In a new study from Harvard T.H. Chan School of Public Health, researchers found that a type of extracellular vesicle (EV) known as ARMMs also carries receptors that allow signaling without direct contact between cells. This capability may allow ARMMs to be engineered to deliver therapeutics directly to affected areas of the body, according to the study published online today in Nature Communications.
Senior author of the paper, Quan Lu, associate professor of environmental genetics and pathophysiology, previously described the body's mechanism for producing ARMMs. Unlike other EVs, which are generated within cells, ARMMs are secreted directly from the plasma membrane at the cell's surface. Although the physiological function of ARMMs remains unknown, the way that they are made may make them uniquely suited to carry certain molecules.
In the current study, the researchers found that ARMMs contain molecules used for Notch signaling, a type of intercellular communication that normally requires cell-to-cell contact. Notch receptors are plasma membrane proteins involved in critical physiological roles such as embryonic development, tissue homeostasis, and stem cell function. According to the new findings, ARMMs are able to facilitate Notch receptor signaling at a distance.
"Our research on ARMMs has tremendous potential for therapeutics and public health," Lu said. While other researchers have explored using EVs to deliver therapeutics, directing them within the body has been an obstacle. Lu believes that ARMMs provide a way past that barrier, and he was recently awarded a patent for generating, isolating, and engineering ARMMs. "It will likely be at least 10 years before we see these methods used in a clinical setting," Lu added. "But the path forward is clear."