Publications by authors named "Zachary Freeman"

Immune tolerance mechanisms are shared in cancer and pregnancy. Through cross-analyzing single-cell RNA-sequencing data from multiple human cancer types and the maternal-fetal interface, we found B7-H4 (VTCN1) is an onco-fetal immune tolerance checkpoint. We showed that genetic deficiency of B7-H4 resulted in immune activation and fetal resorption in allogeneic pregnancy models.

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Improved diagnostic capabilities and a desire to reduce or refine the use of animals as soiled bedding sentinels (SBS) have driven interest in developing the use of PCR-based testing methods, such as exhaust dust testing (EDT), for routine rodent health surveillance. We compared the absolute and quantitative PCR results from EDT filters with SBS mice by routine screening via a panel of 19 infectious agents including agents known to be excluded or present in the colony. In this study, EDT and SBS were compared at days 0, 90, and 180 in 3 facilities ( = 12 rooms) with animals housed on IVC racks ( = 19 double-sided and 23 single-sided racks).

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NOD.Cg-/SzJ (NSG) mice, lacking many components of a mature immune system, are at increased risk of disease. General understanding of potential pathogens of these mice is limited.

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Article Synopsis
  • To understand COVID-19, it's essential to study all hosts of SARS-CoV-2, leading to the identification of 37 natural and 19 laboratory hosts classified as therian mammals.
  • The analysis revealed that specific mouse models with genetically modified human proteins are particularly susceptible to coronaviruses, highlighting the importance of these proteins in viral severity.
  • The study proposes a MOVIE model to explain the virus's variations and immune evasion in animal hosts, which might have influenced the COVID-19 pandemic's progression.
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Introduction: C3 is central for all complement activation pathways, thus making it an attractive therapeutic target. Many C3-targeted agents are under extensive development with one already approved for clinical use. However, most, if not all, C3 inhibitors are human or nonhuman primate C3-specific, making evaluating their efficacies in vivo before a clinical trial extremely difficult and costly.

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Mice have become increasingly popular as genetic tools, facilitated by the production of advanced genetically engineered mouse models (GEMMs). GEMMs often require in-house breeding and production by research groups, which can be quite complex depending on the design of the GEMM. Identification of methods to increase the efficiency of breeding practices offers opportunities to optimize and reduce the number of animals bred for research while maintaining similar research output.

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Macaques with self-injurious behavior (SIB) have been used as a model of human SIB and have previously been shown to respond to treatments targeting enhancement of central serotonin signaling, whether by supplementation with tryptophan, or by inhibiting synaptic reuptake. Decreased serotonin signaling in the brain has also been implicated in many human psychopathologies including major depression disorder. A disturbance in tryptophan metabolism that moves away from the production of serotonin and toward the production of kynurenine has been proposed as a major etiological factor of depression.

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Chronic vascular access devices are widely used in a variety of species for repeated blood sampling or substance administration. Jugular catheters are commonly used for studying addiction-related behaviors in rats. Rats with catheters have historically been individually housed for the duration of the study to prevent cage mates from damaging the catheter.

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The combination of bedding substrate and nesting material within the microenvironment of mice is an important consideration for animal care programs in regard to optimizing animal wellbeing. We used 3 general or breeding mouse colonies in our institution to evaluate the effects of bedding substrate on nest building, breeding performance, and recognition of animal health concerns. A scoring system was developed to assess the incorporation of bedding into the nest cup base and walls (nest base incorporation, NBI) in a controlled study with mice bedded on either compressed paper (CP) or corncob (CC) bedding.

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Immunocompromised mouse strains expressing human transgenes are being increasingly used in biomedical research. The genetic modifications in these mice cause various cellular responses, resulting in histologic features unique to each strain. The NSG-SGM3 mouse strain is similar to the commonly used NSG (NOD gamma) strain but expresses human transgenes encoding stem cell factor (also known as KIT ligand), granulocyte-macrophage colony-stimulating factor, and interleukin 3.

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Bedding material is a critical component of the mouse environment and affects animal wellbeing and research integrity. Corn cob (CC) bedding has been a common bedding choice in research despite several potential negative aspects of its use. We investigated the use of compressed paper (CP) bedding as a refinement to CC bedding.

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Despite the increasing popularity of zebrafish () as an animal model, the environmental enrichment preferences of this species have been largely unexplored. We sought to determine the preferences of mature female zebrafish that were singly housed with or without access to one of 10 inanimate forms of enrichment. As a marker of preference, in-tank fish location was observed by video recording.

