Scientists are reporting the first evidence that a plastic antibody - an artificial
version of the proteins produced by the body's immune system to recognize and
fight infections and foreign substances - works in the bloodstream of a living
Plastic antibodies, such as this cluster of particles viewed under a powerful microscope, may fight a wide range of human diseases, including viral infections and allergies. Credit: Kenneth Shea
The discovery, they suggest in a report in the Journal
of the American Chemical Society, is an advance toward medical use of simple
plastic particles custom tailored to fight an array of troublesome "antigens."
Those antigens include everything from disease-causing viruses and bacteria
to the troublesome proteins that cause allergic reactions to plant pollen, house
dust, certain foods, poison ivy, bee stings and other substances.
In the report, Kenneth Shea, Yu Hosino, and colleagues refer to previous research
in which they developed a method for making plastic nanoparticles, barely 1/50,000th
the width of a human hair, that mimic natural antibodies in their ability to
latch onto an antigen. That antigen was melittin, the main toxin in bee venom.
They make the antibody with molecular imprinting, a process similar to leaving
a footprint in wet concrete. The scientists mixed melittin with small molecules
called 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. That left the nanoparticles with tiny
Their new research, together with Naoto Oku's group of the University Shizuoka
Japan, established that the plastic melittin antibodies worked like natural
antibodies. The scientists gave lab 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 says. "This opens the door
to serious consideration for these nanoparticles in all applications where antibodies
are used," he adds.
ARTICLE FOR IMMEDIATE RELEASE
"Recognition, Neutralization, and Clearance of Target Peptides in the Bloodstream
of Living Mice by Molecularly Imprinted Polymer Nanoparticles: A Plastic Antibody"
DOWNLOAD FULL TEXT ARTICLE
Posted June 9th, 2010