Cytotoxic dendritic cells generated from cancer patients.

International audienceKnown for years as professional APCs, dendritic cells (DCs) are also endowed with tumoricidal activity. This dual role of DC as killers and messengers may have important implications for tumor immunotherapy. However, the tumoricidal activity of DCs has mainly been investigated in animal models. Cancer cells inhibit antitumor immune responses using numerous mechanisms, including the induction of immunosuppressive/ tolerogenic DCs that have lost their ability to present Ags in an immunogenic manner. In this study, we evaluated the possibility of generating tumor killer DCs from patients with advanced-stage cancers. We demonstrate that human monocyte-derived DCs are endowed with significant cytotoxic activity against tumor cells following activation with LPS. The mechanism of DC-mediated tumor cell killing primarily involves peroxynitrites. This observed cytotoxic activity is restricted to immature DCs. Additionally, after killing, these cytotoxic DCs are able to activate tumor Ag-specific T cells. These observations may open important new perspectives for the use of autologous cytotoxic DCs in cancer immunotherapy strategies

Interaction between Coastal and Oceanic Ecosystems of the Western and Central Pacific Ocean through Predator-Prey Relationship Studies

The Western and Central Pacific Ocean sustains the highest tuna production in the world. This province is also characterized by many islands and a complex bathymetry that induces specific current circulation patterns with the potential to create a high degree of interaction between coastal and oceanic ecosystems. Based on a large dataset of oceanic predator stomach contents, our study used generalized linear models to explore the coastal-oceanic system interaction by analyzing predator-prey relationship. We show that reef organisms are a frequent prey of oceanic predators. Predator species such as albacore (Thunnus alalunga) and yellowfin tuna (Thunnus albacares) frequently consume reef prey with higher probability of consumption closer to land and in the western part of the Pacific Ocean. For surface-caught-predators consuming reef prey, this prey type represents about one third of the diet of predators smaller than 50 cm. The proportion decreases with increasing fish size. For predators caught at depth and consuming reef prey, the proportion varies with predator species but generally represents less than 10%. The annual consumption of reef prey by the yellowfin tuna population was estimated at 0.8±0.40CV million tonnes or 2.17×1012±0.40CV individuals. This represents 6.1%±0.17CV in weight of their diet. Our analyses identify some of the patterns of coastal-oceanic ecosystem interactions at a large scale and provides an estimate of annual consumption of reef prey by oceanic predators

« Our rural sense of place » Rurality and Strategies of Self-Segregation in the Cape Peninsula (South Africa)

The local use of so-called rurality as political ways to protect whiteness within the very segregated Cape Peninsula is informing on some racial resistance to post-apartheid change in South Africa. As the country as a whole, the Cape metropolis is marked by high socio-spatial inequalities. Post-apartheid spatial and demographic changes accelerated transformations of local governance. In that particular context, recent claims made by local resident’s associations to protect their rural identity - characterised by countryside place names, farming architecture and European cultural landscape,-appear to be a strategy of withdrawal opposed to urban sprawl and new metropolitan governance. Eventually, the defence of rurality seems to challenge spatial justice in favouring close-knit communities and socio-spatial segregation

A critique of the ecosystem impacts of drifting and anchored FADs use by purse-seine tuna fisheries in the Western and Central Pacific Ocean

In the Western and Central Pacific Ocean (WCPO), which accounts for over half of world tuna production, purse seine effort and catch on floating objects have increased significantly due to a rapid increase in the use of fixed and free-floating fish aggregation devices (FADs). FAD fishing has had an impact on the current status of the stocks of the three main target tunas in the equatorial WCPO, skipjack (Katsuwonus pelamis), yellowfin (Thunnus albacares) and bigeye (T. obesus). FADs have been shown to influence the behaviour and movement patterns of the three tuna species with the juveniles of each species occupying shallower habitats when associated with FADs. Aggregation of tunas around drifting objects increases their vulnerability to purse seine gear, particularly for juvenile and small size classes. Further to the impacts on the target stocks, the use of FADs has increased the vulnerability of other fishes to the purse seine method, including some shark and billfish species. Given the concern over FAD-related fishing effort on target and bycatch species, there is a need to understand how FAD use affects target and bycatch stocks. Science needs to better support management decisions are highlighted including the need to identify the magnitude of broader community-level affects

Results of GLM modeling presence-absence of reef prey in stomach contents of predators.

