The complex is highly efficient: Since the heparin and growth factor are both active ingredients, and polycation is added only to bring it out of the water, as much growth factor as necessary can be delivered. "High loading efficiency is important because it allows us to reduce the frequency of injections," Wang adds.
The coacervate is not very viscous. This means that "you can use a needle as thin as a hair" to inject it, says Wang. "So if you inject that through tissue, the damage you create is very small." It could be done through a catheter, a long tube with a needle through it. This means the chest wouldn't have to be opened upa huge advantage over open-heart surgery.
HEALING A BROKEN HEART
During a heart attack, time is muscle. When a blocked blood vessel doesn't allow enough oxygen and nutrients to the heart, the muscle dies.
"After a heart attack, the muscle is dead, and what's replacing it is scar tissuea lot of collagen, but not many cardiac muscle cells. No muscle, no contraction," says Wang.
Once a heart attack has happened, the patient generally has two choices: Get a stent to open the blockage, or have surgery to bypass it. The heart tries to heal itself, but its self-remodeling efforts can have deleterious effects, like dilating ventricles until they're too big.
"If we can use growth factors to reverse that kind of adverse remodeling process, then we can probably rescue the heart function, which is the most important thing," notes Wang.
The growth factor complex would be injected at the appropriate timeright after the heart attack, or a few days laterto change how the heart repairs itself.
|Contact: Karen Hoffmann|
University of Pittsburgh