Do misfolded prions always eventually result in disease once entering the bloodstream, barring premature death, etc?

r/

Do I understand this properly from reading posts here? That it’s not enough for a prion to enter – but your body needs to make copies of it?

So, is that an inevitability with a prion(lets say, one from CJD) and is it eternally indestructible inside of your body, blood, eye, (wherever you contacted it) so long as you live long enough for your body to accidentally make copies of the misfolded prion?

And then you’re doomed.

Or is there a chance your body can get rid of it in your blood some other way somehow before making copies? I’m guessing not because your body doesn’t even know somethings wrong with it or that it’s foreign, right?

Thanks

Comments

  1. JackError1337 Avatar

    Exposure to prions over a certain amount will almost always lead to eventual development of the disease and then death within a year of symptoms starting.

    You body doesn’t make copies of prions like how a virus works but they actually force/trigger existing proteins to change shape and fold into prions.

    Anything less than that exposure amount I believe is just a lower chance of it coming into contact with a susceptible protein for long enough to cause proliferation of incorrectly folded proteins. So with a low enough number of them in the body I don’t see why they couldn’t get removed (somehow, unsure exactly how) because causing the long-term illnesses.

  2. EtherealPheonix Avatar

    For clarity, all prions are by definition misfolded otherwise they are just Proteins, also prions don’t get “copied by your body,” they do the copying themselves by causing other proteins of the same original type to misfold in the same way they did, which causes a chain reaction, it’s not relying on your body to do anything other than have the correct type of protein exist.

    As for your question yes it’s technically possible, the protein has to encounter the correct protein at the correct energy and orientation for the misfolding reaction to occur in order to replicate. This has a probability of happening (I have no idea what the numbers are or where to find them) that would vary by specific protein but certainly isn’t guaranteed. Nothing in your body persists forever though prions are on the more persistent side, your body won’t be actively getting rid of them and has no known immune response so you will need to rely on it getting caught in the various natural processes that get rid of other things in your body which if like in your scenario it’s in your bloodstream could actually be fairly quick.

    Unfortunately even if you get lucky on one prion like most molecules, especially self replicating ones they rarely occur alone so if you managed to get one inside of you you likely got enough that the chance of cascading replication is almost guaranteed so it instead becomes a question of whether they are able to replicate fast enough to cause significant problems before something else kills you.

  3. atomfullerene Avatar

    Prions are just one specific protein, prp. Proteins misfold constantly and are normally cleaned up by garbage collection in our cells. Other proteins dont usually misfold other proteins either.

  4. iKeyvier Avatar

    PrP (the protein that can misfold and turn into a prion) is expressed in most tissues in our bodies. The reason why we only see prions accumulate in our brain is that the rest of the body is subject to turnover, while the nervous system essentially isn’t; and these sort of diseases necessitate of years, if not decades, of prion accumulation to show symptoms.

  5. azssf Avatar

    What exactly causes Prp to ‘misfold’ initially? What reaction is required for a prion to get Prp to move from its correct folding pattern to a ‘misfolded’ one once it ‘infects’ another body?

    ( quoted used bc uncertain of correct terminology)