Stories about: Jonathan Kagan

How do cells release IL-1? The answer packs a punch, and could enable better vaccines

In hyperactivated immune cells, gasdermin D punches holes in the cell membrane that let IL-1 out — without killing the cell.

Interleukin-1 (IL-1), first described in 1984, is the original, highly potent member of the large family of cellular signaling molecules called cytokines that regulate immune responses and inflammation. It’s a key part of our immune response to infections, and also plays a role in autoimmune and inflammatory diseases. Several widely used anti-inflammatory drugs, such as anakinra, block IL-1 to treat rheumatoid arthritis, systemic inflammatory diseases, gout and atherosclerosis. IL-1 is also a target of interest in Alzheimer’s disease.

Yet until now, no one knew how IL-1 gets released by our immune cells.

“Most proteins have a secretion signal that causes them to leave the cell,” says Jonathan Kagan, PhD, an immunology researcher in Boston Children’s Hospital’s Division of Gastroenterology. “IL-1 doesn’t have that signal. Many people have championed the idea that IL-1 is passively released from dead cells: you just die and dump everything outside.”

Read Full Story | Leave a Comment

When asymptomatic viral infections turn deadly: Lessons from flies

Fruit flies

When Dr. Jonathan Kagan’s student came to him complaining of dying fruit flies, the two were unaware that their research was about to take an unexpected turn. Their goal in establishing Drosophila lines had been to study virus-host interactions. It was quickly subverted when the flies died on exposure to carbon dioxide, used when transferring flies between vials.

This was surprising on two fronts. First, carbon dioxide is routinely used to anesthetize the flies, with no ill effects. Second, the uninfected flies did not die. The virus used to infect the flies, called vesicular stomatitis virus (VSV), normally does not cause symptoms, even with the virus making several thousand copies of itself.

Read Full Story | Leave a Comment

Can we supercharge vaccines? Added compound boosts T-cell production

supercharged vaccines oxPAPCBridging our innate and adaptive immune systems, dendritic cells are sentinels that circulate in the body searching out microbes and activating T-cells to destroy the invaders. They do this by presenting bits of the microbes on their surface—explaining why they’re often called antigen-presenting cells.

Reporting in Science this week, researchers describe a way to push dendritic cells into a “hyperactive” state, supercharging their ability to rally T-cells.

The key player, a fatty chemical called oxPAPC, is naturally found in damaged tissues and atherosclerotic plaques. It selectively targets dendritic cells and could, the researchers believe, enhance people’s immunity to a wide range of infections.

Read Full Story | Leave a Comment