Use of elemental profiles determined by energy-dispersive X-ray fluorescence and multivariate analyses to detect adulteration in Ceylon cinnamon.

The price of Cinnamomum verum (Ceylon cinnamon) is around twice as high as that of the other cinnamon varieties commonly grouped under the name cassia cinnamon, making the former spice an attractive target for fraudsters. This work demonstrates that elemental profiles obtained by energy-dispersive X-ray fluorescence in combination with multivariate analyses can be used as a screening method to detect Ceylon cinnamon adulteration. Thirty-six elements were analysed in 52 commercially available cinnamon samples, 29 Ceylon, 8 cassia, and 15 for which no indication about variety was provided. Fifty-eight percent of the samples were either adulterated or did not meet international quality criteria. Four of the ground cinnamon samples labelled as Ceylon cinnamon were found to be pure cassia or a mixture with a high cassia content, and 26 samples were suspected of other types of adulteration including replacement of bark with other parts of the cinnamon tree. Headspace gas chromatography-mass spectrometry and ash determination by thermogravimetric analysis confirmed the conclusions reached by elemental analysis. Only one sample labelled as Ceylon cinnamon and that according to its volatile composition was cassia cinnamon was not flagged as suspicious by elemental analysis.

Detection and Quantification of Botanical Impurities in Commercial Oregano (Origanum vulgare) Using Metabarcoding and Digital PCR.

DNA technology for food authentication is already well established, and with the advent of Next Generation Sequencing (NGS) and, more specifically, metabarcoding, compositional analysis of food at the molecular level has rapidly gained popularity. This has led to several reports in the media about the presence of foreign, non-declared species in several food commodities. As herbs and spices are attractive targets for fraudulent manipulation, a combination of digital PCR and metabarcoding by NGS was employed to check the purity of 285 oregano samples taken from the European market. By using novel primers and analytical approaches, it was possible to detect and quantify both adulterants and contaminants in these samples. The results highlight the high potential of NGS for compositional analysis, although its quantitative information (read count percentages) is unreliable, and other techniques are therefore needed to complement the sequencing information for assessing authenticity ('true to the name') of food ingredients.

DNA Accounting: Tallying Genomes to Detect Adulterated Saffron.

The EU General Food Law not only aims at ensuring food safety but also to 'prevent fraudulent or deceptive practices; the adulteration of food; and any other practices which may mislead the consumer'. Especially the partial or complete, deliberate, and intentional substitution of valuable ingredients (e.g., Saffron) for less valuable ones is of concern. Due to the variety of products on the market an approach to detect food adulteration that works well for one species may not be easily applicable to another. Here we present a broadly applicable approach for the detection of substitution of biological materials based on digital PCR. By simultaneously measuring and forecasting the number of genome copies in a sample, fraud is detectable as a discrepancy between these two values. Apart from the choice of target gene, the procedure is identical across all species. It is scalable, rapid, and has a high dynamic range. We provide proof of concept by presenting the analysis of 141 samples of Saffron (Crocus sativus) from across the European market by DNA accounting and the verification of these results by NGS analysis.

The EU one-stop-shop collection of publicly available information on COVID-19 in vitro diagnostic medical devices.

The JRC COVID-19 In Vitro Diagnostic Devices and Test Methods Database, aimed to collect in a single place all publicly available information on performance of CE-marked in vitro diagnostic medical devices (IVDs) as well as in house laboratory-developed devices and related test methods for COVID-19, is here presented. The database, manually curated and regularly updated, has been developed as a follow-up to the Communication from the European Commission "Guidelines on in vitro diagnostic tests and their performance" of 15 April 2020 and is freely accessible at https://covid-19-diagnostics.jrc.ec.europa.eu/.

C-type lectin receptor DCIR modulates immunity to tuberculosis by sustaining type I interferon signaling in dendritic cells.

Immune response against pathogens is a tightly regulated process that must ensure microbial control while preserving integrity of the infected organs. Tuberculosis (TB) is a paramount example of a chronic infection in which antimicrobial immunity is protective in the vast majority of infected individuals but can become detrimental if not finely tuned. Here, we report that C-type lectin dendritic cell (DC) immunoreceptor (DCIR), a key component in DC homeostasis, is required to modulate lung inflammation and bacterial burden in TB. DCIR is abundantly expressed in pulmonary lesions in Mycobacterium tuberculosis-infected nonhuman primates during both latent and active disease. In mice, we found that DCIR deficiency impairs STAT1-mediated type I IFN signaling in DCs, leading to increased production of IL-12 and increased differentiation of T lymphocytes toward Th1 during infection. As a consequence, DCIR-deficient mice control M. tuberculosis better than WT animals but also develop more inflammation characterized by an increased production of TNF and inducible NOS (iNOS) in the lungs. Altogether, our results reveal a pathway by which a C-type lectin modulates the equilibrium between infection-driven inflammation and pathogen's control through sustaining type I IFN signaling in DCs.

Molecular and functional characterization of Toll-like receptor (Tlr)1 and Tlr2 in common carp (Cyprinus carpio).

