المؤلفون: Deets, Katherine A, Doyle, Randilea Nichols, Rauch, Isabella, Vance, Russell E

مصطلحات موضوعية: Biomedical and Clinical Sciences, Immunology, Rare Diseases, Underpinning research, 1.1 Normal biological development and functioning, Inflammatory and immune system, Good Health and Well Being, Adaptive Immunity, Animals, CD8-Positive T-Lymphocytes, Cross-Priming, Dendritic Cells, Epithelial Cells, Female, Inflammasomes, Intestinal Mucosa, Male, Mice, Mice, Transgenic, Pyroptosis, inflammasome, antigen presentation, intestinal epithelial cells, adaptive immunity, Mouse, immunology, inflammation, mouse, Biochemistry and Cell Biology, Biological sciences, Biomedical and clinical sciences, Health sciences

الوصف: The innate immune system detects pathogens and initiates adaptive immune responses. Inflammasomes are central components of the innate immune system, but whether inflammasomes provide sufficient signals to activate adaptive immunity is unclear. In intestinal epithelial cells (IECs), inflammasomes activate a lytic form of cell death called pyroptosis, leading to epithelial cell expulsion and the release of cytokines. Here, we employed a genetic system to show that simultaneous antigen expression and inflammasome activation specifically in IECs is sufficient to activate CD8+ T cells. By genetic elimination of direct T cell priming by IECs, we found that IEC-derived antigens were cross-presented to CD8+ T cells. However, cross-presentation of IEC-derived antigen to CD8+ T cells only partially depended on IEC pyroptosis. In the absence of inflammasome activation, cross-priming of CD8+ T cells required Batf3+ dendritic cells (conventional type one dendritic cells [cDC1]), whereas cross-priming in the presence of inflammasome activation required a Zbtb46+ but Batf3-independent cDC population. These data suggest the existence of parallel inflammasome-dependent and inflammasome-independent pathways for cross-presentation of IEC-derived antigens.

وصف الملف: application/pdf

الوصول الحر: https://escholarship.org/uc/item/9wz6n9g2Test

المؤلفون: Rauch, Isabella, Deets, Katherine A, Ji, Daisy X, von Moltke, Jakob, Tenthorey, Jeannette L, Lee, Angus Y, Philip, Naomi H, Ayres, Janelle S, Brodsky, Igor E, Gronert, Karsten, Vance, Russell E

المصدر: Immunity. 46(4)

مصطلحات موضوعية: Foodborne Illness, Prevention, Vaccine Related, Digestive Diseases, Biodefense, Emerging Infectious Diseases, Aetiology, 2.1 Biological and endogenous factors, Animals, Apoptosis Regulatory Proteins, Calcium-Binding Proteins, Caspase 1, Caspase 8, Eicosanoids, Enzyme Activation, Enzyme-Linked Immunosorbent Assay, Epithelial Cells, Inflammasomes, Interleukin-18, Intestinal Mucosa, Intracellular Signaling Peptides and Proteins, Mice, Inbred C57BL, Mice, Knockout, Mice, Transgenic, Microscopy, Confocal, Neuronal Apoptosis-Inhibitory Protein, Phosphate-Binding Proteins, Salmonella Infections, Salmonella typhimurium, ASC, Caspase-1, Caspase-8, Naip, Nlrc4, expulsion, extrusion, inflammasome, intestinal epithelial cell, Immunology

الوصف: Intestinal epithelial cells (IECs) form a critical barrier against pathogen invasion. By generation of mice in which inflammasome expression is restricted to IECs, we describe a coordinated epithelium-intrinsic inflammasome response in vivo. This response was sufficient to protect against Salmonella tissue invasion and involved a previously reported IEC expulsion that was coordinated with lipid mediator and cytokine production and lytic IEC death. Excessive inflammasome activation in IECs was sufficient to result in diarrhea and pathology. Experiments with IEC organoids demonstrated that IEC expulsion did not require other cell types. IEC expulsion was accompanied by a major actin rearrangement in neighboring cells that maintained epithelium integrity but did not absolutely require Caspase-1 or Gasdermin D. Analysis of Casp1-/-Casp8-/- mice revealed a functional Caspase-8 inflammasome in vivo. Thus, a coordinated IEC-intrinsic, Caspase-1 and -8 inflammasome response plays a key role in intestinal immune defense and pathology.

