Your blood cells are not what they seemS

Bioengineers have figured out a new way to deliver cancer-killing drugs to your body. They hide the drugs inside the skins of red blood cells. Literally.

The technique worked so well that we have to ask: what else could a clever bioengineer hide inside our red blood cells, to circulate secretly around our bodies?

UC San Diego bioengineers Liangfang Zhang and Che-Ming Hu wanted a way to deliver nanoparticle medicines to patients without triggering an immune response that would eradicate the medicine before it could work. So they peeled the membranes off of red blood cells, and wrapped them around the nanoparticles. It worked, in tests on mice. They seem to have hit upon a promising way to disguise an invader in your body, because your immune system would never attack its own army of red blood cells.

According to a release about the study from the Proceedings of the National Academy of Sciences, where the results were published this week:

Using the body's own red blood cells marks a significant shift in focus and a major breakthrough in the field of personalized drug delivery research. Trying to mimic the most important properties of a red blood cell in a synthetic coating requires an in-depth biological understanding of how all the proteins and lipids function on the surface of a cell so that you know you are mimicking the right properties. Instead, Zhang's team is just taking the whole surface membrane from an actual red blood cell.

"We approached this problem from an engineering point of view and bypassed all of this fundamental biology," said Zhang. "If the red blood cell has such a feature and we know that it has something to do with the membrane — although we don't fully understand exactly what is going on at the protein level — we just take the whole membrane. You put the cloak on the nanoparticle, and the nanoparticle looks like a red blood cell."

Though Zhang clearly has only the best of intentions, his research left me wondering about nefarious applications of this same technique. Why not disguise nanoparticle poisons inside red blood cells, or — once we have much better nanotech — surveillance devices? Obviously this is stuff that's at least a decade or more away, but it's interesting to think about all the possibilities.

What is really circulating in your blood? We may be the last generation who can be absolutely certain that our blood cells are all exactly what they seem.

Read the full scientific article via PNAS

Image by Sebastian Kaulitzki/Shutterstock