Lupus, also known as systemic lupus erythematosus, is caused by an erroneous reaction of the immune system against the DNA of people. It is driven by B cells producing antibodies against DNA released by dying cells. It is currently treated with drugs that suppress the immune system or, in more severe cases, with drugs that kill the B cells. However, the treatments cannot kill all the B cells, and if the disease worsens, some people develop kidney failure and inflammation of the heart and brain. However, CAR T-cell therapy has put all five people with lupus treated so far into remission. The participants were followed for an average of 8 months, with the first person treated 17 months ago. CAR T cells were barely detectable after one month, and after three and a half months, the volunteers’ B cells began to return, having been produced by bone marrow stem cells. These new B cells did not react against the DNA. Researchers don’t know what normally causes B cells to react against DNA in people with lupus, so it’s possible that some kind of trigger could restart the process. This realization means that CAR T cells may also be useful against other antibody-driven autoimmune diseases, such as multiple sclerosis, in which the immune system attacks nerves.
