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  1. Article ; Online: Anomalous diffusion and asymmetric tempering memory in neutrophil chemotaxis.

    Peter Dieterich / Otto Lindemann / Mats Leif Moskopp / Sebastien Tauzin / Anna Huttenlocher / Rainer Klages / Aleksei Chechkin / Albrecht Schwab

    PLoS Computational Biology, Vol 18, Iss 5, p e

    2022  Volume 1010089

    Abstract: The motility of neutrophils and their ability to sense and to react to chemoattractants in their environment are of central importance for the innate immunity. Neutrophils are guided towards sites of inflammation following the activation of G-protein ... ...

    Abstract The motility of neutrophils and their ability to sense and to react to chemoattractants in their environment are of central importance for the innate immunity. Neutrophils are guided towards sites of inflammation following the activation of G-protein coupled chemoattractant receptors such as CXCR2 whose signaling strongly depends on the activity of Ca2+ permeable TRPC6 channels. It is the aim of this study to analyze data sets obtained in vitro (murine neutrophils) and in vivo (zebrafish neutrophils) with a stochastic mathematical model to gain deeper insight into the underlying mechanisms. The model is based on the analysis of trajectories of individual neutrophils. Bayesian data analysis, including the covariances of positions for fractional Brownian motion as well as for exponentially and power-law tempered model variants, allows the estimation of parameters and model selection. Our model-based analysis reveals that wildtype neutrophils show pure superdiffusive fractional Brownian motion. This so-called anomalous dynamics is characterized by temporal long-range correlations for the movement into the direction of the chemotactic CXCL1 gradient. Pure superdiffusion is absent vertically to this gradient. This points to an asymmetric 'memory' of the migratory machinery, which is found both in vitro and in vivo. CXCR2 blockade and TRPC6-knockout cause tempering of temporal correlations in the chemotactic gradient. This can be interpreted as a progressive loss of memory, which leads to a marked reduction of chemotaxis and search efficiency of neutrophils. In summary, our findings indicate that spatially differential regulation of anomalous dynamics appears to play a central role in guiding efficient chemotactic behavior.
    Keywords Biology (General) ; QH301-705.5
    Subject code 612
    Language English
    Publishing date 2022-05-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: DnaJ-PKAc fusion induces liver inflammation in a zebrafish model of fibrolamellar carcinoma

    Sofia de Oliveira / Ruth A. Houseright / Benjamin G. Korte / Anna Huttenlocher

    Disease Models & Mechanisms, Vol 13, Iss

    2020  Volume 4

    Abstract: Fibrolamellar carcinoma (FLC) is a rare liver cancer that affects adolescents and young adults. Genomic analysis of FLC has revealed a 400 kb deletion in chromosome 19 that leads to the chimeric transcript DNAJB1-PRKACA (DnaJ-PKAc), comprised of the ... ...

    Abstract Fibrolamellar carcinoma (FLC) is a rare liver cancer that affects adolescents and young adults. Genomic analysis of FLC has revealed a 400 kb deletion in chromosome 19 that leads to the chimeric transcript DNAJB1-PRKACA (DnaJ-PKAc), comprised of the first exon of heat shock protein 40 (DNAJB1) and exons 2-10 of the catalytic subunit of protein kinase A (PRKACA). Here, we report a new zebrafish model of FLC induced by ectopic expression of zebrafish Dnaja-Pkaca (zfDnaJa-Pkaca) in hepatocytes that is amenable to live imaging of early innate immune inflammation. Expression of zfDnaJa-Pkaca in hepatocytes induces hepatomegaly and increased hepatocyte size. In addition, FLC larvae exhibit early innate immune inflammation characterized by early infiltration of neutrophils and macrophages into the liver microenvironment. Increased Caspase-a (the zebrafish homolog for human caspase-1) activity was also found in the liver of FLC larvae, and pharmacological inhibition of Tnfα and caspase-a decreased liver size and inflammation. Overall, these findings show that innate immune inflammation is an early feature in a zebrafish model of FLC and that pharmacological inhibition of TNFα or caspase-1 activity might be targets to treat inflammation and progression in FLC patients. This article has an associated First Person interview with the first author of the paper.
    Keywords fibrolamellar carcinoma ; liver ; inflammation ; early progression ; non-invasive imaging ; Medicine ; R ; Pathology ; RB1-214
    Subject code 616
    Language English
    Publishing date 2020-04-01T00:00:00Z
    Publisher The Company of Biologists
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: Live imaging and gene expression analysis in zebrafish identifies a link between neutrophils and epithelial to mesenchymal transition.

