DNA nanorobots seek and destroy disease

Chemistry World ^ | 17 February 2012 | Jon Cartwright

[neverdem]

Researchers in the US have created a DNA-based nanorobot that can work its way through cell cultures, delivering cargo only at specific targets. The development could pave the way for programmable therapeutics, in which nanorobots would provide medical treatment only to certain types of cell or tissue. 

The DNA barrel only opens to release its cargo at specific cells

© AAAS

The field of nanomachines has taken off in recent years, mostly thanks to so-called DNA origami. In this technique, DNA strands can be folded controllably into a structure, onto which different molecules can be attached. Researchers have already shown that structures built using DNA origami can perform basic robotic tasks, such as sensing, computation and targeting cells. But, says biophysicist Shawn Douglas at Harvard Medical School in Boston, Massachusetts, no one has ever combined these tasks to do something more sophisticated, such as cell-targeted cargo delivery. 

Douglas, together with his colleagues, has now done this with a hexagonal, barrel-shaped DNA robot. The robot is just 35nm across and 45nm long, and is hinged at the base to clasp and unclasp in a clam-like manner. At the top, the barrel has 'locks' made of short DNA molecules that unlock when they bind with antigen 'keys', releasing the barrel's cargo, such as antibodies. 

In the researchers' experiment, billions of nanorobots were released into mixed cell cultures. The nanorobots diffused around, coming into contact with different types of cell. To cells without the appropriate surface key - that is, the right antigen combination - the nanorobots did nothing. However, when a nanorobot came across a cell with the correct antigen combination, its locks opened and the cargo was released - in some instances, killing the cell. 

'It is impressive, and I am amazed it worked so nicely and cleanly,' says Milan Stojanovic, who researches autonomous therapeutic devices at Columbia University in New York, US. 'It's surely an important contribution and crucial step in the right direction.' 

Ehud Shapiro, an expert in the crossover between computer science and molecular biology at the Weizmann Institute of Science in Israel, is also impressed. 'This pioneering and elegant work brings us closer to realising the vision of programmable drugs based on autonomous, programmable devices,' he says. 

Douglas says his group is seeing whether they can achieve similar results in mice but he thinks the nanorobots may not be restricted to programmable therapeutics. They could be used for 'diagnostic and even non-medical applications ... anywhere that electronic devices would be too large,' he says. 

References

S M Douglas et al, Science, 335, 831 (DOI: 10.1126/science.1214081)

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[neverdem]

A Logic-Gated Nanorobot for Targeted Transport of Molecular Payloads

Abstract
We describe an autonomous DNA nanorobot capable of transporting molecular payloads to cells, sensing cell surface inputs for conditional, triggered activation, and reconfiguring its structure for payload delivery. The device can be loaded with a variety of materials in a highly organized fashion and is controlled by an aptamer-encoded logic gate, enabling it to respond to a wide array of cues. We implemented several different logical AND gates and demonstrate their efficacy in selective regulation of nanorobot function. As a proof of principle, nanorobots loaded with combinations of antibody fragments were used in two different types of cell-signaling stimulation in tissue culture. Our prototype could inspire new designs with different selectivities and biologically active payloads for cell-targeting tasks.

[neverdem]

FReepmail me if you want on or off my combined microbiology/immunology ping list.

[neverdem]

Ping

[null and void]

Anyone needing affordable AFM scans, please FReep mail me.

[sten]

what could go wrong with this?

one strand of hair... some lab time... and they could assassinate any single target using a widely dispersed gas

(assuming it could be vaporized and operate once in the lungs, which it should)

[roadcat]

one strand of hair... some lab time... and they could assassinate any single target using a widely dispersed gas

I think that was on a recent Fringe sci-fi TV episode. Except at the last minute, the good guys switched the DNA to that of the bad guy, and the bad guy was the only one killed by dispersal of his gas.

[AnotherUnixGeek]

Researchers in the US have created a DNA-based nanorobot that can work its way through cell cultures, delivering cargo only at specific targets.

This is what medical care should look like in a few decades - an army of nanorobots in our bodies to supplement our immune systems, monitoring for and killing cancer cells before they can get established, treating inflammations in blood vessels to prevent blockages from ever getting started. Precise, pre-emptive, tailored to each person.

But we seem to be heading for a much different future, in which a government takeover of medical insurance will place far greater emphasis on rationing and reducing the cost of current medicines than on encouraging medical innovation.

[khelus]

[albionin]

My thoughts exactly. But the possibilities are astounding. I read a lot of science fiction in which nanites are keyed to an individual and swim through the blood removing anything that doesn’t belong to that person such as viruses and bacteria. Maybe that type of thing isn’t all that far fetched but it could also be used to kill people or maybe spread disease. A new targeted bio-weapon.

[sten]

oh yea, forgot that episode. last year i think.

and yes, given what was posted in this article, it would be possible.

this kind of stuff should be banned and any efforts to research it should be hunted down by all countries and stopped... with extreme prejudice

think about it. no world leader would ever be safe. anywhere. ever. they couldn’t travel to another country, that’s for certain. they couldn’t even be safe in their own country, as dna could be collected from hotel rooms or trashcans found outside their home.

and there is no reason whole groups of people couldn’t also be targeted. you could expose them all to a gas released on a plane and they would all die over a 6 month span to various diseases. the only common link would be that group. how they were killed would be almost impossible to detect once the disease has taken hold.

this is exceedingly bad.

[roadcat]

this is exceedingly bad.

I don't know if it could be banned; if so then the time to do it is now before the genie is out of the bottle. On a side-note, my wife is really into eating organic and that's pretty much what we eat. I thought it was just a fad until I started reading about all the genetically modified foods we have, and how there is a correspondence to diseases like autism, Alzheimers and others that have a low rate of occurrence in non-developed countries. You buy a cheeseburger and there is a 100 percent chance it is from cows eating genetically modified food; bad chemicals are in that beef. The guys in charge of the FDA approvals are Monsanto stooges, the company behind this stuff.

New science, if improperly unleashed can wreak havoc on us all.

[ShadowAce]

[SuziQ]

# 3 son used to talk about this! I’ll send this article to him!