Mouse models of thrombosis: thrombomodulin

SummaryThis review describes animal models of TM-deficiency that cause thrombosis in mice. Thrombomodulin (TM) is a key component of the protein C anticoagulant pathway by facilitating the activation of protein C by thrombin. In addition, TM integrates fibrinolytic and anti-inflammatory responses in a manner that is in part independent of protein C and thrombin. A series of genetically modified mouse strains is available in which the various and distinct functions of TM have been altered by means of site-directed mutagenesis of the TM gene locus (Thbd). The focus of the current review is the pathological activation of the hemostatic mechanism in mice with altered TM function (the pathologic activation of the hemostatic mechanism). The analysis of these mouse models has revealed novel and in part organ-specific functions of TM, most notably in the vascular bed of the placenta. In these mouse models, the severity and phenotypic expression of thrombosis is highly variable and is dependent on interaction with secondary genetic or environmental modifiers. The mutant mouse strains replicate important aspects of thrombophilia and thrombosis in humans, and provide a valuable resource to validate existing, and develop novel concepts of disease mechanisms in human patients.

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Mouse models of neurodegeneration: Know your question, know your mouse

Science Translational Medicine ◽

10.1126/scitranslmed.aaq1818 ◽

2019 ◽

Vol 11 (493) ◽

pp. eaaq1818 ◽

Cited By ~ 9

Author(s):

Elizabeth M. C. Fisher ◽

David M. Bannerman

Keyword(s):

Neurodegenerative Disease ◽

Mouse Models ◽

Mutant Mouse ◽

Mouse Strains ◽

Disease Mechanisms ◽

Research Questions

Many mutant mouse strains have been developed as models to investigate neurodegenerative disease in humans. However, variability in results among studies using these mouse strains has led to questions about the value of these models. Here, we appraise various mouse models for dissecting neurodegenerative disease mechanisms and emphasize the importance of asking appropriate research questions. In therapeutic studies, we suggest that understanding variability among and within mouse models is crucial for preventing translational failures in human patients.

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Use of mouse models to investigate the contributions of CNVs associated with schizophrenia and autism to disease mechanisms

Current Opinion in Genetics & Development ◽

10.1016/j.gde.2021.03.004 ◽

2021 ◽

Vol 68 ◽

pp. 99-105

Author(s):

Steven E Hyman

Keyword(s):

Mouse Models ◽

Disease Mechanisms

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IMMU-22. THE IMPACT OF MICROGLIA MODULATION ON GBM PROGRESSION IN SYNGENEIC MOUSE MODELS

Neuro-Oncology ◽

10.1093/neuonc/noab196.381 ◽

2021 ◽

Vol 23 (Supplement_6) ◽

pp. vi96-vi96

Author(s):

Marie-Françoise Ritz ◽

Tala Shekarian ◽

Tomás A Martins ◽

Philip Schmassmann ◽

Gregor Hutter

Keyword(s):

