High-Resolution Transcriptional Profiling of Chemical-Stimulated Dendritic Cells Identifies Immunogenic Contact Allergens, but Not Prohaptens

Abstract

Allergic contact dermatitis is a complex syndrome and knowledge about the in vitro detection of small-molecular-weight compounds, particularly prohaptens, is limited. Therefore, we investigated chemical-induced gene expression changes in human antigen-presenting cells upon stimulation with immunogenic contact allergens, prohaptens and irritants. Monocyte-derived dendritic cells (moDCs) and THP-1 cells were stimulated with the prohapten cinnamic alcohol (CAlc), the hapten cinnamic aldehyde (CAld), an irritant and an obligatory sensitizer in vitro. Whole-genome screening and consecutive PCR analysis of differential gene expression in moDCs stimulated with either CAld or the obligatory sensitizer revealed coregulation of 11 marker genes which were related to immunological reactions (IL-8, CD1e, CD200R1, PLA2G5, TNFRSF11A), oxidative or metabolic stress responses (AKR1C3, SLC7A11, GCLM) or other processes (DPYLS3, TFPI, TRIM16). In contrast, the prohapten CAlc and the irritant did not change marker gene expression. In THP-1 cells, CAld and the positive control elicited similar expression changes in only 4 of the previously identified genes (IL-8, TRIM16, CD200R1, GCLM). In conclusion, we provide important insights into the pathophysiological basis of allergic contact dermatitis, identify marker genes suitable for skin hazard assessment and demonstrate that contact-allergenic prohaptens escape in in vitro detection if their skin metabolism is not taken into account.

Myeloid human cell lines lack functional regulation of aryl hydrocarbon receptor-dependent phase I genes

“…Human primary dendritic cells as well as myeloid cell lines are used in in vitro approaches to predict skin sensitization (Basketter et al, 2008;Ott et al, 2010;Python et al, 2009), e.g., the Myeloid U937 Skin Sensitization Test (MUSST), which measures increase of CD86 expression (Ade et al, 2006;Python et al, 2007), the human Cell Line Activation Test (h-CLAT), which assesses increase of CD86 and combined CD54 expression (Sakaguchi et al, 2006), or the Genomic Allergen Rapid Detection (GARD), which is based on a signature of predictive genes differentially regulated in the MUTZ3 cell line when stimulated with sensitizing compared to non-sensitizing compounds (Johansson et al, 2013).…”

“…It is hypothesized that NQO1 induction occurs via AhR-dependent Nrf2 activation (Haarmann-Stemmann et al, 2012). Ott et al (2010) and Python et al (2009) have identified NQO1 as a marker gene up-regulated after stimulation of moDCs with cinnamic aldehyde by microarray analysis. NQO1 was modulated by most sensitizers after exposure of MUTZ-3 cells and PBMDCs (peripheral blood mononuclear-derived dendritic cells) with selected sensitizers for 24 h (Python et al, 2009).…”

“…Human cell lines including THP-1, MUTZ-3 and U937 should undergo similar alterations after activation, which indicate their potential to behave like a DC. In addition to primary DCs, these cell lines are used as an alternative tool to predict skin sensitization (Basketter et al, 2008;Ott et al, 2010;Python et al, 2009).…”

Dexpanthenol Modulates Gene Expression in Skin Wound Healing in vivo

“…The Ambion® WT Expression Kit (Ambion, Kaufungen, Germany) was used to generate purified sense-strand cDNA with incorporated dUTP according to the technical manual. Fragmentation and labeling was done using the Affymetrix Gene Chip WT Terminal Labeling kit (Affymetrix, Santa Clara, Calif., USA) according to the manufacturer’s recommendations [15]. Each sample was hybridized to a Gene Chip Human Exon 1.0 ST array for 16 h at 45°C.…”

Advanced tests for skin and respiratory sensitization assessment

“…Recent studies revealed that ABC transporters not only have a protective function related to their capacity to extrude toxic compounds but also have additional regulatory functions of these transport systems on immune cells (Ott et al, 2010). the multidrug resistance related proteins (MRP, gene name: AtP-binding cassette C transporters, ABCC) are a subfamily of ABC transporters and consist of at least seven members.…”