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During infections, neutrophil extracellular traps act like a meshwork of molecules that captures microbes. In contrast, during sterile inflammation the presence of NETs is usually associated with tissue damage and uncontrolled inflammation. In this context, DNA acts both as activator of NETs formation and immunogenic molecule fueling inflammation within the injured tissue microenvironment. Pattern recognition receptors that specifically bind to and get activated by DNA such as Toll-like receptor-9 (TLR9), cyclic GMP-AMP synthase (cGAS), Nod-like receptor protein 3 (NLRP3) and Absence in Melanoma-2 (AIM2) have been reported to play a role in NETs formation and detection. However, how these DNA sensors contribute to NETs-driven inflammation is not well understood. Whether these DNA sensors have unique roles or on the contrary they are mostly redundant is still elusive. In this review, we summarize the known contribution of the above DNA sensors to the formation and detection of NETs in the context of sterile inflammation. We also highlight scientific gaps needed to be addressed and propose future direction for therapeutic targets.

ABSTRACT Cytoplasmic detection of DNA by cyclic GMP-AMP (cGAMP) synthase (cGAS) is an essential component of antiviral responses. Upon synthesis, cGAMP binds to the stimulator of interferon (IFN) genes (STING) in infected and adjacent cells through intercellular transfer by connexins forming gap-junctions, eliciting a strong IFN-β-driven antiviral response. We demonstrate here that Genistein, a flavonoid compound naturally occurring in soy-based foods, inhibits cGAS-STING antiviral signaling at two levels. First, Genistein pretreatment of cGAMP-producing cells inhibited gap-junction intercellular communication, resulting in reduced STING responses in adjacent cells. In addition, Genistein directly blocked STING activation by the murine agonist DMXAA, by decreasing the interaction of STING with TBK1 and IKKε. As a result, Genistein attenuated STING signaling in human and mouse cells, dampening antiviral activity against Semliki Forest Virus infection. Collectively, our findings identify a previously unrecognized proviral activity of Genistein mediated via its inhibitory effects at two levels of cGAS-STING signaling. IMPORTANCE Several reports suggest that Genistein exhibits antiviral activities against DNA viruses. Our work uncovers a previously unrecognized proviral effect of Genistein, through inhibition of the cGAS-STING pathway at the level of cGAMP transfer and its sensing by STING. This suggests that the use of Genistein as an antiviral should be taken with caution as it may reduce the protective antiviral effects elicited by host STING activation.

Mitochondrial content in extracellular vesicles (EVs) can enhance inflammation, although its role in noninflammatory conditions is unclear. Here, the authors show that mitochondria-derived vesicles target material to EVs, whereas Parkin directs damaged mitochondrial content to lysosomes, providing insight into mitochondria-driven immune responses.

Fanconi Anemia (FA) is a genome instability syndrome caused by mutations in one of the 23 repair genes of the Fanconi pathway. This heterogenous disease is usually characterized by congenital abnormalities, premature ageing and bone marrow failure. FA patients also show a high predisposition to hematological and solid cancers. The Fanconi pathway ensures the repair of interstrand crosslinks (ICLs) DNA damage. Defect in one of its proteins prevents functional DNA repair, leading to the accumulation of DNA breaks and genome instability. Accumulating evidence has documented a close relationship between genome instability and inflammation, including the production of type-I Interferon. In this context, type-I Interferon is produced upon activation of pattern recognition receptors by nucleic acids including by the cyclic GMP-AMP synthase (cGAS) that detects DNA. In mouse models of diseases displaying genome instability, type-I Interferon response is responsible for an important part of the pathological symptoms, including premature aging, short stature, and neurodegeneration. This is illustrated in mouse models of Ataxia-telangiectasia and Aicardi-Goutières Syndrome in which genetic depletion of either Interferon Receptor IFNAR, cGAS or STING relieves pathological symptoms. FA is also a genetic instability syndrome with symptoms such as premature aging and predisposition to cancer. In this review we will focus on the different molecular mechanisms potentially leading to type-I Interferon activation. A better understanding of the molecular mechanisms engaging type-I Interferon signaling in FA may ultimately lead to the discovery of new therapeutic targets to rescue the pathological inflammation and premature aging associated with Fanconi Anemia.

