Compartmentalized control of skin immunity by resident commensals

Intestinal commensal bacteria induce protective and regulatory responses that maintain host-microbial mutualism. However, the contribution of tissue-resident commensals to immunity and inflammation at other barrier sites has not been addressed. We found that in mice, the skin microbiota have an autonomous role in controlling the local inflammatory milieu and tuning resident T lymphocyte function. Protective immunity to a cutaneous pathogen was found to be critically dependent on the skin microbiota but not the gut microbiota. Furthermore, skin commensals tuned the function of local T cells in a manner dependent on signaling downstream of the interleukin-1 receptor. These findings underscore the importance of the microbiota as a distinctive feature of tissue compartmentalization, and provide insight into mechanisms of immune system regulation by resident commensal niches in health and disease.     

Linking research and public engagement: weaving an alternative narrative of Moroccan family farmers’ collective action

Rural development policies are often inspired by narratives that are difficult to challenge because they are based on an apparently obvious and coherent reading of reality. Research may confront such narratives and trigger debates outside the academic community, but this can have a feedback effect and lead to a simplistic or biased posture in research. This article analyzes a research-based initiative that questioned a commonly held narrative in large-scale irrigation schemes in Morocco concerning the structural weaknesses of farmer-led collective action. This initiative conceived an alternative narrative of farmer-led collective action, based on research and actions undertaken in collaboration with the farmers. The article assesses to what extent it was possible to design this narrative and to draw on it to orient research activities, actions with farmers and public engagement, without impairing the quality of the research process. The alternative narrative was designed and diffused based on three intertwined activities: (1) the identification and analysis of farmer-led collective actions, (2) the diffusion of information on successful farmer-led collective actions especially through the production of videos, and (3) exchanges with and between local farmers’ organizations. The alternative narrative that resulted from these activities emphasizes the potentialities of farmer-led collective action, and more broadly, the willingness and capabilities of many family farmers to play an active role in the governance of rural areas. The message of the alternative narrative and the distinction made between the research articles and videos in both their content and role ensured that research did not fall into simplistic or biased analyses. The alternative narrative also became a key to renewed relations between farmers and researchers and helped design training for students that pay more attention to local dynamics. In a situation in which scheme-level organizations show limited interest in reflexive enquiry, this initiative proposes some stepping stones to make it possible for changing narratives to accompany changing relations between actors.     

Immunogenicity of eight Mycobacterium avium subsp. paratuberculosis specific antigens in DNA vaccinated and Map infected mice

Mycobacterium avium subsp. paratuberculosis (Map), the etiological agent of chronic enteritis of the small intestine in domestic and wild ruminants, causes substantial losses to livestock industry. Control of this disease is seriously hampered by the lack of adequate diagnostic tools and vaccines. Here we report on the immunogenicity of eight Map specific antigens, i.e. MAP1693c, Ag3, MAP2677c (identified by post-genomic and immunoproteomic analysis of Map secretome) and Ag5, Ag6, MAP1637c, MAP0388 and MAP3743 (identified by bioinformatic in silico screening of the Map genome). Strong, antigen-specific IFN-γ responses were induced in mice vaccinated with plasmid DNA encoding MAP1693c, MAP1637c, MAP0388 and MAP3743. In contrast, T cell responses in Map infected mice were directed preferentially against Ag5 and to a lesser extent against MAP3743. None of the tested DNA vaccines conferred protection against subsequent challenge with Map.     

Bovine mammary dendritic cells: a heterogeneous population, distinct from macrophages and similar in phenotype to afferent lymph veiled cells

Dendritic cells (DC) are a heterogeneous population of professional antigen presenting cells and are potent stimulators of na?ve T-cells. However, there is little previous research describing DC in bovine mammary tissue, primarily because of the difficulty distinguishing these cells from macrophages, which possess a similar phenotype. Using immunohistofluorescence and a combination of markers (MHC-II, CD205, CD11c), DC were localized in the bovine mammary gland and supramammary lymph node. In mammary tissue DC were found within the alveolar epithelium and within the intralobular connective tissue. In the lymph node DC were found on the periphery of B-cell areas, in the cortex, and among T-cells in the paracortex and medulla. DC in mammary parenchyma and supramammary lymph nodes were quantified and further characterized using flow cytometry. DC were CD11c(hi), CD14(lo) cells that expressed MHC-II and CD205. DC could be distinguished from macrophages based on their low CD14 expression. This research provides a better understanding of mammary gland immunology, while potentially aiding in the targeting of antigens to mucosal DC for vaccine development.     

