Saturday, March 06, 2021

A LOT Of Obesity Is An Inflammatory Autoimmune Disorder

khn  |  There’s a reason soldiers go through basic training before heading into combat: Without careful instruction, green recruits armed with powerful weapons could be as dangerous to one another as to the enemy.

The immune system works much the same way. Immune cells, which protect the body from infections, need to be “educated” to recognize bad guys — and to hold their fire around civilians.

In some covid patients, this education may be cut short. Scientists say unprepared immune cells appear to be responding to the coronavirus with a devastating release of chemicals, inflicting damage that may endure long after the threat has been eliminated.

“If you have a brand-new virus and the virus is winning, the immune system may go into an ‘all hands on deck’ response,” said Dr. Nina Luning Prak, co-author of a January study on covid and the immune system. “Things that are normally kept in close check are relaxed. The body may say, ‘Who cares? Give me all you’ve got.’”

While all viruses find ways to evade the body’s defenses, a growing field of research suggests that the coronavirus unhinges the immune system more profoundly than previously realized.

Some covid survivors have developed serious autoimmune diseases, which occur when an overactive immune system attacks the patient, rather than the virus. Doctors in Italy first noticed a pattern in March 2020, when several covid patients developed Guillain-Barré syndrome, in which the immune systems attacks nerves throughout the body, causing muscle weakness or paralysis. As the pandemic has surged around the world, doctors have diagnosed patients with rare, immune-related bleeding disorders. Other patients have developed the opposite problem, suffering blood clots that can lead to stroke.

All these conditions can be triggered by “autoantibodies” — rogue antibodies that target the patient’s own proteins and cells.

In a report published in October, researchers even labeled the coronavirus “the autoimmune virus.”

“Covid is deranging the immune system,” said John Wherry, director of the Penn Medicine Immune Health Institute and another co-author of the January study. “Some patients, from their very first visit, seem to have an immune system in hyperdrive.”