Activation of the STING pathway upon genotoxic treatment of cancer cells has been shown to lead to anti-tumoral effects, mediated through the acute production of interferon (IFN)-β. Conversely, the pathway also correlates with the expression of NF-κB-driven pro-tumorigenic genes, but these associations are only poorly defined in the context of genotoxic treatment, and are thought to correlate with a chronic engagement of the pathway. We demonstrate here that half of the STING-expressing cancer cells from the NCI60 panel rapidly increased expression of pro-tumorigenic IL-6 upon genotoxic DNA damage, often independent of type-I IFN responses. While preferentially dependent on canonical STING, we demonstrate that genotoxic DNA damage induced by camptothecin (CPT) also drove IL-6 production through non-canonical STING signaling in selected cancer cells. Consequently, pharmacological inhibition of canonical STING failed to broadly inhibit IL-6 production induced by CPT, although this could be achieved through downstream ERK1/2 inhibition. Finally, prolonged inhibition of canonical STING signaling was associated with increased colony formation of MG-63 cells, highlighting the duality of STING signaling in also restraining the growth of selected cancer cells. Collectively, our findings demonstrate that genotoxic-induced DNA damage frequently leads to the rapid production of pro-tumorigenic IL-6 in cancer cells, independent of an IFN signature, through canonical and non-canonical STING activation; this underlines the complexity of STING engagement in human cancer cells, with frequent acute pro-tumorigenic activities induced by DNA damage. We propose that inhibition of ERK1/2 may help curb such pro-tumorigenic responses to DNA-damage, while preserving the anti-proliferative effects of the STING-interferon axis.

ABSTRACT Activation of cyclic GMP-AMP (cGAMP) synthase (cGAS) plays a critical role in antiviral responses to many DNA viruses. Sensing of cytosolic DNA by cGAS results in synthesis of the endogenous second messenger cGAMP that activates stimulator of interferon genes (STING) in infected cells. Critically, cGAMP can also propagate antiviral responses to uninfected cells through intercellular transfer, although the modalities of this transfer between epithelial and immune cells remain poorly defined. We demonstrate here that cGAMP-producing epithelial cells can transactivate STING in cocultured macrophages through direct cGAMP transfer. cGAMP transfer was reliant upon connexin expression by epithelial cells and pharmacological inhibition of connexins blunted STING-dependent transactivation of the macrophage compartment. Macrophage transactivation by cGAMP contributed to a positive-feedback loop amplifying antiviral responses, significantly protecting uninfected epithelial cells against viral infection. Collectively, our findings constitute the first direct evidence of a connexin-dependent cGAMP transfer to macrophages by epithelial cells, to amplify antiviral responses. IMPORTANCE Recent studies suggest that extracellular cGAMP can be taken up by macrophages to engage STING through several mechanisms. Our work demonstrates that connexin-dependent communication between epithelial cells and macrophages plays a significant role in the amplification of antiviral responses mediated by cGAMP and suggests that pharmacological strategies aimed at modulating connexins may have therapeutic applications to control antiviral responses in humans.

Amaryllidaceae plants are rich in alkaloids with biological properties. Pancratium trianthum is an Amaryllidaceae species widely used in African folk medicine to treat several diseases such as central nervous system disorders, tumors, and microbial infections, and it is used to heal wounds. The current investigation explored the biological properties of alkaloid extracts from bulbs of P. trianthum collected in the Senegalese flora. Alkaloid extracts were analyzed and identified by chromatography and mass spectrometry. Alkaloid extracts from P. trianthum displayed pleiotropic biological properties. Cytotoxic activity of the extracts was determined on hepatocarcinoma Huh7 cells and on acute monocytic leukemia THP-1 cells, while agar diffusion and microdilution assays were used to evaluate antibacterial activity. Antiviral activity was measured by infection of extract-treated cells with dengue virus (DENVGFP) and human immunodeficiency virus-1 (HIV-1GFP) reporter vectors. Cytotoxicity and viral inhibition were the most striking of P. trianthum’s extract activities. Importantly, non-cytotoxic concentrations were highly effective in completely preventing DENVGFP replication and in reducing pseudotyped HIV-1GFP infection levels. Our results show that P. trianthum is a rich source of molecules for the potential discovery of new treatments against various diseases. Herein, we provide scientific evidence to rationalize the traditional uses of P. trianthum for wound treatment as an anti-dermatosis and antiseptic agent.

