69 research outputs found

    Listeria monocytogenes Infection in Macrophages Induces Vacuolar-Dependent Host miRNA Response

    Get PDF
    Listeria monocytogenes is a Gram-positive facultative intracellular pathogen, causing serious illness in immunocompromised individuals and pregnant women. Upon detection by macrophages, which are key players of the innate immune response against infection, L. monocytogenes induces specific host cell responses which need to be tightly controlled at transcriptional and post-transcriptional levels. Here, we ask whether and how host miRNAs, which represent an important mechanism of post-transcriptional regulation in a wide array of biological processes, are altered by a model pathogen upon live infection of murine bone marrow derived macrophages. We first report that L. monocytogenes subverts the host genome-wide miRNA profile of macrophages in vitro. Specifically, we show that miR-155, miR-146a, miR-125a-3p/5p and miR-149 were amongst the most significantly regulated miRNAs in infected macrophages. Strikingly, these miRNAs were highly upregulated upon infection with the Listeriolysin-deficient L. monocytogenes mutant Δhly, that cannot escape from the phagosome thus representing a vacuolar-contained infection. The vacuolar miRNA response was significantly reduced in macrophages deficient for MyD88. In addition, miR-146a and miR-125a-3p/5p were regulated at transcriptional levels upon infection, and miR-125a-3p/5p were found to be TLR2 responsive. Furthermore, miR-155 transactivation in infection was regulated by NF-ÎșB p65, while miR-146a and miR-125a-3p/5p expression was unaffected in p65-deficient primary macrophages upon L. monocytogenes infection. Our results demonstrate that L. monocytogenes promotes significant changes in the miRNA expression profile in macrophages, and reveal a vacuolar-dependent miRNA signature, listeriolysin-independent and MyD88-dependent. These miRNAs are predicted to target immune genes and are therefore most likely involved in regulation of the macrophage innate immune response against infection at post-transcriptional levels

    Technical Note on the quality of DNA sequencing for the molecular characterisation of genetically modified plants

    Get PDF
    As part of the risk assessment (RA) requirements for genetically modified (GM) plants, according to Regulation (EU) No 503/2013 and the EFSA guidance on the RA of food and feed from GM plants (EFSA GMO Panel 2011), applicants need to perform a molecular characterisation of the DNA sequences inserted in the GM plant genome. This Technical Note to the applicants puts together requirements and recommendations for the quality assessment of the methodology, analysis and reporting when DNA sequencing is used for the molecular characterisation of GM plants. In particular, it applies to the use of Sanger sequencing and next-generation sequencing for the characterisation of the inserted genetic material and its flanking regions at each insertion site, the determination of the copy number of all detectable inserts and the analysis of the genetic stability of the inserts. This updated document replaces the EFSA 2018 Technical Note and reflects the current knowledge in scientific-technical methods for generating and verifying, in a standardised manner, DNA sequencing data in the context of RA of GM plants. It does not take into consideration the verification and validation of the detection method which remains under the remit of the Joint Research Centre (JRC)

    Technical Note on the quality of DNA sequencing for the molecular characterisation of genetically modified plants

    Get PDF
    As part of the risk assessment (RA) requirements for genetically modified (GM) plants, according to Regulation (EU) No 503/2013 and the EFSA guidance on the RA of food and feed from GM plants (EFSA GMO Panel, 2011), applicants need to perform a molecular characterisation of the DNA sequences inserted in the GM plant genome. The European Commission has mandated EFSA to develop a technical note to the applicants on, and checking of, the quality of the methodology, analysis and reporting covering complete sequencing of the insert and flanking regions, insertion site analysis of the GM event, and generational stability and integrity. This Technical Note puts together requirements and recommendations for when DNA sequencing is part of the molecular characterisation of GM plants, in particular for the characterisation of the inserted genetic material at each insertion site and flanking regions, the determination of the copy number of all detectable inserts, and the analysis of the genetic stability of the inserts, when addressed by Sanger sequencing or NGS. This document reflects the current knowledge in scientific‐technical methods for generating and verifying, in a standardised manner, DNA sequencing data in the context of RA of GM plants. From 1 October 2018, this Technical Note will replace the JRC guideline of 2016 (updated April 2017) related to the verification and quality assessment of the sequencing of the insert(s) and flanking regions. It does not take into consideration the verification and validation of the detection method which remains under the remit of the JRC

    Assessment of genetically modified maize MON 89034 × 1507 × MON 88017 × 59122 × DAS‐40278‐9 and subcombinations independently of their origin for food and feed uses, import and processing under Regulation (EC) No 1829/2003 (application EFSA‐GMO‐NL‐2013‐113)