Mouse Models ◽

Tumor Development ◽

Adaptive Immune Response ◽

Tamoxifen Treatment ◽

Mouse Strains ◽

Intracerebral Injection ◽

Adaptive Immune ◽

Tumor Immune Microenvironment ◽

The Impact

Abstract BACKGROUND The tumor immune microenvironment (TME) of Glioblastoma consists of almost myeloid-derived macrophages and microglia called TAMs. We have shown that the disruption of CD47-Sirpα-axis induces an antitumor activity of TAMs against GBM in immune-deficient mice, through increases of phagocytosis of tumor cells by TAMs. We have aimed to study the role of microglia and its activation/depletion on GBM progression, in the syngeneic GBM model in immune-competent mice. We have studied the interplay of innate and adaptive immune response after activation and depletion of microglia and the effect on tumor progression and outcome of the mice. MATERIAL AND METHODS We used different colonies of genetically modified immunocompetent mouse strains to genetically activate/deplete microglia in the tumor context. We generated Sall1 CreERT2/fl mice and Cre-negative littermates. The application of Tamoxifen in this constellation leads to the excision of the transcription factor Sall1 and subsequent enhanced microglia activity. Conversely, we generated Sall1 CreERT2 x Csf1r fl/fl animals and the respective heterozygous and Cre-negative littermates in which Tamoxifen treatment leads to inactivation of microglia through the deletion of Csf1r. Glioblastoma tumors were induced by intracerebral injection of GL261, CT2A, or retrovirus-induced PDGF-Akt in pups and Tamoxifen treatment was started once the tumors were detected. RESULTS We observed a survival advantage in tumor-bearing mice after activation of microglia in Sall1 CreERT/fl animals compared to Cre-negative littermates. Genetic depletion of microglia in this model resulted in a shorter lifespan in microglia-depleted animals compared to Cre-negative littermates. Furthermore, the iTME in these tumors is subjected to scRNAseq analysis to identify mechanistic insights. CONCLUSION Microglia are important players in tumor development and progression of glioblastoma in mouse models. These cells may be targeted in future immunotherapeutic approaches for patients.

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Influence of the Bcg Locus on Natural Resistance to Primary Infection with the Facultative Intracellular Bacterium Francisella tularensis in Mice

Infection and Immunity ◽

10.1128/iai.68.3.1480-1484.2000 ◽

2000 ◽

Vol 68 (3) ◽

pp. 1480-1484 ◽

Cited By ~ 13

Author(s):

Hana Kovářová ◽

Lenka Hernychová ◽

Marián Hajdúch ◽

M. Šírová ◽

Aleš Macela

Keyword(s):

Francisella Tularensis ◽

Bacterial Colonization ◽

Phenotypic Expression ◽

Interleukin 10 ◽

Natural Resistance ◽

Mouse Strains ◽

Oxygen Intermediates ◽

Necrosis Factor Alpha ◽

Factor Alpha ◽

Resistance To Infection

ABSTRACT The implication of the Bcg locus in the control of natural resistance to infection with a live vaccine strain (LVS) of the intracellular pathogen Francisella tularensis was studied. Analysis of phenotypic expression of natural resistance and susceptibility was performed using mouse strains congenic at theBcg locus. Comparison of the kinetics of bacterial colonization of spleen showed that B10.A.Bcg(r) mice were extremely susceptible during early phases of primary sublethal infection, while their congenic C57BL/10N [Bcg(s)] counterparts could be classified as resistant to F. tularensis LVS infection according to the 2-log-lower bacterial CFU within the tissue as long as 5 days after infection. Different phenotypes of Bcg congenic mice were associated with differential expression of the cytokines tumor necrosis factor alpha, interleukin-10, and gamma interferon and production of reactive oxygen intermediates. These results strongly suggest that the Bcglocus, which is close or identical to the Nramp1 gene, controls natural resistance to infection by F. tularensisand that its effect is the opposite of that observed for otherBcg-controlled pathogens.

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Modeling Rare Human Disorders in Mice: The Finnish Disease Heritage

Cells ◽

10.3390/cells10113158 ◽

2021 ◽

Vol 10 (11) ◽

pp. 3158

Author(s):

Tomáš Zárybnický ◽

Anne Heikkinen ◽

Salla M. Kangas ◽

Marika Karikoski ◽

Guillermo Antonio Martínez-Nieto ◽

...

Keyword(s):

Human Physiology ◽

Animal Models ◽

Mouse Models ◽

Rare Diseases ◽

Disease Modeling ◽

Common Disease ◽

Molecular Pathways ◽

Finnish Population ◽

Disease Mechanisms ◽

Human Disorders

The modification of genes in animal models has evidently and comprehensively improved our knowledge on proteins and signaling pathways in human physiology and pathology. In this review, we discuss almost 40 monogenic rare diseases that are enriched in the Finnish population and defined as the Finnish disease heritage (FDH). We will highlight how gene-modified mouse models have greatly facilitated the understanding of the pathological manifestations of these diseases and how some of the diseases still lack proper models. We urge the establishment of subsequent international consortiums to cooperatively plan and carry out future human disease modeling strategies. Detailed information on disease mechanisms brings along broader understanding of the molecular pathways they act along both parallel and transverse to the proteins affected in rare diseases, therefore also aiding understanding of common disease pathologies.

