Dendritic Cell mediated immune responses are shaped by Interleukin-15 and Interleukin -21

The immune system contains a distinct group of antigen presenting cells, called dendritic cells (DCs), that are specialized to capture antigens and initiate T cell immunity. The complex processes involved are critically balanced by soluble factors, such as cytokines, produced by DCs itself or released by neighboring cells. The goal of this study was to examine how differentiation, maturation and function of DCs are modulated by two particular cytokines, namely IL-15 and IL-21, which possess regulatory activities on immune responses. Here it is shown that IL-15 has stimulatory effects on DC activation and on T cell priming. Thus IL-15 evoke highly mature DCs whereas in contrast IL-21 mediates inhibitory effects resulting in phenotypic and functional immature DCs with decreased T cell stimulatory capacities in vitro and in vivo.To understand by which means DC activation is modulated by IL-15 and consequently which T cell subsets are influenced by this cytokine, several in vivo models were investigated. On the one hand we used genetic deficient mice for IL-15 (IL-15-/-) and its high affinity receptor (IL-15Ra-/-) and on the other hand we treated wild type mice with an IL-15 antagonist, a soluble IL-15Ra, to block the activity of the cytokine without affecting DC differentiation. The studies revealed that IL-15 and IL-21, modulate DC function. DC-derived IL-15 is essential for the initiation of Th1 type immune responses. Despite sharing a common receptor subunit, IL-15 and IL-21 exhibit completely opposite effects on DC biology. The dichotomous effects of IL-15 and IL-21 on DC mediated T cell activation shed new light on the understanding of immune modulatory mechanisms. Thus, the application of agonists or antagonists of these cytokines can be conceived as therapeutical tools to control immune response

Christina Rossetti's "Goblin market" : Milton revised or revived?

The present study examines Christina Rossetti's (1830-94) best-known poem "Goblin Market" (1859) as a response to John Milton's (1608-74) Paradise Lost (1667) and Paradise Regained (1674). Rossetti's poem relates to Milton's twin epics with a surprising degree of complexity, something that the thesis demonstrates through a large number of hitherto unexplored textual parallels. In its recontextualisation of Rossetti's poetry, this study balances interpretative strategies evolved by feminism with more historicist readings. SinceGilbert and Gubar's landmark feminist work of 1979, it has become something of a critical commonplace that Milton was a figure of patriarchal oppression whom women writers have challenged through revision. As a consequence, intertextual Rossetti studies have tended to emphasise such a revisionist element in her achievement. But if we place "Goblin Market" within the larger context of Rossetti's thoughts on religion and poetry throughout her writing, and if we de-emphasise the dichotomy between Rossetti and her male precursor, alternative patterns of reading begin to emerge. This thesis argues that Rossetti's aim was not only to revise Milton but also to revive him. It develops this point in several ways: first, by introducing the subject and theoretically arguing that literary allusiveness is not necessarily a matter of oedipal or feminist envy only (Chapter One); second, by determining the nature and extent of Rossetti's Miltonic allusions in terms of theme, imagery and language (Chapter Two);and third, by examining their function in terms of argument (Chapters Three andFour). I n an age of increasing religious doubt, Rossetti's poetry provided a subtle challenge not so much to Milton as to the emerging scepticism and aestheticism in Victorian society and its art-world, and not least to the secular tendencies of the second generation of Pre-Raphaelites, including Dante Gabriel Rossetti. Christina Rossetti was ahead of her time (and perhaps ours) in seeing the feminist potential in both John Milton and the Christian message. In the soul's relation to Christ, gender does not matter. What matters is the individual's quest for salvation, a quest in which poetry is a sacramental act, with a transformative, unifying function. Rossetti's poems both depict and constitute such a quest for union with God, on the assumption that God's word offers a pathway that is open to men as well as women

