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Another trick up the immune system's sleeve

Roughly 8.5 million people in the United States suffer from peripheral artery disease (PAD), a narrowing of the arteries in the legs or arms (frequently due to the buildup of fatty plaque) that can cut off blood flow to the limbs, causing tissue death, gangrene and even amputation. Strategies to combat PAD by delivering compounds that promote angiogenesis (the growth of new blood vessels) to bypass the blocked arteries have been investigated but largely failed to improve outcomes. More recently, there has been increasing interest in using the body's immune system to treat ischemia as some immune cells are known to secrete blood-vessel-promoting compounds. However, getting therapeutic immune cells to concentrate and secrete a sufficient amount of the desired compounds where new vessels are needed remains a challenge. A new approach takes advantage of the surprising combination of implantable biomaterial scaffolds and childhood vaccines to solve this problem. In models of mice with hindlimb ischemia (a severe form of PAD), their technique increased the concentration of T cells at the ischemic site and stimulated angiogenesis, blood flow and muscle fiber regeneration for up to two weeks. Shown here: A scanning electron microscopy image shows an antigen-releasing scaffold that can recruit antigen-specific T-cells to sites of ischemic injury.

Visit Website | Image credit: Wyss Institute at Harvard University