375 research outputs found
Theology, News and Notes - Vol. 46, No. 02
Theology News & Notes was a theological journal published by Fuller Theological Seminary from 1954 through 2014.https://digitalcommons.fuller.edu/tnn/1136/thumbnail.jp
Ca2+ signaling modulates cytolytic T lymphocyte effector functions
Cytolytic T cells use two mechanisms to kill virally infected cells, tumor cells, or other potentially autoreactive T cells in short-term in vitro assays. The perforin/granule exocytosis mechanism uses preformed cytolytic granules that are delivered to the target cell to induce apoptosis and eventual lysis. FasL/Fas (CD95 ligand/CD95)–mediated cytolysis requires de novo protein synthesis of FasL by the CTL and the presence of the death receptor Fas on the target cell to induce apoptosis. Using a CD8+ CTL clone that kills via both the perforin/granule exocytosis and FasL/Fas mechanisms, and a clone that kills via the FasL/Fas mechanism only, we have examined the requirement of intra- and extracellular Ca2+ in TCR-triggered cytolytic effector function. These two clones, a panel of Ca2+ antagonists, and agonists were used to determine that a large biphasic increase in intracellular calcium concentration, characterized by release of Ca2+ from intracellular stores followed by a sustained influx of extracellular Ca2+, is required for perforin/granule exocytosis. Only the sustained influx of extracellular Ca2+ is required for FasL induction and killing. Thapsigargin, at low concentrations, induces this small but sustained increase in [Ca2+]i and selectively induces FasL/Fas-mediated cytolysis but not granule exocytosis. These results further define the role of Ca2+ in perforin and FasL/Fas killing and demonstrate that differential Ca2+ signaling can modulate T cell effector functions
DC-SIGN on B Lymphocytes Is Required For Transmission of HIV-1 to T Lymphocytes
Infection of T cells by HIV-1 can occur through binding of virus to dendritic cell (DC)-specific ICAM-3 grabbing nonintegrin (DC-SIGN) on dendritic cells and transfer of virus to CD4(+) T cells. Here we show that a subset of B cells in the blood and tonsils of normal donors expressed DC-SIGN, and that this increased after stimulation in vitro with interleukin 4 and CD40 ligand, with enhanced expression of activation and co-stimulatory molecules CD23, CD58, CD80, and CD86, and CD22. The activated B cells captured and internalized X4 and R5 tropic strains of HIV-1, and mediated trans infection of T cells. Pretreatment of the B cells with anti–DC-SIGN monoclonal antibody blocked trans infection of T cells by both strains of HIV-1. These results indicate that DC-SIGN serves as a portal on B cells for HIV-1 infection of T cells in trans. Transmission of HIV-1 from B cells to T cells through this DC-SIGN pathway could be important in the pathogenesis of HIV-1 infection
Recommended from our members
LDRD final report on high power broadly tunable Mid-IR quantum cascade lasers for improved chemical species detection.
The goal of our project was to examine a novel quantum cascade laser design that should inherently increase the output power of the laser while simultaneously providing a broad tuning range. Such a laser source enables multiple chemical species identification with a single laser and/or very broad frequency coverage with a small number of different lasers, thus reducing the size and cost of laser based chemical detection systems. In our design concept, the discrete states in quantum cascade lasers are replaced by minibands made of multiple closely spaced electron levels. To facilitate the arduous task of designing miniband-to-miniband quantum cascade lasers, we developed a program that works in conjunction with our existing modeling software to completely automate the design process. Laser designs were grown, characterized, and iterated. The details of the automated design program and the measurement results are summarized in this report
Challenging notions of gendered game play: teenagers playing `The Sims`
This paper challenges notions of gendered game playing practice implicit in much research into young women\u27s involvement with the computer gaming culture. It draws on a study of Australian teenagers playing The Sims Deluxe as part of an English curriculum unit and insights from feminist media studies to explore relationships between gender and game playing practices. Departing from a reliance on predetermined notions of “gender”, “domestic space”, and “successful game play”, it conceptualizes The Sims as a game in which the boundaries between gender and domestic space are disturbed. It argues that observing students\u27 constructions of gender and domestic space through the act of game play itself provides a more productive insight into the gendered dimensions of game play for educators wishing to work computer games such as The Sims into curriculum development.<br /
Recommended from our members
LDRD final report on continuous wave intersubband terahertz sources.