<p>Df, degree of freedom; Chisq, Deviance of the final model; p-value from Anova Chi-test; BIC, Bayesian Information Criterion. Significance codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1.</p

Locations of the 812 sets where samples were collected.

<p>Locations of the 812 sets where samples were collected.</p

Proportion by weight of reef prey in stomach content against predator’s species, the main explanatory variable, for all predators consuming reef prey and caught with longline gear.

<p>Predicted means with 95% confidence interval. Predator code: see caption of <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0036701#pone-0036701-g001" target="_blank">figure 1</a>. No rainbow runner (RRU) was caught with longline gear.</p

The reversed halo sign : pathognomonic pattern of pulmonary mucormycosis in leukemic patients with neutropenia ?

Equipe EA MERSInternational audiencePulmonary mucormycosis (PM) is a life-threatening fungal infection with an increasing incidence among patients with acute leukemia. In some immunocompromised hosts, the reversed halo sign (RHS) has been described on the pulmonary computed tomographic (CT) scan of patients with mucormycosis. Methods. This study reports a single-center experience with PM exclusively in patients with acute leukemia. Clinical records, laboratory results, and CT scans were retrospectively analyzed to evaluate the clinical usefulness of the RHS for the early identification and treatment of PM, with regard to outcomes in these patients. Results. Between 2003 and 2012, 16 cases of proven PM were diagnosed among 752 consecutive patients receiving chemotherapy for acute myeloblastic or lymphoblastic leukemia. At the time PM was diagnosed, all patients but one were neutropenic. The study of sequential thoracic CT scans showed that during the first week of the disease, the RHS was observed in 15 of 16 patients (94%). Initially, other radiologic findings (multiple nodules and pleural effusion) were less frequent, but appeared later in the course of the disease (6% and 12% before vs 64% and 55% after the first week). After the diagnosis of PM, median overall survival was 25 weeks (range, 3-193 weeks), and 6 patients (38%) died before day 90. Conclusions. In the particular setting of neutropenic leukemia patients with pulmonary infection, the presence of the RHS on CT was a strong indicator of PM. It could allow the early initiation of appropriate therapy and thus improve the outcome

Antiplatelet Antibodies Do Not Predict the Response to Intravenous Immunoglobulins during Immune Thrombocytopenia

Immune thrombocytopenia (ITP) is a rare autoimmune disease due to autoantibodies targeting platelet glycoproteins (GP). The mechanism of platelet destruction could differ depending on the specificity of antiplatelet antibodies: anti-GPIIb/IIIa antibodies lead to phagocytosis by splenic macrophages, in a Fc&gamma; receptor (Fc&gamma;R)-dependent manner while anti-GPIb/IX antibodies induce platelet desialylation leading to their destruction by hepatocytes after binding to the Ashwell&ndash;Morell receptor, in a Fc&gamma;R-independent manner. Considering the Fc&gamma;R-dependent mechanism of action of intravenous immunoglobulins (IVIg), we assumed that the response to IVIg could be less efficient in the presence of anti-GPIb/IX antibodies. We conducted a multicentric, retrospective study including all adult ITP patients treated with IVIg who had antiplatelet antibodies detected between January 2013 and October 2017. Among the 609 identified, 69 patients were included: 17 had anti-GPIb/IX antibodies and 33 had anti-GPIIb/IIIa antibodies. The response to IVIg was not different between the patients with or without anti-GPIb/IX (88.2% vs. 73.1%). The response to IVIg was better in the case of newly diagnosed ITP (odds ratio (OR) = 5.4 (1.2&ndash;24.7)) and in presence of anti-GPIIb/IIIa (OR = 4.82 (1.08&ndash;21.5)), while secondary ITP had a poor response (OR = 0.1 (0.02&ndash;0.64)). In clinical practice, the determination of antiplatelet antibodies is therefore of little value to predict the response to IVIg