Targeting extracellular vesicle delivery to the lungs by microgel encapsulation.

Extracellular vesicles (EVs) secreted by stem and progenitor cells have significant potential as cell-free 'cellular' therapeutics. Yet, small EVs (<200 nm) are rapidly cleared after systemic administration, mainly by the liver, presenting challenges targeting EVs to a specific organ or tissue. Microencapsulation using natural nano-porous hydrogels (microgels) has been shown to enhance engraftment and increase the survival of transplanted cells.

Electron Leak From the Mitochondrial Electron Transport Chain Complex I at Site I Is Crucial for Oxygen Sensing in Rabbit and Human Ductus Arteriosus.

Background As partial pressure of oxygen (pO) rises with the first breath, the ductus arteriosus (DA) constricts, diverting blood flow to the pulmonary circulation. The DA's O sensor resides within smooth muscle cells. The DA smooth muscle cells' mitochondrial electron transport chain (ETC) produces reactive oxygen species (ROS) in proportion to oxygen tension, causing vasoconstriction by regulating redox-sensitive ion channels and enzymes.