Lupus, or systemic lupus erythematosus, is an autoimmune disease characterized by the imbalance of activity between the effector and regulator helper T cells of the immune system. Researchers estimate that this chronic disease, which can cause damage to virtually any organ in the body, affects more than 1.5 million Americans, most often women between the ages of 15 and 44.
The magic ingredient in this treatment? Interleukin (IL)-2. In their study, researchers gave IL-2 to lupus patients who weren’t being helped with the existing lupus treatments, in much lower doses than administered to patients when the treatment was used to treat cancer.
“It calms the hyperactive immune system through multiple mechanisms,” said Professor Eric Morand, founder of the Asia Pacific Lupus Collaboration. “This new therapy may be effective for many patients.”
IL-2 is a cytokine, a signaling molecule produced by immune cells for immune cells. Specifically, IL-2 modulates homeostasis of CD4+ T cells by regulating the abundance of regulatory T cells, follicular helper T cells, and IL-17-producing helper T cells. Follicular helper T cells are the “specialized providers of B cell help,” meaning they regulate the germinal center that produce antibody-creating plasma cells and memory B cells. IL-17-producing helper T cells play a vital role in the pathogenesis of autoimmune diseases, like lupus. Specifically, these cells facilitate the inflammatory process through stimulation of cytokines, chemokines, neutrophils, and macrophages.
Patients with lupus show reduced production of IL-2 by T cells, suggesting that an IL-2 deficiency is at the root of their immune dysfunction.
With the initial success of these IL-2 studies, clinical trials will soon be underway. Scientists are hopeful for the quick approval of this new treatment, since preclinical trials have shown the IL-2 treatment to be effective and safe for treating lupus, and higher doses of the drug have been approved in the past.
The present study was recently published in the journal Nature Medicine.
Sources: Monash University, European Journal of Immunology, Annual Review of Immunology