IFN-λ uniquely promotes CD8 T cell immunity against SARS-CoV-2 relative to type I IFN.

Optimization of protective immune responses against SARS-CoV-2 remains an urgent worldwide priority. In this regard, type III IFN (IFN-λ) restricts SARS-CoV-2 infection in vitro, and treatment with IFN-λ limits infection, inflammation, and pathogenesis in murine models. Furthermore, IFN-λ has been developed for clinical use to limit COVID-19 severity. However, whether endogenous IFN-λ signaling has an effect on SARS-CoV-2 antiviral immunity and long-term immune protection in vivo is unknown. In this study, we identified a requirement for IFN-λ signaling in promoting viral clearance and protective immune programming in SARS-CoV-2 infection of mice. Expression of both IFN and IFN-stimulated gene (ISG) in the lungs were minimally affected by the absence of IFN-λ signaling and correlated with transient increases in viral titers. We found that IFN-λ supported the generation of protective CD8 T cell responses against SARS-CoV-2 by facilitating accumulation of CD103+ DC in lung draining lymph nodes (dLN). IFN-λ signaling specifically in DCs promoted the upregulation of costimulatory molecules and the proliferation of CD8 T cells. Intriguingly, antigen-specific CD8 T cell immunity to SARS-CoV-2 was independent of type I IFN signaling, revealing a nonredundant function of IFN-λ. Overall, these studies demonstrate a critical role for IFN-λ in protective innate and adaptive immunity upon infection with SARS-CoV-2 and suggest that IFN-λ serves as an immune adjuvant to support CD8 T cell immunity.

Gasdermin D promotes influenza virus-induced mortality through neutrophil amplification of inflammation.

Influenza virus activates cellular inflammasome pathways, which can be both beneficial and detrimental to infection outcomes. Here, we investigate the function of the inflammasome-activated, pore-forming protein gasdermin D (GSDMD) during infection. Ablation of GSDMD in knockout (KO) mice (Gsdmd-/-) significantly attenuates influenza virus-induced weight loss, lung dysfunction, lung histopathology, and mortality compared with wild type (WT) mice, despite similar viral loads. Infected Gsdmd-/- mice exhibit decreased inflammatory gene signatures shown by lung transcriptomics. Among these, diminished neutrophil gene activation signatures are corroborated by decreased detection of neutrophil elastase and myeloperoxidase in KO mouse lungs. Indeed, directly infected neutrophils are observed in vivo and infection of neutrophils in vitro induces release of DNA and tissue-damaging enzymes that is largely dependent on GSDMD. Neutrophil depletion in infected WT mice recapitulates the reductions in mortality, lung inflammation, and lung dysfunction observed in Gsdmd-/- animals, while depletion does not have additive protective effects in Gsdmd-/- mice. These findings implicate a function for GSDMD in promoting lung neutrophil responses that amplify influenza virus-induced inflammation and pathogenesis. Targeting the GSDMD/neutrophil axis may provide a therapeutic avenue for treating severe influenza.

Protocol for detection of in vitro R-loop formation using dot blots.

Dot-blot analysis is a technique that allows for fast and convenient detection and identification of nucleic acids and proteins. Here, we provide a guide for nucleic acid isolation from eukaryotic cells and sample processing to detect RNA/DNA hybrids. We then provide detailed steps to quantify dot signal intensity. This protocol can be adapted for screening conditions that result in the accumulation of R-loops. For complete details on the use and execution of this protocol, please refer to Smith et al.1.

Pleural macrophages translocate to the lung during infection to promote improved influenza outcomes.

Seasonal influenza results in 3 to 5 million cases of severe disease and 250,000 to 500,000 deaths annually. Macrophages have been implicated in both the resolution and progression of the disease, but the drivers of these outcomes are poorly understood. We probed mouse lung transcriptomic datasets using the Digital Cell Quantifier algorithm to predict immune cell subsets that correlated with mild or severe influenza A virus (IAV) infection outcomes. We identified a unique lung macrophage population that transcriptionally resembled small serosal cavity macrophages and whose presence correlated with mild disease. Until now, the study of serosal macrophage translocation in the context of viral infections has been neglected. Here, we show that pleural macrophages (PMs) migrate from the pleural cavity to the lung after infection with IAV. We found that the depletion of PMs increased morbidity and pulmonary inflammation. There were increased proinflammatory cytokines in the pleural cavity and an influx of neutrophils within the lung. Our results show that PMs are recruited to the lung during IAV infection and contribute to recovery from influenza. This study expands our knowledge of PM plasticity and identifies a source of lung macrophages independent of monocyte recruitment and local proliferation.

