Will Nanosponges Soak Up the Toxins in Our Bodies?
By mimicking targeted cells rather than attacking toxins, nanosponges represent a single approach to combat a broad range of dangerous toxins in the bloodstream.Posted May 16, 2013
Imagine a future medical treatment which introduces microscopic bits of spongy material into your bloodstream which attach like Velcro to toxins and remove them safely through the liver.
Bioengineer Jack Hu and his team at the University of California San Diego have developed a promising approach to removing bacterial and venomous toxins which may lead to a single method which can combat a broad range of toxins in the body.
Dubbed a ‘nanosponge’, the minute polymer employs the tactic of biomimicry to latch on to toxins in the bloodstream. The ball-shaped polymer, 3000 times smaller than a red blood cell, is coated with proteins which are nearly identical to the membrane of red blood cells. Bacterial and venomous toxins, which are attracted to blood cell membranes, attach themselves instead to the decoy nanosponge, which can absorb and retain many toxin molecules.
The key mechanism which Hu’s team exploited is the pore-based surface structure of certain toxins which attach to the membranes of red blood cells, weakening the molecular bonds leading to the breakdown of the cell. Once the toxin attaches to the reciprocal pore structure of the membrane, the bond is stable, effectively neutering the toxin. Because the pore structure is ‘occupied’ in its attachment to the decoy, it poses no threat to cells in the liver as the toxin-laden nanosponges are eliminated from the body.
Toxins which employ the pore-based method of invading healthy cells are typically bacterial toxins, such as Methicillin-resistant Staphylococcus aureus (MRSA) and E. Coli, and venomous toxins from poisonous snakes and bee stings. Antibiotic treatments can be effective against bacterial infections, but new bacterial strains evolve with resistance to specific antibiotics. Because antibiotics and anti-venoms target the molecular structure of toxins, specific customized treatments are required for different diseases. The nanosponge, which mimics targeted cells rather than attacking toxins, represents a single approach to combat a broad range of dangerous toxins in the bloodstream.
The UCSD research team tested the nanosponge on mice given lethal doses of the toxin alpha-haemolysin, present in staphylococcus bacteria, MRSA. Of the mice “vaccinated” with the nanosponges, 89 percent survived. When given the nanosponges after being dosed with the toxin, 44 percent survived. Giving the mice nanosponges and alpha-haemolysin toxin at the same time, the mice remained healthy even when the ratio of toxin molecules to nanosponges was 70 to 1.
Nanosponges have only been tested on mice to date, and considerable testing is needed before human trials are underway. But the principle of nanosponges, attracting toxins to the red blood cell rather than targeting specific toxins, has heightened appeal because of its broad based method of combatting toxins.
Nanosponges are also a promising method of delivering drugs to specific targets within the body. Nanosponges loaded with an anticancer drug, for example, are three to five times more effective at reducing tumor growth than direct injection.
Although bacterial toxins are the focus of the UCSD nanosponge research, the method employed against pore-based toxins may lead to the use of biomimicry to remove chemical toxins from the body as well. With lax regulation of new chemicals in consumer products, our exposure is heightened to chemicals like BPA in can linings and hard plastics, flame retardants in couches, stain-resistant coatings on textiles and nonylphenols in detergents, shampoos and paints. Hazardous chemicals have become so ubiquitous that babies born today often have synthetic chemicals present in their blood.
As our modern lifestyles expose us to more environmental toxins, broad spectrum solutions like the nanosponge may be the most fruitful research to explore.