وصف الملف: application/pdf

الوصول الحر: https://escholarship.org/uc/item/3st853r8Test

المؤلفون: Deets, Katherine

مصطلحات موضوعية: Immunology, adaptive immunity, antigen presentation, inflammasome, intestinal epithelial cells

الوصف: The innate immune system detects pathogens and initiates adaptive immune responses. Inflammasomes are central components of the innate immune system, but whether inflammasomes provide sufficient signals to activate adaptive immunity is unclear. In this dissertation, I present the work I have done using a genetic mouse model system that allowed me to simultaneously express the model antigen ovalbumin (Ova) and activate the NAIP–NLRC4 inflammasome in specific cells throughout the mouse.Chapter One begins with an introduction to innate and adaptive immunity. I then provide an overview of inflammasome activation, followed by a discussion of what is currently known about how inflammasomes influence adaptive immunity. This section discusses the roles inflammasome-driven lytic cell death (termed pyroptosis) might play in antigen release, evidence for inflammasome activation driving CD4+ and CD8+ T cell responses, and instances where inflammasome activation appears to inhibit adaptive immunity. This chapter closes with evidence for inflammasomes influencing adaptive immunity in vaccines, anti-tumor immunity, and autoimmunity. Overall, Chapter One provides a foundation for appreciating why we need better understanding of the role inflammasome activation plays in driving adaptive immune responses.In Chapter Two, I present my early doctoral work, where I began to explore what role(s) NAIP–NLRC4 inflammasome activation might have on adaptive T cell immunity. Here I introduce the OvaFla mouse model previously, which was described by the Vance lab. These mice use the Cre-Lox system to inducibly express a fusion protein containing Ova antigen and the 166 amino acid C-terminal of flagellin, which will activate NAIP–NLRC4 but not an alternative flagellin sensor called TLR5. For experiments in this chapter, I crossed these “OvaFla” mice with mice containing a tamoxifen-inducible Cre driver, Cre-ERT2, that results in systemic OvaFla expression following tamoxifen administration. I found that systemic OvaFla can drive cross priming of CD8+ T cells in both WT and NLRC4-deficient mice. However, because Cre-ERT2 is expressed throughout the mouse, we remain unsure where and how this cross priming is occurring. I did determine, however, that signaling through the IL-18R on cross presenting cells is not required for CD8+ T cell activation. One potential benefit to the OvaFla Cre-ERT2 system is that localized tamoxifen application can be used to drive a more focused Cre expression. Additionally, bone marrow-derived cells from these mice retain the ability to activate OvaFla, which may be useful for future in vitro studies. In all, the work presented in this chapter provides some initial insights into the OvaFla Cre-ERT2 system, with suggestions on how they may be a useful tool for others. Chapter Three describes the bulk of my doctoral work, which specifically focused on activation of the NAIP–NLRC4 inflammasome in intestinal epithelial cells (IECs). NAIP–NLRC4 activation in these cells results in IEC pyroptosis, followed by an expulsion of the IEC into the intestinal lumen. One of my original hypotheses was that pyroptosis, which is mediated by the pore-forming protein Gasdermin D, provides an opportunity for cytosolic antigen to escape into the underlying lamina propria. In the lamina propria, the antigen is theoretically available to be cross-presented on dendritic cells (DCs), which can then drive antigen-specific CD8+ T cell activation. To test this hypothesis, I crossed the OvaFla mice with the Villin-Cre-ERT2 mice, thereby creating animals where tamoxifen administration results in robust OvaFla expression in IECs. These OvaFla Villin-Cre-ERT2 mice were crossed onto Gasdermin D-, ASC-, and NLRC4-deficient backgrounds. In support of my hypothesis, my work showed that IEC-derived antigens can be cross presented to CD8+ T cells in vivo, but we were surprised to find that this cross presentation occurred in both WT and NLRC4-deficient OvaFla mice. Additionally, Gasdermin D-mediated pyroptosis played only a partial role in CD8+ T cell cross-priming. My project then shifted to understanding whether there were any mechanistic differences in antigen cross-presentation between inflammatory conditions (NLRC4-dependent) and steady state (NLRC4-independent). By using two separate genetic knockout mouse lines, I found that cross presentation of IEC antigens during non-inflammatory conditions (in NLRC4-deficient mice) relies on a subset of classical DCs (cDCs) that require the Batf3 transcription factor (cDC1s)—these findings align with previously published data. However, in the presence of inflammasome activation, a Batf3-independent cDC population (likely cDC2s) can cross present IEC-derived antigen. Altogether, these data provide a better understanding of the complex interactions between IECs, DCs, and CD8+ T cells in the gut.In Chapter Four, I close my dissertation with a discussion on some of the remaining questions generated from my work. These questions center around the mechanism(s) of antigen acquisition functional maturation of the cross presenting cDCs.In all, my dissertation work has provided a stripped-down approach to understanding how inflammasome activation influences adaptive immunity. Unlike previous studies that rely on infection models, the OvaFla system allowed me to selectively activate the NAIP–NLRC4 inflammasome and uncover a Batf3+ cDC1-independent pathway of IEC antigen cross presentation.

