Alejandro P. Heuck, PhD

American Lung Association Scholar: Diseases of Infants and Children

While people with cystic fibrosis live longer today than in years past, they still succumb to a deadly lung infection, Pseudomonas aeruginosa, because of its antibiotic resistance. By studying how P. aeruginosa works in the lung, Alejandro Heuck, PhD, hopes to develop a way to block the infection in people with CF.

"In cystic fibrosis, the lungs get infected by pathogens very early, and once they are established it's very difficult to eradicate them," Dr. Heuck says. "Ultimately, the pathogen damages the lung and the person with CF dies. We try to delay this as long as possible using antibiotics, but the pathogen rapidly learns how to resist the treatment. We need to find alternative ways to attack the pathogen."

With assistance from an American Lung Association Biomedical Research Grant, Dr. Heuck is studying the way in which P. aeruginosa injects toxins directly into a target cell using a "bacterial machine" resembling a syringe. During toxin injection, this machine pokes a hole in the target cell, allowing the passage of different bacterial toxins. Dr. Heuck is trying to isolate the proteins that poke the holes and see how they work. "Knowing how the protein works to create the hole could allow us to find a way to plug it up and interfere with the bacterial infection," he says.

So far, he has isolated the proteins involved in the bacterial machine, and identified the segments of the proteins that interact with the membrane of the target cell. The next step is to combine these proteins to see how they work together to engage with the bacterial syringe. This research should provide information on potential targets for new drug therapy that would block P. aeruginosa toxin injection in the lung cells of people with CF.

"This was a completely new, and very challenging, research project," Dr. Heuck says. "In a difficult funding situation, the American Lung Association gave me a chance to train people and collect preliminary data that will now allow me to apply for federal funding to continue the project."