Shape of things to comeA first: plastic antibodies pass initial test

Published 14 June 2010

Plastic antibodies, which mimic the proteins produced by the body’s immune system, were found to work in the bloodstream of a living animal; the discovery is an advance toward medical use of plastic particles custom tailored to fight an array of antigens

Scientists have reported the first evidence that a plastic antibody, an artificial version of the proteins produced by the body’s immune system, works in the bloodstream of a living animal. The discovery, they suggest in a report in the Journal of the American Chemical Society, is an advance toward medical use of plastic particles custom tailored to fight an array of antigens.

Those antigens include everything from disease-causing viruses and bacteria to the proteins that cause allergic reactions.

In the report, University of California - Irvine’s Kenneth Shea, Yu Hosino, and colleagues refer to previous research in which they developed a method for making plastic nanoparticles that mimic natural antibodies in their ability to latch onto melittin, the main toxin in bee venom.

They made the antibody with molecular imprinting. The scientists mixed melittin with monomers and then started a chemical reaction that links those building blocks into long chains and makes them solidify. When the plastic dots hardened, the researchers leached the poison out, leaving the nanoparticles with tiny toxin-shaped craters.

The Engineer reports that their research, together with Naoto Oku’s group of the University Shizuoka in Japan, established that the plastic melittin antibodies worked like natural antibodies. The scientists gave laboratory mice lethal injections of melittin, which breaks open and kills cells.

Animals that then immediately received an injection of the melittin-targeting plastic antibody showed a significantly higher survival rate than those that did not receive the nanoparticles.

Such nanoparticles could be fabricated for a variety of targets, Shea said.

Journal of the American Chemical Society 132, no. 19 (26 April 2010): 6644–45 (DOI: 10.1021/ja102148f)