Engineered Fibroblast Extracellular Vesicles Attenuate Pulmonary Inflammation and Fibrosis in Bleomycin-Induced Lung Injury.
Publication Year:
2021
PubMed ID:
34660588
Funding Grants:
Public Summary:
Pulmonary fibrosis is a lung disease that gets worse over time and currently has no cure. Scientists have created special tiny particles called ASTEX, made by engineered skin cells, which carry helpful molecules to repair tissues.
In lab tests, ASTEX helped reduce inflammation in immune cells and prevented lung cells from turning into scar-forming cells. When given to healthy mice, ASTEX was safe and didn’t cause harm. In mice with lung injury, ASTEX lowered inflammation, reduced lung damage, and improved survival.
This research suggests ASTEX could be a promising new treatment to reduce inflammation and scarring in lung diseases like pulmonary fibrosis.
Scientific Abstract:
Pulmonary fibrosis is a progressive disease for which no curative treatment exists. We have previously engineered dermal fibroblasts to produce extracellular vesicles with tissue reparative properties dubbed activated specialized tissue effector extracellular vesicles (ASTEX). Here, we investigate the therapeutic utility of ASTEX in vitro and in a mouse model of bleomycin-induced lung injury. RNA sequencing demonstrates that ASTEX are enriched in micro-RNAs (miRs) cargo compared with EVs from untransduced dermal fibroblast EVs (DF-EVs). Treating primary macrophages with ASTEX reduced interleukin (IL)6 expression and increased IL10 expression compared with DF-EV-exposed macrophages. Furthermore, exposure of human lung fibroblasts or vascular endothelial cells to ASTEX reduced expression of smooth muscle actin, a hallmark of myofibroblast differentiation (respectively). In vivo, intratracheal administration of ASTEX in naive healthy mice demonstrated a favorable safety profile with no changes in body weight, lung weight to body weight, fibrotic burden, or histological score 3 weeks postexposure. In an acute phase (short-term) bleomycin model of lung injury, ASTEX reduced lung weight to body weight, IL6 expression, and circulating monocytes. In a long-term setting, ASTEX improved survival and reduced fibrotic content in lung tissue. These results suggest potential immunomodulatory and antifibrotic properties of ASTEX in lung injury.