Publications by authors named "Makedonka Mitreva"

192 Publications

Phylum-Spanning Neuropeptide GPCR Identification and Prioritization: Shaping Drug Target Discovery Pipelines for Nematode Parasite Control.

Front Endocrinol (Lausanne) 2021 30;12:718363. Epub 2021 Sep 30.

Microbes and Pathogen Biology, The Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Belfast, United Kingdom.

Nematode parasites undermine human health and global food security. The frontline anthelmintic portfolio used to treat parasitic nematodes is threatened by the escalation of anthelmintic resistance, resulting in a demand for new drug targets for parasite control. Nematode neuropeptide signalling pathways represent an attractive source of novel drug targets which currently remain unexploited. The complexity of the nematode neuropeptidergic system challenges the discovery of new targets for parasite control, however recent advances in parasite 'omics' offers an opportunity for the identification and prioritization of targets to seed anthelmintic discovery pipelines. In this study we employed Hidden Markov Model-based searches to identify ~1059 neuropeptide G-protein coupled receptor () encoding gene homologs in the predicted protein datasets of 10 key parasitic nematodes that span several phylogenetic clades and lifestyles. We show that, whilst parasitic nematodes possess a reduced complement of , several receptors are broadly conserved across nematode species. To prioritize the most appealing parasitic nematode NP-GPCR anthelmintic targets, we developed a novel nematode parasite drug target prioritization pipeline that incorporates pan-phylum conservation, derived reverse genetics phenotype, and parasite life-stage specific expression datasets. Several NP-GPCRs emerge as the most attractive anthelmintic targets for broad spectrum nematode parasite control. Our analyses have also identified the most appropriate targets for species- and life stage- directed chemotherapies; in this context we have identified several with macrofilaricidal potential. These data focus functional validation efforts towards the most appealing NP-GPCR targets and, in addition, the prioritization strategy employed here provides a blueprint for parasitic nematode target selection beyond NP-GPCRs.
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http://dx.doi.org/10.3389/fendo.2021.718363DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8515059PMC
September 2021

Informs Extrasynaptic Volume Transmission in Nematodes.

ACS Chem Neurosci 2021 09 4;12(17):3176-3188. Epub 2021 Aug 4.

Microbes and Pathogen Biology, The Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Belfast BT9 5DL, U.K.

Neural circuit synaptic connectivities (the connectome) provide the anatomical foundation for our understanding of nematode nervous system function. However, other nonsynaptic routes of communication are known in invertebrates including extrasynaptic volume transmission (EVT), which enables short- and/or long-range communication in the absence of synaptic connections. Although EVT has been highlighted as a facet of neurosignaling, no experimental evidence identifies body cavity fluid (pseudocoelomic fluid; PCF) as a vehicle for either neuropeptide or biogenic amine transmission. In the parasitic nematode , FMRFamide-like peptides encoded on potently stimulate female reproductive organs but are expressed in cells that are anatomically distant from the reproductive organ, with no known synaptic connections to this tissue. Here we investigate nonsynaptic neuropeptide signaling in nematodes mediated by the body cavity fluid. Our data show that (i) PCF (As-PCF) contains a catalog of neuropeptides including FMRFamide-like peptides and neuropeptide-like proteins, (ii) the FMRFamide-like peptide As-FLP-18A dominates the As-PCF peptidome, (iii) As-PCF potently modulates nematode reproductive muscle function , mirroring the effects of synthetic FLP-18 peptides, (iv) As-PCF activates the FLP-18 receptors NPR-4 and -5, (v) As-PCF alters behavior, and (vi) FLP-18 and FLP-18 receptors display pan-phylum distribution in nematodes. This study provides the first direct experimental evidence to support an extrasynaptic volume route for neuropeptide transmission in nematodes. These data indicate nonsynaptic signaling within the nematode functional connectome and are particularly pertinent to receptor deorphanization approaches underpinning drug discovery programs for nematode pathogens.
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http://dx.doi.org/10.1021/acschemneuro.1c00281DOI Listing
September 2021

Lung Epithelial Signaling Mediates Early Vaccine-Induced CD4 T Cell Activation and Control.

mBio 2021 08 13;12(4):e0146821. Epub 2021 Jul 13.

Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, USA.

Tuberculosis (TB) is one of the leading causes of death due to a single infectious agent. The development of a TB vaccine that induces durable and effective immunity to Mycobacterium tuberculosis () infection is urgently needed. Early and superior control can be induced in M. bovis Bacillus Calmette-Guérin (BCG)-vaccinated hosts when the innate immune response is targeted to generate effective vaccine-induced immunity. In the present study, we show that innate activation of DCs is critical for mucosal localization of clonally activated vaccine-induced CD4 T cells in the lung and superior early control. In addition, our study reveals that Th1/Th17 cytokine axis play an important role in superior vaccine-induced immunity. Our studies also show that activation of the nuclear factor kappa-light-chain enhancer of activated B cell (NF-κβ) pathway in lung epithelial cells is critical for the mucosal localization of activated vaccine-induced CD4 T cells for rapid control. Thus, our study provides novel insights into the immune mechanisms that can overcome TB vaccine bottlenecks and provide early rapid control. Tuberculosis is a leading cause of death due to single infectious agent accounting 1.4 million deaths each year. The only licensed vaccine, BCG, is not effective due to variable efficacy. In our study, we determined the early immune events necessary for achieving complete protection in a BCG-vaccinated host. Our study reveals that innate activation of DCs can mediate superior and early control in BCG-vaccinated mice through lung epithelial cell signaling and localization of clonal activated, antigen-specific, cytokine-producing CD4 T cells within the lung parenchyma and airways. Thus, our study provides novel insights into the immune mechanisms that can overcome TB vaccine bottlenecks and provide early rapid control.
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http://dx.doi.org/10.1128/mBio.01468-21DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8406195PMC
August 2021

Cell Death and Transcriptional Responses Induced in Larvae of the Nematode by Toxins/Toxicants with Broad Phylogenetic Efficacy.

Pharmaceuticals (Basel) 2021 Jun 22;14(7). Epub 2021 Jun 22.

