Toll-Like Receptor 4 Triggering Promotes Cytosolic Routing of DC-SIGN-Targeted Antigens for Presentation on MHC Class I

Frontiers in Immunology

Karien Bloem¹  Hakan Kalay²  Sandra J. van Vliet²  Yvette van Kooyk²  Sophie K. Horrevorts²  Sanne Duinkerken²  Juan J. García-Vallejo²  René J. Musters³  Pablo Secades⁴ 

[1] Centre for Specialized Nutrition, Danone Research, Wageningen, Netherlands;Department of Molecular Cell Biology and Immunology, Cancer Center Amsterdam, VU University Medical Center, Amsterdam, Netherlands;Department of Physiology, VU University Medical Center, Amsterdam, Netherlands;Division of Cell Biology, Dutch Cancer Institute, Amsterdam, Netherlands;

关键词: dendritic cells;    DC-SIGN;    cross-presentation;    imaging flow cytometry;    toll-like receptor;    MHC-I;   

DOI  :  10.3389/fimmu.2018.01231

来源: DOAJ

【 摘 要 】

DC-SIGN is an antigen uptake receptor expressed on dendritic cells (DCs) with specificity for glycans present on a broad variety of pathogens and is capable of directing its cargo to MHC-I and MHC-II pathways for the induction of CD8+ and CD4+ T cell responses, respectively. Therefore, DC-SIGN is a very promising target for the delivery of antigen for anti-cancer vaccination. Although the endocytic route leading to MHC-II presentation is characterized to a large extent, the mechanisms controlling DC-SIGN targeted cross-presentation of exogenous peptides on MHC-I, are not completely resolved yet. In this paper, we used imaging flow cytometry and antigen-specific CD8+ T cells to investigate the intracellular fate of DC-SIGN and its cargo in human DCs. Our data demonstrates that immature DCs and toll-like receptor 4 (TLR4) stimulated DCs had similar internalization capacity and were both able to cross-present antigen targeted via DC-SIGN. Interestingly, simultaneous triggering of TLR4 and DC-SIGN on DCs resulted in the translocation of cargo to the cytosol, leading to proteasome-dependent processing and increased CD8+ T cell activation. Understanding the dynamics of DC-SIGN-mediated uptake and processing is essential for the design of optimal DC-SIGN-targeting vaccination strategies aimed at enhancing CD8+ T cell responses.

【 授权许可】

Unknown