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Science Translational Medicine Jun 2022T cell-derived pro-inflammatory cytokines are a major driver of rheumatoid arthritis (RA) pathogenesis. Although these cytokines have traditionally been attributed to...
T cell-derived pro-inflammatory cytokines are a major driver of rheumatoid arthritis (RA) pathogenesis. Although these cytokines have traditionally been attributed to CD4 T cells, we have found that CD8 T cells are notably abundant in synovium and make more interferon (IFN)-γ and nearly as much tumor necrosis factor (TNF) as their CD4 T cell counterparts. Furthermore, using unbiased high-dimensional single-cell RNA-seq and flow cytometric data, we found that the vast majority of synovial tissue and synovial fluid CD8 T cells belong to an effector CD8 T cell population characterized by high expression of granzyme K (GzmK) and low expression of granzyme B (GzmB) and perforin. Functional experiments demonstrate that these GzmK GzmB CD8 T cells are major cytokine producers with low cytotoxic potential. Using T cell receptor repertoire data, we found that CD8 GzmK GzmB T cells are clonally expanded in synovial tissues and maintain their granzyme expression and overall cell state in blood, suggesting that they are enriched in tissue but also circulate. Using GzmK and GzmB signatures, we found that GzmK-expressing CD8 T cells were also the major CD8 T cell population in the gut, kidney, and coronavirus disease 2019 (COVID-19) bronchoalveolar lavage fluid, suggesting that they form a core population of tissue-associated T cells across diseases and human tissues. We term this population tissue-enriched expressing GzmK or T CD8 cells. Armed to produce cytokines in response to both antigen-dependent and antigen-independent stimuli, CD8 T cells have the potential to drive inflammation.
Topics: CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; COVID-19; Cytokines; Granzymes; Humans
PubMed: 35704599
DOI: 10.1126/scitranslmed.abo0686 -
Immunity Jan 2021Systematic understanding of immune aging on a whole-body scale is currently lacking. We characterized age-associated alterations in immune cells across multiple mouse...
Systematic understanding of immune aging on a whole-body scale is currently lacking. We characterized age-associated alterations in immune cells across multiple mouse organs using single-cell RNA and antigen receptor sequencing and flow cytometry-based validation. We defined organ-specific and common immune alterations and identified a subpopulation of age-associated granzyme K (GZMK)-expressing CD8 T (Taa) cells that are distinct from T effector memory (Tem) cells. Taa cells were highly clonal, had specific epigenetic and transcriptional signatures, developed in response to an aged host environment, and expressed markers of exhaustion and tissue homing. Activated Taa cells were the primary source of GZMK, which enhanced inflammatory functions of non-immune cells. In humans, proportions of the circulating GZMKCD8 T cell population that shares transcriptional and epigenetic signatures with mouse Taa cells increased during healthy aging. These results identify GZMK Taa cells as a potential target to address age-associated dysfunctions of the immune system.
Topics: Aging; Animals; CD8-Positive T-Lymphocytes; Cells, Cultured; Clone Cells; Cytotoxicity, Immunologic; Female; Gene Expression Profiling; Granzymes; Humans; Immune System; Immunologic Memory; Inflammation; Mice; Mice, Inbred C57BL; Receptors, Antigen, B-Cell; Receptors, Antigen, T-Cell; Sequence Analysis, RNA; Single-Cell Analysis; Transcriptome
PubMed: 33271118
DOI: 10.1016/j.immuni.2020.11.005 -
Granzyme B and perforin are important for regulatory T cell-mediated suppression of tumor clearance.Immunity Oct 2007Granzyme B is important for the ability of NK cells and CD8(+) T cells to kill their targets. However, we showed here that granzyme B-deficient mice clear both...
