Human prion diseases are rare. So when, for the first time in fifty years, a new one is discovered, you’d think there would have been more media coverage.
The last time we had a new prion disease, Creutzfeldt–Jaekob disease, (CJD), it was associated with cannibalism and more recently mad cows. This one is connected to an orphan disease, Multiple system atrophy (MSA). It looks sometimes like Parkinsons and sometimes like something else.
Having Parkinsons is a poor enough diagnosis, but having MSA Parkinsons is worse. Rather than simply having your nerve cells fill with alpha-synuclein, MSA Parkinsons patients have the alpha-synuclein fill up their oligodendroglia, the cells that help sheath your nerves in protective myelin. So not only do you have Parkinsons symptoms, you have all the symptoms of an immune system that is shorting out, much like multiple sclerosis.
Currently, there are no treatments or cure, so this disease is managed by cobbling together treatments from other areas as supportive measures.
But researchers noticed a strange behavior in the plaques of MSA patients: ““toxic α-Syn aggregates exhibit prion-like behavior spreading from cell to cell.” This month they announced that, indeed, MSA was a prion based illness. Mice who were injected with Parkinsons plaques did not develop the disease, but mice who were injected with MSA plaques all got the illness. The researchers concluded: ” α-synuclein is the first new human prion to be identified, to our knowledge, since the discovery a half century ago that CJD was transmissible.”
Now we need to think about how many current patients with Parkinsons might have MSA. Differentiating the diagnosis takes a lot of testing, and many patients with symptoms may not have had that testing but simply been diagnosed with Parkinsons. One of the basic realities of prion diseases is that common sterilizing practices (autoclaving) are not effective at removing all infectious material.
At the same time, there may be a treatment for people who currently have MSA Parkinsons. Just last month a team of researchers found that polythiophenes (chemicals that make samples glow during experiments) bind preferentially to prions. Infected mice exhibited an 80% increase in survival. They were building on previous research by another group.
So, in the span of two months, we have a new terrible specter of a surgerical and blood passed infectious prion and a possible treatment for many currently affected individuals.