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Generation, quality control, and analysis of the first genomically humanised knock-in mice for the ALS/FTD genes SOD1, TARDBP (TDP-43), and FUS

10.1101/2021.07.05.451113 ◽

2021 ◽

Author(s):

Anny Devoy ◽

Georgia Price ◽

Francesca De Giorgio ◽

Rosie Bunton-Stasyshyn ◽

David Thompson ◽

...

Keyword(s):

Quality Control ◽

Mouse Models ◽

Splice Variants ◽

Region Of Interest ◽

Human Protein ◽

Mouse Strains ◽

Coding Region ◽

Protein Biochemistry ◽

Oxford Nanopore

Amyotrophic lateral sclerosis - frontotemporal dementia spectrum disorder (ALS/FTD) is a complex neurodegenerative disease; up to 10% of cases are familial, usually arising from single dominant mutations in >30 causative genes. Transgenic mouse models that overexpress human ALS/FTD causative genes have been the preferred organism for in vivo modelling. However, while conferring human protein biochemistry, these overexpression models are not ideal for dosage-sensitive proteins such as TDP-43 or FUS. We have created three next-generation genomically humanised knock-in mouse models for ALS/FTD research, by replacing the entire mouse coding region of Sod1, Tardbp (TDP-43) and Fus, with their human orthologues to preserve human protein biochemistry, with exons and introns intact to enable future modelling of coding or non-coding mutations and variants and to preserve human splice variants. In generating these mice, we have established a new-standard of quality control: we demonstrate the utility of indirect capture for enrichment of a region of interest followed by Oxford Nanopore sequencing for robustly characterising large knock-in alleles. This approach confirmed that targeting occurred at the correct locus and to map homologous recombination events. Furthermore, extensive expression data from the three lines shows that homozygous humanised animals only express human protein, at endogenous levels. Characterisation of humanised FUS animals showed that they are phenotypically normal compared to wildtype littermates throughout their lifespan. These humanised mouse strains are critically needed for preclinical assessment of interventions, such as antisense oligonucleotides (ASOs), to modulate expression levels in patients, and will serve as templates for the addition of human ALS/FTD mutations to dissect disease pathomechanisms.

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No audible wheezing

Journal of Experimental Medicine ◽

10.1084/jem.20050584 ◽

2005 ◽

Vol 201 (12) ◽

pp. 1869-1873 ◽

Cited By ~ 62

Author(s):

Joshua A. Boyce ◽

K. Frank Austen

Keyword(s):

Mast Cells ◽

Mouse Models ◽

Airway Hyperresponsiveness ◽

Pulmonary Inflammation ◽

Genetic Differences ◽

Mouse Strains ◽

T Helper ◽

Th2 Cell ◽

Helper Type

Mouse models of T helper type 2 (Th2) cell–biased pulmonary inflammation have elucidated mechanisms of sensitization, cell traffic, and induced airway hyperresponsiveness (AHR). Nonetheless, most mice lack intrinsic AHR, a central property of human asthma, and disparities persist regarding the contributions of eosinophils and mast cells and the sensitivity to induced AHR in the commonly used mouse strains. We suggest that these discordances, reflecting methodological and genetic differences, may be informative for understanding heterogeneity of human asthma.

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Thrombin-activatable procarboxypeptidase B regulates activated complement C5a in vivo

Blood ◽

10.1182/blood-2006-03-012567 ◽

2006 ◽

Vol 109 (5) ◽

pp. 1992-1997 ◽

Cited By ~ 38

Author(s):

Toshihiko Nishimura ◽

Timothy Myles ◽

Adrian M. Piliposky ◽

Peter N. Kao ◽

Gerald J. Berry ◽

...

