期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2020
卷号：117
期号：29
页码：17156-17165
DOI：10.1073/pnas.2001665117
出版社：The National Academy of Sciences of the United States of America
摘要：Semi-invariant natural killer T (iNKT) cells are self-reactive lymphocytes, yet how this lineage attains self-tolerance remains unknown. iNKT cells constitutively express high levels of Nr4a1 -encoded Nur77, a transcription factor that integrates signal strength downstream of the T cell receptor (TCR) within activated thymocytes and peripheral T cells. The function of Nur77 in iNKT cells is unknown. Here we report that sustained Nur77 overexpression (Nur77 tg ) in mouse thymocytes abrogates iNKT cell development. Introgression of a rearranged Vα14-Jα18 TCR-α chain gene into the Nur77 tg (Nur77 tg ;Vα14 tg ) mouse rescued iNKT cell development up to the early precursor stage, stage 0. iNKT cells in bone marrow chimeras that reconstituted thymic cellularity developed beyond stage 0 precursors and yielded IL-4–producing NKT2 cell subset but not IFN-γ–producing NKT1 cell subset. Nonetheless, the developing thymic iNKT cells that emerged in these chimeras expressed the exhaustion marker PD1 and responded poorly to a strong glycolipid agonist. Thus, Nur77 integrates signals emanating from the TCR to control thymic iNKT cell tolerance induction, terminal differentiation, and effector functions.