Ensayo de reproducción inducida en Ariopsis seemanni / Induced spawning trial with Ariopsis seemanni / Ensajo de reprodução induzida em Ariopsis seemanni

Resumen El bagre marino Ariopsis seemanni es aprovechado como pez de consumo en la alimentación de pescadores y pobladores de la región pacifica colombiana y como pez ornamental (5 a 10 cm -longitud total), a nivel comercial nacional e internacional. En Colombia esta especie ha sido priorizada en la agenda nacional de investigación en acuicultura de 2011-2012, como una de las especies marinas potenciales en actividades acuícolas. El objetivo de esta investigación fue evaluar el efecto de la gonadotropina coriónica humana (HGC) y el extracto pituitario de carpa (EPC) sobre la maduración final y el desove en hembras adultas de la especie. Se utilizaron 24 parejas de peces silvestres capturadas del medio, con un peso promedio de 263.6±42.2 g y 174.4±30.4 g para hembras y machos, respectivamente. Se utilizaron cuatro tratamientos hormonales: T1: 5 mg EPC/kg; T2: 7 mg EPC/kg; T3: 2000 UI HGC/kg y T4: 1000 UI HGC/kg. Se identificaron tres tipos de oocitos en maduración, no se presentaron diferencias estadísticamente significativas (p>0,05) entre los tratamientos utilizados y la cantidad de oocitos en maduración; no se obtuvo desove espontaneo en ninguna de las hembras inducidas con las dosis hormonales empleadas.

Abstract The tete sea catfish Ariopsis seemanni is a fish used for human consumption by fishermen and residents along the coast of Colombia and as ornamental fish (5 to 10 cm -total longitude), at national and international comercial level. In Colombia, this species has been prioritized in the national aquaculture research agenda 2011-2012, as one of the potential marine species for aquaculture activities. This research was aimed at evaluating the effect of human chorionic gonadotropin (HGC) and carp pituitary extract (EPC) on final maturation and spawning adult females of the species. 24 pairs of wild fish were used, with an average weight of 263.6±42.2 g and 174.4±30.4 g for females and males, respectively. Four hormonal treatments was be used: T1: EPC 5 mg/kg; T2: EPC 7 mg/kg; T3: HGC 2000 IU/kg and T4: HGC 1000 IU/kg. Identify three types of maturation oocytes was. There were no statistically significant differences (p>0,05) between treatments used and the number of oocytes achieving maturation. No spontaneous spawning was obtained in any of the females induced with the hormonal doses used.

Resumo O bagre marino Ariopsis seemanni é aproveitado como peixe de consumo na alimentação de pescadores e moradores da região pacifica colombiana e como peixe ornamental (5 a 10 cm de comprimento), a nível comercial nacional e internacional. Na Colômbia A. seemanni tem sido priorizado na agenda nacional de pesquisa na aquicultura de 2011-2012, como uma das espécies marinhas potenciais em atividades aquícolas. Esta pesquisa teve como objetivo avaliar o efeito da gonadotrofina coriónica humana (GCH) e o extrato pituitário de carpa (EPC) sobre a maduração final e o desove em fêmeas adultas desta espécie. Utilizaram-se 24 casais de peixes retirados do meio natural, com um peso médio de 263,6 ± 42,2 g e 174,4 ± 30,4 g para fêmeas e machos, respectivamente. Empregaram-se quatro tratamentos hormonais: T1: 5 mg EPC/kg; T2: 7 mg EPC/kg; T3: 2000 UI HGC/kg e T4: 1000 UI HGC/kg. Identificaram-se três tipos de oócitos em maduração, não houve diferencias estatisticamente significativas (p>0,05) entre os tratamentos utilizados e a quantidade de oócitos em maturação; não foi possível obter desove espontâneo em nenhuma das fêmeas induzidas com as doses hormonais empregadas.

Exposición a plaguicidas en los habitantes de la ribera del río Bogotá (Suesca) y en el pez Capitán / Exposure to Pesticides in Residents or the Banks of the Río Bogotá (Suesca) and the Capitán Fish / Exposição a praguicidas nos habitantes da ribeira do rio Bogotá (Suesca) e no peixe "Capitán de la sabana"

