India for three weeks, which was absolutely a great experience. However, I was in constant fear of all the stray dogs that walked around, because we were told by the GGD that dogs – and cats, monkeys and bats as well – could carry the rabies virus. If bitten, scratched or even licked by an infected animal you need an antidote within 24 hours, or you will die a gruesome death.
The rabies virus is able to infect the central nervous system and can thus bypass the blood brain barrier. It does so by interacting with the acetylcholine receptors at neuromuscular junctions, which allows the virus to enter a peripheral nerve cell. From there on, the virus reaches the central nervous system and eventually the brain. This can cause inflammation of the brain, partial paralysis or uncontrolled movements, but also anxiety, confusion or loss of consciousness.
We as researchers can learn a great deal from viruses. In the case of the rabies virus, it can teach us how particles can enter the brain without interference of the blood brain barrier. In a recently published article by Lee et al. (2017) gold nanorods that had shapes similar to the rabies virus particle were synthesised. These mimicked the glycoprotein layer on the envelope of the rabies virions. The nanorods were injected in mice with brain tumours and stimulated with near infrared lasers: a form of photothermal therapy, resulting in the death of cancer cells and shrinkage of the tumour. These nanoparticles could be the key to a successful therapy for brain gliomas, which are usually very hard to treat with drugs due to the blood brain barrier.
It is amazing what we can learn from other species and how we can use their means to devise and create a (curative) therapy for all kinds of diseases.
Lee C, Hwang H, Lee S, Kim B, Kim J, Oh K et al. Rabies Virus-Inspired Silica-Coated Gold Nanorods as a Photothermal Therapeutic Platform for Treating Brain Tumors. Advanced Materials. 2017;:1605563.