Barrel-like Nanobots Target Cancer Cells

Researchers at Harvard’s Wyss Institute have developed a nanobot that may allow for the detection and destruction of cancer cells. The nanobot will target and attach to cancerous cells, delivering a payload of antibodies that combat the disease’s spread.

The researchers, led by George Church, Ido Bachelet, and Shawn Douglas, utilized cutting-edge techniques to develop the nanobots, guide their attachment to cancer cells, and trigger the deployment of the antibodies.

According to Douglas, one of the researchers’ most significant achievements is the streamlined assembly and delivery process developed for the nanobot.

The efficiency of the process is due in large part to the barrel-like shape of the nanobot, which allows for many fewer opportunities for error than earlier box-shaped designs.

“If you make something with a lid that has to close and open again later, that’s another step—you have to assemble it open, or assemble it closed and then open it,” said Douglas.’

“And if you have to close it and open it again under different conditions, that’s a more complicated process to solve,” he added.

Though an open barrel may seem more likely to release its payload off-target, in-vitro trials with human cells have shown that the nanobots assemble correctly 97 percent of the time with no incidents of the payload deploying prematurely.

This concern is particularly important, since the consequences of the nanobots’ payload consistently reaching the wrong target could be deadly. In the case of cancer, where infected cells can be very similar to healthy cells, it becomes even more difficult to ensure that the nanobots’ deploy their payload correctly.

According to Naomi Genuth ’14, a student conducting related research, the authors were able to achieve such positive results by designing the nanobots to target proteins present on the surface of the cell rather than the DNA or RNA contained within.

“Previously,” said Genuth, “they were using DNA or RNA, which is not present on cell surfaces.”

To date, the nanobots have only been tested on human cells in-vitro.

But according to Douglas, rodent testing will soon be underway, paving the road for clinical trials further in the future.

The most immediate issue with the nanobots’ practicality as a treatment is the time it takes for them to locate and bind to their targets.

“We have to give them a few hours at least,” said Douglas.

Additionally, the harsh environment of the bloodstream may result in the destruction of nanobots before they can deploy their payload.

Nevertheless, the researchers are hopeful about the prospects of the nanobots.

“It’s groundbreaking—not only because it’s working with a very new field and very new technologies, but also because it is improving on these technologies and expanding the capabilities of what researchers in the future will be able to do with them,” said Genuth.

—Staff writer Aisha K. Down can be reached at aishadown@college.harvard.edu.