Phages and Autoimmune Diseases

Last month I wrote about bacteriophages (phages, for short) and Parkinson’s Disease.  If you remember, a phage is a virus that kills bacteria.  Those researchers found an abnormally high number of phages had killed off good Lactobaccillus in PD patients: ““The depletion of Lactococcus due to high numbers of strictly lytic phages in PD patients might be associated with PD development.”[i]  The implication:  what amounts to a viral infection is at the root of the bacterial alterations found in those affected with PD.

Then last week, an article was published that provided more substantiation for the theory that actually, ultimately, Parkinson’s is an autoimmune disease.  German researchers showed that a certain kind of T-cell (immune cell) attacked dopamine cells from those with PD but not those from healthy individuals.[ii]

Taking all the different puzzle pieces of recent findings and trying to put them together as best as I can into a cohesive picture:  a viral infection, in the form of bacteriophages, causes an alteration of the bacterial microbiome in the gut.  This, in turn, evokes an immune response, including the release of large numbers of the immune protein alpha synuclein.  By some as yet unknown mechanism, this protein becomes distorted, begins to aggregate, and ultimately causes an (auto)immune reaction in the brain that leads to the destruction of the dopamine producing cells in the substantia nigra in the brain.

Yes, there are a lot of pieces missing, but that’s a lot of new findings in just the last year or two.  Progress is being made.  And, by the way, this finding – that PD looks more and more autoimmune – may actually lead to treatment sooner rather than later.  These German scientists “…also discovered that an antibody that was already in use in the hospital for the treatment of psoriasis was ‘able to largely prevent the death’ of the brain cells.  ‘The findings from our study offer a significant basis for new methods of treating Parkinson’s disease.’”

I’ve been thinking about all this since I read of the German findings last week, especially as I had dinner last Thursday with a friend with PD.  I’ve been in one of my major brood sessions!  So you can imagine how interesting I found it this morning to read that now bacteriophages are implicated in the autoimmune inflammatory bowel diseases as well.  Interestingly, these researchers suggest that inflammation alters the abundance of phages and thus, the gut environment.[iii]  But they are still unsure how this ties in together, ie. What comes first, the chicken (virus) or the egg (inflammation)? The researchers suggest though that perhaps, sometime in the future, phage therapy may be developed to manipulate the gut bacteria and reduce inflammation, eliminating disease.  More than that, phage testing may let doctors know that someone is predisposed to developing IBD…or Parkinsons…or, perhaps, many, many other autoimmune diseases.

Does it all come back to gut viruses? Stay tuned.

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[i] https://www.medicalnewstoday.com/articles/322114.php

[ii] https://www.medicalnewstoday.com/articles/322114.php

[iii] https://www.eurekalert.org/pub_releases/2018-07/uoca-rfc072318.php