Granzyme B is important for the ability of NK cells and CD8(+) T cells to kill their targets. However, we showed here that granzyme B-deficient mice clear both allogeneic and syngeneic tumor cell lines more efficiently than do wild-type (WT) mice. To determine whether regulatory T (Treg) cells utilize granzyme B to suppress immune responses against these tumors, we examined the expression and function of granzyme B in Treg cells. Granzyme B was not expressed in naive Treg cells but was highly expressed in 5%-30% of CD4(+)Foxp3(+) Treg cells in the tumor environment. Adoptive transfer of WT Treg cells, but not granzyme B- or perforin-deficient Treg cells, into granzyme B-deficient mice partially restored susceptibility to tumor growth; Treg cells derived from the tumor environment could induce NK and CD8(+) T cell death in a granzyme B- and perforin-dependent fashion. Granzyme B and perforin are therefore relevant for Treg cell-mediated suppression of tumor clearance in vivo.
Topics: Adoptive Transfer; Animals; CD8-Positive T-Lymphocytes; Cell Line, Tumor; Cytotoxicity, Immunologic; Flow Cytometry; Granzymes; Killer Cells, Natural; Lymphocyte Subsets; Lymphocytes, Tumor-Infiltrating; Mice; Mice, Congenic; Models, Immunological; Neoplasms, Experimental; Perforin; T-Lymphocytes, Regulatory
PubMed: 17919943
DOI: 10.1016/j.immuni.2007.08.014 -
Nature Communications Mar 2021Acute myocardial infarction is a common condition responsible for heart failure and sudden death. Here, we show that following acute myocardial infarction in mice, CD8 T...
Acute myocardial infarction is a common condition responsible for heart failure and sudden death. Here, we show that following acute myocardial infarction in mice, CD8 T lymphocytes are recruited and activated in the ischemic heart tissue and release Granzyme B, leading to cardiomyocyte apoptosis, adverse ventricular remodeling and deterioration of myocardial function. Depletion of CD8 T lymphocytes decreases apoptosis within the ischemic myocardium, hampers inflammatory response, limits myocardial injury and improves heart function. These effects are recapitulated in mice with Granzyme B-deficient CD8 T cells. The protective effect of CD8 depletion on heart function is confirmed by using a model of ischemia/reperfusion in pigs. Finally, we reveal that elevated circulating levels of GRANZYME B in patients with acute myocardial infarction predict increased risk of death at 1-year follow-up. Our work unravels a deleterious role of CD8 T lymphocytes following acute ischemia, and suggests potential therapeutic strategies targeting pathogenic CD8 T lymphocytes in the setting of acute myocardial infarction.
Topics: Animals; Apoptosis; CD8-Positive T-Lymphocytes; Disease Models, Animal; Female; Granzymes; Heart; Heart Failure; Homeodomain Proteins; Humans; Male; Mice; Mice, Inbred C57BL; Mice, Knockout; Myocardial Infarction; Myocardium; Swine; Transcriptome; Ventricular Remodeling
PubMed: 33674611
DOI: 10.1038/s41467-021-21737-9 -
The Journal of Clinical Investigation Aug 2022Accurately identifying patients who respond to immunotherapy remains clinically challenging. A noninvasive method that can longitudinally capture information about...
Accurately identifying patients who respond to immunotherapy remains clinically challenging. A noninvasive method that can longitudinally capture information about immune cell function and assist in the early assessment of tumor responses is highly desirable for precision immunotherapy. Here, we show that PET imaging using a granzyme B-targeted radiotracer named 68Ga-grazytracer, could noninvasively and effectively predict tumor responses to immune checkpoint inhibitors and adoptive T cell transfer therapy in multiple tumor models. 68Ga-grazytracer was designed and selected from several radiotracers based on non-aldehyde peptidomimetics, and exhibited excellent in vivo metabolic stability and favorable targeting efficiency to granzyme B secreted by effector CD8+ T cells during immune responses. 68Ga-grazytracer permitted more sensitive discrimination of responders and nonresponders than did 18F-fluorodeoxyglucose, distinguishing between tumor pseudoprogression and true progression upon immune checkpoint blockade therapy in mouse models with varying immunogenicity. In a preliminary clinical trial with 5 patients, no adverse events were observed after 68Ga-grazytracer injection, and clinical responses in cancer patients undergoing immunotherapy were favorably correlated with 68Ga-grazytracer PET results. These results highlight the potential of 68Ga-grazytracer PET to enhance the clinical effectiveness of granzyme B secretion-related immunotherapies by supporting early response assessment and precise patient stratification in a noninvasive and longitudinal manner.