    Christina M Freisinger / Anna Huttenlocher

    PLoS ONE, Vol 9, Iss 11, p e

    2014  Volume 112183

    Abstract: Chronic inflammation is associated with epithelial to mesenchymal transition (EMT) and cancer progression however the relationship between inflammation and EMT remains unclear. Here, we have exploited zebrafish to visualize and quantify the earliest ... ...

    Abstract Chronic inflammation is associated with epithelial to mesenchymal transition (EMT) and cancer progression however the relationship between inflammation and EMT remains unclear. Here, we have exploited zebrafish to visualize and quantify the earliest events during epithelial cell transformation induced by oncogenic HRas(V12). Live imaging revealed that expression of HRas(V12) in the epidermis results in EMT and chronic neutrophil and macrophage infiltration. We have developed an in vivo system to probe and quantify gene expression changes specifically in transformed cells from chimeric zebrafish expressing oncogenic HRas(V12) using translating ribosomal affinity purification (TRAP). We found that the expression of genes associated with EMT, including slug, vimentin and mmp9, are enriched in HRas(V12) transformed epithelial cells and that this enrichment requires the presence of neutrophils. An early signal induced by HRas(V12) in epithelial cells is the expression of il-8 (cxcl8) and we found that the chemokine receptor, Cxcr2, mediates neutrophil but not macrophage recruitment to the transformed cells. Surprisingly, we also found a cell autonomous role for Cxcr2 signaling in transformed cells for both neutrophil recruitment and EMT related gene expression associated with Ras transformation. Taken together, these findings implicate both autocrine and paracrine signaling through Cxcr2 in the regulation of inflammation and gene expression in transformed epithelial cells.
    Keywords Medicine ; R ; Science ; Q
    Subject code 570
    Language English
    Publishing date 2014-01-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Article ; Online: Aspergillus fumigatus transcription factor ZfpA regulates hyphal development and alters susceptibility to antifungals and neutrophil killing during infection.

    Taylor J Schoen / Dante G Calise / Jin Woo Bok / Morgan A Giese / Chibueze D Nwagwu / Robert Zarnowski / David Andes / Anna Huttenlocher / Nancy P Keller

    PLoS Pathogens, Vol 19, Iss 5, p e

    2023  Volume 1011152

    Abstract: Hyphal growth is essential for host colonization during Aspergillus infection. The transcription factor ZfpA regulates A. fumigatus hyphal development including branching, septation, and cell wall composition. However, how ZfpA affects fungal growth and ... ...

    Abstract Hyphal growth is essential for host colonization during Aspergillus infection. The transcription factor ZfpA regulates A. fumigatus hyphal development including branching, septation, and cell wall composition. However, how ZfpA affects fungal growth and susceptibility to host immunity during infection has not been investigated. Here, we use the larval zebrafish-Aspergillus infection model and primary human neutrophils to probe how ZfpA affects A. fumigatus pathogenesis and response to antifungal drugs in vivo. ZfpA deletion promotes fungal clearance and attenuates virulence in wild-type hosts and this virulence defect is abrogated in neutrophil-deficient zebrafish. ZfpA deletion also increases susceptibility to human neutrophils ex vivo while overexpression impairs fungal killing. Overexpression of ZfpA confers protection against the antifungal caspofungin by increasing chitin synthesis during hyphal development, while ZfpA deletion reduces cell wall chitin and increases caspofungin susceptibility in neutrophil-deficient zebrafish. These findings suggest a protective role for ZfpA activity in resistance to the innate immune response and antifungal treatment during A. fumigatus infection.
    Keywords Immunologic diseases. Allergy ; RC581-607 ; Biology (General) ; QH301-705.5
    Subject code 572
    Language English
    Publishing date 2023-05-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  5. Article ; Online: Cxcr1 mediates recruitment of neutrophils and supports proliferation of tumor-initiating astrocytes in vivo

    Davalyn Powell / Meng Lou / Francisco Barros Becker / Anna Huttenlocher

    Scientific Reports, Vol 8, Iss 1, Pp 1-

    2018  Volume 12

    Abstract: Abstract Neutrophils are first-responders to sites of infection and tissue damage including the inflamed tumor microenvironment. Increasing evidence suggests that crosstalk between tumors and neutrophils can affect the progression of established tumors. ... ...