There is a general lack of compact electromagnetic radiation sources between 1 and 10 terahertz (THz). This a challenging spectral region lying between optical devices at high frequencies and electronic devices at low frequencies. While technologically very underdeveloped the THz region has the promise to be of significant technological importance, yet demonstrating its relevance has proven difficult due to the immaturity of the area. While the last decade has seen much experimental work in ultra-short pulsed terahertz sources, many applications will require continuous wave (cw) sources, which are just beginning to demonstrate adequate performance for application use. In this project, we proposed examination of two potential THz sources based on intersubband semiconductor transitions, which were as yet unproven. In particular we wished to explore quantum cascade lasers based sources and electronic based harmonic generators. Shortly after the beginning of the project, we shifted our emphasis to the quantum cascade lasers due to two events; the publication of the first THz quantum cascade laser by another group thereby proving feasibility, and the temporary shut down of the UC Santa Barbara free-electron lasers which were to be used as the pump source for the harmonic generation. The development efforts focused on two separate cascade laser thrusts. The ultimate goal of the first thrust was for a quantum cascade laser to simultaneously emit two mid-infrared frequencies differing by a few THz and to use these to pump a non-linear optical material to generate THz radiation via parametric interactions in a specifically engineered intersubband transition. While the final goal was not realized by the end of the project, many of the completed steps leading to the goal will be described in the report. The second thrust was to develop direct THz QC lasers operating at terahertz frequencies. This is simpler than a mixing approach, and has now been demonstrated by a few groups with wavelengths spanning 65-150 microns. We developed and refined the MBE growth for THz for both internally and externally designed QC lasers. Processing related issues continued to plague many of our demonstration efforts and will also be addressed in this report
Reticulated origin of domesticated emmer wheat supports a dynamic model for the emergence of agriculture in the fertile crescent
We used supernetworks with datasets of nuclear gene sequences and novel markers detecting retrotransposon insertions in ribosomal DNA loci to reassess the evolutionary relationships among tetraploid wheats. We show that domesticated emmer has a reticulated genetic ancestry, sharing phylogenetic signals with wild populations from all parts of the wild range. The extent of the genetic reticulation cannot be explained by post-domestication gene flow between cultivated emmer and wild plants, and the phylogenetic relationships among tetraploid wheats are incompatible with simple linear descent of the domesticates from a single wild population. A more parsimonious explanation of the data is that domesticated emmer originates from a hybridized population of different wild lineages. The observed diversity and reticulation patterns indicate that wild emmer evolved in the southern Levant, and that the wild emmer populations in south-eastern Turkey and the Zagros Mountains are relatively recent reticulate descendants of a subset of the Levantine wild populations. Based on our results we propose a new model for the emergence of domesticated emmer. During a pre-domestication period, diverse wild populations were collected from a large area west of the Euphrates and cultivated in mixed stands. Within these cultivated stands, hybridization gave rise to lineages displaying reticulated genealogical relationships with their ancestral populations. Gradual movement of early farmers out of the Levant introduced the pre-domesticated reticulated lineages to the northern and eastern parts of the Fertile Crescent, giving rise to the local wild populations but also facilitating fixation of domestication traits. Our model is consistent with the protracted and dispersed transition to agriculture indicated by the archaeobotanical evidence, and also with previous genetic data affiliating domesticated emmer with the wild populations in southeast Turkey. Unlike other protracted models, we assume that humans played an intuitive role throughout the process.Natural Environment Research Council [NE/E015948/1]; Slovak Research and Development Agency [APVV-0661-10, APVV-0197-10]info:eu-repo/semantics/publishedVersio
Central nervous system immune interactome is a function of cancer lineage, tumor microenvironment, and STAT3 expression.
BACKGROUNDImmune cell profiling of primary and metastatic CNS tumors has been focused on the tumor, not the tumor microenvironment (TME), or has been analyzed via biopsies.METHODSEn bloc resections of gliomas (n = 10) and lung metastases (n = 10) were analyzed via tissue segmentation and high-dimension Opal 7-color multiplex imaging. Single-cell RNA analyses were used to infer immune cell functionality.RESULTSWithin gliomas, T cells were localized in the infiltrating edge and perivascular space of tumors, while residing mostly in the stroma of metastatic tumors. CD163+ macrophages were evident throughout the TME of metastatic tumors, whereas in gliomas, CD68+, CD11c+CD68+, and CD11c+CD68+CD163+ cell subtypes were commonly observed. In lung metastases, T cells interacted with CD163+ macrophages as dyads and clusters at the brain-tumor interface and within the tumor itself and as clusters within the necrotic core. In contrast, gliomas typically lacked dyad and cluster interactions, except for T cell CD68+ cell dyads within the tumor. Analysis of transcriptomic data in glioblastomas revealed that innate immune cells expressed both proinflammatory and immunosuppressive gene signatures.CONCLUSIONOur results show that immunosuppressive macrophages are abundant within the TME and that the immune cell interactome between cancer lineages is distinct. Further, these data provide information for evaluating the role of different immune cell populations in brain tumor growth and therapeutic responses.FUNDINGThis study was supported by the NIH (NS120547), a Developmental research project award (P50CA221747), ReMission Alliance, institutional funding from Northwestern University and the Lurie Comprehensive Cancer Center, and gifts from the Mosky family and Perry McKay. Performed in the Flow Cytometry & Cellular Imaging Core Facility at MD Anderson Cancer Center, this study received support in part from the NIH (CA016672) and the National Cancer Institute (NCI) Research Specialist award 1 (R50 CA243707). Additional support was provided by CCSG Bioinformatics Shared Resource 5 (P30 CA046592), a gift from Agilent Technologies, a Research Scholar Grant from the American Cancer Society (RSG-16-005-01), a Precision Health Investigator Award from University of Michigan (U-M) Precision Health, the NCI (R37-CA214955), startup institutional research funds from U-M, and a Biomedical Informatics & Data Science Training Grant (T32GM141746)
- …