Department of Medicine, Division of Infectious Diseases, Washington University School of Medicine, St. Louis, MO 63110, USA.

Establishing methods to investigate treatments that induce cell death in parasitic nematodes will promote experimental approaches to elucidate mechanisms and to identify prospective anthelmintics capable of inducing this outcome. Here, we extended recent progress on a method to monitor cell death and to identify small molecule inhibitors in to , a phylogenetically distant parasitic nematode of significance for both human and agricultural animal health. We utilized a diverse group of small molecule inhibitors referred to as nematode intestinal toxins/toxicants (NITs) coupled with motility, cytological and cell death assays to resolve gross effects on motility and individual cells and organ systems of two larval stages in culture. Early transcriptional response evaluation identified NIT-responsive genes and pathways. The scope of death among cells in larvae varied among NITs but shared patterns with , despite the approach having some limitations due to characteristics of larvae. Gene response patterns varied among NITs tested and provided information on the cell targets and pathways affected. Experimental NIT assays provide tools capable of inducing cell death in larval stages of parasitic nematodes, and can resolve many individual cells and organ systems in which cell death can be induced.
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http://dx.doi.org/10.3390/ph14070598DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8308827PMC
June 2021

Isolation and characterization of a novel bacteriophage WO from Allonemobius socius crickets in Missouri.

PLoS One 2021 1;16(7):e0250051. Epub 2021 Jul 1.

Infectious Disease Division, Washington University School of Medicine, St. Louis, Missouri, United States of America.

Wolbachia are endosymbionts of numerous arthropod and some nematode species, are important for their development and if present can cause distinct phenotypes of their hosts. Prophage DNA has been frequently detected in Wolbachia, but particles of Wolbachia bacteriophages (phage WO) have been only occasionally isolated. Here, we report the characterization and isolation of a phage WO of the southern ground cricket, Allonemobius socius, and provided the first whole-genome sequence of phage WO from this arthropod family outside of Asia. We screened A. socius abdomen DNA extracts from a cricket population in eastern Missouri by quantitative PCR for Wolbachia surface protein and phage WO capsid protein and found a prevalence of 55% and 50%, respectively, with many crickets positive for both. Immunohistochemistry using antibodies against Wolbachia surface protein showed many Wolbachia clusters in the reproductive system of female crickets. Whole-genome sequencing using Oxford Nanopore MinION and Illumina technology allowed for the assembly of a high-quality, 55 kb phage genome containing 63 open reading frames (ORF) encoding for phage WO structural proteins and host lysis and transcriptional manipulation. Taxonomically important regions of the assembled phage genome were validated by Sanger sequencing of PCR amplicons. Analysis of the nucleotides sequences of the ORFs encoding the large terminase subunit (ORF2) and minor capsid (ORF7) frequently used for phage WO phylogenetics showed highest homology to phage WOAu of Drosophila simulans (94.46% identity) and WOCin2USA1 of the cherry fruit fly, Rhagoletis cingulata (99.33% identity), respectively. Transmission electron microscopy examination of cricket ovaries showed a high density of phage particles within Wolbachia cells. Isolation of phage WO revealed particles characterized by 40-62 nm diameter heads and up to 190 nm long tails. This study provides the first detailed description and genomic characterization of phage WO from North America that is easily accessible in a widely distributed cricket species.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0250051PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8248633PMC
November 2021

Whipworm-Associated Intestinal Microbiome Members Consistent Across Both Human and Mouse Hosts.

Front Cell Infect Microbiol 2021 11;11:637570. Epub 2021 Mar 11.

Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, United States.

The human whipworm infects 289 million people worldwide, resulting in substantial morbidity. Whipworm infections are difficult to treat due to low cure rates and high reinfection rates. Interactions between whipworm and its host's intestinal microbiome present a potential novel target for infection control or prevention but are very complicated and are identified using inconsistent methodology and sample types across the literature, limiting their potential usefulness. Here, we used a combined 16S rRNA gene OTU analysis approach (QIIME2) for samples from humans and mice infected with whipworm ( and , respectively) to identify for the first time, bacterial taxa that were consistently associated with whipworm infection spanning host species and infection status using four independent comparisons (baseline infected vs uninfected and before vs after deworming for both humans and mice). Using these four comparisons, we identified significant positive associations for seven taxa including , which has been identified to induce whipworm egg hatching, and , which has previously been identified as a major component of the whipworm internal microbiome. We additionally identified significant negative associations for five taxa including four members of the order , two from the family , including which was previously identified as positively associated with whipworm in independent human and mouse studies. Using this approach, bacterial taxa of interest for future association and mechanistic studies were identified, and several were validated by RT-qPCR. We demonstrate the applicability of a mouse animal model for comparison to human whipworm infections with respect to whipworm-induced intestinal microbiome disruption and subsequent restoration following deworming. Overall, the novel cross-species analysis approach utilized here provides a valuable research tool for studies of the interaction between whipworm infection and the host intestinal microbiome.
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http://dx.doi.org/10.3389/fcimb.2021.637570DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7991909PMC
July 2021

IFN signaling and neutrophil degranulation transcriptional signatures are induced during SARS-CoV-2 infection.

Commun Biol 2021 03 5;4(1):290. Epub 2021 Mar 5.

Department of Molecular Microbiology, Washington University in St. Louis, St. Louis, MO, USA.

SARS-CoV-2 virus has infected more than 92 million people worldwide resulting in the Coronavirus disease 2019 (COVID-19). Using a rhesus macaque model of SARS-CoV-2 infection, we have characterized the transcriptional signatures induced in the lungs of juvenile and old macaques following infection. Genes associated with Interferon (IFN) signaling, neutrophil degranulation and innate immune pathways are significantly induced in macaque infected lungs, while pathways associated with collagen formation are downregulated, as also seen in lungs of macaques with tuberculosis. In COVID-19, increasing age is a significant risk factor for poor prognosis and increased mortality. Type I IFN and Notch signaling pathways are significantly upregulated in lungs of juvenile infected macaques when compared with old infected macaques. These results are corroborated with increased peripheral neutrophil counts and neutrophil lymphocyte ratio in older individuals with COVID-19 disease. Together, our transcriptomic studies have delineated disease pathways that improve our understanding of the immunopathogenesis of COVID-19.
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http://dx.doi.org/10.1038/s42003-021-01829-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7935909PMC
March 2021

Areas of Metabolomic Exploration for Helminth Infections.

