Molecular Immunology-Institute for Immunology, University Hospital Schleswig-Holstein, Campus Kiel, 24105 Kiel, Germany.
Systematic Proteomics & Bioanalytics-Institute for Experimental Medicine, University of Kiel, 24105 Kiel, Germany.
Cells. 2024 Oct 21;13(20):1745. doi: 10.3390/cells13201745.
Although belonging to different branches of the immune system, cytotoxic CD8 αβ T cells and γδ T cells utilize common cytolytic effectors including FasL, granzymes, perforin and granulysin. The effector proteins are stored in different subsets of lysosome-related effector vesicles (LREVs) and released to the immunological synapse upon target cell encounter. Notably, in activated cells, LREVs and potentially other vesicles are continuously produced and released as extracellular vesicles (EVs). Presumably, EVs serve as mediators of intercellular communication in the local microenvironment or at distant sites.
EVs of activated and expanded cytotoxic CD8 αβ T cells or γδ T cells were enriched from culture supernatants by differential and ultracentrifugation and characterized by nanoparticle tracking analyses and Western blotting. For a comparative proteomic profiling, EV preparations from both cell types were isobaric labeled with tandem mass tags (TMT10plex) and subjected to mass spectrometry analysis.
686 proteins were quantified in EV preparations of cytotoxic CD8 αβ T cells and γδ T cells. Both populations shared a major set of similarly abundant proteins, while much fewer proteins presented higher abundance levels in either CD8 αβ T cells or γδ T cells. To our knowledge, we provide the first comparative analysis of EVs from cytotoxic CD8 αβ T cells and γδ T cells.
尽管细胞毒性 CD8αβT 细胞和 γδT 细胞属于免疫系统的不同分支，但它们利用包括 FasL、颗粒酶、穿孔素和颗粒溶素在内的共同细胞毒性效应器。效应蛋白储存在溶酶体相关效应囊泡（LREV）的不同亚群中，并在遇到靶细胞时释放到免疫突触中。值得注意的是，在激活的细胞中，LREV 和潜在的其他囊泡作为细胞外囊泡（EVs）不断产生和释放。推测 EVs 作为局部微环境或远处部位细胞间通讯的介质。
通过差速和超速离心从激活和扩增的细胞毒性 CD8αβT 细胞或 γδT 细胞的培养上清液中富集 EVs，并通过纳米颗粒跟踪分析和 Western blot 进行表征。为了进行比较蛋白质组学分析，两种细胞类型的 EV 制剂均用串联质量标签（TMT10plex）进行等压标记，并进行质谱分析。
在细胞毒性 CD8αβT 细胞和 γδT 细胞的 EV 制剂中定量了 686 种蛋白质。这两个群体共享一大组类似丰富的蛋白质，而在 CD8αβT 细胞或 γδT 细胞中，只有更少的蛋白质呈现更高的丰度水平。据我们所知，我们首次对细胞毒性 CD8αβT 细胞和 γδT 细胞的 EVs 进行了比较分析。
