Adjuvants enhancing cross-presentation by dendritic cells: the key to more effective vaccines?
- 1Radiotherapy and OncoImmunology Laboratory, Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Netherlands
- 2Department of Anesthesiology, Pain and Palliative Medicine, Radboud University Medical Center, Netherlands
Over the last decades, vaccine development has advanced significantly in pursuing higher safety with less side effects. However, this is often accompanied by a reduction in vaccine immunogenicity and an increased dependency on adjuvants to enhance vaccine potency. Especially for diseases like cancer, it is important that therapeutic vaccines contain adjuvants that promote strong T cell responses. An important mode of action for such adjuvants is to prolong antigen exposure to dendritic cells (DCs) and to induce their maturation. These mature DCs are extremely effective in the activation of antigen-specific T cells, which is a prerequisite for induction of potent and long-lasting cellular immunity. For the activation of CD8+ cytotoxic T cell responses, however, the exogenous vaccine antigens need to gain access to the endogenous MHCI presentation pathway of DCs, a process referred to as antigen cross-presentation. In this review we will focus on recent insights in clinically relevant vaccine adjuvants that impact DC cross-presentation efficiency, including aluminum-based nanoparticles, saponin-based adjuvants, and Toll-like receptor ligands. Furthermore, we will discuss the importance of adjuvant combinations and highlight new developments in cancer vaccines. Understanding the mode of action of adjuvants in general and on antigen cross-presentation in DCs in particular, will be important for the design of novel adjuvants as part of vaccines able to induce strong cellular immunity.
Keywords: adjuvants, dendritic cell, cross-presentation, Aluminum, saponin, TLR, Vaccine
Received: 08 Oct 2018;
Accepted: 22 Nov 2018.
Edited by:Sandra Tuyaerts, KU Leuven, Belgium
Reviewed by:Sandra S. Diebold, King's College London, United Kingdom
Irina Caminschi, Monash University, Australia
Copyright: © 2018 Ho, Huis in 't Veld, Raaijmakers and Adema. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
* Correspondence: Prof. Gosse J. Adema, Radiotherapy and OncoImmunology Laboratory, Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen, Netherlands, firstname.lastname@example.org