Loss of immune tolerance to IL-2 in type 1 diabetes

Nom de la revue
Nature Communications
Louis Pérol, John M. Lindner, Pamela Caudana, Nicolas Gonzalo Nunez, Audrey Baeyens, Andrea Valle, Christine Sedlik, Delphine Loirat, Olivier Boyer, Alain Créange, José Laurent Cohen, Ute Christine Rogner, Jun Yamanouchi, Martine Marchant, Xavier Charles Leber, Meike Scharenberg, Marie-Claude Gagnerault, Roberto Mallone, Manuela Battaglia, Pere Santamaria, Agnès Hartemann, Elisabetta Traggiai, Eliane Piaggio

AbstractType 1 diabetes (T1D) is characterized by a chronic, progressive autoimmune attack against pancreas-specific antigens, effecting the destruction of insulin-producing β-cells. Here we show interleukin-2 (IL-2) is a non-pancreatic autoimmune target in T1D. Anti-IL-2 autoantibodies, as well as T cells specific for a single orthologous epitope of IL-2, are present in the peripheral blood of non-obese diabetic (NOD) mice and patients with T1D. In NOD mice, the generation of anti-IL-2 autoantibodies is genetically determined and their titre increases with age and disease onset. In T1D patients, circulating IgG memory B cells specific for IL-2 or insulin are present at similar frequencies. Anti-IL-2 autoantibodies cloned from T1D patients demonstrate clonality, a high degree of somatic hypermutation and nanomolar affinities, indicating a germinal centre origin and underscoring the synergy between cognate autoreactive T and B cells leading to defective immune tolerance.