After receiving an experimental treatment to prevent the body from attacking itself, five people no longer have any symptoms of lupus.
That treatment, called CAR-T cell therapy, appears to have restored the patients’ immune systems, send your autoimmune disease into remissionresearchers report on September 15 in Natural medicine. It is not yet clear how long the relief will last or if the therapy will work for all patients.
Still, the results could be “revolutionary,” says immunologist Linrong Lu of the Shanghai Institute of Immune Therapy at Shanghai Jiao Tong University School of Medicine, who was not involved in the study. CAR-T cell therapy it has been used for several types of cancer, but is still being tested for autoimmune diseases (Serial number: 2/2/22).
In the new study, all five participants went into remission without the need for additional drugs beyond the genetically modified CAR-T cells. The target of those modified cells — key immune cells for fighting infection — returned a few months after they were removed. Some of those cells are primed to attack viruses and bacteria, but not the healthy cells of the study participants.
It is unknown how many people worldwide have lupus, a painful disease in which some immune proteins called antibodies attack healthy tissues and organs (Serial number: 04/25/19). It is estimated that between 161,000 and 322,000 people in the United States are living with the most common form called systemic lupus erythematosus. While there are effective therapies, those treatments don’t work for everyone.
All five people in the study had this common form with symptoms resistant to multiple commonly used lupus drugs, such as hydroxychloroquine. But laboratory studies in mice hinted that CAR-T cells might help. So immunologist Georg Schett and his colleagues took T cells from each patient and genetically modified the cells to track down and kill all the antibody-producing cells. The five participants, four women and one man aged 18 to 24, were in remission three months after being treated with the altered cells.
The antibody-producing cells, called B cells, disappeared from the blood samples when CAR-T cells killed them. But B cells are an important defense against infectious diseases like measles. Fortunately, the immune cells did not disappear permanently, says Schett, of the Friedrich-Alexander-Universität Erlangen-Nürnberg in Germany. A few months later, the patients’ bone marrow had produced more. The B cells had returned; lupus was not.
“Which means, in a way, that we have a reset of the immune system in these young people,” says Schett.
Typically, the immune system has checkpoints that eliminate attacking cells from the body rather than a foreign invader. Autoimmune diseases like lupus occur when these self-recognizing and self-attacking cells escape scrutiny. For lupus to come back, says Schett, the same mistake may have to happen twice. “So far we think the disease is gone.”
To be sure, the team needs more time to follow the participants. In August 2021, the researchers reported in the New England Journal of Medicine that the first treated participant, a 20-year-old woman, was in remission three months after receiving the drug. Now, that patient has been healthy for a year and a half, says Schett. The other four have been healthy for six months to a year. Time will tell how long these people will remain lupus free.
It is not yet clear which people might benefit most from CAR-T cell therapy. The symptoms and severity of lupus vary from person to person. The treatment might, for example, be more helpful for patients who are in the early stages of the disease before it becomes too severe, says Lu. Still, if future clinical trials prove effective, CAR-T cell therapy could be another way to offer hope to patients with the disease.