Armed with $1.2 million in funding from the National Heart, Lung and Blood Institute (NHLBI), researchers at Vanderbilt University Medical Center are searching to understand the cause of a rare airway disease in hopes of developing better treatments.
Idiopathic subglottic stenosis (iSGS) is an unexplained narrowing of the windpipe just below the vocal cords. The disease is progressive, slowly affecting the patient’s ability to breathe, and can be fatal due to airway obstruction if left untreated.
Affecting fewer than one in 200,000 people, the disease occurs almost exclusively in adult, Caucasian women, with most patients presenting in their 40s or 50s.
“In taking care of these patients, it has always struck me that they appeared so similar,” said Alexander Gelbard, MD, associate professor of Otolaryngology and co-director of the Vanderbilt Complex Airway Center (AeroVU). “The tightness of the demographics makes me believe there is a common thread driving this disease that we just don’t yet understand.”
Although treatments for iSGS exist, they’re invasive, costly for the patient and don’t always prevent the condition from recurring.
The new five-year study will dive deeper into the immune system’s response at the site of the fibrosis, or scarring, that takes place in the area below the patients’ vocal cords to answer questions about the source of the disease, what makes it better or worse and why it often recurs following surgical treatment.
The research team, led by Gelbard, hopes to determine whether the disease is related to an active infection or if bacteria triggers a self-reactive immune response. To do this, they’ll use cutting-edge single-cell sequencing techniques in partnership with Simon Mallal, MBBS, at VANTAGE (Vanderbilt Technologies for Advanced Genomics) to study tens of thousands of cells within each patient, looking at which cells are activated, what inflammatory pathways are disrupted within the scarred airway and which cells could be potential targets for treatment.
The team will also work with Suman Das, PhD, associate professor of Medicine in VUMC’s Division of Infectious Diseases, to study how bacteria influence the observed immune response in the scarred airway.
“We believe harnessing VUMC’s institutional infrastructure and collaborative culture will provide new insights into an old problem. Both technology and multidisciplinary perspectives have been essential ingredients in our prior success in studies of iSGS,” said Gelbard.
“Now, we are marrying the scientific capability and innovation of VANTAGE with expertise in pathogen detection and an advanced clinical program in airway disease to drive human health forward. We’re all excited about this project’s potential to directly impact the human condition.”
Previous studies of iSGS at Vanderbilt have uncovered inflammatory circuits inside patients with the condition that become activated and have revealed that bacteria may contribute to inflammation.
Another study, funded by the Patient-Centered Outcomes Research Institute (PCORI), looked at iSGS in a cohort of 1,000 patients from around the world to study the disease’s natural history and treatment outcomes.
Through his work, Gelbard hopes to show both iSGS patients and individuals afflicted with other rare diseases that uniting patients, physicians and scientific experts with a deep commitment to finding a cure can accelerate disease insights and meaningfully impact patients’ lives.
“Dr. Gelbard works at the micro level studying the disease processes, yet also at the global, macro level having created an international consortium of collaborators,” said Roland Eavey, MD, Guy M. Maness Professor and chair of Otolaryngology and director of the Vanderbilt Bill Wilkerson Center. “His research efforts also have translated to bedside management with enhanced surveillance and care for intubated and tracheotomized patients.”
This work is supported by NHLBI grant HL146401.
