Skin might have an immune system of its own

Hello Nature readers,
Today we learn that our skin might have an immune system of its own, delve into the neutrino fog and follow one man’s long walk along the path of humanity’s greatest migration.

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Skin has its own immune system

The skin seems to be able to produce its own antibodies to keep microbes in check. “When the immune system sees a friendly bacterium, you would think that it would just give a friendly wave and walk in the other direction, but that’s not at all what happens,” says microbiologist and study co-author Michael Fischbach. In mice colonized by Staphylococcus epidermidis, a common and harmless bacterium found on human skin, the skin was able to generate antibodies even when other parts of the immune system were disabled. And this surprise power might be harnessed to fight pathogens: when researchers modified S. epidermidis to display part of the tetanus toxin, the skin response protected mice from a lethal dose.

US and China sign narrower science pact

The United States and China have signed a five-year agreement that dictates how the nations will cooperate on science and technology research. It’s a new version of a pact forged in 1979 and normally renewed every five years — but which expired last year amid rising tensions. The new deal covers collaboration on basic science projects between departments of the two governments and excludes work on technologies that could be important to national security, such as artificial intelligence. Unlike the previous iteration, it doesn’t include any information on collaboration between universities or private companies.

Intermittent fasting slows luscious locks

Intermittent fasting, a weight-control regime that involves only eating at certain times, triggers a stress response that can slow hair growth. Shaved mice subjected to intermittent fasting regrew less hair in three months than those that ate a similar number of calories with no time restrictions. Researchers traced this effect to the death of hair-follicle stem cells. The regime seemed to have a similar effect on people: hair growth in around two-dozen human intermittent-fasters was 18% slower than in a control group.

‘Neutrino fog’ reveals and obscures

For the first time, physicists have observed glimmers of the ‘neutrino fog’, signals from particles called neutrinos that mimic those expected to be produced by dark matter — the mysterious substance thought to make up the bulk of matter in the Universe. That’s exciting for physicists because it means that detectors have become sensitive enough to pick up signals of dark matter. But there’s a catch: the neutrino signals could obscure the dark-matter signals that scientists are so eager to observe.

Encouragement from Kim Stanley Robinson

Science-fiction writer Kim Stanley Robinson, who authored the classic Mars terraforming trilogy, offered a vision of how to keep Earth habitable in his influential 2020 climate-change novel, The Ministry for the Future. “People are hungry for the feeling that everything could work out OK if we do things right. The book serves as a kind of encouragement,” he says. “At the same time, the start of the novel is so awful that it reproduces the feeling of climate dread. Really, I don’t even like to look at those pages again.” His message to undergraduates is to turn climate dread into purpose. “Whatever you’re interested in, whatever your personal interests are, that can become climate work.”

CRISPR patents block India’s farmers

Early in his career, biotechnologist Anurag Chaurasia helped lead a project to develop genetically modified, pest-resistant Bt cotton. But the patent on the relevant Bt gene was held by the agrochemical company Monsanto (now owned by Bayer). “Ultimately, Indian farmers could not reap the benefits of state-subsidized seed varieties; those using Bt cotton now rely on expensive proprietary seeds,” writes Chaurasia. “Having witnessed one failed project, I urge scientists in low- and middle-income countries to pay more attention to who owns CRISPR–Cas9 patents and under what terms they are willing to license this innovation.”

Walking the greatest journey ever taken

Pulitzer-prizewinning journalist Paul Salopek is on the walk of a lifetime: covering the 38,000-kilometre route along which ancient humans are thought to have migrated from Africa, through Asia, all the way to the southern tip of South America. Salopek started in 2013 in Herto, Ethiopia; home to some of the oldest known fossils of modern humans. In his latest update, he is in Seoul, South Korea — around the same time that a political crisis came to a head with the declaration of martial law by president Yoon Suk Yeol.