Project description:We analysed the whole-genome transcriptional profile of 6 cell lines of dark melanocytes (DM) and 6 of light melanocytes (LM) at basal conditions and after UVB at different time points (6, 12 and 24h) to investigate the mechanisms by which melanocytes protect human skin from the damaging effects of ultraviolet-B radiation (UVB). Further, we assessed the effect of different keratinocyte-conditioned media (KCM+ and KCM-) on melanocytes. We analysed six lines of melanocytes isolated from lightly pigmented neonatal foreskin (LM), and six lines from darkly pigmented neonatal foreskin (DM), at 0, 6, 12 and 24 hours post UV irradiation. We also assessed the effect of different keratinocyte-conditioned media (KCM+ or KCM-)
Project description:Gene expression profiling of immortalized human mesenchymal stem cells with hTERT/E6/E7 transfected MSCs. hTERT may change gene expression in MSCs. Goal was to determine the gene expressions of immortalized MSCs.
Project description:Transcriptional profiling of human mesenchymal stem cells comparing normoxic MSCs cells with hypoxic MSCs cells. Hypoxia may inhibit senescence of MSCs during expansion. Goal was to determine the effects of hypoxia on global MSCs gene expression.
Project description:Ultraviolet (UV) radiation is a major melanoma risk factor, yet underlying mechanisms remain poorly understood. Here we introduce a mouse model permitting fluorescence-aided melanocyte imaging and isolation following in vivo UV irradiation. We use expression profiling to show that activated neonatal skin melanocytes isolated following a melanomagenic UVB dose bear a distinct, persistent interferon-response signature, including genes associated with immunoevasion. UVB-induced melanocyte activation, characterized by aberrant growth and migration, was abolished by antibody-mediated systemic blockade of interferon-gamma (IFN-gamma), but not type-I interferons. IFN-gamma was produced by macrophages recruited to neonatal skin by UVB-induced chemokine receptor Ccr2 ligands. Admixed recruited skin macrophages enhanced transplanted melanoma growth by inhibiting apoptosis; notably, IFN-gamma blockade abolished macrophage-associated melanoma growth and survival. IFN-gamma-producing macrophages were identified in 70% of human melanomas examined. Our data reveal an unanticipated role for IFN-gamma in promoting melanocytic cell survival/immunoevasion, and suggest IFN-gamma-R signaling represents a novel therapeutic melanoma target. Biologic replicates of UVA- and UVB-treated mouse melanocytes, as well as untreated mouse melanocytes and mouse keratinocytes, were used to define melanocyte expression signatures associated with UV treatment.
Project description:Gene methylation profiling of immortalized human mesenchymal stem cells comparing HPV E6/E7-transfected MSCs cells with human telomerase reverse transcriptase (hTERT)- and HPV E6/E7-transfected MSCs. hTERT may increase gene methylation in MSCs. Goal was to determine the effects of different transfected genes on global gene methylation in MSCs.
Project description:UV-induced CPDs were mapped in primary skin melanocytes or normal human skin fibroblasts following either UVC or UVB irradiation and in isolated human genomic DNA (naked DNA control) that was UVB or UVC irradiated. CPDs were mapped across the human genome using the CPD-capture-seq method and the resulting libraries were captured for ~4000 genomic regions of interest (~3 Mbp) of the human genome by the company Rapid Genomics prior to Illumina sequencing