Clinician-scientists studied samples taken from the airway and blood of patients, and they discovered notable differences in children who experienced severe cases of RSV. One significant finding was the increased presence of natural killer (NK) cells in the airways of these children. This research aims to unravel the reasons behind the severity of the disease, potentially paving the way for identifying new treatment avenues in the future.
Respiratory syncytial virus (RSV) is the primary cause of hospital admissions for respiratory issues like bronchiolitis and pneumonia in young children. However, it remains unclear why some children only experience mild symptoms while others become severely ill. To delve into this mystery, clinician-scientists from Brigham and Women’s Hospital, part of the Mass General Brigham healthcare system, alongside Boston Children’s Hospital examined samples from patients’ airways and blood. They found distinct differences in children with severe RSV, particularly an increase in the number of natural killer (NK) cells in their airways. This descriptive study aims to deepen the understanding of severe illness and may facilitate the discovery of new targets for future therapies. The findings are published in Science Translational Medicine.
“As a physician, I take care of children with the most severe symptoms, and as a researcher, I am motivated to uncover why they become so ill,” stated corresponding author Melody G. Duvall, MD, PhD, from the Division of Pulmonary and Critical Care Medicine at Brigham and Women’s Hospital (BWH) and the Division of Critical Care Medicine at Boston Children’s Hospital. “NK cells play a crucial role as first responders during viral infections, but they can also lead to lung inflammation. Interestingly, our findings align with data from some COVID-19 studies, indicating that patients with more severe symptoms also show elevated NK cell levels in their airways. This connection suggests that further exploration of these cellular pathways is warranted.”
Duvall and her team, including lead author Roisin B. Reilly from the Division of Pulmonary and Critical Care Medicine at BWH, examined samples from 47 children with critical RSV infections, focusing on immune cells present in their airways and peripheral blood. They discovered that children suffering from severe illness had higher levels of NK cells in their airways and lower levels in their blood when compared to uninfected children. Moreover, they noticed changes in the cells’ characteristics and their ability to execute their immune function of eliminating diseased cells.
Duvall and her colleagues have previously reported a rise in pediatric RSV cases following the pandemic. Although healthcare providers can only offer supportive treatments for the severely affected children, vaccines to prevent RSV are now accessible for children aged 19 months and younger, adults over 60, and pregnant individuals.