ACS Infect Dis 2021 02 25;7(2):206-214. Epub 2021 Jan 25.

Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63130, United States.

Helminths represent a diverse category of parasitic organisms that can thrive within a host for years, if not decades, in the absence of treatment. As such, they must establish mechanisms to subsist off their hosts, evade the immune system, and develop a niche among the other cohabiting microbial communities. The complex interplay of biologically small molecules (collectively known as the metabolome) derived from, utilized by, or in response to the presence of helminths within a host is an emerging field of study. In this Perspective, we briefly summarize the current existing literature, categorize key host-pathogen-microbiome interfaces that could be studied in the context of the metabolome, and provide background on mass spectrometry-based metabolomic methodology. Overall, we hope to provide a comprehensive guide for utilizing metabolomics in the context of helminthic disease.
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http://dx.doi.org/10.1021/acsinfecdis.0c00658DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7887738PMC
February 2021

An Integrated Approach to Identify New Anti-Filarial Leads to Treat River Blindness, a Neglected Tropical Disease.

Pathogens 2021 Jan 14;10(1). Epub 2021 Jan 14.

Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, 4523 Clayton Ave., St. Louis, MO 63110, USA.

Filarial worms cause multiple debilitating diseases in millions of people worldwide, including river blindness. Currently available drugs reduce transmission by killing larvae (microfilariae), but there are no effective cures targeting the adult parasites (macrofilaricides) which survive and reproduce in the host for very long periods. To identify effective macrofilaricides, we carried out phenotypic screening of a library of 2121 approved drugs for clinical use against adult and prioritized the hits for further studies by integrating those results with a computational prioritization of drugs and associated targets. This resulted in the identification of 18 hits with anti-macrofilaricidal activity, of which two classes, azoles and aspartic protease inhibitors, were further expanded upon. Follow up screening against spp. (adult and pre-adult ) confirmed activity for 13 drugs (the majority having IC < 10 μM), and a counter screen of a subset against microfilariae showed the potential to identify selective drugs that prevent adverse events when co-infected individuals are treated. Stage specific activity was also observed. Many of these drugs are amenable to structural optimization, and also have known canonical targets, making them promising candidates for further optimization that can lead to identifying and characterizing novel anti-macrofilarial drugs.
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http://dx.doi.org/10.3390/pathogens10010071DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7830784PMC
January 2021

Altered ratio of dendritic cell subsets in skin-draining lymph nodes promotes Th2-driven contact hypersensitivity.

Proc Natl Acad Sci U S A 2021 01;118(3)

Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110;

Plasmacytoid dendritic cells (pDCs) specialize in the production of type I IFN (IFN-I). pDCs can be depleted in vivo by injecting diphtheria toxin (DT) in a mouse in which pDCs express a diphtheria toxin receptor (DTR) transgene driven by the human CLEC4C promoter. This promoter is enriched for binding sites for TCF4, a transcription factor that promotes pDC differentiation and expression of pDC markers, including CLEC4C. Here, we found that injection of DT in CLEC4C-DTR mice markedly augmented Th2-dependent skin inflammation in a model of contact hypersensitivity (CHS) induced by the hapten fluorescein isothiocyanate. Unexpectedly, this biased Th2 response was independent of reduced IFN-I accompanying pDC depletion. In fact, DT treatment altered the representation of conventional dendritic cells (cDCs) in the skin-draining lymph nodes during the sensitization phase of CHS; there were fewer Th1-priming CD326 CD103 cDC1 and more Th2-priming CD11b cDC2. Single-cell RNA-sequencing of CLEC4C-DTR cDCs revealed that CD326 DCs, like pDCs, expressed DTR and were depleted together with pDCs by DT treatment. Since CD326 DCs did not express , DTR expression might be driven by yet-undefined transcription factors activating the CLEC4C promoter. These results demonstrate that altered DC representation in the skin-draining lymph nodes during sensitization to allergens can cause Th2-driven CHS.
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http://dx.doi.org/10.1073/pnas.2021364118DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7826349PMC
January 2021

Alteration of the fecal microbiota in Chinese patients with Schistosoma japonicum infection.

Parasite 2021 8;28. Epub 2021 Jan 8.

National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, 200025 Shanghai, PR China - Chinese Center for Tropical Diseases Research, 200025 Shanghai, PR China - World Health Organization Collaborating Centre for Tropical Diseases, 200025 Shanghai, PR China - Key Laboratory of Parasite and Vector Biology, National Health Commission of the People's Republic of China, 200025 Shanghai, PR China.

Schistosoma japonicum infection causes pathological injury to the host. Multiple studies have shown that intestinal helminth infection causes dysbiosis for the gut microbial community and impacts host immunology. However, the effect of acute S. japonicum infection on the gut microbiome structure (abundance and diversity) is still unclear. We collected fecal samples from healthy and infected patients from a single hospital in Hunan Province, China. The bacterial community was analyzed using 16S ribosomal RNA gene sequencing of the V4 hypervariable region using the HiSeq platform. Compared with healthy subjects, infected patients exhibited an increase in relative abundance of the TM7 phylum. At the genus level, there were seven differentially abundant genera between groups. The most significant finding was a Bacteroides enterotype in patients with acute schistosomiasis. These results suggest that S. japonicum infection has a significant effect on microbiome composition characterized by a higher abundance of the TM7 phylum and development of a Bacteroides enterotype.
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http://dx.doi.org/10.1051/parasite/2020074DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7792497PMC
February 2021

Characterization and localization of antigens for serodiagnosis of human paragonimiasis.

Parasitol Res 2021 Feb 8;120(2):535-545. Epub 2021 Jan 8.

Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, 4444 Forest Park Blvd, St. Louis, MO, 63110, USA.