Ice-fuelled food webs in the Polar Oceans

The Arctic Ocean is undergoing substantial warming and sea ice loss which are likely to cause changes in primary production, export fluxes and productivity of the Arctic marine ecosystems. Yet, we lack sufficient information about the ecosystem productivity, organic carbon cycling and cryo-pelago-benthic coupling processes in the Arctic Ocean. Particularly such information is scarce for deep Arctic basins and the spring to summer transition time. Our aim was to provide carbon budget estimations under different regimes and bloom development stages in the region north of Svalbard. We conducted ecological and biogeochemical early spring process studies in sea ice covered areas, from the shelf to the basins of the European Arctic margin and on the Yermak Plateau during the TRANSSIZ cruise PS 92 on the ice breaker R/V Polarstern in May/June 2015. We identified the potential characteristics of carbon production of primary producers in the sea ice and water column, and secondary production of zooplankton and benthos. We looked into the organic carbon production fate and export, including respiration and burial, as well as identified similarities and differences in ecosystem functioning along topography- , sea ice- and water mass-related gradients. This scientific initiative was undertaken by Arctic in Rapid Transition (ART) International Arctic Science Committee (IASC) network

On the reproducibility of extrusion-based bioprinting: round robin study on standardization in the field

The outcome of three-dimensional (3D) bioprinting heavily depends, amongst others, on the interaction between the developed bioink, the printing process, and the printing equipment. However, if this interplay is ensured, bioprinting promises unmatched possibilities in the health care area. To pave the way for comparing newly developed biomaterials, clinical studies, and medical applications (i.e. printed organs, patient-specific tissues), there is a great need for standardization of manufacturing methods in order to enable technology transfers. Despite the importance of such standardization, there is currently a tremendous lack of empirical data that examines the reproducibility and robustness of production in more than one location at a time. In this work, we present data derived from a round robin test for extrusion-based 3D printing performance comprising 12 different academic laboratories throughout Germany and analyze the respective prints using automated image analysis (IA) in three independent academic groups. The fabrication of objects from polymer solutions was standardized as much as currently possible to allow studying the comparability of results from different laboratories. This study has led to the conclusion that current standardization conditions still leave room for the intervention of operators due to missing automation of the equipment. This affects significantly the reproducibility and comparability of bioprinting experiments in multiple laboratories. Nevertheless, automated IA proved to be a suitable methodology for quality assurance as three independently developed workflows achieved similar results. Moreover, the extracted data describing geometric features showed how the function of printers affects the quality of the printed object. A significant step toward standardization of the process was made as an infrastructure for distribution of material and methods, as well as for data transfer and storage was successfully established

On the reproducibility of extrusion-based bioprinting: round robin study on standardization in the field

The outcome of three-dimensional (3D) bioprinting heavily depends, amongst others, on the interaction between the developed bioink, the printing process, and the printing equipment. However, if this interplay is ensured, bioprinting promises unmatched possibilities in the health care area. To pave the way for comparing newly developed biomaterials, clinical studies, and medical applications (i.e. printed organs, patient-specific tissues), there is a great need for standardization of manufacturing methods in order to enable technology transfers. Despite the importance of such standardization, there is currently a tremendous lack of empirical data that examines the reproducibility and robustness of production in more than one location at a time. In this work, we present data derived from a round robin test for extrusion-based 3D printing performance comprising 12 different academic laboratories throughout Germany and analyze the respective prints using automated image analysis (IA) in three independent academic groups. The fabrication of objects from polymer solutions was standardized as much as currently possible to allow studying the comparability of results from different laboratories. This study has led to the conclusion that current standardization conditions still leave room for the intervention of operators due to missing automation of the equipment. This affects significantly the reproducibility and comparability of bioprinting experiments in multiple laboratories. Nevertheless, automated IA proved to be a suitable methodology for quality assurance as three independently developed workflows achieved similar results. Moreover, the extracted data describing geometric features showed how the function of printers affects the quality of the printed object. A significant step toward standardization of the process was made as an infrastructure for distribution of material and methods, as well as for data transfer and storage was successfully established

Developing priority variables ("ecosystem Essential Ocean Variables" — eEOVs) for observing dynamics and change in Southern Ocean ecosystems