Objetivo: considerando el elevado uso de plaguicidas en Colombia y los efectos nocivos que produce la exposición a estas sustancias para la salud humana y el ambiente, se realizó un estudio para la determinación de biomarcadores de exposición y efecto de plaguicidas en la población de Suesca que habita en la ribera del río Bogotá, de los niveles de plaguicidas en muestras de agua del río tomadas en el mismo municipio y en muestras de pez "Capitán de la sabana" (Eremophylus mutisii) capturado en dicha zona. Materiales y métodos: se realizaron determinaciones para organofosforados, carbamatos, ditiocarbamatos y organoclorados También se exploró, mediante una encuesta, la exposición ocupacional a plaguicidas y el conocimiento y utilización de medidas de protección personal en su actividad laboral. Adicionalmente, se examinó el hábito de la pesca de pez Capitán y su consumo en la dieta de los habitantes de esta zona del río. Resultados: los resultados muestran la presencia de plaguicidas organoclorados y organofosforados en el río y en el tejido de los peces y organoclorados y etilentiourea en las muestras biológicas humanas. En el estudio participaron trabajadores directamente expuestos a plaguicidas, quienes manipulan productos de alta toxicidad; en su mayoría conocen y emplean las medidas de protección personal e higiene industrial. Conclusiones: existe contaminación por plaguicidas en la cuenca alta del río Bogotá que afecta a la fauna y a las poblaciones ribereñas. Es necesario promover mejores medidas para el cuidado del ambiente, para la protección y para el autocuidado de las personas que manipulan plaguicidas en la zona.

Objective: Considering the high use of pesticides in Colombia and the harmful effects resulting from exposure to these substances on human health and the environment, a study for the determination of biomarkers of exposure and effect of pesticides in population of the banks of the Río Bogotá in Suesca, the levels of pesticides in river water samples taken in the same city and in samples of fish, "Capitán de la Sabana" (Eremophylus mutisii) caught in this area. Materials and methods: We measured for organophosphates, carbamates, dithiocarbamates and organochlorines. We also explored through a survey of occupational exposure to pesticides in the population and knowledge and use of personal protective measures in their work. Additionally, we explored the habit of fishing for captain and consumption in the diet of the inhabitants of the riverbank. Results: The results show the presence of organochlorine and organophosphorus pesticides in the river and in fish tissue and organochlorine and ethylene thiourea in human biological samples. Participated in the study workers directly exposed to pesticides, highly toxic handlers, most know and use personal protective measures and industrial hygiene. Conclusions: Pollution such as pesticides in the upper basin of Bogotá that affects wildlife and coastal populations. Best action is necessary to promote environmental care, protection and self-care of persons using pesticides in the area.

Objetivos: Considerando o elevado uso de praguicidas na Colômbia e os efeitos nocivos que produz a exposição a estas sustancias para a saúde humana e o ambiente, se realizou um estudo para a determinação de biomarcadores de exposição e efeito de praguicidas na população de Suesca que habita na ribeira do rio Bogotá, dos níveis de praguicidas em amostras de água do rio tomadas no mesmo município e em amostras do peixe "Capitan de la sabana" (Eremophylus mutisii) caçado nesta zona. Materiais e métodos: se realizaram determinações para organofosforados, carbamates, ditiocarbamatos e organoclorados. Também explorou-se, mediante uma pesquisa, a exposição ocupacional a praguicidas e o conhecimento e utilização de medidas de proteção pessoal em sua atividade laboral. Adicionalmente, examinou-se o hábito da pesca de peixe "Capitan de la sabana" e seu consumo na dieta dos habitantes desta zona do rio. Resultados: os resultados mostram a presencia de praguicidas organoclorados e organofosforados no rio e no tecido dos peixes e organoclorados e etilentiouréia nas amostras biológicas humanas. No estudo participaram trabalhadores diretamente expostos a praguicidas, os quais manipulam produtos de alta toxicidade; na sua maioria conhecem e empregam as medidas de proteção pessoal e higiene industrial. Conclusões: existe contaminação por praguicidas na bacia alta do rio Bogotá que afeita à fauna e às populações da ribeira. É necessário promover melhores medidas para o cuidado do ambiente, para a proteção e para o autocuidado das pessoas que manipulam praguicidas na zona.

Determinación de algunos aspectos hematológicos de Oncorhynchus mykiss (Salmonidae), en Cundinamarca, Colombia / Determination of some hematological aspects of Oncorhynchus mykiss (Salmonidae), in Cundinamarca, Columbia

Thirty-five normal, adult specimens of the rainbow trout Oncorhynchus mykiss (Richardson, 1836) cultured in the Neusa Fishculture Station (73 degrees 38'28r W; 5 degrees 8'30r N) were studied to establish normal blood values; the hematopoietic tissues (pronefros, spleen and thymus), and other organs such as the stomach were also structurally studied. The rainbow trout collected in the second half of 1990 and the beginning of the first half of 1991 had 1,415,000 erythrocytes and 22,000 leukocytes per mm3 of blood. Their hemoglobin concentration was 6.99 g/100ml. They had three types of circulating leukocytes: lymphorytes 65 per cent, polimorphonuclears 24 per cent and monocytes 11 per cent. The pronephros is the major hematopoietic organ in the rainbow trout. It produces mainly the polimorphonuclears; the spleen and the thymus are linfopoietics. The study of the hemocytometric values in the peripheral blood frotis and the structure of the hematopoietic organs of the rainbow trout is very useful, accessible and inexpensive. It produces data which yield information about physiological and pathological conditions