Toll-like receptors (TLRs) are fundamental components of innate immunity that play significant roles in the defence against pathogen invasion. In this study, we present the molecular characterization of the full-length coding sequence of tlr1, tlr2a and tlr2b from common carp (Cyprinus carpio). Each is encoded within a single exon and contains a conserved number of leucine-rich repeats, a transmembrane region and an intracellular TIR domain for signalling. Indeed, sequence, phylogenetic and synteny analysis of carp tlr1, tlr2a and tlr2b support that these genes are orthologues of mammalian TLR1 and TLR2. The tlr genes are expressed in various immune organs and cell types. Furthermore, the carp sequences exhibited a good three-dimensional fit with the heterodimer structure of human TLR1-TLR2, including the potential to bind to the ligand Pam3CSK4. This supports the possible formation of carp Tlr1-Tlr2 heterodimers. However, we were unable to demonstrate Tlr1/Tlr2-mediated ligand binding in transfected cell lines through NF-κB activation, despite showing the expression and co-localization of Tlr1 and Tlr2. We discuss possible limitations when studying ligand-specific activation of NF-κB after expression of Tlr1 and/or Tlr2 in human but also fish cell lines and we propose alternative future strategies for studying ligand-binding properties of fish Tlrs.

Carp Il10 Has Anti-Inflammatory Activities on Phagocytes, Promotes Proliferation of Memory T Cells, and Regulates B Cell Differentiation and Antibody Secretion.

In the current study, we investigated the effects of carp Il10 on phagocytes and lymphocytes. Carp Il10 shares several prototypical inhibitory activities on phagocytes with mammalian IL-10, including deactivation of neutrophils and macrophages, as shown by inhibition of oxygen and nitrogen radical production, as well as reduced expression of proinflammatory genes and mhc genes involved in Ag presentation. Similar to mammalian IL-10, carp Il10 acts through a signaling pathway involving phosphorylation of Stat3, ultimately leading to the early upregulation of socs3 expression. To our knowledge, this is the first study of the effects of Il10 on lymphocytes in fish. Although Il10 did not affect survival and proliferation of T cells from naive animals, it greatly promoted survival and proliferation of T cells in cultures from immunized animals, but only when used in combination with the immunizing Ag. Preliminary gene expression analysis suggests that, under these circumstances, carp Il10 stimulates a subset of CD8+ memory T cells while downregulating CD4+ memory Th1 and Th2 responses. In addition to the regulatory effect on T cells, carp Il10 stimulates proliferation, differentiation, and Ab secretion by IgM+ B cells. Overall, carp Il10 shares several prototypical activities with mammalian IL-10, including downregulation of the inflammatory response of phagocytes, stimulation of proliferation of subsets of memory T lymphocytes, and proliferation, differentiation, and Ab secretion by IgM+ B lymphocytes. To our knowledge, this is the first comprehensive analysis of biological activities of fish Il10 on both phagocytes and lymphocytes showing functional conservation of several properties of Il10.

[A man with an abnormal dimple in his upper leg]. / Een man met een abnormale delle in zijn bovenbeen.

A 29 year-old man presented with muscle weakness and an abnormal dimple near his hamstrings after a complicated anterior cruciate ligament reconstruction of his right knee. MRI demonstrated atrophy of the semitendinosus muscle. He received physiotherapy after which he functionally recovered.

Identification and functional characterization of nonmammalian Toll-like receptor 20.

Like other vertebrate Toll-like receptors (TLRs), the TLRs of teleost fish can be subdivided into six major families, each of which recognize a general class of molecular patterns. However, there also are a number of Tlrs with unknown function, the presence of which seems unique to the bony fish, among which is Tlr20. We identified full-length complementary DNA (cDNA) sequences for tlr20 of zebrafish and common carp, two closely related fish species. Zebrafish have six copies of tlr20, whereas carp express only a single copy. Both zebrafish Tlr20 (at least Tlr20a-d) and carp Tlr20 have 26 leucine-rich repeats (LRRs). Three-dimensional modeling indicates a best fit to the crystal structure of TLR8. Phylogenetic analyses place Tlr20 in the TLR11 family closest to Tlr11 and Tlr12, which sense ligands from protozoan parasites in the mouse. Conservation of genes on zebrafish chromosome 9, which carries tlr20, with genes on mouse chromosome 14, which carries tlr11, indicates Tlr11 could be a possible ortholog of Tlr20. Confocal microscopy suggests a subcellular localization of Tlr20 at the endoplasmatic reticulum. Although in vitro reporter assays could not identify a ligand unique to Tlr20, in vivo infection experiments indicate a role for Tlr20 in the immune response of carp to protozoan parasites (Trypanoplasma borreli). Carp tlr20 is mainly expressed in peripheral blood leukocytes (PBL) with B lymphocytes, in particular, expressing relatively high levels of Tlr20. In vitro stimulation of PBL with T. borreli induces an upregulation of tlr20, supportive of a role for Tlr20 in the immune response to protozoan parasites.

Ligand specificities of Toll-like receptors in fish: indications from infection studies.

