Dysregulated sensing of self nucleic acid is a leading cause of autoimmunity in multifactorial and monogenic diseases. Mutations in Wiskott-Aldrich syndrome protein (WASp), a key regulator of cytoskeletal dynamics in immune cells, cause autoimmune manifestations and increased production of type-I interferons by innate cells. Here we show that complexes of self-DNA and autoantibodies (DNA-IC) contribute to elevated interferon levels via activation of the cGAS-STING pathway of cytosolic sensing. Mechanistically, lack of endosomal F-actin nucleation by WASp causes a delay in endolysosomal maturation and prolongs the transit time of ingested DNA-IC. Stalling in maturation-defective organelles facilitates leakage of DNA-IC into the cytosol, promoting activation of the TBK1-STING pathway. Genetic deletion of STING, STING and cGAS chemical inhibitors abolish interferon production and rescue systemic activation of interferon stimulated genes in vivo. These data unveil the contribution of cytosolic self-nucleic acid sensing in WAS and underscore the importance of WASp-mediated endosomal actin remodelling to prevent innate activation.
Giulia Maria Piperno, Asma Naseem, Giulia Silvestrelli, Roberto Amadio, Nicoletta Caronni, Karla Evelia Cervantes Luevano, Nalan Liv, Judith Klumperman, Andrea Colliva, Hashim Ali, Francesca Graziano, Philippe Benaroch, Hans Haecker, Richard N. Hanna, Federica Benvenuti
Systemic sclerosis (SSc) is a heterogeneous autoimmune disorder that results in skin fibrosis, autoantibody production and internal organ dysfunction. We previously identified four ‘intrinsic’ subsets of SSc based upon skin gene expression that are found across organ systems. Gene expression regulators that underlie the SSc intrinsic subsets, or are associated with clinical covariates, have not been systematically characterized. Here we present a computational framework to calculate the activity scores of gene expression regulators and identify their associations with SSc clinical outcomes. We find regulator activity scores can reproduce the intrinsic molecular subsets with distinct sets of regulators identified for inflammatory, fibroproliferative and normal-like samples. Regulators most highly correlated with modified Rodnan skin score (MRSS) also varied by intrinsic subset. We identify a subgroup of fibroproliferative/inflammatory SSc patients with more severe pathophenotypes. We further identify a subgroup of SSc patients that had higher MRSS and increased likelihood of interstitial lung disease. Using an independent cohort, we show this group was most likely to show forced vital capacity decline over a period of 36 – 54 months. Our results demonstrate an association between the activation of regulators, gene expression subsets and clinical variables that can identify SSc patients with more severe disease.
Yue Wang, Jennifer M. Franks, Monica Yang, Diana M. Toledo, Tammara A. Wood, Monique Hinchcliff, Michael L. Whitfield
Purpose: There is a rapidly evolving portfolio of immune therapeutic modulators, but the relative incidence of immune targets in human gliomas is unknown. In order to prioritize available immune therapeutics, immune profiling across glioma grades was conducted followed by preclinical determinations of therapeutic effect in immune competent mice harboring gliomas. Methods: CD4+ and CD8+ T cells and CD11b+ myeloid cells were isolated from the blood of healthy donors and the blood and tumors of newly diagnosed and recurrent glioma patients and profiled for the expression of immune modulatory targets with an available therapeutic. Preclinical murine models of glioma were used to assess therapeutic efficacy of agents targeting the most frequently expressed immune targets. Immune effector function was analyzed in the setting of glioma induced immune suppression. Results: In glioma patients, the adenosine-CD73-CD39 immune suppressive pathway was most frequently expressed, followed by PD-1. CD73 expression was upregulated on immune cells by 2-hydroxygluterate in IDH1 mutant glioma patients. In multiple murine glioma models, including those that express CD73, adenosine receptor inhibitors demonstrated a modest therapeutic response; however, the addition of other inhibitors of the adenosine pathway did not further enhance this therapeutic effect. Although adenosine receptor inhibitors could recover immunological effector functions in T cells after the engagement of this pathway, immune recovery was impaired in the presence of gliomas, indicating that irreversible immune exhaustion limits the effectiveness of inhibitors of the adenosine pathway in glioma patients. Conclusions: This study illustrates vetting steps that should be considered prior to clinical trial implementation for immunotherapy resistant cancers including testing an agents ability to restore immunological function in the context of intended use.
