gene therapy alternative?

[wheels]

While gene therapy is very promising, not being able to ‘undo’ the procedure should there be complications has always been a little worrisome to me.

I have been wondering if it might be possible to use a parasite (such as Trichinella…the parasite that causes trichinosis) and genetically modify it so that it would generate a desired protein. The parasite could then be removed or killed if there were complications with the treatment. I am using Trichinella as an example because it is a parasite with a fairly long lifespan, and while being a nasty one, appears to only replicate upon ingestion (so an injected one should not run into that situation).

Certainly an appropriate parasite would need to be chosen based on the tissue it inhabited and the tissue you were targeting, plus you would need to take steps to prevent the parasites from reproducing. I would like to know if this would be a reasonable approach towards generating proteins, etc. in a method that would be more reversible than gene therapy.

[MrMistery]

Maybe, but really hard to do: and think that you will have to make it so that the proteins are recognised as body proteins and not antigenes. I would use a bacteria instead

[mith]

It would be much riskier IMO, the parasite/bacteria would have to be immune from the human's defenses and what if complications arose? There wouldn't be anything to limit their growth..

[wheels]

"It would be much riskier IMO, the parasite/bacteria would have to be immune from the human's defenses "

Most parasites already have a mechanism for avoiding the body's immune defenses. The general idea would be to genetically modify the parasite to produce a desired protein, somewhat like what they have done by genetically modifying goats to express spider-silk protein in their milk. There are already methods for eliminating most parasites, so if there was a complication, you would destroy or remove the parasite. The goal would be to create a protein factory that could be left in place for a long period of time, and removed if there were any complications.

I can imagine a scenario where you could have a parasite to generated insulin for diabetics or factor-8 for people with hemophilia.

[MrMistery]

Hmm. since humuline comes from E.coli what you are saying is put E.coli cells inside the human body.. Not a good idea since it will divide and cause an infection as soon as you put it there.. So it seems this can not be done

[wheels]

"Hmm. since humuline comes from E.coli what you are saying is put E.coli cells inside the human body.."

I'm not saying that at all. I don't think bacteria would be a good method, I'm saying parasites only. I'm suggesting to genetically modify parasites so that they express a desired protein. If you insert a human gene into the parasite (using a vector or some other method), then the expressed protein should be identical to that of the human wildtype protein.

[mith]

Most parasites will drain the host, not to mention the possiblity of spreading, swelling, weight loss and other complications. Engineering a gene is easy compared to controlling gene expression(for example how much hormone to produce) and the parasite's behavior.