PDF(Pubmed)
Abstract：
Extracellular vesicles (EVs), transporting diverse cellular components, play a crucial role in intercellular communication in numerous physiological and pathological processes. EVs have also been recognized as a drug delivery platform for therapeutic purposes and cell-free regenerative medicine. While various approaches have focused on increasing EV production for efficient use therapeutic use of EVs, enhancing the quality of EVs, such as ensuring efficient uptake by their target cells, has not been widely explored. In this study, we linked a negative membrane curvature-forming inverse BAR (IBAR) domain with an integrin β tail-binding talin F3 domain to create the IBAR-F3 fusion protein. We observed that IBAR-F3 can trigger filopodia-like membrane protrusions and attract integrins to those protrusion-rich regions, when expressed in Chinese hamster ovary cells expressing integrin αIIbβ3. Surprisingly, the expression of IBAR-F3 also induced a robust production of EVs, which were then efficiently taken up by nearby cells in an integrin-dependent manner. Moreover, IBAR triggered integrin activation, presumably by inducing negative membrane curvature that likely disrupts the interaction between the integrin α and β transmembrane domain. Therefore, we suggest that IBAR-F3 should be utilized to promote both EV production and efficient uptake mediated by integrins. Furthermore, the negative curvature-inducing integrin activation suggests that integrins on EVs can be activated by the nanoscale change in the curvature of the EV without the need for conventional machinery to activate integrin inside the EVs.
摘要：
细胞外囊泡（EV），运输不同的细胞成分，在许多生理和病理过程中，在细胞间通讯中起着至关重要的作用。EV也被认为是用于治疗目的和无细胞再生医学的药物递送平台。虽然各种方法都集中在增加电动汽车产量，以有效使用电动汽车的治疗用途，提高电动汽车的质量，例如确保靶细胞的有效摄取，尚未被广泛探索。在这项研究中,我们将负膜曲率形成反向BAR（IBAR）结构域与整合素β尾结合滑石F3结构域连接，以创建IBAR-F3融合蛋白。我们观察到IBAR-F3可以触发丝状类膜突起，并将整合素吸引到那些富含突起的区域，当在表达整合素αIIbβ3的中国仓鼠卵巢细胞中表达时。令人惊讶的是,IBAR-F3的表达也诱导了电动汽车的强劲产生，然后被附近细胞以整合素依赖性方式有效吸收。此外，IBAR触发整合素激活，推测是通过诱导可能破坏整合素α和β跨膜结构域之间的相互作用的负膜曲率。因此,我们建议IBAR-F3应用于促进EV的产生和整合素介导的有效摄取。此外，负曲率诱导的整合素激活表明，电动汽车上的整合素可以通过电动汽车曲率的纳米级变化来激活，而无需常规机械来激活电动汽车内的整合素。