Paragonimiasis is a foodborne trematode infection that affects 23 million people, mainly in Asia. Lung fluke infections lead frequently to chronic cough with fever and hemoptysis, and are often confused with lung cancer or tuberculosis. Paragonimiasis can be efficiently treated with praziquantel, but diagnosis is often delayed, and patients are frequently treated for other conditions. To improve diagnosis, we selected five Paragonimus kellicotti proteins based on transcriptional abundance, recognition by patient sera, and conservation among trematodes and expressed them as His-fusion proteins in Escherichia coli. Sequences for these proteins have 76-99% identity with amino acid sequences for orthologs in the genomes of Paragonimus westermani, Paragonimus heterotremus, and Paragonimus miyazakii. Immunohistology studies showed that antibodies raised to four recombinant proteins bound to the tegument of adult P. kellicotti worms, at the parasite host interface. Only a known egg antigen was absent from the tegument but present in developing and mature eggs. We evaluated the diagnostic potential of these antigens by Western blot with sera from patients with paragonimiasis (from MO and the Philippines), fascioliasis, and schistosomiasis, and with sera from healthy North American controls. Two recombinant proteins (a cysteine protease and a myoglobin) showed the highest sensitivity and specificity as diagnostic antigens, and they detected antibodies in sera from paragonimiasis patients with early or mature infections. In contrast, antibodies to egg yolk ferritin appeared to be specific marker for patients with adult fluke infections that produce eggs. Our study has identified and localized antigens that are promising for serodiagnosis of human paragonimiasis.
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http://dx.doi.org/10.1007/s00436-020-06990-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7854406PMC
February 2021

Responses to acute infection with SARS-CoV-2 in the lungs of rhesus macaques, baboons and marmosets.

Nat Microbiol 2021 01 18;6(1):73-86. Epub 2020 Dec 18.

Texas Biomedical Research Institute, San Antonio, TX, USA.

Non-human primate models will expedite therapeutics and vaccines for coronavirus disease 2019 (COVID-19) to clinical trials. Here, we compare acute severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in young and old rhesus macaques, baboons and old marmosets. Macaques had clinical signs of viral infection, mild to moderate pneumonitis and extra-pulmonary pathologies, and both age groups recovered in two weeks. Baboons had prolonged viral RNA shedding and substantially more lung inflammation compared with macaques. Inflammation in bronchoalveolar lavage was increased in old versus young baboons. Using techniques including computed tomography imaging, immunophenotyping, and alveolar/peripheral cytokine response and immunohistochemical analyses, we delineated cellular immune responses to SARS-CoV-2 infection in macaque and baboon lungs, including innate and adaptive immune cells and a prominent type-I interferon response. Macaques developed T-cell memory phenotypes/responses and bystander cytokine production. Old macaques had lower titres of SARS-CoV-2-specific IgG antibody levels compared with young macaques. Acute respiratory distress in macaques and baboons recapitulates the progression of COVID-19 in humans, making them suitable as models to test vaccines and therapies.
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http://dx.doi.org/10.1038/s41564-020-00841-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7890948PMC
January 2021

Characterization of the Complete Mitochondrial Genomes of Two Sibling Species of Parasitic Roundworms, and .

Front Genet 2020 8;11:573395. Epub 2020 Oct 8.

McDonnell Genome Institute and Department of Medicine, Washington University School of Medicine, Saint Louis, MO, United States.

and are among the two most pathogenic internal parasitic nematodes infecting small ruminants, such as sheep and goats, and are a global animal health issue. Accurate identification and delineation of Haemonchidae species is essential for development of diagnostic and control strategies with high resolution for Trichostrongyloidea infection in ruminants. Here, we describe in detail and compare the complete mitochondrial (mt) genomes of the New Zealand and field strains to improve our understanding of species- and strain-level evolution in these closely related roundworms. In the present study, we performed extensive comparative bioinformatics analyses on the recently sequenced complete mt genomes of the New Zealand NZ_Hco_NP and NZ_Teci_NP field strains. Amino acid sequences inferred from individual genes of each of the two mt genomes were compared, concatenated and subjected to phylogenetic analysis using Bayesian inference (BI), Maximum Likelihood (ML), and Maximum Parsimony (MP). The AT-rich mt genomes of NZ_Hco_NP and NZ_Teci_NP are 14,001 bp (A+T content of 77.4%) and 14,081 bp (A+T content of 77.3%) in size, respectively. All 36 of the typical nematode mt genes are transcribed in the forward direction in both species and comprise of 12 protein-encoding genes (PCGs), 2 ribosomal RNA () genes, and 22 transfer RNA () genes. The secondary structures for the 22 genes and two genes differ between NZ_Hco_NP and NZ_Teci_NP, however the gene arrangements of both are consistent with other Trichostrongylidea sequenced to date. Comparative analyses of the complete mitochondrial nucleotide sequences, PCGs, A+T rich and non-coding repeat regions of NZ_Hco_NP and NZ_Teci_NP further reinforces the high levels of diversity and gene flow observed among Trichostrongylidea, and supports their potential as ideal markers for strain-level identification from different hosts and geographical regions with high resolution for future studies. The complete mt genomes of NZ_Hco_NP and NZ_Teci_NP presented here provide useful novel markers for further studies of the meta-population connectivity and the genetic mechanisms driving evolution in nematode species.
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http://dx.doi.org/10.3389/fgene.2020.573395DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7578395PMC
October 2020

Rapid determination of nematode cell and organ susceptibility to toxic treatments.

Int J Parasitol Drugs Drug Resist 2020 12 20;14:167-182. Epub 2020 Oct 20.

Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA; Department of Genetics, Washington University School of Medicine, St. Louis, MO 63110, St. Louis, MO, 63110, USA; McDonnell Genome Institute, Washington University School of Medicine, St. Louis, Missouri, 63108, USA. Electronic address:

In research focused on the intestine of parasitic nematodes, we recently identified small molecule inhibitors toxic to intestinal cells of larval Ascaris suum (nematode intestinal toxins/toxicants; "NITs"). Some NITs had anthelmintic activity across the phylogenetic diversity of the Nematoda. The whole-worm motility inhibition assay quantified anthelmintic activity, but worm responses to NITs in relation to pathology or affected molecular pathways was not acquired. In this study we extended this research to more comprehensively determine in whole larval A. suum the cells, organ systems, molecular targets, and potential cellular pathways involved in mechanisms of toxicity leading to cell death. The experimental system utilized fluorescent nuclear probes (bisbenzimide, propidium iodide), NITs, an A. suum larval parasite culture system and transcriptional responses (RNA-seq) to NITs. The approach provides for rapid resolution of NIT-induced cell death among organ systems (e.g. intestine, excretory, esophagus, hypodermis and seam cells, and nervous), discriminates among NITs based on cell death profiles, and identifies cells and organ systems with the greatest NIT sensitivity (e.g. intestine and apparent neuronal cells adjacent to the nerve ring). Application was extended to identify cells and organs sensitive to several existing anthelmintics. This approach also resolved intestinal cell death and irreparable damage induced in adult A. suum by two NITs, establishing a new model to elucidate relevant pathologic mechanisms in adult worms. RNA-seq analysis resolved A. suum genes responsive to treatments with three NITs, identifying dihydroorotate dehydrogenase (uridine synthesis) and RAB GTPase(s) (vesicle transport) as potential targets/pathways leading to cell death. A set of genes induced by all three NITs tested suggest common stress or survival responses activated by NITs. Beyond the presented specific lines of research, elements of the overall experimental system presented in this study have broad application toward systematic development of new anthelmintics.
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http://dx.doi.org/10.1016/j.ijpddr.2020.10.007DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7593349PMC
December 2020

Editorial: Novel Frontiers in Helminth Genomics.

Front Genet 2020 14;11:791. Epub 2020 Aug 14.

Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, United Kingdom.

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http://dx.doi.org/10.3389/fgene.2020.00791DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7456986PMC
August 2020

IFN signaling and neutrophil degranulation transcriptional signatures are induced during SARS-CoV-2 infection.

bioRxiv 2020 Aug 6. Epub 2020 Aug 6.

Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, TX 78245.

The novel virus SARS-CoV-2 has infected more than 14 million people worldwide resulting in the Coronavirus disease 2019 (COVID-19). Limited information on the underlying immune mechanisms that drive disease or protection during COVID-19 severely hamper development of therapeutics and vaccines. Thus, the establishment of relevant animal models that mimic the pathobiology of the disease is urgent. Rhesus macaques infected with SARS-CoV-2 exhibit disease pathobiology similar to human COVID-19, thus serving as a relevant animal model. In the current study, we have characterized the transcriptional signatures induced in the lungs of juvenile and old rhesus macaques following SARS-CoV-2 infection. We show that genes associated with Interferon (IFN) signaling, neutrophil degranulation and innate immune pathways are significantly induced in macaque infected lungs, while pathways associated with collagen formation are downregulated. In COVID-19, increasing age is a significant risk factor for poor prognosis and increased mortality. We demonstrate that Type I IFN and Notch signaling pathways are significantly upregulated in lungs of juvenile infected macaques when compared with old infected macaques. These results are corroborated with increased peripheral neutrophil counts and neutrophil lymphocyte ratio in older individuals with COVID-19 disease. In contrast, pathways involving VEGF are downregulated in lungs of old infected macaques. Using samples from humans with SARS-CoV-2 infection and COVID-19, we validate a subset of our findings. Finally, neutrophil degranulation, innate immune system and IFN gamma signaling pathways are upregulated in both tuberculosis and COVID-19, two pulmonary diseases where neutrophils are associated with increased severity. Together, our transcriptomic studies have delineated disease pathways to improve our understanding of the immunopathogenesis of COVID-19 to facilitate the design of new therapeutics for COVID-19.
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http://dx.doi.org/10.1101/2020.08.06.239798DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7418717PMC
August 2020

Comparative genomics and transcriptomics of 4 Paragonimus species provide insights into lung fluke parasitism and pathogenesis.

Gigascience 2020 07;9(7)

Department of Internal Medicine, Washington University School of Medicine, 660 S Euclid Ave, St. Louis, MO 63110, USA.

Background: Paragonimus spp. (lung flukes) are among the most injurious foodborne helminths, infecting ∼23 million people and subjecting ∼292 million to infection risk. Paragonimiasis is acquired from infected undercooked crustaceans and primarily affects the lungs but often causes lesions elsewhere including the brain. The disease is easily mistaken for tuberculosis owing to similar pulmonary symptoms, and accordingly, diagnostics are in demand.

Results: We assembled, annotated, and compared draft genomes of 4 prevalent and distinct Paragonimus species: Paragonimus miyazakii, Paragonimus westermani, Paragonimus kellicotti, and Paragonimus heterotremus. Genomes ranged from 697 to 923 Mb, included 12,072-12,853 genes, and were 71.6-90.1% complete according to BUSCO. Orthologous group analysis spanning 21 species (lung, liver, and blood flukes, additional platyhelminths, and hosts) provided insights into lung fluke biology. We identified 256 lung fluke-specific and conserved orthologous groups with consistent transcriptional adult-stage Paragonimus expression profiles and enriched for iron acquisition, immune modulation, and other parasite functions. Previously identified Paragonimus diagnostic antigens were matched to genes, providing an opportunity to optimize and ensure pan-Paragonimus reactivity for diagnostic assays.

Conclusions: This report provides advances in molecular understanding of Paragonimus and underpins future studies into the biology, evolution, and pathogenesis of Paragonimus and related foodborne flukes. We anticipate that these novel genomic and transcriptomic resources will be invaluable for future lung fluke research.
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http://dx.doi.org/10.1093/gigascience/giaa073DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7370270PMC
July 2020

The endosymbiont Wolbachia rebounds following antibiotic treatment.

PLoS Pathog 2020 07 8;16(7):e1008623. Epub 2020 Jul 8.

Dept. of Pharmaceutical Chemistry; University of California, San Francisco; San Francisco, California, United States of America.

