RNA-based inhaler prevents the severe course of pneumonia
The drug targets overactive white blood cells that cause lung damage during severe infection. The study is published in the journal Nature Communications.Researchers from the Technical University of Munich have developed an RNA-based treatment that targets overactive macrophages in the lungs, preventing severe inflammation and scarring of lung tissue. If the clinical trial is successful, the inhaler will be used to treat complications of coronavirus infection and pneumonia.
The key active component of the drug RCS-21 inhibits the activity of the microRNA-21 (miR-21) molecule, a trigger for the production of overactive macrophages in severe lung infections. MicroRNAs are a class of small regulatory RNAs that have been shown to regulate multiple cellular functions and play an important role in the regulation of gene expression.
One type of white blood cell, macrophages, play a critical role in initiating, maintaining, and eliminating inflammation in the body. When lung cells are destroyed by infection or inhalation of toxic substances, lung macrophages trigger a massive immune response that itself causes further damage.
The researchers used a feature of macrophages to deliver a drug to the lung cells. These white blood cells possess sugar receptors that identify bacteria and fungi by complex sugar molecules on the surface of the invader. The researchers combined RCS-21 with trimannose and prepared the drug in spray form.
In a series of experiments, the drug was given to mice with drug-induced lung injury using an inhaler. The analysis showed that the use of trimannose ensures drug delivery to the intended target. The activity of miR-21 was reduced by more than half. In addition, the mice showed a significant reduction in lung inflammation and fibrosis compared to control group mice.
A similar result was obtained when the drug was injected into human lung tissue. Currently, scientists are working on improving the safety of the drug. The first human clinical trials are scheduled for 2024.