Potential for using Datura alba leaf extracts against two major stored grain pests, the khapra beetle Trogoderma granarium and the rice weevil Sitophillus oryzae

Various plants are well known for their insecticidal activity and their use was maintained for millennia throughout all the agricultural regions of the world. In a current context, the use of Botanical insecticides represents one of the best alternatives to chemicals for the development of environmental-friendly strategies for stored grain pest control. Datura alba Nees is a plant found extensively in the warmer regions of the world and it is used as a medicinal plant. This study aims to assess the contact toxicity and the trans-generational effect of D.?alba leaf extract (DLE) against two important insect pests on stored rice, Trogoderma granarium and Sitophilus oryzae, under laboratory conditions. Filter papers were soaked in three DLE concentration solutions and in two control treatments: water and acetone. The survivor specimens (F₀) were transferred to a new untreated feeding substrate and the population build up of the two following generations (F₁ and F₂) were counted after 30 and 60?days, respectively. The highest DLE concentration (2.5?%) induced the significantly highest mortality with 33.5 and 45?% mortality in T.?granarium and S.?oryzae after 7?days of exposure, respectively. The DLE long-term effect toward both tested species was also proved by the high demographic decrease in the F₂ generations, when compared to control groups. This study is the first step toward establishing a scientific basis for the effective application of D.?alba plant materials as biorational tools to control stored grain pests.     

Gas exchange and leaf aging in an evergreen oak: causes and consequences for leaf carbon balance and canopy respiration

Leaves of Mediterranean evergreens experience large variations in gas exchange rates over their life span due to aging and seasonally changing environmental conditions. Accounting for the changing respiratory physiology of leaves over time will help improve estimations of leaf and whole-plant carbon balances. Here we examined seasonal variations in light-saturated net CO(2) assimilation (A(max)), dark respiration (R(d)) and the proportional change in R(d) per 10 °C change in temperature (Q(10) of R(d)) in previous-year (PY) and current-year (CY) leaves of the broadleaved evergreen tree Quercus ilex L. A(max) and R(d) were lower in PY than in CY leaves. Differences in nitrogen between cohorts only partly explained such differences, and rates of A(max) and R(d) expressed per unit of leaf nitrogen were still significantly different between cohorts. The decline in A(max) in PY leaves did not result in the depletion of total non-structural carbohydrates, whose concentration was in fact higher in PY than CY leaves. Leaf-level carbon balance modeled from gas exchange data was positive at all ages. Q(10) of R(d) did not differ significantly between leaf cohorts; however, failure to account for distinct R(d) between cohorts misestimated canopy leaf respiration by 13% across dates when scaling up leaf measurements to the canopy. In conclusion, the decline in A(max) in old leaves that are close to or exceed their mean life span does not limit the availability of carbohydrates, which are probably needed to sustain new growth, as well as R(d) and nutrient resorption during senescence. Accounting for leaf age as a source of variation of R(d) improves the estimation of foliar respiratory carbon release at the stand scale.     

Fatal overdose after ingestion of a transdermal fentanyl patch in two non‐human primates

Case history and presentationTwo non-human primates (Macaca fascicularis), weight 3.5 kg, enrolled in an experimental protocol received a 25 μg hour^?1 transdermal fentanyl patch for postoperative analgesia. The following day both animals were clinically normal, but after a new induction of anaesthesia with ketamine, they developed severe and prolonged respiratory distress, profound coma and myosis.Management and follow-upAttempted reversal with naloxone was ineffective. After several hours of ventilation, both primates eventually died, 7 and 15 hours after ketamine injection, respectively. In both cases, the patch was discovered in the animal's cheek pouch. Subsequent fentanyl serum concentration measurements (8.29 and 14.80 μg L^?1) confirmed fentanyl overdose.ConclusionsThis report of two fatal intoxications in non-human primates secondary to ingestion of a transdermal fentanyl patch demonstrates that this method of analgesia is inappropriate for non-human primates, because of their tendency to chew almost anything they can reach.