Topics: Animals; CD8-Positive T-Lymphocytes; Granzymes; Immunologic Factors; Immunotherapy; Mice; Neoplasms; Positron-Emission Tomography
PubMed: 35788116
DOI: 10.1172/JCI161065 -
The Journal of Experimental Medicine Sep 2019NK cells eliminate virus-infected and tumor cells by releasing cytotoxic granules containing granzyme B (GrzB) or by engaging death receptors that initiate caspase...
NK cells eliminate virus-infected and tumor cells by releasing cytotoxic granules containing granzyme B (GrzB) or by engaging death receptors that initiate caspase cascades. The orchestrated interplay between both cell death pathways remains poorly defined. Here we simultaneously measure the activities of GrzB and caspase-8 in tumor cells upon contact with human NK cells. We observed that NK cells switch from inducing a fast GrzB-mediated cell death in their first killing events to a slow death receptor-mediated killing during subsequent tumor cell encounters. Target cell contact reduced intracellular GrzB and perforin and increased surface-CD95L in NK cells over time, showing how the switch in cytotoxicity pathways is controlled. Without perforin, NK cells were unable to perform GrzB-mediated serial killing and only killed once via death receptors. In contrast, the absence of CD95 on tumor targets did not impair GrzB-mediated serial killing. This demonstrates that GrzB and death receptor-mediated cytotoxicity are differentially regulated during NK cell serial killing.
Topics: Caspase 8; Cytotoxicity, Immunologic; Granzymes; HeLa Cells; Humans; Killer Cells, Natural; Kinetics; Perforin; Receptors, Death Domain; fas Receptor
PubMed: 31270246
DOI: 10.1084/jem.20181454 -
International Journal of Molecular... Aug 2023Natural killer (NK) cells are cytotoxic lymphocytes that are critical for the innate immune system. Engineering NK cells with chimeric antigen receptors (CARs) allows...
Natural killer (NK) cells are cytotoxic lymphocytes that are critical for the innate immune system. Engineering NK cells with chimeric antigen receptors (CARs) allows CAR-NK cells to target tumor antigens more effectively. In this report, we present novel CAR mRNA-LNP (lipid nanoparticle) technology to effectively transfect NK cells expanded from primary PBMCs and to generate functional CAR-NK cells. CD19-CAR mRNA and BCMA-CAR mRNA were embedded into LNPs that resulted in 78% and 95% CAR expression in NK cells, respectively. BCMA-CAR-NK cells after transfection with CAR mRNA-LNPs killed multiple myeloma RPMI8226 and MM1S cells and secreted IFN-gamma and Granzyme B in a dose-dependent manner in vitro. In addition, CD19-CAR-NK cells generated with CAR mRNA-LNPs killed Daudi and Nalm-6 cells and secreted IFN-gamma and Granzyme B in a dose-dependent manner. Both BCMA-CAR-NK and CD19-CAR-NK cells showed significantly higher cytotoxicity, IFN-gamma, and Granzyme B secretion compared with normal NK cells. Moreover, CD19-CAR-NK cells significantly blocked Nalm-6 tumor growth in vivo. Thus, non-viral delivery of CAR mRNA-LNPs can be used to generate functional CAR-NK cells with high anti-tumor activity.
Topics: Humans; Receptors, Chimeric Antigen; Granzymes; B-Cell Maturation Antigen; Killer Cells, Natural; Multiple Myeloma; Adaptor Proteins, Signal Transducing; Antigens, CD19
PubMed: 37686170
DOI: 10.3390/ijms241713364 -
Science Immunology Apr 2022Innate lymphocytes are integral components of the cellular immune system that can coordinate host defense against a multitude of challenges and trigger immunopathology...