Antibiotic treatment has emerged as a promising strategy to sterilize and kill filarial nematodes due to their dependence on their endosymbiotic bacteria, Wolbachia. Several studies have shown that novel and FDA-approved antibiotics are efficacious at depleting the filarial nematodes of their endosymbiont, thus reducing female fecundity. However, it remains unclear if antibiotics can permanently deplete Wolbachia and cause sterility for the lifespan of the adult worms. Concerns about resistance arising from mass drug administration necessitate a careful exploration of potential Wolbachia recrudescence. In the present study, we investigated the long-term effects of the FDA-approved antibiotic, rifampicin, in the Brugia pahangi jird model of infection. Initially, rifampicin treatment depleted Wolbachia in adult worms and simultaneously impaired female worm fecundity. However, during an 8-month washout period, Wolbachia titers rebounded and embryogenesis returned to normal. Genome sequence analyses of Wolbachia revealed that despite the population bottleneck and recovery, no genetic changes occurred that could account for the rebound. Clusters of densely packed Wolbachia within the worm's ovarian tissues were observed by confocal microscopy and remained in worms treated with rifampicin, suggesting that they may serve as privileged sites that allow Wolbachia to persist in worms while treated with antibiotic. To our knowledge, these clusters have not been previously described and may be the source of the Wolbachia rebound.
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http://dx.doi.org/10.1371/journal.ppat.1008623DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7371230PMC
July 2020

Transcriptomic analysis of hookworm Ancylostoma ceylanicum life cycle stages reveals changes in G-protein coupled receptor diversity associated with the onset of parasitism.

Int J Parasitol 2020 07 25;50(8):603-610. Epub 2020 Jun 25.

Department of Microbiology, Immunology and Tropical Medicine, The George Washington University, Washington DC, USA. Electronic address:

Free-living nematodes respond to variable and unpredictable environmental stimuli whereas parasitic nematodes exist in a more stable host environment. A positive correlation between the presence of environmental stages in the nematode life cycle and an increasing number of G-protein coupled receptors (GPCRs) reflects this difference in free-living and parasitic lifestyles. As hookworm larvae move from the external environment into a host, they detect uncharacterized host components, initiating a signalling cascade that results in the resumption of development and eventual maturation. Previous studies suggest this process is mediated by GPCRs in amphidial neurons. Here we set out to uncover candidate GPCRs required by a hookworm to recognise its host. First, we identified all potential Ancylostoma ceylanicum GPCRs encoded in the genome. We then used life cycle stage-specific RNA-seq data to identify differentially expressed GPCRs between the free-living infective L3 (iL3) and subsequent parasitic stages to identify receptors involved in the transition to parasitism. We reasoned that GPCRs involved in host recognition and developmental activation would be expressed at higher levels in the environmental iL3 stage than in subsequent stages. Our results support the model that a decrease in GPCR diversity occurs as the larvae develop from the free-living iL3 stage to the parasitic L3 (pL3) in the host over 24-72 h. We find that overall GPCR expression and diversity is highest in the iL3 compared with subsequent parasitic stages. By 72 h, there was an approximately 50% decrease in GPCR richness associated with the moult from the pL3 to the L4. Taken together, our data uncover a negative correlation between GPCR diversity and parasitic development in hookworm. Finally, we demonstrate proof of principal that Caenorhabditis elegans can be used as a heterologous system to examine the expression pattern of candidate host signal chemoreceptors (CRs) from hookworm. We observe expression of candidate host signal CRs in C. elegans, demonstrating that C. elegans can be effectively used as a surrogate to identify expressed hookworm genes. We present several preliminary examples of this strategy and confirm a candidate CR as neuronally expressed.
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http://dx.doi.org/10.1016/j.ijpara.2020.05.003DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7454011PMC
July 2020

Author Correction: A transcriptomic analysis of the phylum Nematoda.

Nat Genet 2020 Jul;52(7):750

School of Biological Sciences, University of Edinburgh, Edinburgh, UK.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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http://dx.doi.org/10.1038/s41588-020-0658-6DOI Listing
July 2020

Comprehensive analysis of the secreted proteome of adult Necator americanus hookworms.

PLoS Negl Trop Dis 2020 05 26;14(5):e0008237. Epub 2020 May 26.

Centre for Molecular Therapeutics, Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, QLD, Australia.

The human hookworm Necator americanus infects more than 400 million people worldwide, contributing substantially to the poverty in these regions. Adult stage N. americanus live in the small intestine of the human host where they inject excretory/secretory (ES) products into the mucosa. ES products have been characterized at the proteome level for a number of animal hookworm species, but until now, the difficulty in obtaining sufficient live N. americanus has been an obstacle in characterizing the secretome of this important human pathogen. Herein we describe the ES proteome of N. americanus and utilize this information along with RNA Seq data to conduct the first proteogenomic analysis of a parasitic helminth, significantly improving the available genome and thereby generating a robust description of the parasite secretome. The genome annotation resulted in a revised prediction of 3,425 fewer genes than initially reported, accompanied by a significant increase in the number of exons and introns, total gene length and the percentage of the genome covered by genes. Almost 200 ES proteins were identified by LC-MS/MS with SCP/TAPS proteins, 'hypothetical' proteins and proteases among the most abundant families. These proteins were compared to commonly used model species of human parasitic infections, including Ancylostoma caninum, Nippostrongylus brasiliensis and Heligmosomoides polygyrus. SCP/TAPS proteins are immunogenic in nematode infections, so we expressed four of those identified in this study in recombinant form and showed that they are all recognized to varying degrees by serum antibodies from hookworm-infected subjects from a disease-endemic area of Brazil. Our findings provide valuable information on important families of proteins with both known and unknown functions that could be instrumental in host-parasite interactions, including protein families that might be key for parasite survival in the onslaught of robust immune responses, as well as vaccine and diagnostic targets.
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http://dx.doi.org/10.1371/journal.pntd.0008237DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7274458PMC
May 2020

De novo identification of toxicants that cause irreparable damage to parasitic nematode intestinal cells.

PLoS Negl Trop Dis 2020 05 26;14(5):e0007942. Epub 2020 May 26.

Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, United States of America.

