“This was a short-term experiment, just eight weeks,” Liu said. “In people, obesity doesn’t occur overnight or even in eight weeks. People have a suboptimal lifestyle for 20, 30 years before they become obese. It’s possible that if you have Western diet for so long, you cross a point of no return and your Paneth cells don’t recover even if you change your diet. We’d need to do more research before we can say whether this process is reversible in people.”

Eating a Western diet impairs the immune system in the gut in ways that could increase risk of infection and inflammatory bowel disease, according to a study from researchers at Washington University School of Medicine in St. Louis and Cleveland Clinic.

The study, in mice and people, showed that a diet high in sugar and fat causes damage to Paneth cells, immune cells in the gut that help keep inflammation in check. When Paneth cells aren’t functioning properly, the gut immune system is excessively prone to inflammation, putting people at risk of inflammatory bowel disease and undermining effective control of disease-causing microbes. The findings, published today (May 18, 2021) in Cell Host & Microbe, open up new approaches to regulating gut immunity by restoring normal Paneth cell function.

“Inflammatory bowel disease has historically been a problem primarily in Western countries such as the U.S., but it’s becoming more common globally as more and more people adopt Western lifestyles,” said lead author Ta-Chiang Liu, MD, PhD, an associate professor of pathology & immunology at Washington University. “Our research showed that long-term consumption of a Western-style diet high in fat and sugar impairs the function of immune cells in the gut in ways that could promote inflammatory bowel disease or increase the risk of intestinal infections.”

Giving COVID survivors just one dose of the vaccine could help end the pandemic faster In South Korea, an analysis that included more than 500000 people age 60 and older found that the Pfizer vaccine was 89% effective in preventing infection just two weeks after the first shot. AstraZeneca’s vaccine, which has not been authorized for emergency use in the U.S., was found to be 86% effective in that same time period. Again, that’s after a single dose, and it’s regardless of prior COVID history.

Commentary: Getting a second dose of Pfizer or Moderna’s coronavirus vaccine might not be necessary for COVID survivors.

A literature search revealed that one of the Siglec molecules had been previously linked to the autoimmune disease lupus. Finding connections between these different kinds of molecules starts to fill in a new and emerging picture of biology, Bertozzi says. That picture may look something like this: RNA hangs out on the cell surface, decorated with sugars. These sugars stick to Siglec proteins that help the immune system distinguish friend from foe.

In a surprise find, scientists have discovered sugar-coated RNA molecules decorating the surface of cells.

These so-called ‘glycoRNAs’ poke out from mammalian cells’ outer membrane, where they can interact with other molecules. This discovery, reported May 17, 2021, in the journal Cell, upends the current understanding of how the cell handles RNAs and glycans.

“This was probably the biggest scientific shock of my life,” says study author Carolyn Bertozzi, a Howard Hughes Medical Institute Investigator at Stanford University. “Based on the framework by which we understand cell biology, there’s no place where glycan sugars and RNA would physically touch each other.”

CAR natural killer T cells that co-express GD2 and interleukin-15 were found to be safe and to demonstrate evidence of in vivo expansion and localization to metastatic sites in patients with stage IV relapsed/refractory neuroblastoma.