Cell-Nanoparticle Hybrids, an Illustration of What is to Come
Work on nanoparticles and artificial cell structures for use in medicine is becoming more sophisticated. There is an emerging generation of simple but effective medical micro- and nanomachines, devices that will be manufactured in their millions and infused into the body to perform useful tasks, such as killing specific cells, or delivering specific signals to cells to cause them to regenerate more effectively, or clearing out unwanted metabolic byproducts that contribute to aging. A lot of interesting projects are presently underway, and this article is a good illustration of one branch of this work and its utility:
Nanoparticles could be used to neutralize toxins produced by many bacteria, including some that are antibiotic-resistant, and could counteract the toxicity of venom from a snake or scorpion attack. [The] "nanosponges" work by targeting so-called pore-forming toxins, which kill cells by poking holes in them. There are a range of existing therapies designed to target the molecular structure of pore-forming toxins and disable their cell-killing functions. But they must be customized for different diseases and conditions, and there are over 80 families of these harmful proteins, each with a different structure. Using the new nanosponge therapy [researchers] can neutralize every single one, regardless of their molecular structure.[Researchers] wrapped real red blood cell membranes around biocompatible polymeric nanoparticles. A single red blood cell supplies enough membrane material to produce over 3,000 nanosponges, each around 85 nanometers (a nanometer is a billionth of a meter) in diameter. Since red blood cells are a primary target of pore-forming toxins, the nanosponges act as decoys once in the bloodstream, absorbing the damaging proteins and neutralizing their toxicity. And because they are so small, the nanosponges will vastly outnumber the real red blood cells in the system. This means they have a much higher chance of interacting with and absorbing toxins, and thus can divert the toxins away from their natural targets.
In animal tests, the researchers showed that the new therapy greatly increased the survival rate of mice given a lethal dose of one of the most potent pore-forming toxins. Liver biopsies several days following the injection revealed no damage, indicating that the nanosponges, along with the sequestered toxins, were safely digested after accumulating in the liver.