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bioRxiv · 10.1101/2022.08.14.503916

Plasticity and lineage commitment of individual Th1 cells are determined by stable T-bet expression quantities

Abstract

T helper 1 (Th1) cell identity is defined by the expression of the lineage-defining transcription factor T-bet. Here, we examine the influence of T-bet expression heterogeneity on subset plasticity by leveraging cell sorting of distinct in vivo-differentiated Th1 cells based on their quantitative expression of T-bet and interferon-{gamma}. Heterogeneous T-bet expression states were regulated by virus-induced type-I interferons and were stably maintained even after secondary viral infection. Exposed to Th2-polarizing conditions, the sorted subpopulations exhibited graded levels of plasticity: T-bet quantities were inversely correlated with the ability to express the Th2 lineage-specifying transcription factor GATA-3 and Th2 cytokines. Reprogramed Th1 cells acquired graded, but stable mixed Th1+2 phenotypes with a hybrid epigenetic landscape. Continuous presence of T-bet in differentiated Th1 cells was essential to ensure Th1 cell stability. Thus, innate cytokine signals regulate Th1 cell plasticity via an individual cell-intrinsic rheostat to enable T cell subset adaptation to subsequent challenges. HIGHLIGHTSO_LIType-I interferons triggered by infection determine T-bet expression states in Th1 cells C_LIO_LIT-bet and IFN-{gamma} expression states indicate the plasticity of individual Th1 cells C_LIO_LIIndividual T-bet expression states and plasticity persist after secondary infection C_LIO_LIReprogramming yields stable Th1+2 phenotypes and a mixed epigenetic landscape C_LI

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BibTeXRIS

Hegazy, A. N., Peine, C., Niesen, D., Panse, I., Vainshtein, Y., Kommer, C., Zhang, Q., Brunner, T. M., Peine, M., Froehlich, A., Ishaque, N., Marek, R. M., Zhu, J. J., Hoefer, T., Loehning, M.. 2022-08-15. Plasticity and lineage commitment of individual Th1 cells are determined by stable T-bet expression quantities. https://doi.org/10.1101/2022.08.14.503916

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