Project description:Keratin 1 (KRT1) and its heterodimer partner keratin 10 (KRT10) constitute the intermediate filament cytoskeleton of suprabasal skin keratinocytes. They participate in formation of the epidermal barrier, which protects against dehydration and inflammation. Mutations in KRT1 cause keratinopathic ichthyosis with erythema, recurrent inflammation, and barrier defects. Here, we show that genetic deletion of Krt1 in mice causes a defective inside-out epidermal barrier, pre- and postnatal increases in Mrp8/Mrp14, interleukin (IL) 18, IL-33, and thymic stromal lymphopoietin (TSLP) in skin extracts, and systemic release of IL-18 into newborn serum. Perinatal lethality was partially rescued by treatment with glucocorticoids to promote barrier repair or with IL- 18-blocking antibodies in utero. In human keratinocytes, IL-18 release was cellautonomous and caspase-1-dependent, indicating KRT1-dependent inflammasome activation. Our data reveal a novl function of KRT1 in controlling inflammasome activity and stimulating barrier formation, thereby integrating the keratin cytoskeleton into the epidermal immune response. In view of their widespread expression, keratins merit investigation of their functions in inflammatory conditions, including asthma and inflammatory bowel disorders. Total RNA was obtained from epidermis or full-thickness skin of Krt1+/+ and Krt1-/- mice (C57BL/6 background) at P0 (newborn).
Project description:Palaeoproteomic study of mummified human skin using a non-destructive sampling technique, based on mixed-bed chromatographic media stabilised on ethylene vinyl acetate membranes (“EVA”), which had previously been used exclusively on historical material, was successful in extracting ancient proteins from the surface of Ancient Egyptian mummies. We tested the method on a decontextualised fragment of skin and assessed the endogeneity of its metaproteome by comparison with a procedural blank. Furthermore, we retrieved and authenticated sequences of collagen and keratin from the mummy of a young woman (Supp. 16747 of the Museum of Anthropology and Ethnography of the University of Turin) who lived and died between 2400 and 2200 BC, during the Old Kingdom of Egypt.
Project description:Keratin 1 (KRT1) and its heterodimer partner keratin 10 (KRT10) constitute the intermediate filament cytoskeleton of suprabasal skin keratinocytes. They participate in formation of the epidermal barrier, which protects against dehydration and inflammation. Mutations in KRT1 cause keratinopathic ichthyosis with erythema, recurrent inflammation, and barrier defects. Here, we show that genetic deletion of Krt1 in mice causes a defective inside-out epidermal barrier, pre- and postnatal increases in Mrp8/Mrp14, interleukin (IL) 18, IL-33, and thymic stromal lymphopoietin (TSLP) in skin extracts, and systemic release of IL-18 into newborn serum. Perinatal lethality was partially rescued by treatment with glucocorticoids to promote barrier repair or with IL- 18-blocking antibodies in utero. In human keratinocytes, IL-18 release was cellautonomous and caspase-1-dependent, indicating KRT1-dependent inflammasome activation. Our data reveal a novl function of KRT1 in controlling inflammasome activity and stimulating barrier formation, thereby integrating the keratin cytoskeleton into the epidermal immune response. In view of their widespread expression, keratins merit investigation of their functions in inflammatory conditions, including asthma and inflammatory bowel disorders.
Project description:Dermal fibroblasts were isolated from healthy human skin or chronic psoriatic plaques for cultivation, which were subsequently subjected to RNA-Seq.
Project description:Dermal lymphatic endothelial cells were isolated from chronic psoriatic plaques or healthy human skin for cultivation and subsequently subjected to RNA-Seq.
Project description:Skin homeostasis is guided by spatiotemporal regulation of gene expression, establishing each stage of keratinocyte differentiation. The current study presents transcriptomic and chromatin profiling for the proliferating (basal) and differentiated (suprabasal) cell populations derived from neonate mice (p0-p2) skin epidermis. This multi-omic approach will enable idenitification of cell specific epidermal cross-talk central to the equlibirum.
Project description:Our growing awareness of the microbial world's importance and diversity contrasts starkly with our limited understanding of its fundamental structure. Despite recent advances in DNA sequencing, a lack of standardized protocols and common analytical frameworks impedes comparisons among studies, hindering the development of global inferences about microbial life on Earth. Here we present a meta-analysis of microbial community samples collected by hundreds of researchers for the Earth Microbiome Project. Coordinated protocols and new analytical methods, particularly the use of exact sequences instead of clustered operational taxonomic units, enable bacterial and archaeal ribosomal RNA gene sequences to be followed across multiple studies and allow us to explore patterns of diversity at an unprecedented scale. The result is both a reference database giving global context to DNA sequence data and a framework for incorporating data from future studies, fostering increasingly complete characterization of Earth's microbial diversity.
Project description:We generated KA mutant mice (Krt14-CreERT + ABCA12-flox/flox) and controls (ABCA12-flox/flox) that enabled us to assess the effects of deleting a critical barrier gene, ABCA12, in the skin epidermis following tamoxifen treatment. These studies identified numerous differentially expressed genes (DEGs) upon barrier disruption/ABCA12 deletion, including compensatory upregulation of genes involved with epidermal differentiation and barrier function. Overall, this data-set provides a global view of molecular changes that occur in adult mouse skin following barrier perturbation.
Project description:The skin`s microbiome is predominantly commensalic, harbouring a metabolic potential far exceeding that of its host. While toxicologically relevant there is still a lack of suitable models. We now report on a new biologically characterised co-culture that allows studying microbe-host interactions for extended periods of time in situ . The system is based on a commercially available 3D skin model. In a proof of concept this model was colonised with single and mixed cultures of two selected skin commensals. Two different methods were used to quantify the bacteria on the surface of the skin models. While M. luteus established a stable co-culture, P. oleovorans maintained slow continuous growth over the 8 day cultivation period. A detailed skin transcriptome analysis showed bacterial colonisation leading to up to 3318 significant changes. Additionally FACS, ELISA and Western blot analyses were carried out to analyse secretion of cytokines and growth factors. Changes found in colonised skin were varied dependent on the bacterial species used and comprised immunomodulatory functions, such as secretion of IL-1α/β, Il-6, antimicrobial peptides and increased gene transcription of IL-10 and TLR2. The colonisation also influenced the secretion of many grows factors as VFGFA and FGF2. Notably, many of these changes have already previously been associated with the presence of skin commensals. Concomitantly the model gained first insights on the microbiome’s influence on skin xenobiotic metabolism (i.e., CYP1A1, CYP1B1 and CYP2D6) and olfactory receptor expression. The system provides urgently needed experimental access for assessing the toxicological impact of the microbiome’s xenobiotic metabolism in situ.