Science Magazine – May 5, 2023 issue: The immune system protects us from cancer and infection using a powerful armamentarium that is kept in check by an array of regulatory processes. When they fail, the immune system can start attacking the host in a process known as autoimmunity. This special issue highlights recent advances in our understanding of autoimmune diseases and the regulation of immune tolerance. See the special section beginning on page 468.

When a delicate balancing act goes wrong

Antibodies that target self-antigens are an important component of certain autoimmune diseases and are sometimes used as a clinical marker for these syndromes. ILLUSTRATION: STEPHAN SCHMITZ/FOLIOART

A cardinal feature of the immune system is its ability to distinguish self from nonself. Although many early immunologists thought that its powerful defenses could rarely, if ever, be turned against the host, pioneering research on autoimmune diseases beginning in the early 1900s has documented a different reality. More than 80 different autoimmune disorders have now been described that may affect up to 5% of the population.

Russia tensions keep Arctic research on ice

Collaboration stifled as many scientists look to establish fieldwork elsewhere

Twist of fate

A physician-scientist has probed Parkinson’s disease for more than 30 years. Now, he has it

The Polarstern research vessel will spend 1 year locked in an Arctic ice floe. Aboard the ship and on the nearby ice, researchers will take measurements of the ice, air, water, and more in an effort to understand this pristine place. Science journalist Shannon Hall joins host Sarah Crespi to talk about her time aboard the Polarstern and how difficult these measurements are, when the researchers’ temporary Arctic home is the noisiest, smokiest, brightest thing around.

After that icy start, Sarah talks also with Tanmoy Samanta, a postdoctoral researcher at Peking University in Beijing, about the source of the extreme temperature of the Sun’s corona, which can be up to 1 million K hotter than the surface of the Sun. His team’s careful measurements of spicules—small, plentiful, short-lived spikes of plasma that constantly ruffle the Sun’s surface—and the magnetic networks that seem to generate these spikes, suggest a solution to the long-standing problem of how spicules arise and, at the same time, their likely role in the heating of the corona.