    Get PDF
    Maize MON 89034 × 1507 × MON 88017 × 59122 × DAS‐40278‐9 (five‐event stack maize) was produced by conventional crossing to combine five single events: MON 89034, 1507, MON 88017, 59122 and DAS‐40278‐9. The GMO Panel previously assessed the 5 single maize events and 11 of their subcombinations and did not identify safety concerns. No new data on the single maize events or their 11 subcombinations that could modify the original conclusions on their safety were identified. The molecular characterisation, comparative analysis (agronomic, phenotypic and compositional characteristics) and the outcome of the toxicological, allergenicity and nutritional assessment indicates that the combination of the single maize events and of the newly expressed proteins in the five‐event stack maize does not give rise to food and feed safety and nutritional concerns. The GMO Panel concludes that the five‐event stack maize, as described in this application, is as safe as and nutritionally equivalent to its non‐GM comparator and the non‐GM reference varieties tested. In the case of accidental release of the five‐event stack maize into the environment, this would not raise environmental safety concerns. The GMO Panel assessed the likelihood of interactions among the single events in the 14 maize subcombinations for which no experimental data were provided, and concludes that they are expected to be as safe as and nutritionally equivalent to the single events, the previously assessed subcombinations and the five‐event stack maize. The post‐market environmental monitoring plan and reporting intervals are in line with the intended uses of the five‐event stack maize. No post‐market monitoring of food/feed is considered necessary. The GMO Panel concludes that the five‐event stack maize and its subcombinations are as safe as its non‐GM comparator and the tested non‐GM reference varieties with respect to potential effects on human and animal health and the environment

    Assessment of genetically modified soybean MON 87751 for food and feed uses under Regulation (EC) No 1829/2003 (application EFSA‐GMO‐NL‐2014‐121)

    Get PDF
    Soybean MON87751 was developed through Agrobacterium tumefaciens-mediated transformation to provide protection certain specific lepidopteran pests by the expression of the Cry1A.105 and Cry2Ab2 proteins derived from Bacillus thuringiensis. The molecular characterisation data and bioinformatic analyses did not identify issues requiring assessment for food and feed safety. None of the compositional, agronomic and phenotypic differences identified between soybean MON87751 and the conventional counterpart required further assessment. The GMO Paneldid not identify safety concerns regarding the toxicity and allergenicity of the Cry1A.105 and Cry2Ab2 proteins as expressed in soybean MON87751, and found no evidence that the genetic modification might significantly change the overall allergenicity of soybean MON87751. The nutritional impact of soybean MON87751-derived food and feed is expected to be the same as those derived from the conventional counterpart and non-GM commercial reference varieties. The GMO Panelconcludes that soybean MON87751, as described in this application, is nutritionally equivalent to and as safe as the conventional counterpart and the non-GM soybean reference varieties tested, and no post-market monitoring of food and feed is considered necessary. In the case of accidental release of viable soybean MON87751 seeds into the environment, soybean MON87751 would not raise environmental safety concerns. The post-market environmental monitoring plan and reporting intervals are in line with the intended uses of soybean MON87751. In conclusion, soybean MON87751, as described in this application, is as safe as its conventional counterpart and the tested non-GM soybean reference varieties with respect to potential effects on human and animal health and the environment

    Assessment of genetically modified maize DP4114 × MON 89034 × MON 87411 × DAS‐40278‐9 and subcombinations, for food and feed uses, under Regulation (EC) No 1829/2003 (application EFSA GMO‐NL‐2020‐171)

    Get PDF
    Genetically modified maize DP4114 × MON 89034 × MON 87411 × DAS-40278-9 was developed by crossing to combine four single events: DP4114, MON 89034, MON 87411 and DAS-40278-9. The GMO Panel previously assessed the four single maize events and two of the subcombinations and did not identify safety concerns. No new data on the single maize events or the assessed subcombinations were identified that could lead to modification of the original conclusions on their safety. The molecular characterisation, comparative analysis (agronomic, phenotypic and compositional characteristics) and the outcome of the toxicological, allergenicity and nutritional assessment indicate that the combination of the single maize events and of the newly expressed proteins in the four-event stack maize does not give rise to food and feed safety and nutritional concerns. Therefore, no post-market monitoring of food/feed is considered necessary. In the case of accidental release of viable four-event stack maize grains into the environment, this would not raise environmental safety concerns. The GMO Panel assessed the likelihood of interactions among the single events in eight of the maize subcombinations not previously assessed and concludes that these are expected to be as safe as the single events, the previously assessed subcombinations and the four-event stack maize. The post-market environmental monitoring plan and reporting intervals are in line with the intended uses of maize DP4114 × MON 89034 × MON 87411 × DAS-40278-9. Post-market monitoring of food/feed is not considered necessary. The GMO Panel concludes that the four-event stack maize and its subcombinations are as safe as its non-GM comparator and the tested non-GM maize varieties with respect to potential effects on human and animal health and the environment

    Assessment of genetically modified maize 1507 × MIR162 × MON810 × NK603 and subcombinations, for food and feed uses, under Regulation (EC) No 1829/2003 (application EFSA-GMO-NL-2015-127).

