Numerous technologies that use and help nanovesicles to deliver drugs to disease sites have been developed over the past few years, as any regular reader of Medgadget can attest to. We’re now at a stage when figuring out how to manufacture so-called extracellular nanovesicles (ENV) in millions, properly targeted, and on demand is a major hurdle to bring many nanotechnologies to clinical practice.
Ligands-grafted extracellular vesicles under transmission electron microscope, scale bar is 200 nm. Image: Yuan Wan
A team of scientists working at Penn State University, Second Affiliated Hospital of Southeast University and Jiangsu Cancer Hospital & Jiangsu Institute of Cancer Research in Nanjing, China, have developed a way to coax the immune system cells to generate nanovesicles that can then be filled with different drug compounds.
An announcement about the research from Penn State explains the details:
To create targeted nanovesicles, ligands — perhaps short pieces of protein — need to be attached to the nanovesicle wall so they can recognize tumor cells. The process for making targeted nanovesicles now requires using viruses to insert relevant DNA fragments into the genome of the donor cells and then collecting ligand-bearing nanovesicles released from the gene-modified cells.
Yuan, working with Siyang Zheng, [Penn State] associated professor of biomedical engineering, developed a simpler and faster method for attaching ligands. The researchers chemically graft the lipid-tagged ligands onto the cell membrane. They do this before they pass the cells through a sieve, which converts the cell membranes into millions of vesicles bearing ligands that can be filled with an appropriate drug to target the cancer.
The researchers used mouse autologous immune cells and created the ligand-targeted, fillable nanovesicles in the laboratory. They then infused these drug-loaded nanovesicles into the original mouse to treat tumors.
“This approach enables us to create nanovesicles with different ligands targeting different types of tumors in about 30 minutes to meet actual needs,” said Zheng. “With this approach, we also can put different types of ligands on a nanovesicle. We could have one ligand that targets while another ligand says, ‘don’t eat me.'”
Cancer-targeted drug-loaded EVs can significantly inhibit tumor proliferation (Ki67 staining becomes weak after treatment). Image: Yuan Fang
Study in journal Cancer Research: Aptamer-Conjugated Extracellular Nanovesicles for Targeted Drug Delivery…
Via: Penn State…
Top image by: Xin Zou
