Group 2 innate lymphoid cells (ILC2s) release interleukin-13 (IL-13) during protective immunity to helminth infection and detrimentally during allergy and asthma. Using two mouse models to deplete ...ILC2s in vivo, we demonstrate that T helper 2 (Th2) cell responses are impaired in the absence of ILC2s. We show that MHCII-expressing ILC2s interact with antigen-specific T cells to instigate a dialog in which IL-2 production from T cells promotes ILC2 proliferation and IL-13 production. Deletion of MHCII renders IL-13-expressing ILC2s incapable of efficiently inducing Nippostrongylus brasiliensis expulsion. Thus, during transition to adaptive T cell-mediated immunity, the ILC2 and T cell crosstalk contributes to their mutual maintenance, expansion and cytokine production. This interaction appears to augment dendritic-cell-induced T cell activation and identifies a previously unappreciated pathway in the regulation of type-2 immunity.
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•Genetic ablation of ILC2s impairs type-2 immunity•MHCII-expressing ILC2s potentiate Th2 responses•IL-2 from T cells promotes ILC2 proliferation and expression of type-2 cytokines•MHCII and IL-13 expression by ILC2s is important for N. brasiliensis expulsion
Type-2 innate lymphoid cells proliferate and release interleukin-13 during protective immunity to helminth infection and detrimentally during allergy and asthma. McKenzie and colleagues establish that these activities are potentiated through an MHC class II-mediated dialogue with T cells.
Type 2 innate lymphoid cells (ILC2s, nuocytes, NHC) require RORA and GATA3 for their development. We show that human ILC2s express skin homing receptors and infiltrate the skin after allergen ...challenge, where they produce the type 2 cytokines IL-5 and IL-13. Skin-derived ILC2s express the IL-33 receptor ST2, which is up-regulated during activation, and are enriched in lesional skin biopsies from atopic patients. Signaling via IL-33 induces type 2 cytokine and amphiregulin expression, and increases ILC2 migration. Furthermore, we demonstrate that E-cadherin ligation on human ILC2 dramatically inhibits IL-5 and IL-13 production. Interestingly, down-regulation of E-cadherin is characteristic of filaggrin insufficiency, a cardinal feature of atopic dermatitis (AD). ILC2 may contribute to increases in type 2 cytokine production in the absence of the suppressive E-cadherin ligation through this novel mechanism of barrier sensing. Using Rag1(-/-) and RORα-deficient mice, we confirm that ILC2s are present in mouse skin and promote AD-like inflammation. IL-25 and IL-33 are the predominant ILC2-inducing cytokines in this model. The presence of ILC2s in skin, and their production of type 2 cytokines in response to IL-33, identifies a role for ILC2s in the pathogenesis of cutaneous atopic disease.
This paper presents the results of validation of an open source Direct Simulation Monte Carlo (DSMC) code for general application to rarefied gas flows. The new DSMC code, called
dsmcFoam, has been ...written within the framework of the open source C++ CFD toolbox OpenFOAM. The main features of
dsmcFoam code include the capability to perform both steady and transient solutions, to model arbitrary 2D/3D geometries, and unlimited parallel processing. Test cases have been selected to cover a wide range of benchmark examples from 1D to 3D. These include relaxation to equilibrium, 2D flow over a flat plate and a cylinder, and 3D supersonic flows over complex geometries. In all cases,
dsmcFoam shows very good agreement with data provided by both analytical solutions and other contemporary DSMC codes.
These essays in political philosophy by T. M. Scanlon, written between 1969 and 1999, examine the standards by which social and political institutions should be justified and appraised. Scanlon ...explains how the powers of just institutions are limited by rights such as freedom of expression, and considers why these limits should be respected even when it seems that better results could be achieved by violating them. Other topics which are explored include voluntariness and consent, freedom of expression, tolerance, punishment, and human rights. The collection includes the classic essays 'Preference and Urgency', 'A Theory of Freedom of Expression', and 'Contractualism and Utilitarianism', as well as a number of other essays that have hitherto not been easily accessible. It will be essential reading for all those studying these topics from the perspective of political philosophy, politics, and law.
The Dilleniaceae is known to produce nectarless flowers pollinated by bees, but the fact that bats ingest Dillenia biflora pollen led us to question pollination assumptions for these trees. We aimed ...to identify the pollinators of D. biflora, check for nectar presence, and investigate potential for cleistogamy and global prevalence of this pollination system. We examined aspects of the pollination of D. biflora on two Fijian islands using video recordings, direct observations, hand pollination, measurements (flowers, bite marks, nectar), and monitoring. The flowers, receptive for one night, contained copious nectar and had permanently closed globose corollas that required removal by bats for pollination. All the 101 flowers that retained their corolla died and did not produce seeds by cleistogamy. The bat Notopteris macdonaldi was well adapted to corolla removal. Keeping corollas closed until bats manipulate the nectar-rich flowers is a beneficial strategy in high-rainfall environments with many flower parasites. We propose to name a pollination system reliant exclusively on bats "chiropteropisteusis." From clues in the literature, other species in the geographical range of Dillenia are probably chiropteropisunous. Chiropteropisteusis should be investigated in the Old-World range of Dillenia, many species of which are threatened. The remarkable "fall" of the entire corolla observed by an earlier botanist for several species in the genus is most likely attributable to bats. This discovery has important implications for the conservation of bat-dependent trees and their associated fauna, particularly considering the high level of threat faced by flying-foxes globally.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This paper presents a community effort to develop good practice guidelines for the validation of global coarse-scale satellite soil moisture products. We provide theoretical background, a review of ...state-of-the-art methodologies for estimating errors in soil moisture data sets, practical recommendations on data pre-processing and presentation of statistical results, and a recommended validation protocol that is supplemented with an example validation exercise focused on microwave-based surface soil moisture products. We conclude by identifying research gaps that should be addressed in the near future.
