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40 result(s) for "Sunwoo, John B"
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Identification of cell types in multiplexed in situ images by combining protein expression and spatial information using CELESTA
Advances in multiplexed in situ imaging are revealing important insights in spatial biology. However, cell type identification remains a major challenge in imaging analysis, with most existing methods involving substantial manual assessment and subjective decisions for thousands of cells. We developed an unsupervised machine learning algorithm, CELESTA, which identifies the cell type of each cell, individually, using the cell’s marker expression profile and, when needed, its spatial information. We demonstrate the performance of CELESTA on multiplexed immunofluorescence images of colorectal cancer and head and neck squamous cell carcinoma (HNSCC). Using the cell types identified by CELESTA, we identify tissue architecture associated with lymph node metastasis in HNSCC, and validate our findings in an independent cohort. By coupling our spatial analysis with single-cell RNA-sequencing data on proximal sections of the same specimens, we identify cell–cell crosstalk associated with lymph node metastasis, demonstrating the power of CELESTA to facilitate identification of clinically relevant interactions. CELESTA identifies cell types in multiplexed imaging datasets based on the expression profiles of cells and their spatial information.
Emerging NK cell therapies for cancer and the promise of next generation engineering of iPSC-derived NK cells
Adoptive cell therapy is a rapidly advancing approach to cancer immunotherapy that seeks to facilitate antitumor responses by introducing potent effector cells into the tumor microenvironment. Expanded autologous T cells, particularly T cells with engineered T cell receptors (TCR) and chimeric antigen receptor-T cells have had success in various hematologic malignancies but have faced challenges when applied to solid tumors. As a result, other immune subpopulations may provide valuable and orthogonal options for treatment. Natural killer (NK) cells offer the possibility of significant tumor clearance and recruitment of additional immune subpopulations without the need for prior antigen presentation like in T or B cells that could require removal of endogenous antigen specificity mediated via the T cell receptor (TCR and/or the B ecll receptor (BCR). In recent years, NK cells have been demonstrated to be increasingly important players in the immune response against cancer. Here, we review multiple avenues for allogeneic NK cell therapy, including derivation of NK cells from peripheral blood or umbilical cord blood, the NK-92 immortalized cell line, and induced pluripotent stem cells (iPSCs). We also describe the potential of engineering iPSC-derived NK cells and the utility of this platform. Finally, we consider the benefits and drawbacks of each approach and discuss recent developments in the manufacturing and genetic or metabolic engineering of NK cells to have robust and prolonged antitumor responses in preclinical and clinical settings.
Landscape of innate lymphoid cells in human head and neck cancer reveals divergent NK cell states in the tumor microenvironment
Natural killer (NK) cells comprise one subset of the innate lymphoid cell (ILC) family. Despite reported antitumor functions of NK cells, their tangible contribution to tumor control in humans remains controversial. This is due to incomplete understanding of the NK cell states within the tumor microenvironment (TME). Here, we demonstrate that peripheral circulating NK cells differentiate down two divergent pathways within the TME, resulting in different end states. One resembles intraepithelial ILC1s (ieILC1) and possesses potent in vivo antitumor activity. The other expresses genes associated with immune hyporesponsiveness and has poor antitumor functional capacity. Interleukin-15 (IL-15) and direct contact between the tumor cells and NK cells are required for the differentiation into CD49a⁺CD103⁺ cells, resembling ieILC1s. These data explain the similarity between ieILC1s and tissue-resident NK cells, provide insight into the origin of ieILC1s, and identify the ieILC1-like cell state within the TME to be the NK cell phenotype with the greatest antitumor activity. Because the proportions of the different ILC states vary between tumors, these findings provide a resource for the clinical study of innate immune responses against tumors and the design of novel therapy.
