title: Proinflammatory Cytokines and CD40 Ligand Enhance Cross-Presentation and Cross-Priming Capability of Human Dendritic Cells Internalizing Apoptotic Cancer Cells.
abstract: SUMMARY: Human monocyte-derived dendritic cells (DC) can ingest apoptotic tumor cells (ATC) and present tumor-associated antigens (TAA) to T cells, leading to the generation of tumor-specific cytotoxic effector cells (Cancer Res 2000;60:3542-9). To further augment antitumor effector cell responses, attempts were made to modify antigen presentation and cross-priming of T cells by DC fed with ATC. Proinflammatory cytokines (PC), CD40 ligand (CD40L) and/or interferon-gamma (IFN-gamma) were found to markedly enhance the immunogenicity of TAA presented by DC. While PC upregulated expression of major histocompatibility complex class I/II and costimulatory molecules on the surface of DC, CD40L +/- IFN-gamma increased interleukin (IL)-12 and to a lesser extent, IL-15 production by DC. Additionally, lactacystin, a specific proteasome inhibitor, significantly abrogated the effects of IFN-gamma and, in part, also those of CD40L or PC. The ability of DC + ATC to cross-prime TAA-inexperienced ("naive") T cells was significantly enhanced by PC and CD40L or CD40L + IFN-gamma, but not by IFN-gamma alone. These results indicate that future vaccines for patients with cancer incorporating DC fed with ATC could be made more effective by the addition of proinflammatory cytokines or CD40L +/- IFN-gamma to improve the DC function.
authors.affiliation: University of Pittsburgh Cancer Institute, Department of Surgery and Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, U.S.A.
authors.forename: Thomas K.
authors.initials: TK
authors.lastname: Hoffmann
authors.forename: Norbert
authors.initials: N
authors.lastname: Meidenbauer
authors.forename: Jan
authors.initials: J
authors.lastname: Müller-Berghaus
authors.forename: Walter J.
authors.initials: WJ
authors.lastname: Storkus
authors.forename: Theresa L.
authors.initials: TL
authors.lastname: Whiteside