    Abstract Abstract Neutrophils are first-responders to sites of infection and tissue damage including the inflamed tumor microenvironment. Increasing evidence suggests that crosstalk between tumors and neutrophils can affect the progression of established tumors. However, there is a gap in our understanding of the early events that lead to neutrophil recruitment to oncogene-transformed cells and how these pathways alter tumor progression. Here, we use optically transparent zebrafish larvae to probe the early signals that mediate neutrophil recruitment to Kras-transformed astrocytes. We show that zebrafish larvae with impaired neutrophil function exhibit reduced proliferation of transformed astrocytes supporting a critical role for tumor-associated neutrophils in the early progression of tumorigenesis. Moreover, using mutants and pharmacological inhibition, we show that the chemokine receptor Cxcr1 promotes neutrophil recruitment, proliferation of tumor-initiating cells, and neoplastic mass formation. These findings highlight the power of the larval zebrafish system to image and probe early events in the tumor-initiating microenvironment and demonstrate the potential for neutrophil recruitment signaling pathways such as Cxcl8-Cxcr1 as targets for anti-cancer therapies.
    Keywords Medicine ; R ; Science ; Q
    Subject code 571
    Language English
    Publishing date 2018-09-01T00:00:00Z
    Publisher Nature Publishing Group
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article: Real-time visualization of immune cell clearance of Aspergillus fumigatus spores and hyphae

    Knox, Benjamin P / Anna Huttenlocher / Nancy P. Keller

    Fungal genetics and biology. 2017 Aug., v. 105

    2017  

    Abstract: Invasive aspergillosis (IA) is a disease of the immunocompromised host and generally caused by the opportunistic fungal pathogen Aspergillus fumigatus. While both host and fungal factors contribute to disease severity and outcome, there are fundamental ... ...

    Abstract Invasive aspergillosis (IA) is a disease of the immunocompromised host and generally caused by the opportunistic fungal pathogen Aspergillus fumigatus. While both host and fungal factors contribute to disease severity and outcome, there are fundamental features of IA development including fungal morphological transition from infectious conidia to tissue-penetrating hyphae as well as host defenses rooted in mechanisms of innate phagocyte function. Here we address recent advances in the field and use real-time in vivo imaging in the larval zebrafish to visually highlight conserved vertebrate innate immune behaviors including macrophage phagocytosis of conidia and neutrophil responses post-germination.
    Keywords aspergillosis ; Aspergillus fumigatus ; conidia ; Danio rerio ; disease severity ; fungi ; hyphae ; image analysis ; larvae ; macrophages ; neutrophils ; pathogens ; phagocytosis ; vertebrates
    Language English
    Dates of publication 2017-08
    Size p. 52-54.
    Publishing place Elsevier Inc.
    Document type Article
    ZDB-ID 1319820-8
    ISSN 1096-0937 ; 1087-1845 ; 0147-5975
    ISSN (online) 1096-0937
    ISSN 1087-1845 ; 0147-5975
    DOI 10.1016/j.fgb.2017.05.005
    Database NAL-Catalogue (AGRICOLA)

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  7. Article ; Online: Neutrophil Reverse Migration Becomes Transparent with Zebrafish

    Taylor W. Starnes / Anna Huttenlocher

    Advances in Hematology , Vol

    2012  Volume 2012

    Keywords Diseases of the blood and blood-forming organs ; RC633-647.5 ; Specialties of internal medicine ; RC581-951 ; Internal medicine ; RC31-1245 ; Medicine ; R ; DOAJ:Internal medicine ; DOAJ:Medicine (General) ; DOAJ:Health Sciences
    Language English
    Publishing date 2012-01-01T00:00:00Z
    Publisher Hindawi Publishing Corporation
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article ; Online: Generation of Human Neutrophils from Induced Pluripotent Stem Cells in Chemically Defined Conditions Using ETV2 Modified mRNA

    Aditi Majumder / Kran Suknuntha / David Bennin / Lucas Klemm / Vera S. Brok-Volchanskaya / Anna Huttenlocher / Igor Slukvin

    STAR Protocols, Vol 1, Iss 2, Pp 100075- (2020)

    2020  

    Abstract: Summary: This protocol describes a rapid and efficient feeder-, serum-, and xeno-free method for neutrophil generation from hiPSCs using ETV2 modified mRNA (mmRNA), which directs hematoendothelial programming of hiPSCs. Hematoendothelial progenitors were ...