NSD1 inactivation defines an immune cold, DNA hypomethylated subtype in squamous cell carcinoma
Chromatin modifying enzymes are frequently mutated in cancer, resulting in widespread epigenetic deregulation. Recent reports indicate that inactivating mutations in the histone methyltransferase NSD1 define an intrinsic subtype of head and neck squamous cell carcinoma (HNSC) that features pronounced DNA hypomethylation. Here, we describe a similar hypomethylated subtype of lung squamous cell carcinoma (LUSC) that is enriched for both inactivating mutations and deletions in NSD1 . The ‘NSD1 subtypes’ of HNSC and LUSC are highly correlated at the DNA methylation and gene expression levels, featuring ectopic expression of developmental transcription factors and genes that are also hypomethylated in Sotos syndrome, a congenital disorder caused by germline NSD1 mutations. Further, the NSD1 subtype of HNSC displays an ‘immune cold’ phenotype characterized by low infiltration of tumor-associated leukocytes, particularly macrophages and CD8 + T cells, as well as low expression of genes encoding the immunotherapy target PD-1 immune checkpoint receptor and its ligands. Using an in vivo model, we demonstrate that NSD1 inactivation results in reduced T cell infiltration into the tumor microenvironment, implicating NSD1 as a tumor cell-intrinsic driver of an immune cold phenotype. NSD1 inactivation therefore causes epigenetic deregulation across cancer sites, and has implications for immunotherapy.
Modulation of natural killer cell antitumor activity by the aryl hydrocarbon receptor
The aryl hydrocarbon receptor (AhR) has become increasingly recognized for its role in the differentiation and activity of immune cell subsets; however, its role in regulating the activity of natural killer (NK) cells has not been described. Here, we show that AhR expression is induced in murine NK cells upon cytokine stimulation. We show that in the absence of AhR, NK cells have reduced cytolytic activity and reduced capacity to control RMA-S tumor formation in vivo, despite having normal development and maturation markers. Although AhR was first identified to bind the xenobiotic compound dioxin, AhR is now known to bind a variety of natural exogenous (e.g., dietary) and endogenous ligands. We show that activation of AhR with an endogenous tryptophan derivative, 6-formylindolo[3,2- b ]carbazole, potentiates NK cell IFN-γ production and cytolytic activity. Further, administration of 6-formylindolo[3,2- b ]carbazole in vivo enhances NK cell control of tumors in an NK cell- and AhR-dependent manner. Finally, similar effects on NK cell potency occur with AhR dietary ligands, potentially explaining the numerous associations that have been observed in the past between diet and NK cell function. Our studies introduce AhR as another regulator of NK cell activity in vivo.
High-resolution positron emission microscopy of patient-derived tumor organoids
Tumor organoids offer new opportunities for translational cancer research, but unlike animal models, their broader use is hindered by the lack of clinically relevant imaging endpoints. Here, we present a positron-emission microscopy method for imaging clinical radiotracers in patient-derived tumor organoids with spatial resolution 100-fold better than clinical positron emission tomography (PET). Using this method, we quantify 18 F-fluorodeoxyglucose influx to show that patient-derived tumor organoids recapitulate the glycolytic activity of the tumor of origin, and thus, could be used to predict therapeutic response in vitro. Similarly, we measure sodium-iodine symporter activity using 99m Tc- pertechnetate and find that the iodine uptake pathway is functionally conserved in organoids derived from thyroid carcinomas. In conclusion, organoids can be imaged using clinical radiotracers, which opens new possibilities for identifying promising drug candidates and radiotracers, personalizing treatment regimens, and incorporating clinical imaging biomarkers in organoid-based co-clinical trials. Positron emission tomography (PET) radiotracers measure the metabolic activity in cancer cells in patients. Here, the authors develop a microscopy method to image organoids using clinical radiotracers, which allows a direct comparison to PET imaging in patients.
Licensing of natural killer cells by host major histocompatibility complex class I molecules
Self versus non-self discrimination is a central theme in biology from plants 1 to vertebrates, and is particularly relevant for lymphocytes that express receptors capable of recognizing self-tissues and foreign invaders. Comprising the third largest lymphocyte population, natural killer (NK) cells recognize and kill cellular targets and produce pro-inflammatory cytokines. These potentially self-destructive effector functions can be controlled by inhibitory receptors for the polymorphic major histocompatibility complex (MHC) class I molecules that are ubiquitously expressed on target cells 2 , 3 , 4 . However, inhibitory receptors are not uniformly expressed on NK cells, and are germline-encoded by a set of polymorphic genes that segregate independently from MHC genes 5 , 6 . Therefore, how NK-cell self-tolerance arises in vivo is poorly understood. Here we demonstrate that NK cells acquire functional competence through ‘licensing’ by self-MHC molecules. Licensing involves a positive role for MHC-specific inhibitory receptors and requires the cytoplasmic inhibitory motif originally identified in effector responses. This process results in two types of self-tolerant NK cells—licensed or unlicensed—and may provide new insights for exploiting NK cells in immunotherapy. This self-tolerance mechanism may be more broadly applicable within the vertebrate immune system because related germline-encoded inhibitory receptors are widely expressed on other immune cells.
