Differential Regulation of the Immune Response in the Spleen and Liver of Mice Infected with Leishmania donovani

Immunity to pathogens requires generation of effective innate and adaptive immune responses. Leishmania donovani evades these host defense mechanisms to survive and persist in the host. A better understanding and identification of mechanisms that L. donovani employs for its survival is critical for developing novel therapeutic interventions that specifically target the parasite. This paper will highlight some of the mechanisms that the parasite utilizes for its persistence and also discuss how the immune response is regulated

CD8+ T Cells in Leishmania Infections: Friends or Foes?

Host protection against several intracellular pathogens requires the induction of CD8+ T cell responses. CD8+ T cells are potent effector cells that can produce high amounts of pro-inflammatory cytokines and kill infected target cells efficiently. However, a protective role for CD8+ T cells during Leishmania infections is still controversial and largely depends on the infection model. In this review, we discuss the role of CD8+ T cells during various types of Leishmania infections, following vaccination, and as potential immunotherapeutic targets

What Am I Drinking? Vision Modulates the Perceived Flavor of Drinks, but No Evidence of Flavor Altering Color Perception in a Mixed Reality Paradigm

It is well established that vision, and in particular color, may modulate our experience of flavor. Such cross-modal correspondences have been argued to be bilateral, in the sense that one modality can modulate the other and vice versa. However, the amount of literature assessing how vision modulates flavor is remarkably larger than that directly assessing how flavor might modulate vision. This is more exaggerated in the context of cross-modal contrasts (when the expectancy in one modality contrasts the experience through another modality). Here, using an embodied mixed reality setup in which participants saw a liquid while ingesting a contrasting one, we assessed both how vision might modulate basic dimensions of flavor perception and how the flavor of the ingested liquid might alter the perceived color of the seen drink. We replicated findings showing the modulation of flavor perception by vision but found no evidence of flavor modulating color perception. These results are discussed in regard to recent accounts of multisensory integration in the context of visual modulations of flavor and bilateral cross-modulations. Our findings might be important as a step in understanding bilateral visual and flavor cross-modulations (or the lack of them) and might inform developments using embodied mixed reality technologies

IRF-5-Mediated Inflammation Limits CD8+ T Cell Expansion by Inducing HIF-1α and Impairing Dendritic Cell Functions during Leishmania Infection.

International audienceInflammation is known to be necessary for promoting, sustaining, and tuning CD8+ T cell responses. Following experimental Leishmania donovani infection, the inflammatory response is mainly induced by the transcription factor IRF-5. IRF-5 is responsible for the activation of several genes encoding key pro-inflammatory cytokines, such as IL-6 and TNF. Here, we investigate the role of IRF-5-mediated inflammation in regulating antigen-specific CD8+ T cell responses during L. donovani infection. Our data demonstrate that the inflammatory response induced by IRF-5 limits CD8+ T cell expansion and induces HIF-1α in dendritic cells. Ablation of HIF-1α in CD11c+ cells resulted into a higher frequency of short-lived effector cells (SLEC), enhanced CD8+ T cell expansion, and increased IL-12 expression by splenic DCs. Moreover, mice with a targeted depletion of HIF-1α in CD11c+ cells had a significantly lower splenic parasite burden, suggesting that induction of HIF-1α may represent an immune evasive mechanism adopted by Leishmania parasites to establish persistent infections

Disproportionately High Contributions of 60 Year Old Weapons-137Cs Explain the Persistence of Radioactive Contamination in Bavarian Wild Boars

Radionuclides released from nuclear accidents or explosions pose long-term threats to ecosystem health. A prominent example is wild boar contamination in central Europe, which is notorious for its persistently high 137Cs levels. However, without reliable source identification, the origin of this decades old problem has been uncertain. Here, we target radiocesium contamination in wild boars from Bavaria. Our samples (2019-2021) range from 370 to 15,000 Bq·kg-1137Cs, thus exceeding the regulatory limits (600 Bq·kg-1) by a factor of up to 25. Using an emerging nuclear forensic fingerprint, 135Cs/137Cs, we distinguished various radiocesium source legacies in their source composition. All samples exhibit signatures of mixing of Chornobyl and nuclear weapons fallout, with 135Cs/137Cs ratios ranging from 0.67 to 1.97. Although Chornobyl has been widely believed to be the prime source of 137Cs in wild boars, we find that “old” 137Cs from weapons fallout significantly contributes to the total level (10-68%) in those specimens that exceeded the regulatory limit. In some cases, weapons-137Cs alone can lead to exceedances of the regulatory limit, especially in samples with a relatively low total 137Cs level. Our findings demonstrate that the superposition of older and newer legacies of 137Cs can vastly surpass the impact of any singular yet dominant source and thus highlight the critical role of historical releases of 137Cs in current environmental pollution challenges

Status of the search for a muon EDM using the frozen-spin technique

Despite the many successes of the Standard Model of particle physics, there are still several physical observations that it cannot explain, such as the matter-antimatter asymmetry, non-zero neutrino masses, and the microscopic nature of dark matter. To address these limitations, extensions to the standard model are necessary, and searches for electric dipole moments (EDMs) of leptons are valuable test. The search for a muon EDM is the only search on a bare lepton of the second generation, complementing the searches for an EDM of the electron using polar molecules. A non-zero EDM of the muon would indicate Charge-Parity symmetry violation beyond the standard model. A dedicated experimental search for the muon EDM is being set up at PSI using the frozen-spin technique. In this technique, the anomalous spin precession of the muons in a storage ring is suppressed by applying an electric field in the radial direction. The muon EDM experiment will take place in two phases: the first phase will demonstrate the frozen-spin technique using a precursor experiment with 28 MeV/c muons, while the second phase will make use of 125 MeV/c muons, which could search for the muon EDM with a sensitivity of 6 × 10-23 e·cm. In this talk, we describe the precursor experiment at PSI and provide an update on the status of the experiment

Multicenter EuroTravNet/GeoSentinel Study of Travel-related Infectious Diseases in Europe

We analyzed prospective data on 17,228 European patients who sought treatment at GeoSentinel sites from 1997 to 2007. Gastrointestinal illness (particularly in tourists), fever (those visiting friends and relatives [VFRs]), and skin disorders (in tourists) were the most common reasons for seeking medical care. Diagnoses varied by country of origin, region visited, or categories of travelers. VFRs who returned from sub-Saharan Africa and Indian Ocean islands were more likely to experience falciparum malaria than any other group. Multiple correspondence analysis identified Italian, French, and Swiss VFRs and expatriate travelers to sub-Saharan Africa and Indian Ocean Islands as most likely to exhibit febrile illnesses. German tourists to Southeast and south-central Asia were most likely to seek treatment for acute diarrhea. Non-European travelers (12,663 patients from other industrialized countries) were less likely to acquire certain travel-associated infectious diseases. These results should be considered in the practice of travel medicine and development of health recommendations for European travelers