1,721,283 research outputs found
Is FOXP3 a bona fide marker for human regulatory T cells?
No full textFOXP3 is a specific marker for naturally occurring regulatory T cells (nTreg). FOXP3 expression is correlated with development and function of nTreg. Recent evidence suggests that, upon activation, human effector T (Teff) cells and type 1 regulatory T (Tr1) cells can express FOXP3, albeit transiently. While the role of transient FOXP3 expression in Teff cells is poorly understood, it is becoming clear that it does not correlate with suppressor function. Furthermore, FOXP3-independent mechanisms, mediated by IL-10, contribute to the induction and suppressor functions of Tr1 cells
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Role of human leukocyte antigen-G in the induction of adaptive type 1 regulatory T cells
No full textAdaptive type I regulatory T (Tr1) cells are suppressor cells characterized by the production of interleukin (IL)-10 in the absence of IL-4. IL-10 is essential not only for suppression of effector cells by Tr1 cells, but also for their differentiation in vitro and in vivo. However, little is known on the molecular mechanisms underneath the IL-10-mediated induction of Tr1 cells. Human Leukocyte Antigen (HLA)-G, a non-classical HLA class I molecule, has both direct inhibitory effects on natural killer cells, dendritic cells (DC), and T cells and long-term tolerogenic indirect effects by inducing regulatory T (Tr) cells. in the present review, we discuss current findings on Tr-cell induction by the different isoforms of HLA-G, focusing on the relationship among HLA-G, its ligands, and IL-10. We recently described a subset of human DC, termed DC-10, that express high levels of HLA-G and ILT4, secrete high amounts of IL-10, and induce allospecific Tr1 cells in vitro via an IL-10-dependent ILT4/HLA-G pathway. IL-10, HLA-G, and ILT4 may also be involved in Tr1-cell induction in vivo. Overall, these data demonstrate that cross-regulation between IL-10 and HLA-G may be instrumental for Tr1-cell induction and tolerance. (C) 2009 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved
CD4+ regulatory T cells: mechanisms of induction and effector function
No full texthe main subsets of CD4(+) regulatory T (Tr) cells are the CD4(+) CD25(+) Tr cells and the type 1 regulatory (Tr1) cells. Both subsets are essential for the maintenance of peripheral tolerance. CD4(+) CD25(+) Tr cells control immune homeostasis (e.g., in autoimmunity) mainly by cell contact-dependent interactions. In contrast, Tr1 cells regulate immune responses in transplantation, allergy, and autoirnmune diseases, via an IL-10- and TGF-beta-dependent mechanism. Identification of the mechanisms responsible for the induction of the different Tr subsets in vivo is a matter of intense investigation. Studies on dendritic cells (DC), performed in the last years by several groups, have significantly contributed to clarify this point. Indeed, it is now clear that the role of DCs is not only to sense danger, but also to tolerize the immune system to antigens (Ags) encountered in the absence of maturation/inflammatory stimuli. Therefore, if a naive T cell encounters the antigen on immature DCs (iDCs), it differentiates into a Tr cell rather than an effector T cell.
A better understanding of the mechanisms underlying the induction and functions of Tr cells in controlling the immune system is critical in view of a future cellular therapy to modulate immune-mediated pathologies
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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