Gene Expression Profile Comparison of Human Epidermal Keratinocyte Cell Culture Models Following Sulfur Mustard Exposure

Normal human epidermal keratinocytes (NHEKs) and HaCaTs have been widely used as cell culture models to study the effects of cutaneous sulfur mustard (HD) exposure. While these cell lines are similar, one key difference is that NHEKs are primary cells, whereas HaCaT cells are a transformed line with a mutation in the p53 gene. However, the impact of this mutation on the response of HaCaT cells to HD is unclear. Thus, gene expression profiling was performed to compare the transcriptional responses of NHEKs and HaCaTs after HD exposure. Cells were exposed to 0, 25, and 200 µM HD, harvested at 1 h and 8 h post-exposure, and processed for microarray analysis. Principal component analysis of the microarray data suggested profile differences based on cell type, but both cell types respond similarly to HD with regard to dose and time. To further analyze the expression profiles at various doses, the dataset was filtered by dose, and an analysis of variance was performed using cell type as the factor; the pathways most significantly different between these cell types were identified. At all three doses, the p53 and N-glycan degradation pathways were significantly different between NHEKs and HaCaTs. Interestingly, p53 responsive genes showed differences and similarities across cell types, which may provide insight into the role of p53 in HD toxicity. The inflammatory pathways expected to respond to HD exposure were not significantly different between cell types, suggesting that both NHEKs and HaCaTs are appropriate models to study the inflammatory effects of HD. Cells were exposed to 0 µM, 25 µM, or 200 µM sulfur mustard and collected at 1 h or 8 h post exposure. Time matched controls were included for each group. Three replicates (n=3) were collected for each experimental group.