Although cigarette smoke is known to alter immune responses, whether and how CD4 T cells are affected is not well-described. We aimed to characterize how exposure to cigarette smoke extract impacts CD4 T cell effector generation in vitro under Th1-polarizing conditions. Our results demonstrate that cigarette smoke directly acts on CD4 T cells to impair effector expansion by decreasing division and increasing apoptosis. Furthermore, cigarette smoke enhances Th1-associated cytokine production and increases expression of the transcription factor T-bet, the master regulator of Th1 differentiation. Finally, we show that exposure to cigarette smoke extract during priming impairs the ability of effectors to form memory cells. Our findings thus demonstrate that cigarette smoke simultaneously enhances effector functions but promotes terminal differentiation of CD4 T cell effectors. This study may be relevant to understanding how smoking can both aggravate autoimmune symptoms and reduce vaccine efficacy.

中文翻译：

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香烟烟雾提取物直接作用于 CD4 T 细胞，增强 Th1 极化并降低记忆潜力。


尽管已知香烟烟雾会改变免疫反应，但 CD4 T 细胞是否以及如何受到影响尚不清楚。我们的目的是表征在 Th1 极化条件下暴露于香烟烟雾提取物如何影响体外 CD4 T 细胞效应子的产生。我们的结果表明，香烟烟雾直接作用于 CD4 T 细胞，通过减少分裂和增加细胞凋亡来损害效应器扩张。此外，香烟烟雾还能增强 Th1 相关细胞因子的产生，并增加转录因子 T-bet（Th1 分化的主要调节因子）的表达。最后，我们发现在启动过程中接触香烟烟雾提取物会损害效应器形成记忆细胞的能力。因此，我们的研究结果表明，香烟烟雾同时增强效应器功能，但促进 CD4 T 细胞效应器的终末分化。这项研究可能有助于了解吸烟如何加重自身免疫症状并降低疫苗功效。