Patterns of Influenza Vaccination in Head and Neck Cancer Patients in the United States
The American Society of Clinical Oncology recommends routine influenza vaccination for cancer patients. Lack of influenza vaccination may lead to increased infection incidence, increased infection severity, and delays in cancer care. Vaccine uptake among head and neck patients is unknown. We performed a retrospective cohort analysis using the SEER-Medicare database for patients above age 65 with head and neck cancer diagnosed between 2013 and 2018. Among 32,155 patients, 32.5% received vaccination in the year before diagnosis and 32.1% in the year after diagnosis. Analyses revealed a significant increase in vaccination at the time of diagnosis and fewer vaccinations in the 3 months afterward. Various factors were associated with decreased odds of receiving vaccination, including Black and AAPI race/ethnicity, male gender, and regional and distant metastasis. Vaccination uptake is suboptimal in patients with head and neck cancer, underscoring the need for targeted interventions to enhance preventive care to improve outcomes in high-risk patients.
An intraepithelial ILC1-like natural killer cell subset produces IL-13
Natural killer (NK) cells are innate immune effectors with considerable heterogeneity and potent antitumor capabilities. Intraepithelial ILC1 (ieILC1)-like NK cells, a population of cytotoxic tissue-resident innate lymphoid cells, have recently been documented in the microenvironment of head and neck squamous cell carcinomas (HNSCC) and other solid tumors. These cells have antitumor cytolytic potential and are potent producers of type 1 cytokines, including IFNγ. Here, we identify a subpopulation of ex vivo differentiated ieILC1-like NK cells that produce IL-13 upon stimulation. Functional characterization revealed that these cells co-expressed IFNγ and IL-13 while maintaining an ILC1 transcriptional signature. IL-13 was induced either upon co-culture with tumor cell lines, or in response to TGF-β and IL-15. IL-13-expressing ieILC1-like NK cells were identified among tumor infiltrating lymphocytes expanded from patient HNSCC tumors, in support of their in vivo existence in primary tumors. These data demonstrate additional heterogeneity within the ieILC1-like NK cell population than previously appreciated and highlight a unique form of ILC plasticity in which cells with clear ILC1 transcriptional profiles express a type 2 cytokine. With the known roles of IL-13 in cancer cell growth dynamics and immunoregulation, the identification of this subset within tumor microenvironments presents a potential target for therapeutic manipulation.
AHR Regulates NK Cell Migration via ASB2–Mediated Ubiquitination of Filamin A
Natural killer (NK) cells are effector cells of the innate immune system involved in defense against virus-infected and transformed cells. The effector function of NK cells is linked to their ability to migrate to sites of inflammation or damage. Therefore, understanding the factors regulating NK cell migration is of substantial interest. Here, we show that in the absence of aryl hydrocarbon receptor (AHR), a ligand-activated transcription factor, NK cells have reduced capacity to migrate and infiltrate tumors in vivo . Analysis of differentially expressed genes revealed that ankyrin repeat and SOCS Box containing 2 ( Asb2 ) expression was dramatically decreased in Ahr –/– NK cells and that AhR ligands modulated its expression. Further, AhR directly regulated the promoter region of the Asb2 gene. Similar to what was observed with murine Ahr –/– NK cells, ASB2 knockdown inhibited the migration of human NK cells. Activation of AHR by its agonist FICZ induced ASB2-dependent filamin A degradation in NK cells; conversely, knockdown of endogenous ASB2 inhibited filamin A degradation. Reduction of filamin A increased the migration of primary NK cells and restored the invasion capacity of AHR-deficient NK cells. Our study introduces AHR as a new regulator of NK cell migration, through an AHR-ASB2-filamin A axis and provides insight into a potential therapeutic target for NK cell-based immunotherapies.