What have we learned about non-involved psoriatic skin from large-scale gene expression studies?

Under våren 2015 och hösten 2014 har en mängd trafikmätningar, fasadreduktionsmätningar och modellering gjorts av trafik och byggnader i Stockholms stad. Syftet med mätningarna har varit att undersöka trafikbullersituationen som har varit en del av många debatter senaste åren. Mätningarna och modelleringen har snabbt visat en bild av hur problem uppstår i bostäder på grund av lågfrekvent buller som skapas av långsamtgående trafik. Allteftersom arbetet fortskritt har det blivit tydligare att just lågfrekvent buller bör beaktas i större grad än vad det gör idag vid stadsplanering, projektering av, och besiktning av byggnader. Detta arbete presenterar och diskuterar problematik kring regelverk om trafikbuller i Stockholm där hastighetsbegränsning är maximalt 50 km/h. Problematiken är kopplad till det lågfrekventa buller som många utsätts för i sina hem och avsaknaden av riktlinjer som behandlar det. Genom att presentera och diskutera dagens byggnormer, riktvärden, krav och skrivelser som behandlar trafikbuller samt ställa dessa mot mätdata och modellering av typfasader som uppförts senaste århundradet ges en tydlig bild av problematiken som uppstår med lågfrekvent trafikbuller.A great number of traffic noise measurements, façade transmission loss measurements and modelling of buildings in Stockholm have been undergone in the spring of 2015 and late autumn of 2014. The main purpose of these has been to investigate the traffic noise situation which has been the subject of many [also ongoing] debates. The measurements together with the modelling have shown existing problems with low frequency noise present in dwellings due to slow moving traffic. As the investigation has proceeded it’s become evident that in particular low frequency noise should be emphasized and considered in the planning of cities and execution and surveying of buildings. This work presents and discusses issues related to governmental guidelines and rules regarding traffic noise in Stockholm where the speed limit does not exceed 50 km/h. The issue is connected to the low frequency noise that people experience in their dwelling and the lack of guidelines controlling it. By presenting and discussing current building standards, guidelines, governmental rules and literature regarding traffic noise control and by demonstrating the findings from the acquired data, the reader will understand the problems related to low frequency traffic noise

Propionibacterium acnes induces autophagy in keratinocytes: involvement of multiple mechanisms

Propionibacterium acnes is a dominant member of the cutaneous microbiota. Herein, we evaluate the effects of different P. acnes strains and propionic acid on autophagy in keratinocytes. Our results showed that P. acnes strain 889 altered the architecture of the mitochondrial network, elevated the levels of LC3B-II, Beclin-1 and phospho-AMPKalpha, stimulated autophagic flux, facilitated intracellular redistribution of LC3B, increased average number of autophagosomes per cell, and enhanced development of acidic vesicular organelles in the HPV-KER cell line. Propionic acid increased the level of phospho-AMPKalpha, enhanced lipidation of LC3B, stimulated autophagic flux, as well as facilitated translocation of LC3B into autophagosomes in HPV-KER cells. P. acnes strains 889, 6609 and heat-killed strain 889 also stimulated autophagosome formation in primary keratinocytes to varying degrees. These results indicate that cell wall components and secreted propionic acid metabolite of P. acnes evoke mitochondrial damage successively, thereby trigger AMPK-associated activation of autophagy, which in turn facilitates the removal of dysfunctional mitochondria and promotes survival of keratinocytes. Thus, we suggest that low-level colonization of hair follicles with non-invasive P. acnes strains, by triggering a local increase in autophagic activity, might exert a profound effect on several physiological processes responsible for the maintenance of skin tissue homeostasis

ABC transzporterek vizsgálata emberi őssejtekben és a sejt-differenciálódás során = Expression and function of ABC transporters in human stem cells and during cell differentiation

A projektben az ABC (ATP-Binding Cassette) transzporterek kifejeződését és funkcióját vizsgáltuk emberi őssejtekben, valamint követtük a normális és daganatos sejtdifferenciálódás során bekövetkező molekuláris szintű változásokat. Elsősorban a gyógyszerek hatásában, anyagcseréjében, az ellenük kifejeződő rezisztenciában szereplő transzportereket, valamint a sejtmembrán lipid-anyagcseréjében szerepet játszó ABC transzportereket vizsgáltuk. A projekt fontos része volt az emberi embrionális őssejtek speciális tenyésztési és differenciálási módszereinek adaptálása, továbbfejlesztése. Az ABC transzporterek vizsgálata során igazoltuk, hogy a humán embrionális őssejtekben az ABCG2 a legjelentősebb xenobiotikum transzporter, a korai sejtdifferenciálódás során az ABCG2 kifejeződése először emelkedik, majd jelentősen csökken. Megállapítottuk, hogy az ABCG2 mRNS használata különbözik a tumorsejtekben, a differenciálódott szöveti sejtekben, illetve a nem-differenciálódott őssejtekben. Új, transzpozon-alapú módszereket dolgoztunk ki az őssejtek stabil genetikai módosítására, fluoreszcens riporter fehérjék bevitelére. Az ABCG2 és az ABCA1 fehérjék címkézett változatainak kifejezése lehetővé tette a transzporterek sejten belüli lokalizációjának követését. Részletesen elemeztük az ABCG2 multidrog transzporter szerkezet-funkció összefüggéseit, szubsztrátokkal jelentkező kölcsönhatásait, alkalmazásokat fejlesztettünk ki a gyógyszerhatások vizsgálatára. | In this project we have studied the expression and function of ABC (ATP-Binding Cassette) transporters in human embryonic and tumor stem cells and followed the changes during normal and tumor cell differentiation at a molecular level. We have focused on the investigation of ABC transporters involved in drug metabolism, cancer multidrug resistance and cellular lipid metabolism. An important part of the project was to establish and further develop proper laboratory conditions and methodologies for culturing and differentiating human pluripotent stem cells. When studying human ABC transporters in human embryonic stem cells we demonstrated the major role of the ABCG2 protein. We found that the expression of this transporter first increases, then greatly decreases during early stem cell differentiation. The use of mRNA was found to be different in the tumor cells, differentiated cells, and pluripotent stem cells, respectively. We have developed new, transposon-based methods for the stable genetic modification of pluripotent stem cells and for the expression of fluorescent reporter proteins. By using tagged versions of the ABCG2 and ABCA1 proteins we could follow the intracellular localization of these transporters. We have studied in detail the structure-function relationships and substrate interactions of the ABCG2 transporter and developed new assays for studying drug interactions