Keyword(s):

Beneficial Effect ◽

Inflammatory Mediators ◽

Protein C ◽

Inflammatory Responses ◽

Cell Counts ◽

Fibrinolysis Inhibitor ◽

Complement C5a ◽

Homeostatic Response ◽

Deficient Mice

Abstract Plasma procarboxypeptidase B (proCPB) is activated by the endothelial thrombin-prothrombomodulin complex. Activated (CPB) functions as a fibrinolysis inhibitor, but it may play a broader role by inactivating inflammatory mediators. To test this hypothesis, C5a-induced alveolitis was studied in wild-type (WT) and proCPB-deficient mice (proCPB−/−). C5a-induced alveolitis, as measured by cell counts and total protein contents in bronchoalveolar lavage fluids, was markedly enhanced in the proCPB−/− mice. E229K thrombin, a thrombin mutant with minimal clotting activity but retaining its ability to activate protein C and proCPB, attenuated C5a-induced alveolitis in WT but not in proCPB−/− mice, indicating that its beneficial effect is mediated primarily by its activation of proCPB. Lung tissue histology confirmed these cellular inflammatory responses. Delayed administration of E229K thrombin after the C5a instillation was ineffective in reducing alveolitis in WT mice, suggesting that the beneficial effect of E229K thrombin is due to the direct inhibition of C5a by CPB. Our studies show that thrombin-activatable proCPB, in addition to its role in fibrinolysis, has intrinsic anti-inflammatory functions. Its activation, along with protein C, by the endothelial thrombin-TM complex represents a homeostatic response to counteract the inflammatory mediators generated at the site of vascular injury.

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Opposing functions of β-arrestin 1 and 2 in Parkinson’s disease via microglia inflammation and Nprl3

10.21203/rs.3.rs-24932/v1 ◽

2020 ◽

Author(s):

Yinquan Fang ◽

Qingling Jiang ◽

Shanshan Li ◽

Hong Zhu ◽

Xiao Ding ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Mouse Models ◽

Inflammatory Responses ◽

Microglia Activation ◽

Loss Of Function ◽

Neuron Loss ◽

Primary Mouse ◽

The Impact

Abstract Background Although β-arrestins (ARRBs) regulate diverse physiological and pathophysiological processes, their function and regulation in Parkinson’s disease (PD) remain poorly defined. Methods We measured expression of ARRB1 and ARRB2 in liposaccharide (LPS)-induced and 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-induced PD mice. ARRB1-deficient and ARRB2-deficient mouse were used to assess the impact of ARRBs on dopaminergic (DA) neuron loss and microglia activation in PD mouse models. After primary mouse DA neurons were exposed to the conditioned medium from ARRB1 knockdown or ARRB2 knockout microglia stimulated by LPS plus interferon γ (IFN-γ), the degeneration of DA neurons was quantified. Gain- and loss-of-function studies were used to study the effects of ARRBs on microglia activation in vitro. To further understand the mechanism, we measured the activation of classical inflammatory pathways and used RNA sequencing to identify the novel downstream effector of ARRBs. Result In this study, we demonstrate that expression of ARRB1 and ARRB2, particularly in microglia, is reciprocally regulated in PD mouse models. ARRB1 ablation ameliorates, whereas ARRB2 knockout aggravates, the pathological features of PD, including DA neuron loss, neuroinflammation and microglia activation in vivo, as well as microglia-mediated neuron damage and inflammation in vitro. In parallel, ARRB1 and ARRB2 produce adverse effects on the activation of inflammatory signal transducers and activators of transcription 1 (STAT1) and nuclear factor-κB (NF-κB) pathways in microglia. We also show that two ARRBs competitively interact with activated p65 in the NF-κB pathway and that nitrogen permease regulator-like 3 (Nprl3), a functionally poorly characterized protein, is a novel effector acting downstream of both ARRBs. Conclusion Collectively, these data demonstrate that two closely related ARRBs have completely opposite functions in microglia-mediated inflammatory responses, via Nprl3, and differentially affect the pathogenesis of PD, and suggest a potential therapeutic strategy.

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