Murine models of Salmonella enterica serovar Typhimurium infection are one of the commonest tools to study host-pathogen interactions during bacterial infections. Critically, the outcome of S. Typhimurium infection is impacted by the genetic background of the mouse strain used, with macrophages from C57BL/6 and BALB/c mice lacking the capacity to control intracellular bacterial replication. For this reason, the use of congenic strains, which mix the genetic backgrounds of naturally protected mouse strains with those of susceptible strains, has the capacity to significantly alter results and interpretation of S. Typhimurium infection studies. Here, we describe how macrophage knockout cell lines generated by CRISPR/Cas9 gene editing can help determine the contribution of background contaminations in the phenotypes of primary macrophages from congenic mice, on the outcome of S. Typhimurium infection studies. Our own experience illustrates how the CRISPR/Cas9 technology can be used to complement pre-existing knockout models, and shows that there is great merit in performing concurrent studies with both genetic models, to exclude unanticipated side-effects on host-pathogen interactions.

MicroRNA (miRNA) detection by reverse transcription (RT) quantitative real-time PCR (RT-qPCR) is the most popular method currently used to measure miRNA expression. Although the majority of miRNA families are constituted of several 3′-end length variants (“isomiRs”), little attention has been paid to their differential detection by RT-qPCR. However, recent evidence indicates that 3′-end miRNA isoforms can exhibit 3′-length specific regulatory functions, underlining the need to develop strategies to differentiate 3′-isomiRs by RT-qPCR approaches. We demonstrate here that polyadenylation-based RT-qPCR strategies targeted to 20–21 nt isoforms amplify entire miRNA families, but that primers targeted to >22 nt isoforms were specific to >21 nt isoforms. Based on this observation, we developed a simple method to increase selectivity of polyadenylation-based RT-qPCR assays toward shorter isoforms, and demonstrate its capacity to help distinguish short RNAs from longer ones, using synthetic RNAs and biological samples with altered isomiR stoichiometry. Our approach can be adapted to many polyadenylation-based RT-qPCR technologies already exiting, providing a convenient way to distinguish long and short 3′-isomiRs.

ABSTRACT Inflammatory responses, while essential for pathogen clearance, can also be deleterious to the host. Chemical inhibition of topoisomerase 1 (Top1) by low-dose camptothecin (CPT) can suppress transcriptional induction of antiviral and inflammatory genes and protect animals from excessive and damaging inflammatory responses. We describe the unexpected finding that minor DNA damage from topoisomerase 1 inhibition with low-dose CPT can trigger a strong antiviral immune response through cyclic GMP-AMP synthase (cGAS) detection of cytoplasmic DNA. This argues against CPT having only anti-inflammatory activity. Furthermore, expression of the simian virus 40 (SV40) large T antigen was paramount to the proinflammatory antiviral activity of CPT, as it potentiated cytoplasmic DNA leakage and subsequent cGAS recruitment in human and mouse cell lines. This work suggests that the capacity of Top1 inhibitors to blunt inflammatory responses can be counteracted by viral oncogenes and that this should be taken into account for their therapeutic development. IMPORTANCE Recent studies suggest that low-dose DNA-damaging compounds traditionally used in cancer therapy can have opposite effects on antiviral responses, either suppressing (with the example of CPT) or potentiating (with the example of doxorubicin) them. Our work demonstrates that the minor DNA damage promoted by low-dose CPT can also trigger strong antiviral responses, dependent on the presence of viral oncogenes. Taken together, these results call for caution in the therapeutic use of low-dose chemotherapy agents to modulate antiviral responses in humans.

This article reports on the evidence for mental health occupational therapy in peer-reviewed journals from 2000 to 2013. Descriptive and inductive methods were used to address this question, with evidence from CINAHL, OTDBase, PSYCInfo, SCOPUS, and Google Scholar® included. Many articles ( n = 1,747) were found that met the inclusion and exclusion criteria. A total of 47 different methods were used to develop evidence for mental health occupational therapy, and evidence appeared in 300 separate peer-reviewed journals. It takes on average 7 months for an article to progress from submission to acceptance, and a further 7 months to progress from acceptance to publication. More than 95% of articles published between 2000 and 2002 were cited at least once in the following decade, and around 70% of these citations were recorded in non-occupational therapy journals. The current evidence base for mental health occupational therapy is both substantial and diverse.

