Abstract
Using serum-free conditions, human monocyte-derived dendritic cells (MoDCs) tend to mature insufficiently in a TH1-polarizing direction under approved and standardized clinical conditions. However, for the initiation of an efficient tumour antigen-specific cytotoxic T-cell response, the induction of a distinct TH1 response is favourable. Therefore, to improve TH1 polarisation, the influence of interferon-gamma (IFN-γ) on the maturation of MoDCs was investigated with clinical-grade cytokines or lipopolysaccharide (LPS) in serum-free medium focusing on the viability, phenotypic characteristics, cytokine profile and restimulating capacities. As in previous research, we confirmed that in respect of viability and phenotypic characteristics, cytokine cocktails consisting of tumour necrosis factor-alpha (TNF-α), interleukin (IL)-1β, IL-6 and prostaglandin (PG) E2, mature MoDCs most efficiently. However, these cytokine-matured MoDCs secreted relatively high levels of IL-10 and only low levels of IL-12p70. Remarkably, if IFN-γ was added, significantly lower levels of IL-10 concomitant with higher levels of IL-12p70 could be detected. Pretreatment with IFN-γ did not improve the phenotypic characteristics nor the TH1 polarisation of MoDCs. Nevertheless, MoDCs matured with clinical-grade cytokines and IFN-γ could be re-stimulated most effectively with IFN-γ. In conclusion, our work demonstrates that addition of INF-γ to clinical-grade cytokine cocktails readily matures MoDCs and enhances their TH1 polarisation efficiently under serum-free conditions.
Footnotes
-
↵* Both authors contributed equally to this work.
-
Abbrevations: CCR, chemokine receptor; CD, cluster of differentiation; CTL, cytotoxic T lymphocytes; DCs, dendritic cells; moDCs, monocyte-derived dendritic cells; DC1, TH1 polarised dendritic cells; ELISPOT, enzyme-linked immunosorbent spot; FITC: fluorescein-5-isothiocyanat; GM-CSF, granulocyte-macrophage colony stimulating factor; HLA, human leucocyte antigen; INF-γ, interferon-gamma; IL, interleukin; LPS, lipopolysaccharide; MHC, major histocompatibility complex; PBMC, peripheral blood mononuclear cells; PBS, phosphate-buffered saline; PE, phycoerythrin; PGE2, prostaglandin E2; TH-response, T-helper cell response; TLR, toll-like receptors; TNF, tumour necrosis factor.
- Received November 21, 2007.
- Revision received January 9, 2008.
- Accepted February 4, 2008.
- Copyright© 2008 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved