Low-Dose Interleukin-2 Therapy: A Driver of an Imbalance between Immune Tolerance and Autoimmunity
AbstractFor many years, the role of interleukin-2 (IL-2) in autoimmune responses was established as a cytokine possessing strong pro-inflammatory activity. Studies of the past few years have changed our knowledge on IL-2 in autoimmune chronic inflammation, suggesting its protective role, when administered at low-doses. The disrupted balance between regulatory and effector T cells (Tregs and Teffs, respectively) is a characteristic of autoimmune diseases, and is dependent on homeostatic cytokines, including IL-2. Actually, inherent defects in the IL-2 signaling pathway and/or levels leading to Treg compromised function and numbers as well as Th17 expansion have been attributed to autoimmune disorders. In this review, we discuss the role of IL-2 in the pathogenesis of autoimmune diseases. In particular, we highlight the impact of the dysregulated IL-2 pathway on disruption of the Treg/Th17 balance, reversal of which appears to be a possible mechanism of the low-dose IL-2 treatment. The negative effects of IL-2 on the differentiation of follicular helper T cells (Tfh) and pathogenic Th17 cells, both of which contribute to autoimmunity, is emphasized in the paper as well. We also compare the current IL-2-based therapies of animal and human subjects with immune-mediated diseases aimed at boosting the Treg population, which is the most IL-2-dependent cell subset desirable for sufficient control of autoimmunity. New perspectives of therapeutic approaches focused on selective delivery of IL-2 to inflamed tissues, thus allowing local activity of IL-2 to be combined with its reduced systemic and pleiotropic toxicity, are also proposed in this paper. View Full-Text
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Kosmaczewska, A. Low-Dose Interleukin-2 Therapy: A Driver of an Imbalance between Immune Tolerance and Autoimmunity. Int. J. Mol. Sci. 2014, 15, 18574-18592.
Kosmaczewska A. Low-Dose Interleukin-2 Therapy: A Driver of an Imbalance between Immune Tolerance and Autoimmunity. International Journal of Molecular Sciences. 2014; 15(10):18574-18592.Chicago/Turabian Style
Kosmaczewska, Agata. 2014. "Low-Dose Interleukin-2 Therapy: A Driver of an Imbalance between Immune Tolerance and Autoimmunity." Int. J. Mol. Sci. 15, no. 10: 18574-18592.