Abstract
Advances in our understanding of the pathogenesis of primary Sjögren syndrome (pSS) characterize it as a highly complex process encompassing both the initiation of innate immunity and subsequent adaptive immune responses. IL-21 is receiving attention as a potential key player in the pathogenesis of pSS owing to its pleiotropic effects on the type I interferon signalling pathway, and newly identified roles in generation of follicular and IL-17-producing subtypes of helper T cells, as well as plasma-cell differentiation and B-cell activation. Taking into consideration the diverse biological functions of IL-21 and its clinical relevance to pSS, we propose that this cytokine has a central role in orchestrating the complex immune response in pSS. This hypothesis might provide new insight into the pathogenesis of pSS and facilitate the development of effective therapeutic strategies.
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Acknowledgements
The authors' research work is supported by the Basic Science Research Program, through the National Research Foundation of Korea (NRF), funded by the Ministry of Science, ICT & Future Planning (grant 2013R1A1A2059368 to H.-Y.-K.).
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S.-K.K. and J.L. contributed equally to this article. S.-K.K., J.L., D.Y., H.-R.K. and H.-Y.K. participated in researching the data for the article, discussions of its content, writing the manuscript, and reviewing and/or editing of the manuscript before submission. K.Y.K. M.-L.C., J.H.J., S.-H.L. and S.-H.P. contributed to discussions of the article content and review or editing of the manuscript before submission.
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Kwok, SK., Lee, J., Yu, D. et al. A pathogenetic role for IL-21 in primary Sjögren syndrome. Nat Rev Rheumatol 11, 368–374 (2015). https://doi.org/10.1038/nrrheum.2014.225
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DOI: https://doi.org/10.1038/nrrheum.2014.225
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