The ribonuclease Dicer plays a central role in the microRNA pathway by processing microRNA precursors (pre-microRNAs) into microRNAs, a class of 19- to 24-nucleotide non-coding RNAs that regulate expression of ≈60% of the genes in humans. To gain further insights into the function and regulation of Dicer in human cells, we performed a yeast two-hybrid (Y2HB) screen using human Dicer double-stranded RNA-binding domain (dsRBD) as bait. This approach identified tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK) as a Dicer-interacting protein candidate. Confocal immunofluorescence microscopy revealed the colocalization of Dicer and TWEAK proteins at the perinuclear region of HeLa cells. The Dicer-TWEAK protein interaction was confirmed by coimmunoprecipitation and found not likely to be mediated by RNA. TWEAK dose-dependently reduced pre-microRNA conversion into mature microRNA in Dicer activity assays using extracts of transfected human HEK 293 cells. TWEAK expression also impaired microRNA-guided RNA silencing of a reporter gene induced by a pre-microRNA. These findings suggest a role for TWEAK—a pro-inflammatory cytokine—in regulating Dicer function and microRNA biogenesis, and its possible involvement in regulating gene expression during inflammatory processes and diseases.

Cet article présente deux modèles conceptuels dont la combinaison est utilisée dans le domaine de l’évaluation. Dans un premier temps, les deux modèles seront décrits, leur arrimage expliqué ainsi que les effets de leur utilisation sur l’investissement des différents partenaires concernés. Ensuite, des exemples de démarches évaluatives auxquelles la combinaison des modèles conceptuels a été appliquée seront présentés. Ces exemples mettront en lumière les avantages de l’utilisation de cette combinaison sur le développement, la mise en oeuvre, la pérennité et l’efficacité d’un programme ou d’une démarche évaluative, et ce, indépendamment du contexte d’implantation.

There is a growing appreciation that the direct interaction between bacteriophages and the mammalian host can facilitate diverse and unexplored symbioses. Yet the impact these bacteriophages may have on mammalian cellular and immunological processes is poorly understood. Here, we applied highly purified phage T4, free from bacterial by-products and endotoxins to mammalian cells and analyzed the cellular responses using luciferase reporter and antibody microarray assays. Phage preparations were applied in vitro to either A549 lung epithelial cells, MDCK-I kidney cells, or primary mouse bone marrow derived macrophages with the phage-free supernatant serving as a comparative control. Highly purified T4 phages were rapidly internalized by mammalian cells and accumulated within macropinosomes but did not activate the inflammatory DNA response TLR9 or cGAS-STING pathways. Following 8 hours of incubation with T4 phage, whole cell lysates were analyzed via antibody microarray that detected expression and phosphorylation levels of human signaling proteins. T4 phage application led to the activation of AKT-dependent pathways, resulting in an increase in cell metabolism, survival, and actin reorganization, the last being critical for macropinocytosis and potentially regulating a positive feedback loop to drive further phage internalization. T4 phages additionally down-regulated CDK1 and its downstream effectors, leading to an inhibition of cell cycle progression and an increase in cellular growth through a prolonged G1 phase. These interactions demonstrate that highly purified T4 phages do not activate DNA-mediated inflammatory pathways but do trigger protein phosphorylation cascades that promote cellular growth and survival. We conclude that mammalian cells are internalizing bacteriophages as a resource to promote cellular growth and metabolism.

Plain English Summary The mortality rate of eating disorders is significantly elevated compared to other psychiatric conditions, primarily due to medical complications and suicide. Further, individuals with eating disorders often meet the diagnostic criteria of at least one comorbid psychiatric or medical disorder, that is, the individual simultaneously experiences both an ED and at least one other condition. This has significant consequences for researchers and health care providers – medical and psychiatric comorbidities impact ED symptoms and treatment effectiveness. The current review is part of a larger Rapid Review series conducted to inform the development of Australia’s National Eating Disorders Research and Translation Strategy 2021–2031. A Rapid Review is designed to comprehensively summarise a body of literature in a short timeframe, often to guide policymaking and address urgent health concerns. The Rapid Review synthesises the current evidence base and identifies gaps in eating disorder research and care. This paper gives a critical overview of the scientific literature relating to the psychiatric and medical comorbidities of eating disorders. It covers recent literature regarding psychiatric comorbidities including anxiety disorders, mood disorders, substance use disorders, trauma and personality disorders and neurodevelopmental disorders. Further, the review discusses the impact and associations between EDs and medical comorbidities, some of which precede the eating disorder, occur alongside, or as a consequence of the eating disorder.