وصف الملف: application/pdf

الوصول الحر: https://escholarship.org/uc/item/9kr1829sTest

المؤلفون: Tenthorey, Jeannette L., Chavez, Roberto A., Thompson, Thornton W., Deets, Katherine A., Vance, Russell E., Rauch, Isabella

المساهمون: Oregon Health and Science University, Howard Hughes Medical Institute, National Institutes of Health

المصدر: Journal of Experimental Medicine ; volume 217, issue 7 ; ISSN 0022-1007 1540-9538

الوصف: The NAIP/NLRC4 inflammasome is a cytosolic sensor of bacteria that activates caspase-1 and initiates potent immune responses. Structural, biochemical, and genetic data demonstrate that NAIP proteins are receptors for bacterial ligands, while NLRC4 is a downstream adaptor that multimerizes with NAIPs to form an inflammasome. NLRC4 has also been proposed to suppress tumor growth, though the underlying mechanism is unknown. Further, NLRC4 is phosphorylated on serine 533, which was suggested to be critical for its function. In the absence of S533 phosphorylation, it was proposed that another inflammasome protein, NLRP3, can induce NLRC4 activation. We generated a new Nlrc4-deficient mouse line and mice with S533D phosphomimetic or S533A nonphosphorylatable NLRC4. Using these models in vivo and in vitro, we fail to observe a requirement for phosphorylation in NLRC4 inflammasome function. Furthermore, we find no role for NLRP3 in NLRC4 function, or for NLRC4 in a model of melanoma. These results clarify our understanding of the mechanism and biological functions of NAIP/NLRC4 activation.

الإتاحة: https://doi.org/10.1084/jem.20191736Test

المؤلفون: Higdon, Lauren E., Deets, Katherine A., Friesen, Travis J., Sze, Kai-Yin, Fink, Pamela J.

المصدر: Proceedings of the National Academy of Sciences of the United States of America, 2014 Apr . 111(15), 5652-5657.

الوصول الحر: https://www.jstor.org/stable/23771567Test

المؤلفون: Deets, Katherine, Vance, Russell

الوصف: The innate immune system detects pathogens and initiates adaptive immune responses. Inflammasomes are central components of the innate immune system, but whether inflammasomes provide sufficient signals to activate adaptive immunity is unclear. In intestinal epithelial cells (IECs), inflammasomes activate a lytic form of cell death called pyroptosis, leading to epithelial cell expulsion and the release of cytokines. Here we employed a genetic system to show that simultaneous antigen expression and inflammasome activation specifically in IECs is sufficient to activate CD8+ T cells. By genetic elimination of direct T cell priming by IECs, we found that IEC-derived antigens are cross-presented to CD8+ T cells. However, activation of CD8+ T cells by IEC-derived antigen only partially depended on IEC pyroptosis. In the absence of inflammasome activation, cross-priming of CD8+ T cells required Batf3+ dendritic cells (cDC1), whereas cross-priming in the presence of pyroptosis required a Batf3-independent cDC population. These data suggest the existence of parallel pyroptosis-dependent and pyroptosis-independent but cDC1-dependent pathways for cross-presentation of IEC-derived antigens. ; .czi image files can be opened with Fiji (ImageJ) ; Mice were fed a single day pulse of tamoxifen chow and euthanized two days from start of the chow feeding. Approximately 2.5 cm pieces were taken from the proximal and distal ends of the small intestine. These pieces were flushed and fixed in PLP buffer (0.05 M phosphate buffer containing 0.1 M L-lysine [pH 7.4], 2 mg/mL NaIO4, and 1% PFA) overnight at 4 °C. The following day, tissues were washed 2x in phosphate buffer and placed in 30% sucrose overnight at 4 °C. Tissue was frozen in Tissue-Tek® OCT (VWR; 25608-930), cut on a Leica cryostat, and sections were placed on Fisherbrand™ Tissue Path Superfrost™ Plus Gold Slides (Fisher Scientific; 15-188-48). For staining, slides were allowed to warm to room temperature, traced with an ImmEdge Hydrophobic Barrier Pen (Vector Labs; H-4000), ...

