A toxin derived from the substance bees insert into their victims when they sting is the agent that will destroy the sperm and HIV. The toxin, called melittin, comprises more than half of the dry weight of the venom of the honeybee Apis mellifera.
The nanoparticles will carry a synthetic version of the toxin melittin to the targets.
"Cells readily take in melittin," Wickline says. "But once it gets in, it pokes holes in cell membranes destroy the cells."
A local biotech startup company, Kereos Inc., is testing melittin as an anti-cancer agent.
Since melittin can annihilate almost any cell, the trick is to target the melittin to the specific cells intended for destruction (cancer, sperm, HIV) without causing collateral damage to other cells in the body.
Wickline and colleague Paul Schlesinger, MD, PhD, associate professor of cell biology and physiology, attacked that problem two years ago when they developed "nanobees," the name coined for nanoparticles that sequester melittin so that it neither harms healthy tissue nor is degraded before it reaches the intended target.
Wickline and his colleagues have also developed the ability to add agents to the nanobees to cause them to home in on specific target cells. Although nanoparticles are a few thousand times smaller than the dot above an "i," each can carry hundreds of thousands of molecules on its surface.
"We have the ability to attach and swap in various specific targeting molecules to nanoparticles that will bind with receptors on the surface of selected cells," Wickline says. "This gives the particles the ability to home in on specific target cells."
To get the nanobees to hook up with sperm and offload their lethal cargo, Wickline intends to target a well-known "docking site" on th
|Contact: Joni Westerhouse|
Washington University in St. Louis