Patients who become seriously ill or pass away from common respiratory viruses may have high levels of a crucial enzyme, according to a recent study led by Professor Katherine Kedzierska, a viral immunologist at the University of Melbourne’s Doherty Institute. This discovery sheds light on why some healthy individuals succumb to infectious diseases while others recover without complications.
The research team analyzed blood samples from patients hospitalized with severe seasonal influenza, Covid, or RSV, as well as samples from children with an inflammatory condition linked to Covid. They discovered that an enzyme called oleoyl-ACP-hydrolase (Olah) was significantly elevated in the sickest patients, including those who did not survive.
Olah plays a vital role in producing fatty acids, which are essential components of lipids. Lipids are crucial for cell membrane formation and energy storage in the body. Interestingly, individuals with low levels of Olah typically have milder disease symptoms, while those with elevated Olah levels are more likely to experience life-threatening complications.
Further investigations conducted by Dr. Brendon Chua, a viral and translational immunologist, in mice lacking the Olah enzyme showed less severe viral infections, reduced lung inflammation, and improved survival rates. The researchers hypothesize that Olah may be involved in activating macrophages, white blood cells responsible for combating pathogens. However, excessively high Olah levels could trigger an exaggerated immune response and harmful inflammation.
The study’s findings were published in the scientific journal Cell, garnering praise from experts like Prof. Peter Openshaw from Imperial College London. While the results are promising, additional research is necessary to determine Olah’s role in severe disease and its potential connection to other inflammatory conditions.
Professor Allen Cheng from Monash University acknowledged the study’s contribution to understanding severe infections but emphasized the need for further investigations. Questions remain about the significance of lipids and macrophages in determining disease severity, as well as possible interventions to improve patient outcomes.
Moving forward, Professor Kedzierska and her team aim to conduct larger studies to assess Olah as a predictive marker for severe symptoms, particularly in high-risk groups like pregnant women and individuals with comorbidities such as obesity. They are also developing Olah-based diagnostic tools to identify at-risk patients upon hospital admission.
By unraveling the role of Olah in infectious diseases, this research offers valuable insights into the factors influencing disease progression and severity. As the scientific community continues to explore these findings, the hope is to develop targeted interventions that can improve outcomes for patients battling severe viral infections.