International Immunology Advance Access originally published online on April 11, 2005
International Immunology 2005 17(5):621-635; doi:10.1093/intimm/dxh243
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Optimizing the exogenous antigen loading of monocyte-derived dendritic cells
1 Department of Dermatology, University Hospital Erlangen, Erlangen, Germany
2 Cellectis SA, Paris, France
3 Department of Medicine, University of the Saarland, Homburg, Germany
4 Merus BV, Utrecht, The Netherlands
Correspondence to: D. Dieckmann; E-mail: detlef.dieckmann{at}derma.imed.uni-erlangen.de
Dendritic cell (DC) vaccination, i.e. the adoptive transfer of antigen-loaded DC, is still at an early stage and requires standardization. In this study, we investigated the exogenous loading of monocyte-derived DCs with HLA class I- and II-restricted peptides, as despite widespread use, little effort has been put into its pre-clinical validation. We found that only mature DCs (m-DC) but not immature DCs (im-DC) could be sufficiently loaded with exogenous class I-restricted peptides and were by far superior in expanding CD8+ primary (Melan-A.A2 peptide-specific) and recall [Influenza matrix peptide (IMP) A2-specific] T cell responses. Primary stimulation with peptide-loaded im-DCs even down-regulated antigen-specific T cell responses. Our results indicate that stimulation with m-DCs is superior in terms of quantity and quality compared with im-DCs, supporting their preferred use in clinical DC trials. Loading of m-DCs with high (10 µM) concentrations generated clearly more Melan-A effectors than loading with 1 or 0.1 µM without any negative effect on the quality (affinity) of the resulting T cells. In contrast to the findings with the Melan-A peptide loading with 10 µM IMP was counter-productive, induced apoptosis and yielded fewer specific T cells of inferior affinity as compared with loading with 1 or 0.1 µM. In sharp contrast to the situation for HLA class I, much higher levels and longer half-lives of peptide–HLA class II complexes were obtainable upon loading of im-DCs with exogenous peptide, but m-DCs were functionally preferable to induce Th1 responses in vitro. Another surprising finding was that, while presentation to T cells upon simultaneous loading of several peptides with highly varying affinities and competing for the same class I or II molecule was possible, in priming experiments peptide competition clearly inhibited T cell induction. Although peptides will obviously vary in their individual properties, our study clearly points to some important principles that should be taken into account.
Keywords: antigen presentation, human, peptide, T cells, vaccination
* These authors contributed equally to this study.
Transmitting editor: R. Steinman
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  X.-L. Huang, Z. Fan, L. Borowski, and C. R. Rinaldo Multiple T-Cell Responses to Human Immunodeficiency Virus Type 1 Are Enhanced by Dendritic Cells Clin. Vaccine Immunol., October 1, 2009; 16(10): 1504 - 1516. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. Lesimple, E.-M. Neidhard, V. Vignard, C. Lefeuvre, H. Adamski, N. Labarriere, A. Carsin, D. Monnier, B. Collet, G. Clapisson, et al. Immunologic and Clinical Effects of Injecting Mature Peptide-Loaded Dendritic Cells by Intralymphatic and Intranodal Routes in Metastatic Melanoma Patients Clin. Cancer Res., December 15, 2006; 12(24): 7380 - 7388. [Abstract] [Full Text] [PDF]
|
|