Toll like receptors (TLRs) are present in many different fish families from several different orders, including cyprinid, salmonid, perciform, pleuronectiform and gadiform representatives, with at least some conserved properties among these species. However, low conservation of the leucine-rich repeat ectodomain hinders predictions of ligand specificities of fish TLRs based on sequence information only. We review the presence of a TLR genes, and changes in their gene expression profiles as result of infection, in the context of different fish orders and fish families. The application of RT-qPCR and availability of increasing numbers of fish genomes has led to numerous gene expression studies, including studies on TLR gene expression, providing the most complete dataset to date. Induced changes of gene expression may provide (in)direct evidence for the involvement of a particular TLR in the reaction to a pathogen. Especially when findings are consistent across different studies on the same fish species or consistent across different fish species, up-regulation of TLR gene expression could be a first indication of functional relevance. We discuss TLR1, TLR2, TLR4, TLR5 and TLR9 as presumed sensors of bacterial ligands and discuss as presumed sensors of viral ligands TLR3 and TLR22, TLR7 and TLR8. More functional studies are needed before conclusions on ligands specific to (groups of) fish TLRs can be drawn, certainly true for studies on non-mammalian TLRs. Future studies on the conservation of function of accessory molecules, in conjunction with TLR molecules, may bring new insight into the function of fish TLRs.

ß-Glucan-supplemented diets increase poly(I:C)-induced gene expression of Mx, possibly via Tlr3-mediated recognition mechanism in common carp (Cyprinus carpio).

We have previously observed that in common carp (Cyprinus carpio), administration of ß-glucan (MacroGard®) as feed additive leads to a lower expression of pro-inflammatory cytokines suggesting that this immunostimulant may be preventing an acute and potentially dangerous response to infection, particularly in the gut. However, in general, mechanisms to detect and eliminate pathogens must also be induced in order to achieve an efficient clearance of the infection. Protection against viral diseases acquired through ß-glucan-supplemented feed has been extensively reported for several experimental models in fish but the underlining mechanisms are still unknown. Thus, in order to better characterize the antiviral action induced by ß-glucans in fish, MacroGard® was administered daily to common carp in the form of supplemented commercial food pellets. Carp were fed for a period of 25 days prior to intra-peritoneal injection with polyinosinic:polycytidylic acid (poly(I:C)), a well-known double-stranded RNA mimic that triggers a type-I interferon (IFN) response. Subsequently, a set of immune related genes, including mx, were analysed by real-time PCR on liver, spleen, head kidney and mid gut tissues. Results obtained confirmed that treatment with ß-glucan alone generally down-regulated the mRNA expression of selected cytokines when compared to untreated fish, while mx gene expression remained stable or was slightly up-regulated. Injection with poly(I:C) induced a similar down-regulated gene expression pattern for cytokines in samples from ß-glucan fed fish. In contrast, poly(I:C) injection markedly increased mx gene expression in samples from ß-glucan fed fish but hardly in samples from fish fed control feed. In an attempt to explain the high induction of mx, we studied Toll-like receptor 3 (TLR3) gene expression in these carp. TLR3 is a prototypical pattern recognition receptor considered important for the binding of viral double-stranded RNA and triggering of a type-I IFN response. Through genome data mining, two sequences for carp tlr3 were retrieved (tlr3.1 and tlr3.2) and characterized. Constitutive gene expression of both tlr3.1 and tlr3.2 was detected by real-time PCR in cDNA of all analysed carp organs. Strikingly, 25 days after ß-glucan feeding, very high levels of tlr3.1 gene expression were observed in all analysed organs, with the exception of the liver. Our data suggest that ß-glucan-mediated protection against viral diseases could be due to an increased Tlr3-mediated recognition of ligands, resulting in an increased antiviral activity of Mx.

Accessory molecules for Toll-like receptors in Teleost fish. Identification of TLR4 interactor with leucine-rich repeats (TRIL).

The biosynthesis and activation of Toll-like receptors (TLRs) requires accessory proteins. In mammals, a number of accessory proteins have been characterized, that can be classified based on their function as ligand-recognition and delivery cofactors, chaperones and trafficking proteins. We identified the homologs in teleost fish genomes of mammalian accessory molecules and show their expression in transcriptome data sets. Further, we annotate in detail TLR4 interactor with leucine-rich repeats (tril) in zebrafish (Danio rerio) and in common carp (Cyprinus carpio). In mammals, TRIL is a functional component of the TLR4 complex and is important for TLR3 signaling, and is mainly expressed in the brain. In fish, the Tril molecule has many conserved features of mouse and human TRIL, containing 13 leucine-rich repeat domains, a fibronectin and a transmembrane domain. Zebrafish tril could not be detected in the latest assembly of the zebrafish genome (Zv9) and required manual annotation based on genome and transcriptome shotgun sequencing data sets. Carp tril was found in two copies in the draft genome. Both copies of carp tril are constitutively expressed in several organs, with the highest gene expression in muscle, skin and brain. In carp, the tril gene is expressed at high levels in endothelial cells and thrombocytes. We discuss the implication of the presence of most, but not all, accessory molecules for the biosynthesis and activation of tlr molecules in fish.