504 UVB-induced expression of fast-responding genes is modulated by huCOP1 in keratinocytes

Ultraviolet (UV) B is the most prominent physical carcinogen in the environment leading to the development of various skin cancers. We have previously demonstrated that the human ortholog of the Arabidopsis thaliana constitutive photomorphogenesis 1 (COP1) protein, huCOP1, is expressed in keratinocytes in a UVB-regulated manner and is a negative regulator of p53 as a posttranslational modifier. However, it was not known whether huCOP1 plays a role in mediating the UVB-induced early transcriptional responses of human keratinocytes. To clarify this question we produced transgenic cell lines in which the expression of huCOP1 was stably silenced. Real-time RT-PCR array showed that the stable siRNA-mediated silencing of huCOP1 affects the UVB response of several genes within 2 h of irradiation, indicating that altered huCOP1 expression sensitizes the cells toward UVB. Pathway analysis identified a molecular network in which 13 of the 30 examined UVB-regulated genes were organized around three central proteins. Since the expression of the investigated genes was upregulated by UVB in the siCOP1 cell line, we hypothesize that huCOP1 is a repressor of the identified pathway. Several members of the network have been implicated previously in the pathogenesis of non-melanoma skin cancers; therefore, clarifying the role of huCOP1 in these skin diseases may have clinical relevance in the future

Psoriatic Resolved Skin Epidermal Keratinocytes Retain Disease-Residual Transcriptomic and Epigenomic Profiles

The disease-residual transcriptomic profile (DRTP) within psoriatic healed/resolved skin and epidermal tissue-resident memory T (TRM) cells have been proposed to be crucial for the recurrence of old lesions. However, it is unclear whether epidermal keratinocytes are involved in disease recurrence. There is increasing evidence regarding the importance of epigenetic mechanisms in the pathogenesis of psoriasis. Nonetheless, the epigenetic changes that contribute to the recurrence of psoriasis remain unknown. The aim of this study was to elucidate the role of keratinocytes in psoriasis relapse. The epigenetic marks 5-methylcytosine (5-mC) and 5-hydroxymethylcytosine (5-hmC) were visualized using immunofluorescence staining, and RNA sequencing was performed on paired never-lesional and resolved epidermal and dermal compartments of skin from psoriasis patients. We observed diminished 5-mC and 5-hmC amounts and decreased mRNA expression of the ten-eleven translocation (TET) 3 enzyme in the resolved epidermis. SAMHD1, C10orf99, and AKR1B10: the highly dysregulated genes in resolved epidermis are known to be associated with pathogenesis of psoriasis, and the DRTP was enriched in WNT, TNF, and mTOR signaling pathways. Our results suggest that epigenetic changes detected in epidermal keratinocytes of resolved skin may be responsible for the DRTP in the same regions. Thus, the DRTP of keratinocytes may contribute to site-specific local relapse

Ultraviolet B-dependent changes in the expression of fast-responding early genes is modulated by huCOP1 in keratinocytes

Ultraviolet (UV) B is the most prominent physical carcinogen in the environment leading to the development of various skin cancers. We have previously demonstrated that the human orthologue of the Arabidopsis thaliana constitutive photomorphogenesis (COP)1 protein, huCOP1, is expressed in keratinocytes in a UVB-regulated manner and is a negative regulator of p53 as a post-translational modifier. However, it was not known whether huCOP1 plays a role in mediating the UVB-induced early transcriptional responses of human keratinocytes. In this study we found that stable small-interfering (si) RNA-mediated silencing of huCOP1 affects the UVB response of several genes within 2 h of irradiation indicating that altered huCOP1 expression sensitizes the cells toward UVB. Pathway analysis identified a molecular network in which 13 out of the 30 examined UVB-regulated genes were organized around three central proteins. As the expression of the investigated genes was upregulated by UVB in the siCOP1 cell line, we hypothesize that huCOP1 is a repressor of the identified pathway. Several members of the network have been implicated previously in the pathogenesis of nonmelanoma skin cancers; therefore, clarifying the role of huCOP1 in these skin diseases may have clinical relevance in the future