•Satellite soil moisture validation methods are reviewed•Community-agreed validation good practice guidelines are presented•A standardized satellite soil moisture validation protocol is provided
Bat pollination of Dillenia in Fiji, a genus that was presumed to be pollinated by bees, posits that other Dillenia species may be bat‐pollinated, with implications for conservation and the ...understanding of angiosperm evolution. Botanical descriptions of some corolla behaviours (‘falling as a whole’) suggest bat removal of permanently closed corollas, as in D. biflora. Considering the remoteness of species of interest, we reviewed some Dillenia floral traits to hypothesise what they may mean for bat pollination of the genus. We investigated D. biflora pollen grains apertures and reviewed Dillenia literature concerning corolla behaviour and colour, and pollen apertures and presentation, including pores and staminodes. Our samples had dramatically different ratios of tricolpate to tetracolpate pollen grains, a trait that does not exclude pollination by bees. Petal colour polymorphism occurs, with mixed colours proportionately less common in flowers with corollas that open. The proportion of species with staminodes did not differ between those presumed to be pollinated by bats and others, but anthers of the former were significantly more likely to have apical pores, and stamens all had similar length or were slightly longer in the middle, whereas stamens in two distinct groups occurred in 55% of bee‐pollinated species. Pollen heteromorphy may facilitate pollination by different taxa in tropical environments. However, anther apical pores and stamen uniformity are more likely to be associated with bat‐pollinated species than are other morphologies. Dillenia could be a useful model to examine evolutionary aspects of colour, heteranthery, staminodes and pollen heteromorphy. Only field work will verify bat pollination and the implications of bat dependence for Dillenia species.
Dillenia species, like all members of the phylogenetically mysterious family Dilleniaceae, were believed to be nectarless and pollinated by bees until the discovery that D. biflora was pollinated by bats in Fiji. Uniform stamens and apical anther pores, dominant traits in species suspected to be pollinated by bats because their corollas do not open, add evidence that several Dillenia species, including threatened ones, may need bats for pollination.
Innate-like NKT cells conspicuously accumulate within the liver microvasculature of healthy mice, crawling on the luminal side of endothelial cells, but their general recirculation pattern and the ...mechanism of their intravascular behavior have not been elucidated. Using parabiotic mice, we demonstrated that, despite their intravascular location, most liver NKT cells failed to recirculate. Antibody blocking experiments established that they were retained locally through constitutive LFA-1-intercellular adhesion molecule (ICAM) 1 interactions. This unprecedented lifelong intravascular residence could be induced in conventional CD4 T cells by the sole expression of promyelocytic leukemia zinc finger (PLZF), a transcription factor specifically expressed in the NKT lineage. These findings reveal the unique genetic and biochemical pathway that underlies the innate intravascular surveillance program of NKT cells.
Forms of Hypothetical Justification Scanlon, T. M.
Journal of human development and capabilities,
04/2019, Letnik:
20, Številka:
2
Journal Article
Recenzirano
A critical discussion of the appeal, in various contexts, of ideas of hypothetical agreement, with particular reference to Amartya Sen's criticism of John Rawls' Original Position argument, and to ...Sen's ideas of "membership entitlement" and "enlightenment relevance."
The differentiation of several T- and B-cell effector programs in the immune system is directed by signature transcription factors that induce rapid epigenetic remodelling. Here we report that ...promyelocytic leukaemia zinc finger (PLZF), the BTB-zinc finger (BTB-ZF) transcription factor directing the innate-like effector program of natural killer T-cell thymocytes, is prominently associated with cullin 3 (CUL3), an E3 ubiquitin ligase previously shown to use BTB domain-containing proteins as adaptors for substrate binding. PLZF transports CUL3 to the nucleus, where the two proteins are associated within a chromatin-modifying complex. Furthermore, PLZF expression results in selective ubiquitination changes of several components of this complex. CUL3 was also found associated with the BTB-ZF transcription factor BCL6, which directs the germinal-centre B cell and follicular T-helper cell programs. Conditional CUL3 deletion in mice demonstrated an essential role for CUL3 in the development of PLZF- and BCL6-dependent lineages. We conclude that distinct lineage-specific BTB-ZF transcription factors recruit CUL3 to alter the ubiquitination pattern of their associated chromatin-modifying complex. We propose that this new function is essential to direct the differentiation of several T- and B-cell effector programs, and may also be involved in the oncogenic role of PLZF and BCL6 in leukaemias and lymphomas.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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