Sayak Banerjee. Amity University Kolkata
Scientists at Washington State University (WSU) discovered that other than immune cells, neutrophils also might play a major role in defense against infection, through a new drug delivery technology. Neutrophils are the most common type of white blood cells (WBCs) that lead the body’s immune system response. They established a technique in which the membrane of the neutrophils is uncased, emptying it using the nitrogen cavitation method, thus producing liposome-like nanovesicles from the human neutrophil membrane. These nanovesicles, about 100 to 200 nanometers wide, can then be loaded with medicine or drugs.
When the lung tissues are infected by Pseudomonas aeruginosa, which are implicated in hospital-acquired infections, the drugs to be delivered are an anti-inflammatory called resolvin-1 (RvD1) and an antibiotic called ceftazidime. As the nanovesicles are administered into a patient, they travel directly to the inflamed area, since they retain the characteristics of the WBCs, along with the medicines implanted to attack the infection. The nanovesicles possess cell adhesion proteins of their parent cells due to the intercellular interactions between the neutrophils and lung endothelium during lung infections which made this approach possible.
Most lung infections have two problems, the infection itself and inflammation created by a strong immune system response, due to which two types of drugs are used. RvD1 binds to G protein–coupled receptors, reducing the expression of adhesion molecules on endothelium, promoting the neutrophil apoptosis, and elevates the phagocytosis. At the same time, ceftazidime obstructs bacterial proliferation in the lungs. Scientists stated that if the patient is incorporated with two types of drugs, they will circulate the whole body instead of going directly to the lungs which eventually gives rise to a lot of toxicity. To prevent this, both the drugs can be loaded into the nanovesicles which particularly target the lung inflammation. It was seen that the nanovesicles filled with RvD1 decreased cytokine levels and neutrophil lung invasion, hence lowering the resolution time period of lung inflammation.
If the efficacy and safety of this method is finally proven, the nanovesicles can be loaded with any type of drug to treat various diseases as well as COVID-19. In spite of being a virus and not a bacterial pathogen, since COVID-19 cause inflammation in the lungs, anitiviral drug like remdesivir can be inserted into the nanovesicle, thus targeting that inflammation.
Also read: THE ORIGIN OF INSECT WINGS: DECIPHERING THE CENTURY OLD PUZZLE
Source: Gao, J., Wang, S., Dong, X. et al. Co-delivery of resolvin D1 and antibiotics with nanovesicles to lungs resolves inflammation and clears bacteria in mice. Commun Biol 3, 680 (2020). https://doi.org/10.1038/s42003-020-01410-5
3 thoughts on “Neutrophil-derived Nanovesicles: A Novel Drug Delivery System”