Innate lymphocytes are integral components of the cellular immune system that can coordinate host defense against a multitude of challenges and trigger immunopathology when dysregulated. Natural killer (NK) cells and innate lymphoid cells (ILCs) are innate immune effectors postulated to functionally mirror conventional cytotoxic T lymphocytes and helper T cells, respectively. Here, we showed that the cytolytic molecule granzyme C was expressed in cells with the phenotype of type 1 ILCs (ILC1s) in mouse liver and salivary gland. Cell fate-mapping and transfer studies revealed that granzyme C-expressing innate lymphocytes could be derived from ILC progenitors and did not interconvert with NK cells, ILC2s, or ILC3s. Granzyme C defined a maturation state of ILC1s. These granzyme C-expressing ILC1s required the transcription factors T-bet and, to a lesser extent, Eomes and support from transforming growth factor-β (TGF-β) signaling for their maintenance in the salivary gland. In a transgenic mouse breast cancer model, depleting ILC1s caused accelerated tumor growth. ILC1s gained granzyme C expression following interleukin-15 (IL-15) stimulation, which enabled perforin-mediated cytotoxicity. Constitutive activation of STAT5, a transcription factor regulated by IL-15, in granzyme C-expressing ILC1s triggered lethal perforin-dependent autoimmunity in neonatal mice. Thus, granzyme C marks a cytotoxic effector state of ILC1s, broadening their function beyond "helper-like" lymphocytes.
Topics: Animals; Autoimmunity; Granzymes; Immunity, Innate; Interleukin-15; Killer Cells, Natural; Mice; Perforin
PubMed: 35394814
DOI: 10.1126/sciimmunol.abi8642 -
International Journal of Molecular... Feb 2022Cytotoxic T lymphocytes, differentiated CD8+ T cells, use multiple mechanisms to mediate their function, including release of granules containing perforin and granzymes... (Review)
Review
Cytotoxic T lymphocytes, differentiated CD8+ T cells, use multiple mechanisms to mediate their function, including release of granules containing perforin and granzymes at target cells. Granzymes are a family of cytotoxic proteases that each act on unique sets of biological substrates within target cells, usually to induce cell death. Granzymes are differentially expressed within T cells, depending on their environment and activation state, making the granzyme cytotoxic pathway dynamic and responsive to individual circumstances. In this review, we describe what is currently known about granzyme structure, processing, and granzyme-induced cell death in the context of cancer and in some other inflammatory diseases.
Topics: Animals; CD8-Positive T-Lymphocytes; Gene Expression Regulation; Granzymes; Humans; T-Lymphocytes, Cytotoxic
PubMed: 35163755
DOI: 10.3390/ijms23031833 -
American Journal of Physiology. Cell... Jul 2022The predominant function of the skin is to serve as a barrier-to protect against external insults and to prevent water loss. Junctional and structural proteins in the... (Review)
Review
The predominant function of the skin is to serve as a barrier-to protect against external insults and to prevent water loss. Junctional and structural proteins in the stratum corneum, the outermost layer of the epidermis, are critical to the integrity of the epidermal barrier as it balances ongoing outward migration, differentiation, and desquamation of keratinocytes in the epidermis. As such, epidermal barrier function is highly susceptible to upsurges of proteolytic activity in the stratum corneum and epidermis. Granzyme B is a serine protease scarce in healthy tissues but present at high levels in tissues encumbered by chronic inflammation. Discovered in the 1980s, granzyme B is currently recognized for its intracellular roles in immune cell-mediated apoptosis as well as extracellular roles in inflammation, chronic injuries, tissue remodeling, as well as processing of cytokines, matrix proteins, and autoantigens. Increasing evidence has emerged in recent years supporting a role for granzyme B in promoting barrier dysfunction in the epidermis by direct cleavage of barrier proteins and eliciting immunoreactivity. Likewise, granzyme B contributes to impaired epithelial function of the airways, retina, gut, and vessels. In the present review, the role of granzyme B in cutaneous epithelial dysfunction is discussed in the context of specific conditions with an overview of underlying mechanisms as well as utility of current experimental and therapeutic inhibitors.
Topics: Epidermis; Granzymes; Humans; Inflammation; Keratinocytes; Skin Diseases
PubMed: 35442832
DOI: 10.1152/ajpcell.00052.2022