University of California in San Diego (USA) developed imitating immune nanoparticle cells, which are targeted on inflamed lung tissues and are able to deliver medicines to where ordinary therapeutic agents cannot penetrate the necessary quantities. The effectiveness of the new method was proven on mice with inflamed light, and the nanoparticles on efficiency went around ordinary medicines. The results of the study are published in the journal Science Advances.
VLA-NP nanoparticles were designed from polymer nuclei coated with a cell membrane, which in large quantities contains a membrane protein VLA-4. This protein is expressed on the surface of the majority of immune leukocyte cells. Its special property is that it binds to VCAM-1 ligand located on the surface of endothelial cells. As a result of this interaction, the leukocytes “fill” damaged by inflammation of the tissue, which increases the fight against infection or other pathological process (for example, leukocytes can accumulate on the surface of malignant tumors).
The cell membrane with VLA-4 was obtained from genetically modified living cells, after which they were “put on” on polymer particles from lactic and glycolic acid. In diameter, the obtained nanoparticles reached 175 nanometers. During testing, scientists used a line of endothelial cells of the brain of bend.3 mice, which are known in the way that increase the expression of the VCAM-1 ligand in the presence of pro-inflammatory signals, for example, lipopolysaccharide, which is included in the bacterial membrane. It was confirmed that VLA-NP was aimed only on those cells that were subjected to an inflammatory process, and ignored the rest.
In the second stage of the study, scientists were placed inside the VLA-NP anti-inflammatory drug dexamethasone (DEX) and first experienced them on dendritic cells, the treatment of which lipopolisaccharide causes the release of cytokines. Reaffirming that the nanoparticles stopped the synthesis of inflammatory cytokines, the specialists moved to the mouse model of lung inflammation. Rodents introduced lipopolysaccharides directly into the lungs, and then intravenously nanoparticles with fluorescent tags. It turned out that VLA-NP was accumulated in the lungs, specifically binding to inflamed tissues. In terms of creatinine (renal toxicity marker), scientists have determined that the DEx nanoparticles inside did not have a toxic impact in contrast to the free dexamethasone, which was introduced by another group of animals.
As for the therapeutic effect, scientists did not find any signs of inflammation in the tissues of the lungs after opening mice. At the same time, free dexamethasone was never able to eliminate the pathological process, which emphasizes the benefits of the address delivery of the drug, and not its systematic impact on the body.