Efforts to identify new drugs for therapeutic and preventive treatments against parasitic nematodes have gained increasing interest with expanding pathogen omics databases and drug databases from which new anthelmintic compounds might be identified. Here, a novel approach focused on integrating a pan-Nematoda multi-omics data targeted to a specific nematode organ system (the intestinal tract) with evidence-based filtering and chemogenomic screening was undertaken. Based on de novo computational target prioritization of the 3,564 conserved intestine genes in A. suum, exocytosis was identified as a high priority pathway, and predicted inhibitors of exocytosis were tested using the large roundworm (Ascaris suum larval stages), a filarial worm (Brugia pahangi adult and L3), a whipworm (Trichuris muris adult), and the non-parasitic nematode Caenorhabditis elegans. 10 of 13 inhibitors were found to cause rapid immotility in A. suum L3 larvae, and five inhibitors were effective against the three phylogenetically diverse parasitic nematode species, indicating potential for a broad spectrum anthelmintics. Several distinct pathologic phenotypes were resolved related to molting, motility, or intestinal cell and tissue damage using conventional and novel histologic methods. Pathologic profiles characteristic for each inhibitor will guide future research to uncover mechanisms of the anthelmintic effects and improve on drug designs. This progress firmly validates the focus on intestinal cell biology as a useful resource to develop novel anthelmintic strategies.
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http://dx.doi.org/10.1371/journal.pntd.0007942DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7274465PMC
May 2020

Improving Characterization of Understudied Human Microbiomes Using Targeted Phylogenetics.

mSystems 2020 Feb 25;5(1). Epub 2020 Feb 25.

McDonnell Genome Institute at Washington University, St. Louis, Missouri, USA

Whole-genome bacterial sequences are required to better understand microbial functions, niche-specific bacterial metabolism, and disease states. Although genomic sequences are available for many of the human-associated bacteria from commonly tested body habitats (e.g., feces), as few as 13% of bacterium-derived reads from other sites such as the skin map to known bacterial genomes. To facilitate a better characterization of metagenomic shotgun reads from underrepresented body sites, we collected over 10,000 bacterial isolates originating from 14 human body habitats, identified novel taxonomic groups based on full-length 16S rRNA gene sequences, clustered the sequences to ensure that no individual taxonomic group was overselected for sequencing, prioritized bacteria from underrepresented body sites (such as skin and respiratory and urinary tracts), and sequenced and assembled genomes for 665 new bacterial strains. Here, we show that addition of these genomes improved read mapping rates of Human Microbiome Project (HMP) metagenomic samples by nearly 30% for the previously underrepresented phylum , and 27.5% of the novel genomes generated here had high representation in at least one of the tested HMP samples, compared to 12.5% of the sequences in the public databases, indicating an enrichment of useful novel genomic sequences resulting from the prioritization procedure. As our understanding of the human microbiome continues to improve and to enter the realm of therapy developments, targeted approaches such as this to improve genomic databases will increase in importance from both an academic and a clinical perspective. The human microbiome plays a critically important role in health and disease, but current understanding of the mechanisms underlying the interactions between the varying microbiome and the different host environments is lacking. Having access to a database of fully sequenced bacterial genomes provides invaluable insights into microbial functions, but currently sequenced genomes for the human microbiome have largely come from a limited number of body sites (primarily feces), while other sites such as the skin, respiratory tract, and urinary tract are underrepresented, resulting in as little as 13% of bacterium-derived reads mapping to known bacterial genomes. Here, we sequenced and assembled 665 new bacterial genomes, prioritized from a larger database to select underrepresented body sites and bacterial taxa in the existing databases. As a result, we substantially improve mapping rates for samples from the Human Microbiome Project and provide an important contribution to human bacterial genomic databases for future studies.
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http://dx.doi.org/10.1128/mSystems.00096-20DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7043343PMC
February 2020

Immune correlates of tuberculosis disease and risk translate across species.

Sci Transl Med 2020 01;12(528)

Department of Molecular Microbiology, Washington University in St. Louis, St. Louis, MO 63110, USA.

One quarter of the world's population is infected with (), the causative agent of tuberculosis (TB). Although most infected individuals successfully control or clear the infection, some individuals will progress to TB disease. Immune correlates identified using animal models are not always effectively translated to human TB, thus resulting in a slow pace of translational discoveries from animal models to human TB for many platforms including vaccines, therapeutics, biomarkers, and diagnostic discovery. Therefore, it is critical to improve our poor understanding of immune correlates of disease and protection that are shared across animal TB models and human TB. In this study, we have provided an in-depth identification of the conserved and diversified gene/immune pathways in TB models of nonhuman primate and diversity outbred mouse and human TB. Our results show that prominent differentially expressed genes/pathways induced during TB disease progression are conserved in genetically diverse mice, macaques, and humans. In addition, using gene-deficient inbred mouse models, we have addressed the functional role of individual genes comprising the gene signature of disease progression seen in humans with infection. We show that genes representing specific immune pathways can be protective, detrimental, or redundant in controlling infection and translate into identifying immune pathways that mediate TB immunopathology in humans. Together, our cross-species findings provide insights into modeling TB disease and the immunological basis of TB disease progression.
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http://dx.doi.org/10.1126/scitranslmed.aay0233DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7354419PMC
January 2020

De novo Assembly of the Brugia malayi Genome Using Long Reads from a Single MinION Flowcell.

Sci Rep 2019 12 20;9(1):19521. Epub 2019 Dec 20.

Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, United States.

