Computer Scientist Creates Kill-Switch for Biological Viruses • Hacker News Board

Re: Computer Scientist Creates Kill-Switch for Biological Viruses

#21

Post by delinka » Sat, Nov 05, 2011, 3:57 AM UTC

curt wrote: post #17

colanderman wrote: post #14

Earlier quoted context omitted.

Yes, I truly hope that these proteins do work as intended, but a part of me thinks "what about obscure virus X, which is capable of easily infecting most cells in a body but doesn't exhibit any negative effects on health?" If such a virus existed then these proteins, administered in significant enough amounts, would kill a person infected with virus X.

Nah you would be given a dosage large enough just to kill the invading virus. It could hurt the person, but killing them is unlikely. Actually wrote a paper on a something similar I came up with back in undergrad using HIV.

I don't follow that logic. Sure, it stands to reason that if the drug can only kill infected cells, and the human hasn't already lost enough cells to kill them, then the drug won't kill the human.

But let's suppose that you can't measure in advance the number of cells that are infected, nor can the drug actually tell the difference between infected and not-infected cells (due to the aforementioned genetic abnormality.) What happens when the drug kills too many normal cells? The human dies.

Re: Computer Scientist Creates Kill-Switch for Biological Viruses

#22

Post by curt » Sat, Nov 05, 2011, 5:46 PM UTC

delinka wrote: post #21

curt wrote: post #17

Earlier quoted context omitted.

Nah you would be given a dosage large enough just to kill the invading virus. It could hurt the person, but killing them is unlikely. Actually wrote a paper on a something similar I came up with back in undergrad using HIV.

I don't follow that logic. Sure, it stands to reason that if the drug can only kill infected cells, and the human hasn't already lost enough cells to kill them, then the drug won't kill the human. But let's suppose that you can't measure in advance the number of cells that are infected, nor can the drug actually tell the difference between infected and not-infected cells (due to the aforementioned genetic abnormality…

My point was that there are so many more healthy cells vs infected cells except on rare instances that even it kills healthy cells too they are far larger in number. Just like what happens during radiation treatments or any number of other treatments.

Still it would likely be a staged treatment that wouldn't kill the entirety of infected cells in a single dosage. The benefit is that you could see if there were adverse reacts before continuing.

Re: Computer Scientist Creates Kill-Switch for Biological Viruses

#23

Post by delinka » Sat, Nov 05, 2011, 11:59 PM UTC

curt wrote: post #22

delinka wrote: post #21

Earlier quoted context omitted.

I don't follow that logic. Sure, it stands to reason that if the drug can only kill infected cells, and the human hasn't already lost enough cells to kill them, then the drug won't kill the human. But let's suppose that you can't measure in advance the number of cells that are infected, nor can the drug actually tell the difference between infected and not-infected cells (due to the aforementioned genetic abnormality…

My point was that there are so many more healthy cells vs infected cells except on rare instances that even it kills healthy cells too they are far larger in number. Just like what happens during radiation treatments or any number of other treatments. Still it would likely be a staged treatment that wouldn't kill the entirety of infected cells in a single dosage. The benefit is that you could see if there were advers…

Now that I think about it, it's much more like chemotherapy. Which does cause terrible side effects by affecting the entire body and not just cancer cells.

Radiation is targeted and not administered 'generally' like a drug would be. If you could aim drugs, chemotherapy would likely change drastically.

Re: Computer Scientist Creates Kill-Switch for Biological Viruses

#24

Post by teyc » Sun, Nov 06, 2011, 7:58 AM UTC

Roboprog wrote: post #5

Something that is not explicitly stated in the article, other than "virus kills the host cells, anyway", is that the drug works by finding host cells containing viral (specific) RNA, and then killing the host cells (I assume apoptosis means rupturing lysosomes - digestive enzyme packets). The article mentions the two active "tags" and what they do, but not the context and effect: kill infected cells to stop further i…

Incidentally my sister just got a paper published in the New England Journal with a similar approach (kill switch) for use in gene therapy http://www.nejm.org/doi/full/10.1056/NEJMoa1106152

This could be pretty important work to make gene therapy much safer.

   A single dose of dimerizing drug, given
   to four patients in whom GVHD developed, 
   eliminated more than 90% of the modified
   T cells within 30 minutes after 
   administration and ended the GVHD
   without recurrence.