Dr. Joel Finbloom: A new approach to the battle against lung infections in CF

Chronic bacterial infections are a relentless challenge for many people with cystic fibrosis (CF), including those on CFTR modulators, as bacterial infections are often resistant to even the strongest antibiotics and can cause lasting damage to the lungs. Dr. Joel Finbloom is on a mission to change that by developing a new way to deliver antibiotics that can outsmart the bacteria's defenses. 

To understand why this research matters, it helps to picture what's happening inside the lungs. 

Breaking down the castle walls 

The bacteria that cause lung infections in people with CF build protective structures called biofilms. These biofilms act like a castle, with walls made of sugars, proteins, and DNA that shield the bacteria from attack. 

We can think of antibiotics as soldiers trying to storm the castle and defeat the bacteria inside. But the biofilm fortress keeps them out, leaving the bacteria largely untouched. 

Dr. Finbloom is developing a new way to deliver these antibiotics alongside biofilm-degrading enzymes, which can be thought of as a demolition crew. These enzymes are already known and used in CF care but getting them to the site of infection can be challenging. The enzymes don't fight the bacteria directly. Instead, they break down the fortress walls, exposing the bacteria and leaving them vulnerable to attack from the antibiotics. Because the fortress walls are built from different materials, the demolition crew needs multiple tools to break each one down. 

“So essentially, we're breaking up the defence mechanism that bacteria use to evade antibiotics,” says Dr. Finbloom.   

Tiny delivery trucks 

Another challenge is the treacherous path to the castle. The castle housing the infectious bacteria sits deep in the lungs, and to reach it, the antibiotics and enzymes must travel through narrow, branching airways coated with a sticky substance called mucus that can trap them along the way. 

To evade the mucus and make it safely to the destination, Dr. Finbloom has created a nanoparticle, an incredibly tiny delivery truck about one one-thousandth the width of a human hair. Its small size allows it to navigate the lungs' narrow passageways. By putting the antibiotic soldiers and enzyme demolition crew together in the same truck, Dr. Finbloom can ensure they arrive at the same location at the same time. 

"We can hide it within our nanoparticle systems, kind of like a delivery truck," he says. "We're loading drugs into this delivery truck, we're protecting them until they reach their destination, and then we're unloading them only where they want to go." 

The truck has sensors that detect changes in the environment, signaling when it has reached the right place and triggering it to open and release its cargo. Crucially, the nanoparticle must stay sealed until it reaches the biofilm. As Dr. Finbloom puts it, "We don't have a delivery truck that's leaking cargo as it's driving down the freeway." 

Inside the lab 

Dr. Finbloom is an assistant professor of pharmaceutical sciences at the University of British Columbia. With a PhD in chemistry and a postdoctoral fellowship in bioengineering, he brings material science expertise to problems that have stumped scientists for years.  Supported financially through a Cystic Fibrosis Canada Early Career Investigator Award, Dr. Finbloom has built a lab at UBC focused on some of the toughest questions in cystic fibrosis infection research. His work was also recognized with the Marsha Morton Early Career Investigator Award and the Cathleen Morrison Research Impact Award, presented to the highest-ranked grant as evaluated by community reviewers. 

His goal is not to create a new antibiotic, but to make existing antibiotics work better against the stubborn biofilm infections that take hold in CF lungs. 

To do this, Dr. Finbloom and his students are building realistic versions of these bacterial biofilm fortresses and testing which combinations of enzymes and antibiotics their nanoparticles can deliver most effectively. 

Flexibility by design 

Dr. Finbloom wants his delivery system to be flexible, capable of carrying a variety of different antibiotics and treatments rather than being tied to just one. "I think there are probably a lot of approaches that could be successful, and I think ours is a complementary one," he says. "It's a complementary approach to a lot of other research that's going on out there." 

His nanoparticle platform is designed to work with the antibiotics already in use today and to carry whatever new therapies emerge in the years ahead. That gives researchers and clinicians another tool to take on one of the most stubborn problems in CF care.