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Despite advancements in targeting the immune checkpoints program cell death protein 1 (PD-1), programmed death ligand 1 (PD-L1), and cytotoxic T lymphocyte-associated protein 4 (CTLA-4) for cancer immunotherapy, a large number of patients and cancer types remain unresponsive. Current immunotherapies focus on modulating an antitumor immune response by directly or indirectly expanding antitumor CD8 T cells. A complementary strategy might involve inhibition of Tregs that otherwise suppress antitumor immune responses.

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Robust preclinical models of ovarian high-grade serous carcinoma (HGSC) are needed to advance our understanding of HGSC pathogenesis and to test novel strategies aimed at improving clinical outcomes for women with the disease. Genetically engineered mouse models of HGSC recapitulating the likely cell of origin (fallopian tube), underlying genetic defects, histology, and biologic behavior of human HGSCs have been developed. However, the degree to which the mouse tumors acquire the somatic genomic changes, gene expression profiles, and immune microenvironment that characterize human HGSCs remains unclear.

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Background: Prostate cancer responds poorly to current immunotherapies. Epigenetic therapies such as BET Bromodomain inhibition can change the transcriptome of tumor cells, possibly making them more immunogenic and thus susceptible to immune targeting.

Methods: We characterized the effects of BET bromodomain inhibition using JQ1 on PD-L1 and HLA-ABC expression in two human prostate cell lines, DU145 and PC3.

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The recommends sanitizing cage components, including microisolation cage tops (MCT), at a minimum of every 2 wk. Previously published data demonstrated that mouse MCT microbial loads do not increase until at least 2 wk and that sanitation can be delayed past 2 wk. How microbial loads differ on mouse compared with rat MCT, as well as across different ventilation systems, remains unclear.

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Floor contamination control practices in rodent housing facilities commonly include disposable shoe covers despite the lack of evidence for their usefulness in bioexclusion. Contamination control flooring mats are advertised as an economical and environmentally-responsible alternative to shoe covers, yet little is published regarding their efficacy in preventing the transfer of organic material and the introduction of infectious agents into facilities. We evaluated 4 floor contamination control strategies-shoe covers (ShCv), contamination control flooring (CCF), using both products concurrently (ShCv+CCF) compared with using neither-in preventing bacterial transfer and reducing organic load on facility floors and maintaining murine colony health status.

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Zibotentan, an endothelin-A receptor antagonist, has been used in the treatment of various cardiovascular disorders and neoplasia. Castrated athymic nude mice receiving zibotentan for a preclinical xenograft efficacy study experienced weight loss, gastrointestinal bloat, and the presence of an audible respiratory click. Human side effects have been reported in the nasal cavity, so we hypothesized that the nasal cavity is a target for toxicity in mice receiving zibotentan.

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Carcinoma-associated mesenchymal stem cells (CA-MSCs) are critical stromal progenitor cells within the tumor microenvironment (TME). We previously demonstrated that CA-MSCs differentially express bone morphogenetic protein family members, promote tumor cell growth, increase cancer "stemness," and chemotherapy resistance. Here, we use RNA sequencing of normal omental MSCs and ovarian CA-MSCs to demonstrate global changes in CA-MSC gene expression.

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Type I IFN production is essential for innate control of acute viral infection; however, prolonged high-level IFN production is associated with chronic immune activation in HIV-infected individuals. Although plasmacytoid DCs (pDCs) are a primary source of IFN, the mechanisms that regulate IFN levels following the acute phase are unknown. We hypothesized that HIV-specific Ab responses regulate late IFN production.

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Unlabelled: Programmed death-1 (PD-1) is a coinhibitory receptor that downregulates the activity of tumor-infiltrating lymphocytes (TIL) in cancer and of virus-specific T cells in chronic infection. The molecular mechanisms driving high PD-1 expression on TILs have not been fully investigated. We demonstrate that TGFβ1 enhances antigen-induced PD-1 expression through SMAD3-dependent, SMAD2-independent transcriptional activation in T cells in vitro and in TILs in vivo The PD-1 subset seen in CD8 TILs is absent in Smad3-deficient tumor-specific CD8 TILs, resulting in enhanced cytokine production by TILs and in draining lymph nodes and antitumor activity.

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Self-injurious behavior (SIB) occurs within laboratory-housed NHP at low frequency but can have a devastating effect on animal research and wellbeing. One barrier to the study and clinical management of these cases is the cost of equipment and personnel time to quantify the behavior according to the current standard of observation and to score remotely obtained video recordings. In studies of human SIB, in which direct observation is difficult or prohibited, researchers have demonstrated that quantifying the tissue damage resulting from SIB can be a useful proxy to represent the underlying behavior.

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