University of Rijeka

About: University of Rijeka is a education organization based out in Rijeka, Croatia. It is known for research contribution in the topics: Population & Tourism. The organization has 3471 authors who have published 7993 publications receiving 110386 citations. The organization is also known as: Rijeka University & Sveučilište u Rijeci.

Mouse TIGIT inhibits NK-cell cytotoxicity upon interaction with PVR

Abstract: The activity of natural killer (NK) cells is controlled by a balance of signals derived from inhibitory and activating receptors. TIGIT is a novel inhibitory receptor, recently shown in humans to interact with two ligands: PVR and Nectin2 and to inhibit human NK-cell cytotoxicity. Whether mouse TIGIT (mTIGIT) inhibits mouse NK-cell cytotoxicity is unknown. Here we show that mTIGIT is expressed by mouse NK cells and interacts with mouse PVR. Using mouse and human Ig fusion proteins we show that while the human TIGIT (hTIGIT) cross-reacts with mouse PVR (mPVR), the binding of mTIGIT is restricted to mPVR. We further demonstrate using surface plasmon resonance (SPR) and staining with Ig fusion proteins that mTIGIT binds to mPVR with higher affinity than the co-stimulatory PVR-binding receptor mouse DNAM1 (mDNAM1). Functionally, we show that triggering of mTIGIT leads to the inhibition of NK-cell cytotoxicity, that IFN-γ secretion is enhanced when mTIGIT is blocked and that the TIGIT-mediated inhibition is dominant over the signals delivered by the PVR-binding co-stimulatory receptors. Additionally, we identify the inhibitory motif responsible for mTIGIT inhibition. In conclusion, we show that TIGIT is a powerful inhibitory receptor for mouse NK cells.

OGLE-2005-BLG-071Lb, THE MOST MASSIVE M DWARF PLANETARY COMPANION?

Abstract: We combine all available information to constrain the nature of OGLE-2005-BLG-071Lb, the second planet discovered by microlensing and the first in a high-magnification event. These include photometric and astrometric measurements from the Hubble Space Telescope, as well as constraints from higher order effects extracted from the ground-based light curve, such as microlens parallax, planetary orbital motion, and finite-source effects. Our primary analysis leads to the conclusion that the host of Jovian planet OGLE-2005-BLG-071Lb is an M dwarf in the foreground disk with mass M = 0.46 ± 0.04 Msun, distance Dl = 3.2 ± 0.4 kpc, and thick-disk kinematics vLSR ~ 103 km s‑1. From the best-fit model, the planet has mass Mp = 3.8 ± 0.4 MJupiter, lies at a projected separation r⊥ = 3.6 ± 0.2AU from its host, and so has an equilibrium temperature of T ~ 55 K, that is, similar to Neptune. A degenerate model gives similar planetary mass Mp = 3.4 ± 0.4 MJupiter with a smaller projected separation, r⊥ = 2.1 ± 0.1AU, and higher equilibrium temperature, T ~ 71 K. These results from the primary analysis suggest that OGLE-2005-BLG-071Lb is likely to be the most massive planet yet discovered that is hosted by an M dwarf. However, the formation of such high-mass planetary companions in the outer regions of M dwarf planetary systems is predicted to be unlikely within the core-accretion scenario. There are a number of caveats to this primary analysis, which assumes (based on real but limited evidence) that the unlensed light coincident with the source is actually due to the lens, that is, the planetary host. However, these caveats could mostly be resolved by a single astrometric measurement a few years after the event.

Efficacious control of cytomegalovirus infection after long-term depletion of CD8+ T lymphocytes.

Abstract: Although the relative contribution of different immune effector functions to clearing tissues of cytomegalovirus is controversial, the contribution of CD8+ T lymphocytes has generally been accepted as essential. In this report, we show that under certain conditions the CD8+ T-lymphocyte subset can be dispensable for clearance of cytomegalovirus. Mice depleted of the CD8+ T-lymphocyte subset eliminated infectious virus with a clearance kinetics similar to that of normal mice. Adoptive transfer studies revealed that the limitation of virus spread required the cooperation between the CD4+ subset and other cells. Comparison between protective functions generated in fully immunocompetent and in CD8- mice demonstrated that elimination of the CD8+ subset before infection altered the quality of the antiviral immune response. The compensatory protective activity gained by CD4+ cells in CD8- mice was absent in normal mice recovering from virus infection.

A mouse cytomegalovirus glycoprotein, gp34, forms a complex with folded class I MHC molecules in the ER which is not retained but is transported to the cell surface

Abstract: Murine cytomegalovirus (MCMV) interferes with antigen presentation by means of retaining major histocompatibility complex (MHC) class I molecules in the endoplasmic reticulum (ER). Here we identify and characterize an MCMV-encoded glycoprotein, gp34, which tightly associates with properly conformed MHC class I molecules in the ER. Gp34 is synthesized in large quantities during MCMV infection and it leaves the ER only in association with MHC class I complexes. Many but not all class I molecules are retained in the ER during the early phase of MCMV infection, and we observe an inverse correlation between amounts of gp34 synthesized during the course of infection and class I retention. An MCMV deletion mutant lacking several genes, including the gene encoding gp34, shows increased class I retention. Thus, MCMV gp34 may counteract class I retention, perhaps to decrease susceptibility of infected cells to recognition by natural killer cells.

Dynamic Consent: a potential solution to some of the challenges of modern biomedical research

Abstract: Background Innovations in technology have contributed to rapid changes in the way that modern biomedical research is carried out. Researchers are increasingly required to endorse adaptive and flexible approaches to accommodate these innovations and comply with ethical, legal and regulatory requirements. This paper explores how Dynamic Consent may provide solutions to address challenges encountered when researchers invite individuals to participate in research and follow them up over time in a continuously changing environment. Methods An interdisciplinary workshop jointly organised by the University of Oxford and the COST Action CHIP ME gathered clinicians, researchers, ethicists, lawyers, research participants and patient representatives to discuss experiences of using Dynamic Consent, and how such use may facilitate the conduct of specific research tasks. The data collected during the workshop were analysed using a content analysis approach. Results Dynamic Consent can provide practical, sustainable and future-proof solutions to challenges related to participant recruitment, the attainment of informed consent, participant retention and consent management, and may bring economic efficiencies. Conclusions Dynamic Consent offers opportunities for ongoing communication between researchers and research participants that can positively impact research. Dynamic Consent supports inter-sector, cross-border approaches and large scale data-sharing. Whilst it is relatively easy to set up and maintain, its implementation will require that researchers re-consider their relationship with research participants and adopt new procedures.