Induction of autoimmune diabetes in non-obese diabetic mice requires interleukin-21-dependent activation of autoreactive CD8⁺ T cells. Clin Exp Immunol 2013 Aug;173(2):184-94
Date
04/24/2013Pubmed ID
23607664Pubmed Central ID
PMC3722919DOI
10.1111/cei.12108Scopus ID
2-s2.0-84880021592 (requires institutional sign-in at Scopus site) 13 CitationsAbstract
Non-obese diabetic (NOD) mice lacking interleukin (IL)-21 or IL-21 receptor do not develop autoimmune type 1 diabetes (T1D). We have shown recently that IL-21 may promote activation of autoreactive CD8(+) T cells by increasing their antigen responsiveness. To investigate the role of IL-21 in activating diabetogenic CD8(+) T cells in the NOD mouse, we generated IL-21-deficient NOD mice expressing the highly pathogenic major histocompatibility complex (MHC) class-I-restricted 8.3 transgenic T cell receptor (TCR). IL-21 deficiency protected 8.3-NOD mice completely from T1D. CD8(+) T cells from the 8.3-NOD.Il21(-/-) mice showed decreased antigen-induced proliferation but displayed robust antigen-specific cytolytic activity and production of effector cytokines. IL-21-deficient 8.3 T cells underwent efficient homeostatic proliferation, and previous antigen stimulation enabled these cells to cause diabetes in NOD.Scid recipients. The 8.3 T cells that developed in an IL-21-deficient environment showed impaired antigen-specific proliferation in vivo even in IL-21-sufficient mice. These cells also showed impaired IL-2 production and Il2 gene transcription following antigen stimulation. However, IL-2 addition failed to reverse their impaired proliferation completely. These findings indicate that IL-21 is required for efficient initial activation of autoreactive CD8(+) T cells but is dispensable for the activated cells to develop effector functions and cause disease. Hence, therapeutic targeting of IL-21 in T1D may inhibit activation of naive autoreactive CD8(+) T cells, but may have to be combined with other strategies to inhibit already activated cells.
Author List
Chen XL, Bobbala D, Rodriguez GM, Mayhue M, Chen YG, Ilangumaran S, Ramanathan SAuthor
Yi-Guang Chen PhD Professor in the Pediatrics department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsAutoantigens
CD8-Positive T-Lymphocytes
Cell Proliferation
Cells, Cultured
Cytotoxicity, Immunologic
Diabetes Mellitus, Type 1
Interleukins
Lymphocyte Activation
Mice
Mice, Inbred NOD
Mice, Knockout
Mice, Transgenic
Molecular Targeted Therapy
Receptors, Antigen, T-Cell