Chen Chien-Chia, Hung Tzu-Min, Huang Yi-Jen, Hung Hsu-Shan, Hu Chun-Mei, Lee Po-Huang
Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan.
Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan; Department of Medical Research, E-Da Hospital, Kaohsiung, Taiwan.
Biomed Pharmacother. 2025 Jan;182:117765. doi: 10.1016/j.biopha.2024.117765. Epub 2024 Dec 16.
Extracellular vesicles (EVs) derived from T cells have been proposed to mediate intercellular communication and orchestrate immune responses. The immunosuppressive drug, tacrolimus (TAC), suppresses T cell activity; however, the impact of TAC on T cell-derived EVs remains primarily unexplored. In this study, human primary T cells purified from healthy donors were used to investigate TAC-mediated regulation of EV secretion by T cells. Using size exclusion chromatography (SEC) to isolate EVs released by T cells, we found that the number of released EVs was increased upon anti-CD3/CD28 bead-mediated activation. Furthermore, pre-treatment with TAC before activation had a potentiating effect on EV release, as evidenced by western blot analysis of EV markers and small particle flow cytometry. In addition, we showed that EVs isolated from the plasma of TAC-treated kidney transplant patients were increased compared to those observed with pre-transplant plasma. Upon examining the mechanism underlying the action of TAC, we found that TAC impaired autophagy-lysosome-mediated degradation by inhibiting the nuclear translocation of transcription factor EB, a master regulator of lysosomal biogenesis. Notably, the addition of trehalose, an autophagy inducer, abrogated the TAC-induced EV release, indicating that TAC regulated EV secretion via the autophagy-lysosomal pathway. At the functional level, we demonstrated that EVs from TAC-treated T cells carried a decreased amount of CD40L, a protein critical for the activation of the adaptive immune response. Collectively, these findings demonstrate that an overall increase in EV production and decreased CD40L levels in EVs are characteristic responses of T cells to TAC.
源自T细胞的细胞外囊泡（EVs）被认为可介导细胞间通讯并协调免疫反应。免疫抑制药物他克莫司（TAC）可抑制T细胞活性；然而，TAC对T细胞衍生的EVs的影响仍主要未被探索。在本研究中，使用从健康供体纯化的人原代T细胞来研究TAC介导的T细胞对EV分泌的调节作用。利用尺寸排阻色谱法（SEC）分离T细胞释放的EVs，我们发现抗CD3/CD28磁珠介导的激活后，释放的EVs数量增加。此外，激活前用TAC预处理对EV释放有增强作用，这通过对EV标志物的蛋白质印迹分析和小颗粒流式细胞术得到证实。此外，我们表明，与移植前血浆相比，从接受TAC治疗的肾移植患者血浆中分离的EVs有所增加。在研究TAC作用的潜在机制时，我们发现TAC通过抑制转录因子EB（溶酶体生物发生的主要调节因子）的核转位来损害自噬-溶酶体介导的降解。值得注意的是，添加自噬诱导剂海藻糖可消除TAC诱导的EV释放，表明TAC通过自噬-溶酶体途径调节EV分泌。在功能水平上，我们证明来自TAC处理的T细胞的EVs携带的CD40L量减少，CD40L是激活适应性免疫反应的关键蛋白质。总的来说，这些发现表明，EV产生的总体增加和EV中CD40L水平的降低是T细胞对TAC的特征性反应。