    Abstract Summary: This protocol describes a rapid and efficient feeder-, serum-, and xeno-free method for neutrophil generation from hiPSCs using ETV2 modified mRNA (mmRNA), which directs hematoendothelial programming of hiPSCs. Hematoendothelial progenitors were cultured with GM-CSF, FGF-2, and UM171 to expand myelomonocytic progenitors, followed by treatment with G-CSF and retinoic acid agonist Am580 to induce neutrophil maturation. This protocol is suitable for generating functional neutrophils from iPSCs to interrogate the role of genes in a neutrophil development and function.For complete details on the use and execution of this protocol, please refer to Brok-Volchanskaya et al. (2019).
    Keywords Science (General) ; Q1-390
    Language English
    Publishing date 2020-09-01T00:00:00Z
    Publisher Elsevier
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article ; Online: Cell type specific gene expression profiling reveals a role for complement component C3 in neutrophil responses to tissue damage

    Ruth A. Houseright / Emily E. Rosowski / Pui-Ying Lam / Sebastien J. M. Tauzin / Oscar Mulvaney / Colin N. Dewey / Anna Huttenlocher

    Scientific Reports, Vol 10, Iss 1, Pp 1-

    2020  Volume 15

    Abstract: Abstract Tissue damage induces rapid recruitment of leukocytes and changes in the transcriptional landscape that influence wound healing. However, the cell-type specific transcriptional changes that influence leukocyte function and tissue repair have not ...

    Abstract Abstract Tissue damage induces rapid recruitment of leukocytes and changes in the transcriptional landscape that influence wound healing. However, the cell-type specific transcriptional changes that influence leukocyte function and tissue repair have not been well characterized. Here, we employed translating ribosome affinity purification (TRAP) and RNA sequencing, TRAP-seq, in larval zebrafish to identify genes differentially expressed in neutrophils, macrophages, and epithelial cells in response to wounding. We identified the complement pathway and c3a.1, homologous to the C3 component of human complement, as significantly increased in neutrophils in response to wounds. c3a.1 −/− zebrafish larvae have impaired neutrophil directed migration to tail wounds with an initial lag in recruitment early after wounding. Moreover, c3a.1 −/− zebrafish larvae have impaired recruitment to localized bacterial infections and reduced survival that is, at least in part, neutrophil mediated. Together, our findings support the power of TRAP-seq to identify cell type specific changes in gene expression that influence neutrophil behavior in response to tissue damage.
    Keywords Medicine ; R ; Science ; Q
    Subject code 571
    Language English
    Publishing date 2020-09-01T00:00:00Z
    Publisher Nature Publishing Group
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  10. Article ; Online: Chemokine Signaling and the Regulation of Bidirectional Leukocyte Migration in Interstitial Tissues

    Davalyn Powell / Sebastien Tauzin / Laurel E. Hind / Qing Deng / David J. Beebe / Anna Huttenlocher

    Cell Reports, Vol 19, Iss 8, Pp 1572-

    2017  Volume 1585

    Abstract: Motile cells navigate through complex tissue environments that include both attractive and repulsive cues. In response to tissue wounding, neutrophils, primary cells of the innate immune response, exhibit bidirectional migration that is orchestrated by ... ...

    Abstract Motile cells navigate through complex tissue environments that include both attractive and repulsive cues. In response to tissue wounding, neutrophils, primary cells of the innate immune response, exhibit bidirectional migration that is orchestrated by chemokines and their receptors. Although progress has been made in identifying signals that mediate the recruitment phase, the mechanisms that regulate neutrophil reverse migration remain largely unknown. Here, we visualize bidirectional neutrophil migration to sterile wounds in zebrafish larvae and identify specific roles for the chemokine receptors Cxcr1 and Cxcr2 in neutrophil recruitment to sterile injury and infection. Notably, we also identify Cxcl8a/Cxcr2 as a specific ligand-receptor pair that orchestrates neutrophil chemokinesis in interstitial tissues during neutrophil reverse migration and resolution of inflammation. Taken together, our findings identify distinct receptors that mediate bidirectional leukocyte motility during interstitial migration depending on the context and type of tissue damage in vivo.
    Keywords chemotaxis ; chemokinesis ; reverse migration ; Cxcr1 ; Cxcr2 ; IL-8 ; fugetaxis ; wound ; Biology (General) ; QH301-705.5
    Subject code 571
    Language English
    Publishing date 2017-05-01T00:00:00Z
    Publisher Elsevier
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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