Background While evidence-based practice is a familiar concept to allied health clinicians, knowledge translation (KT) is less well known and understood. The need for a framework that enables allied health clinicians to access and engage with KT was identified. The aim of this paper is to describe the development of the Translating Allied Health Knowledge (TAHK) Framework. Methods An iterative and collaborative process involving clinician and academic knowledge partners was utilised to develop the TAHK Framework. Multiple methods were utilised during this process, including a systematic literature review, steering committee consultation, mixed methods survey, benchmarking and measurement property analysis. Results The TAHK Framework has now been finalised, and is described in detail. The framework is structured around four domains – Doing Knowledge Translation, Social Capital for Knowledge Translation, Sustaining Knowledge Translation and Inclusive Knowledge Translation – under which 14 factors known to influence allied health KT are classified. The formulation of the framework to date has laid a rigorous foundation for further developments, including clinician support and outcome measurement. Conclusion The method of development adopted for the TAHK Framework has ensured it is both evidence and practice based, and further amendments and modifications are anticipated as new knowledge becomes available. The Framework will enable allied health clinicians to build on their existing capacities for KT, and approach this complex process in a rigorous and systematic manner. The TAHK Framework offers a unique focus on how knowledge is translated by allied health clinicians in multidisciplinary settings.

Abstract Background In 2014, a large metropolitan mental health service in Australia developed a senior role (Lead Research Occupational Therapist) to address an identified need for greater research and knowledge translation, and associated capacity building. The aim of this study was to evaluate the impact, in the first 2.5 years, of this role across a range of variables. Methods Multiple methods were used to gather a comprehensive range of data. Workforce surveys were completed both online and in hard copy in early 2014 (n = 42) and late 2016 (n = 44). Research key performance indicators (academic, research production and cultural) were also identified for measurement over time. The data from these surveys were analysed using descriptive and inductive analysis, and also with social network analysis. Results This role has demonstrated positive outcomes across a range of variables. There was a medium effect on the quantity of participation in quality assurance and knowledge translation activities by the workforce. Most knowledge translation behaviours were occurring regularly, although several were absent. An improving trend in attitudes towards evidence-based practice was recorded, and perceptions of the knowledge translation role were generally positive. The Lead Research Occupational Therapist moved from the periphery to the centre of the evidence based practice social network. Improved awareness of other clinicians deploying evidence based practice was observed, and the frequency of interaction between clinicians increased. The role has met all key performance indicators, across the academic, research production and cultural domains. Conclusions The shift in focus of this role from research to knowledge translation has produced tangible outcomes for the occupational therapy workforce. These achievements have had a positive impact on the sustainability of the role, which will be continued for at least another two years. An ongoing challenge is to directly measure the impact of this role on outcomes for people with mental illness and their carers.

ObjectiveTo examine the health care costs associated with mental disorders and subthreshold mental disorders within a nationally representative sample of children and adolescents in Australia.MethodData were derived from the Young Minds Matter Survey (N = 6,310). Mental disorders were classified using the Diagnostic Interview Schedule for Children Version IV. Participant data were linked to administrative data on health care costs. Adjusted generalized linear regression models and two-part models were used to estimate mean differences in costs between those with a mental disorder or subthreshold disorder and those without.ResultsCosts associated with health care attendances and medications were higher for children and adolescents with mental disorders and subthreshold mental disorders compared to those without a mental disorder. The additional population health care costs due to mental disorders amounted to AUD$234 million annually in children and adolescents, of which approximately 16% was attributed to out-of-pocket costs. Findings showed that those with subthreshold mental disorders or comorbid mental disorders have substantial additional costs of Medicare-funded medical and pharmaceutical services.Conclusion and implicationMental disorders in children and adolescents are associated with significant health care costs. Further research is needed to ensure that this population is receiving effective and efficient care.