Stochastic cytokine expression induces mixed T helper cell States.
Stochastic cytokine expression induces mixed T helper cell States.
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DOI：
10.1371/journal.pbio.1001618
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发表时间：
2013-07
期刊：
影响因子：
9.8
通讯作者：
van Oudenaarden A
中科院分区：
文献类型：
--
作者：
Fang M;Xie H;Dougan SK;Ploegh H;van Oudenaarden A
在T辅助细胞的早期分化过程中，随机细胞因子的表达触发了高水平的拮抗转录因子的共同表达，并被细胞外和细胞内信号成分之间的相互作用所缓冲。在真核生物发育过程中，谱系特异性转录因子的诱导通常会驱动多能祖细胞的分化，而抑制可选谱系的分化。这一过程通常由一些细胞外信号分子介导，如细胞因子，可以结合细胞表面受体，导致转录因子的激活和/或抑制。我们通过计数单个细胞的单转录本和定量免疫荧光，探讨了初始CD4 T辅助细胞（Th）早期分化为Th1和Th2状态。与拮抗转录因子的互斥表达相反，我们观察到它们在单个细胞中普遍存在的高水平共表达，这与谱系启动过程中基础水平的共表达不同。我们观察到细胞因子仅在一小部分细胞亚群中表达，独立于这些单细胞中的转录因子表达。辅助T细胞分化早期细胞因子表达的细胞间差异明显大于完全分化状态。当细胞因子信号被抑制时，我们观察到典型的拮抗转录因子相互排斥，从而揭示了一个弱的细胞内网络，否则被细胞外细胞因子发出的强信号所取代。这些结果表明，在早期分化过程中，CD4 T细胞在细胞外细胞因子的指导下获得混合Th1/Th2状态。Th1/Th2分化过程中揭示的细胞外和细胞内信号相互作用可能是哺乳动物细胞缓冲嘈杂细胞因子表达的共同策略。在多细胞生物的发育过程中，祖细胞有可能成为具有特殊功能的几种不同细胞系中的任何一种，它们结合并分化成一个特定的细胞系。这种祖细胞的分化是由谱系特异性转录因子（调节基因表达的分子）的诱导所驱动的。这一过程通常由细胞外信号分子介导，包括一类称为细胞因子的分子，它们可以与细胞表面受体结合，激活和/或抑制转录因子。在这里，我们探索了幼稚T辅助细胞（Th）的早期分化，这是一类重要的T淋巴细胞，可以帮助效应免疫细胞保护身体免受各种病原体的侵害。我们测量了单个细胞中细胞因子和转录因子的mRNA和蛋白质水平。特别是，用单分子分辨率测量mRNA水平。与只表达一组谱系特异性转录因子相反，我们观察到在单个细胞中普遍存在高水平的拮抗转录因子共表达。我们发现细胞因子仅在一小部分细胞亚群中表达，独立于单个细胞中转录因子的表达。当细胞因子信号被抑制时，每个细胞只表达一种高水平的拮抗转录因子。这揭示了一个弱的细胞内网络，否则被细胞外细胞因子发出的强信号所推翻。这些结果表明，在早期分化过程中，T辅助细胞在细胞外细胞因子的指导下获得混合Th1/Th2状态。Th1/Th2分化过程中揭示的细胞外和细胞内信号相互作用可能是哺乳动物细胞缓冲嘈杂细胞因子表达的共同策略。
During early differentiation of T helper cells, stochastic cytokine expression triggers the co-expression of antagonistic transcription factors at high levels, buffered by the interplay between extracellular and intracellular signaling components. During eukaryotic development, the induction of a lineage-specific transcription factor typically drives differentiation of multipotent progenitor cells, while repressing that of alternative lineages. This process is often mediated by some extracellular signaling molecules, such as cytokines that can bind to cell surface receptors, leading to activation and/or repression of transcription factors. We explored the early differentiation of naive CD4 T helper (Th) cells into Th1 versus Th2 states by counting single transcripts and quantifying immunofluorescence in individual cells. Contrary to mutually exclusive expression of antagonistic transcription factors, we observed their ubiquitous co-expression in individual cells at high levels that are distinct from basal-level co-expression during lineage priming. We observed that cytokines are expressed only in a small subpopulation of cells, independent from the expression of transcription factors in these single cells. This cell-to-cell variation in the cytokine expression during the early phase of T helper cell differentiation is significantly larger than in the fully differentiated state. Upon inhibition of cytokine signaling, we observed the classic mutual exclusion of antagonistic transcription factors, thus revealing a weak intracellular network otherwise overruled by the strong signals that emanate from extracellular cytokines. These results suggest that during the early differentiation process CD4 T cells acquire a mixed Th1/Th2 state, instructed by extracellular cytokines. The interplay between extracellular and intracellular signaling components unveiled in Th1/Th2 differentiation may be a common strategy for mammalian cells to buffer against noisy cytokine expression. During the development of a multicellular organism, the progenitor cells, which have the potential to become any of several different cell lineages with specialized functions, commit and differentiate into one particular lineage. This differentiation of progenitors is driven by the induction of lineage-specific transcription factors, molecules that regulate gene expression. This process is often mediated by extracellular signaling molecules, including a class of molecules called cytokines that can bind to cell surface receptors, activating and/or repressing transcription factors. Here we explored the early differentiation of naive T helper (Th) cells, an important class of T lymphocytes that help effector immune cells to defend the body against various pathogens. We measured both mRNA and protein levels of cytokines and transcription factors in individual cells. In particular, mRNA levels were measured with single-molecule resolution. Contrary to the expression of only one set of lineage-specific transcription factors, we observed ubiquitous high-level co-expression of antagonistic transcription factors in individual cells. We found that cytokines are expressed only in a small subpopulation of cells, independent from the expression of transcription factors in individual cells. When cytokine signaling is inhibited, each cell expressed only one of the antagonistic transcription factors at high levels. This reveals a weak intracellular network that is otherwise overruled by the strong signals that emanate from extracellular cytokines. These results suggest that during the early differentiation process T helper cells acquire a mixed Th1/Th2 state, instructed by extracellular cytokines. The interplay between extracellular and intracellular signaling components unveiled in Th1/Th2 differentiation may be a common strategy for mammalian cells to buffer against noisy cytokine expression.
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影响因子：
32.4
作者：
Hegazy, Ahmed N.;Peine, Michael;Loehning, Max
通讯作者：
Loehning, Max
影响因子：
32.4
作者：
Laiosa, Catherine V.;Stadtfeld, Matthias;Graf, Thomas
通讯作者：
Graf, Thomas
影响因子：
56.9
作者：
Hwang, ES;Szabo, SJ;Glimcher, LH
通讯作者：
Glimcher, LH
影响因子：
4.4
作者：
Calado, Dinis Pedro;Paixao, Tiago;Haury, Matthias
通讯作者：
Haury, Matthias
DOI：
10.1073/pnas.0909357106
发表时间：
2009-10-20
影响因子：
11.1
作者：
Jenner, Richard G.;Townsend, Michael J.;Lord, Graham M.
通讯作者：
Lord, Graham M.