العلاقة: https://zenodo.org/communities/dryadTest; https://zenodo.org/record/5823010Test; https://doi.org/10.6078/D1ST46Test; oai:zenodo.org:5823010

الإتاحة: https://doi.org/10.6078/D1ST46Test
https://doi.org/10.1101/2021.07.08.451636Test
https://doi.org/10.7554/eLife.72082Test
https://zenodo.org/record/5823010Test

المؤلفون: Deets, Katherine A., Vance, Russell E.

المصدر: Nature Immunology ; volume 22, issue 4, page 412-422 ; ISSN 1529-2908 1529-2916

مصطلحات موضوعية: Immunology, Immunology and Allergy

الإتاحة: https://doi.org/10.1038/s41590-021-00869-6Test
https://www.nature.com/articles/s41590-021-00869-6.pdfTest
https://www.nature.com/articles/s41590-021-00869-6Test

المؤلفون: Deets, Katherine A, Nichols Doyle, Randilea, Rauch, Isabella, Vance, Russell E

الإتاحة: https://doi.org/10.7554/elife.72082.sa2Test

المؤلفون: Deets, Katherine A.¹, Doyle, Randilea Nichols¹, Rauch, Isabella², Vance, Russell E.^1,3,4 rvance@berkeley.edu

المصدر: eLife. 12/31/2021, p1-26. 26p.

مصطلحات موضوعية: *EPITHELIAL cells, *INFLAMMASOMES, *ANTIGENS, *CD8 antigen, *CELL death, *DENDRITIC cells, *T cells

مستخلص: The innate immune system detects pathogens and initiates adaptive immune responses. Inflammasomes are central components of the innate immune system, but whether inflammasomes provide sufficient signals to activate adaptive immunity is unclear. In intestinal epithelial cells (IECs), inflammasomes activate a lytic form of cell death called pyroptosis, leading to epithelial cell expulsion and the release of cytokines. Here, we employed a genetic system to show that simultaneous antigen expression and inflammasome activation specifically in IECs is sufficient to activate CD8+ T cells. By genetic elimination of direct T cell priming by IECs, we found that IEC-derived antigens were cross-presented to CD8+ T cells. However, cross-presentation of IEC-derived antigen to CD8+ T cells only partially depended on IEC pyroptosis. In the absence of inflammasome activation, cross-priming of CD8+ T cells required Batf3+ dendritic cells (conventional type one dendritic cells [cDC1]), whereas cross-priming in the presence of inflammasome activation required a Zbtb46+ but Batf3-independent cDC population. These data suggest the existence of parallel inflammasome-dependent and inflammasome-independent pathways for cross-presentation of IEC-derived antigens. [ABSTRACT FROM AUTHOR]

المؤلفون: Deets, Katherine A., Berkley, Amy M., Bergsbaken, Tessa, Fink, Pamela J.

مصطلحات موضوعية: Mice, Animals, Cell Differentiation, Mice, Transgenic, Cell Separation, Thymus Gland, CD8-Positive T-Lymphocytes, Flow Cytometry, Lymphocyte Activation, Adoptive Transfer, Immunologic Memory, Article

الوصف: The youngest peripheral T cells (recent thymic emigrants [RTEs]) are functionally distinct from naive T cells that have completed postthymic maturation. We assessed the RTE memory response and found that RTEs produced less granzyme B than their mature counterparts during infection but proliferated more and, therefore, generated equivalent target killing in vivo. Postinfection, RTE numbers contracted less dramatically than those of mature T cells, but RTEs were delayed in their transition to central memory, displaying impaired expression of CD62L, IL-2, Eomesodermin, and CXCR4, which resulted in impaired bone marrow localization. RTE-derived and mature memory cells expanded equivalently during rechallenge, indicating that the robust proliferative capacity of RTEs was maintained independently of central memory phenotype. Thus, the diminished effector function and delayed central memory differentiation of RTE-derived memory cells are counterbalanced by their increased proliferative capacity, driving the efficacy of the RTE response to that of mature T cells.

الوصول الحر: https://explore.openaire.eu/search/publication?articleId=pmid________::b2fb87f9aa93e82e694933890e36457eTest
https://europepmc.org/articles/PMC4779721Test/