Reliable statements about variability and change in marine ecosystems and their underlying causes are needed to report on their status and to guide management. Here we use the Framework on Ocean Observing (FOO) to begin developing ecosystem Essential Ocean Variables (eEOVs) for the Southern Ocean Observing System (SOOS). An eEOV is a defined biological or ecological quantity, which is derived from field observations, and which contributes significantly to assessments of Southern Ocean ecosystems. Here, assessments are concerned with estimating status and trends in ecosystem properties, attribution of trends to causes, and predicting future trajectories. eEOVs should be feasible to collect at appropriate spatial and temporal scales and are useful to the extent that they contribute to direct estimation of trends and/or attribution, and/or development of ecological (statistical or simulation) models to support assessments. In this paper we outline the rationale, including establishing a set of criteria, for selecting eEOVs for the SOOS and develop a list of candidate eEOVs for further evaluation. Other than habitat variables, nine types of eEOVs for Southern Ocean taxa are identified within three classes: state (magnitude, genetic/species, size spectrum), predator–prey (diet, foraging range), and autecology (phenology, reproductive rate, individual growth rate, detritus). Most candidates for the suite of Southern Ocean taxa relate to state or diet. Candidate autecological eEOVs have not been developed other than for marine mammals and birds. We consider some of the spatial and temporal issues that will influence the adoption and use of eEOVs in an observing system in the Southern Ocean, noting that existing operations and platforms potentially provide coverage of the four main sectors of the region — the East and West Pacific, Atlantic and Indian. Lastly, we discuss the importance of simulation modelling in helping with the design of the observing system in the long term. Regional boundary: south of 30°S

Toward a reliable assessment of potential ecological impacts of deep‐sea polymetallic nodule mining on abyssal infauna

peer reviewedThe increasing demand for metals is pushing forward the progress of deep-sea mining industry. The abyss between the Clarion and Clipperton Fracture Zones (CCFZ), a region holding a higher concentration of minerals than land deposits, is the most targeted area for the exploration of polymetallic nodules worldwide, which may likely disturb the seafloor across large areas and over many years. Effects from nodule extraction cause acute biodiversity loss of organisms inhabiting sediments and polymetallic nodules. Attention to deep-sea ecosystems and their services has to be considered before mining starts but the lack of basic scientific knowledge on the methodologies for the ecological surveys of fauna in the context of deep-sea mining impacts is still scarce. We review the methodology to sample, process and investigate metazoan infauna both inhabiting sediments and nodules dwelling on these polymetallic-nodule areas. We suggest effective procedures for sampling designs, devices and methods involving gear types, sediment processing, morphological and genetic identification including metabarcoding and proteomic fingerprinting, the assessment of biomass, functional traits, fatty acids, and stable isotope studies within the CCFZ based on both first-hand experiences and literature. We recommend multi- and boxcorers for the quantitative assessments of meio- and macrofauna, respectively. The assessment of biodiversity at species level should be focused and/or the combination of morphological with metabarcoding or proteomic fingerprinting techniques. We highlight that biomass, functional traits, and trophic markers may provide critical insights for biodiversity assessments and how statistical modeling facilitates predicting patterns spatially across point-source data and is essential for conservation management

Use of Cis-[18F]Fluoro-Proline for Assessment of Exercise-Related Collagen Synthesis in Musculoskeletal Connective Tissue

Protein turnover in collagen rich tissue is influenced by exercise, but can only with difficulty be studied in vivo due to use of invasive procedure. The present study was done to investigate the possibility of applying the PET-tracer, cis-[18F]fluoro-proline (cis-Fpro), for non-invasive assessment of collagen synthesis in rat musculoskeletal tissues at rest and following short-term (3 days) treadmill running. Musculoskeletal collagen synthesis was studied in rats at rest and 24 h post-exercise. At each session, rats were PET scanned at two time points following injection of cis-FPro: (60 and 240 min p.i). SUV were calculated for Achilles tendon, calf muscle and tibial bone. The PET-derived results were compared to mRNA expression of collagen type I and III. Tibial bone had the highest SUV that increased significantly (p<0.001) from the early (60 min) to the late (240 min) PET scan, while SUV in tendon and muscle decreased (p<0.001). Exercise had no influence on SUV, which was contradicted by an increased gene expression of collagen type I and III in muscle and tendon. The clearly, visible uptake of cis-Fpro in the collagen-rich musculoskeletal tissues is promising for multi-tissue studies in vivo. The tissue-specific differences with the highest basal uptake in bone are in accordance with earlier studies relying on tissue incorporation of isotopic-labelled proline. A possible explanation of the failure to demonstrate enhanced collagen synthesis following exercise, despite augmented collagen type I and III transcription, is that SUV calculations are not sensitive enough to detect minor changes in collagen synthesis. Further studies including kinetic compartment modeling must be performed to establish whether cis-Fpro can be used for non-invasive in-vivo assessment of exercise-induced changes in musculoskeletal collagen synthesis