    Get PDF
    Maize 1507 × MIR162 × MON810 × NK603 (four-event stack maize) was produced by conventional crossing to combine four single events: 1507, MIR162, MON810 and NK603. The GMO Panel previously assessed the four single events and six of the subcombinations and did not identify safety concerns. No new data on the single events or the six subcombinations that could lead to modification of the original conclusions on their safety were identified. The molecular characterisation, comparative analysis (agronomic, phenotypic and compositional characteristics) and the outcome of the toxicological, allergenicity and nutritional assessment indicate that the combination of the single maize events and of the newly expressed proteins in the four-event stack maize does not give rise to food and feed safety and nutritional concerns. The GMO Panel concludes that the four-event stack maize, as described in this application, is as safe as its non-GM comparator and the non-GM reference varieties tested. In the case of accidental release of viable seeds of the four-event stack maize into the environment, this would not raise environmental safety concerns. The GMO Panel assessed the likelihood of interactions among the single events in the four maize subcombinations not previously assessed and concludes that these are expected to be as safe as the single events, the previously assessed subcombinations and the four-event stack maize. The post-market environmental monitoring plan and reporting intervals are in line with the intended uses of the four-event stack maize. Post-market monitoring of food/feed is not considered necessary. The GMO Panel concludes that the four-event stack maize and its subcombinations are as safe as the non-GM comparator and the tested non-GM reference varieties with respect to potential effects on human and animal health and the environment

    Assessment of genetically modified maize MON 87419 for food and feed uses, under Regulation (EC) No 1829/2003 (application EFSA‐GMO‐NL‐2017‐140)

    Get PDF
    Genetically modified maize MON 87419 was developed to confer tolerance to dicamba- and glufosinate-based herbicides. These properties were achieved by introducing the dmo and pat expression cassettes. The molecular characterisation data and bioinformatic analyses do not identify issues requiring food/feed safety assessment. None of the identified differences in the agronomic/phenotypic and compositional characteristics tested between maize MON 87419 and its conventional counterpart needed further assessment, except for the levels of arginine and protein in grains which did not raise safety and nutritional concerns. The GMO Panel does not identify safety concerns regarding the toxicity and allergenicity of the dicamba mono-oxygenase (DMO) and phosphinothricin N-acetyltransferase (PAT) proteins as expressed in maize MON 87419. The GMO Panel finds no evidence that the genetic modification impacts the overall safety of maize MON 87419. In the context of this application, the consumption of food and feed from maize MON 87419 does not represent a nutritional concern in humans and animals. The GMO Panel concludes that maize MON 87419 is as safe as the conventional counterpart and non-GM maize varieties tested, and no post-market monitoring of food/feed is considered necessary. In the case of accidental release of viable maize MON 87419 grains into the environment, this would not raise environmental safety concerns. The postmarket environmental monitoring plan and reporting intervals are in line with the intended uses of maize MON 87419. The GMO Panel concludes that maize MON 87419 is as safe as its conventional counterpart and the tested non-GM maize varieties with respect to potential effects on human and animal health and the environment

    Assessment of genetically modified maize GA21 × T25 for food and feed uses, under Regulation (EC) No 1829/2003 (application EFSA‐GMO‐DE‐2016‐137)

    Get PDF
    Genetically modified maize GA21 x T25 was developed by crossing to combine two single events: GA21 and T25. The GMO Panel previously assessed the two single maize events and did not identify safety concerns. No new data on the single maize events were identified that could lead to modification of the original conclusions on their safety. The molecular characterisation, comparative analysis (agronomic, phenotypic and compositional characteristics) and the outcome of the toxicological, allergenicity and nutritional assessment indicate that the combination of the single maize events and of the newly expressed proteins in maize GA21 x T25 does not give rise to food and feed safety and nutritional concerns. The GMO Panel concludes that maize GA21 x T25, as described in this application, is as safe as its conventional counterpart and the non-GM reference varieties tested, and no post-market monitoring of food and feed is considered necessary. In the case of accidental release of viable maize GA21 x T25 grains into the environment, this would not raise environmental safety concerns. The post-market environmental monitoring plan and reporting intervals are in line with the intended uses of maize GA21 x T25. Post-market monitoring of food and feed is not considered necessary. The GMO Panel concludes that maize GA21 x T25 is as safe as its conventional counterpart and the non-GM reference varieties tested, with respect to potential effects on human and animal health and the environment
    • 

    corecore