Filarial nematode infections cause a substantial global disease burden. Genomic studies of filarial worms can improve our understanding of their biology and epidemiology. However, genomic information from field isolates is limited and available reference genomes are often discontinuous. Single molecule sequencing technologies can reduce the cost of genome sequencing and long reads produced from these devices can improve the contiguity and completeness of genome assemblies. In addition, these new technologies can make generation and analysis of large numbers of field isolates feasible. In this study, we assessed the performance of the Oxford Nanopore Technologies MinION for sequencing and assembling the genome of Brugia malayi, a human parasite widely used in filariasis research. Using data from a single MinION flowcell, a 90.3 Mb nuclear genome was assembled into 202 contigs with an N50 of 2.4 Mb. This assembly covered 96.9% of the well-defined B. malayi reference genome with 99.2% identity. The complete mitochondrial genome was obtained with individual reads and the nearly complete genome of the endosymbiotic bacteria Wolbachia was assembled alongside the nuclear genome. Long-read data from the MinION produced an assembly that approached the quality of a well-established reference genome using comparably fewer resources.
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http://dx.doi.org/10.1038/s41598-019-55908-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6925183PMC
December 2019

A Praziquantel Treatment Study of Immune and Transcriptome Profiles in Schistosoma haematobium-Infected Gabonese Schoolchildren.

J Infect Dis 2020 11;222(12):2103-2113

Department of Parasitology, Leiden University Medical Center, Leiden, The Netherlands.

Background: Although Schistosoma haematobium infection has been reported to be associated with alterations in immune function, in particular immune hyporesponsiveness, there have been only few studies that have used the approach of removing infection by drug treatment to establish this and to understand the underlying molecular mechanisms.

Methods: Schistosoma haematobium-infected schoolchildren were studied before and after praziquantel treatment and compared with uninfected controls. Cellular responses were characterized by cytokine production and flow cytometry, and in a subset of children RNA sequencing (RNA-Seq) transcriptome profiling was performed.

Results: Removal of S haematobium infection resulted in increased schistosome-specific cytokine responses that were negatively associated with CD4+CD25+FOXP3+ T-cells and accompanied by increased frequency of effector memory T-cells. Innate responses to Toll like receptor (TLR) ligation decreased with treatment and showed positive association with CD4+CD25+FOXP3+ T-cells. At the transcriptome level, schistosome infection was associated with enrichment in cell adhesion, whereas parasite removal was associated with a more quiescent profile. Further analysis indicated that alteration in cellular energy metabolism was associated with S haematobium infection and that the early growth response genes 2 and 3 (EGR 2 and EGR3), transcription factors that negatively regulate T-cell activation, may play a role in adaptive immune hyporesponsiveness.

Conclusions: Using a longitudinal study design, we found contrasting effects of schistosome infection on innate and adaptive immune responses. Whereas the innate immune system appears more activated, the adaptive immunity is in a hyporesponsive state reflected in alterations in CD4+CD25+FOXP3+ T-cells, cellular metabolism, and transcription factors involved in anergy.
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http://dx.doi.org/10.1093/infdis/jiz641DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7661769PMC
November 2020

Mycobacterium tuberculosis HN878 Infection Induces Human-Like B-Cell Follicles in Mice.

J Infect Dis 2020 04;221(10):1636-1646

Department of Molecular Microbiology, Washington University School of Medicine in St. Louis, St. Louis, Missouri, USA.

Specific spatial organization of granulomas within the lungs is crucial for protective anti-tuberculosis (TB) immune responses. However, only large animal models such as macaques are thought to reproduce the morphological hallmarks of human TB granulomas. In this study, we show that infection of mice with clinical "hypervirulent" Mycobacterium tuberculosis (Mtb) HN878 induces human-like granulomas composed of bacilli-loaded macrophages surrounded by lymphocytes and organized localization of germinal centers and B-cell follicles. Infection with laboratory-adapted Mtb H37Rv resulted in granulomas that are characterized by unorganized clusters of macrophages scattered between lymphocytes. An in-depth exploration of the functions of B cells within these follicles suggested diverse roles and the activation of signaling pathways associated with antigen presentation and immune cell recruitment. These findings support the use of clinical Mtb HN878 strain for infection in mice as an appropriate model to study immune parameters associated with human TB granulomas.
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http://dx.doi.org/10.1093/infdis/jiz663DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7184917PMC
April 2020

The Effect of Gut Microbiome Composition on Human Immune Responses: An Exploration of Interference by Helminth Infections.

Front Genet 2019 6;10:1028. Epub 2019 Nov 6.

Department of Parasitology, Leiden University Medical Center, Leiden, Netherlands.

Soil-transmitted helminths have been shown to have the immune regulatory capacity, which they use to enhance their long term survival within their host. As these parasites reside in the gastrointestinal tract, they might modulate the immune system through altering the gut bacterial composition. Although the relationships between helminth infections or the microbiome with the immune system have been studied separately, their combined interactions are largely unknown. In this study we aim to analyze the relationship between bacterial communities with cytokine response in the presence or absence of helminth infections. For 66 subjects from a randomized placebo-controlled trial, stool and blood samples were available at both baseline and 21 months after starting three-monthly albendazole treatment. The stool samples were used to identify the helminth infection status and fecal microbiota composition, while whole blood samples were cultured to obtain cytokine responses to innate and adaptive stimuli. When subjects were free of helminth infection (helminth-negative), increasing proportions of was associated with lower levels of IL-10 response to LPS {estimate [95% confidence interval (CI)] -1.96 (-3.05, -0.87)}. This association was significantly diminished when subjects were helminth-infected (helminth positive) (-value for the difference between helminth-negative versus helminth-positive was 0.002). Higher diversity was associated with greater IFN-γ responses to PHA in helminth-negative (0.95 (0.15, 1.75); versus helminth-positive [-0.07 (-0.88, 0.73), -value = 0.056] subjects. Albendazole treatment showed no direct effect in the association between bacterial proportion and cytokine responses, although the ' effect on IL-10 responses to LPS tended downward in the albendazole-treated group [-1.74 (-4.08, 0.59)] versus placebo [-0.11 (-0.84, 0.62); -value = 0.193]. We observed differences in the relationship between gut microbiome composition and immune responses, when comparing individuals infected or uninfected with geohelminths. Although these findings are part of a preliminary exploration, the data support the hypothesis that intestinal helminths may modulate immune responses, in unison with the gut microbiota. ISRCTN, ISRCTN83830814. Registered 27 February 2008 - Retrospectively registered, http://www.isrctn.com/ISRCTN83830814.
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http://dx.doi.org/10.3389/fgene.2019.01028DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6856646PMC
November 2019
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