کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5591927 1570705 2017 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Immature human DCs efficiently translocate endocytosed antigens into the cytosol for proteasomal processing
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی زیست شناسی مولکولی
پیش نمایش صفحه اول مقاله
Immature human DCs efficiently translocate endocytosed antigens into the cytosol for proteasomal processing
چکیده انگلیسی
Cross-presentation of endocytosed antigen is essential for induction of CD8 effector T cell responses and a hallmark of dendritic cells (DCs). The mode of antigen processing in this context is controversial and some models imply translocation of the antigen from the endosomes into the cytosol. To test this hypothesis we made use of the pro-apoptotic properties of cytochrome c when in the cytosol, and confirmed that it indeed triggered apoptosis of human immature DCs but only at high concentrations. Proteasome inhibitors reduced the required concentration of cytochrome c thousand-fold, indicating that protein translocated into the cytosol is rapidly degraded by proteasomes. Mature DCs were also susceptible to cytochrome c-triggered apoptosis at high concentrations but proteasome inhibitors did not increase their sensitivity. Other cross-presenting cells such as B cells and monocytes were not sensitive to cytochrome c at all, indicating that they do not shuttle internalized antigen into the cytosol. Thus, processing of internalized antigens seems to follow different pathways depending on cell type and, in case of DCs, maturation state. Immature DCs appear to have a unique capacity to shuttle external antigen into the cytosol for proteasomal processing, which could explain their efficiency in antigen cross-presentation.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Molecular Immunology - Volume 88, August 2017, Pages 148-154
نویسندگان
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