There are more than 100 autoimmune diseases, and they mostly strike women. Here’s what to know

Our immune system has a dark side: It’s supposed to fight off invaders to keep us healthy. But sometimes it turns traitor and attacks our own cells and tissues.

What are called autoimmune diseases can affect just about every part of the body – and tens of millions of people. While most common in women, these diseases can strike anyone, adults or children, and they’re on the rise.

New research is raising the prospect of treatments that might do more than tamp down symptoms. Dozens of clinical trials are testing ways to reprogram an immune system-gone-rogue, with some promising early successes against lupus, myositis and certain other illnesses. Other researchers are hunting ways to at least delay brewing autoimmune diseases, spurred by a drug that can buy some time before people show symptoms of Type 1 diabetes.

“This is probably the most exciting time that we’ve ever had to be