Martina Ott, Karl-Heinz Tomaszowski, Anantha Marisetty, Ling-Yuan Kong, Jun Wei, Maya Duna, Katia Blumberg, Xiaorong Ji, Carmen B Jacobs, Gregory N. Fuller, Lauren A. Langford, Jason T. Huse, James P. Long, Jian Hu, Shulin Li, Jeffrey S. Weinberg, Sujit Prabhu, Raymond Sawaya, Sherise D. Ferguson, Ganesh Rao, Frederick F. Lang, Michael A. Curran, Amy B. Heimberger
Background: Elevated levels of inflammatory cytokines have been associated with poor outcomes among COVID-19 patients. It is unknown, however, how these levels compare to those observed in critically ill patients with ARDS or sepsis due to other causes. Methods: We used a luminex assay to determine expression of 76 cytokines from plasma of hospitalized COVID-19 patients and banked plasma samples from ARDS and sepsis patients. Our analysis focused on detecting statistical differences in levels of 6 cytokines associated with cytokine storm (IL-1b, IL-1RA, IL-6, IL-8, IL-18, and TNFα) between patients with moderate COVID-19, severe COVID-19, and ARDS or sepsis. Results: 15 hospitalized COVID-19 patients, 9 of whom were critically ill, were compared to critically ill patients with ARDS (n = 12) or sepsis (n = 16). There were no statistically significant differences in baseline levels of IL-1b, IL-1RA, IL-6, IL-8, IL-18, and TNFα between patients with COVID-19 and critically ill controls with ARDS or sepsis. Conclusions: Levels of inflammatory cytokines were not higher in severe COVID-19 patients than in moderate COVID-19 or critically ill patients with ARDS or sepsis in this small cohort. Broad use of immunosuppressive therapies in ARDS has failed in numerous Phase 3 studies; use of these therapies in unselected patients with COVID-19 may be unwarranted. Funding: A.J.R.: Stanford ICU Biobank NHLBI K23 HL125663. C.A.B.: Burroughs Wellcome Fund Investigators in the Pathogenesis of Infectious Diseases #1016687; NIH/NIAID U19AI057229-16 (PI MM Davis); Stanford Maternal Child Health Research Institute; Chan Zuckerberg Biohub.
Jennifer G. Wilson, Laura J. Simpson, Anne-Maud Ferreira, Arjun Rustagi, Jonasel A. Roque, Adijat Asuni, Thanmayi Ranganath, Philip M. Grant, Aruna K. Subramanian, Yael Rosenberg-Hasson, Holden Maecker, Susan Holmes, Joseph E. Levitt, Catherine Blish, Angela J. Rogers
Using the global Hipk2-null mice in various models of kidney disease, we previously demonstrated the central role of homeodomain interacting protein kinase 2 (HIPK2) in the development of renal fibrosis. However, whether the renal tubular epithelial cell (RTEC)-specific HIPK2 function significantly contributed to renal fibrogenesis had not been established. Herein, using RTEC-specific HIPK2 null mice and transgenic mice with RTEC-specific overexpression of the wildtype (WT) or kinase-dead (KD) mutant of HIPK2, we now show that the modulation of tubular HIPK2 expression and activity can profoundly affect renal fibrosis development in vivo. The loss of HIPK2 expression in RTECs resulted in a marked diminution of renal fibrosis in mouse models of unilateral obstruction (UUO) and HIV-associated nephropathy (HIVAN) in Tg26 mice, which was associated with the reduction of Smad3 activation and downstream expression of profibrotic markers. Conversely, the overexpression of WT HIPK2 in RTECs accentuated the extent of renal fibrosis in the setting of UUO, HIVAN, and folic acid nephropathy (FAN) in mice. Importantly, the overexpression of HIPK2 KD mutant or administration of BT173, an allosteric inhibitor of HIPK2-Smad3 interaction, markedly attenuated the renal fibrosis in these mouse models of kidney disease, indicating that HIPK2 requires both the kinase activity and its interaction with Smad3 to promote TGF--mediated renal fibrosis. Together, these results establish an important RTEC-specific role of HIPK2 in kidney fibrosis and further substantiates the inhibition of HIPK2 as a therapeutic approach toward renal fibrosis.
Wenzhen Xiao, Jing E, Li Bao, Ying Fan, Yuanmeng Jin, Andrew Wang, David Bauman, Zhengzhe Li, Ya-Li Zheng, Ruijie Liu, Kyung Lee, John Cijiang He
Orphan nuclear receptor estrogen-related receptor (ERR)γ stimulates bile acid production, however, the role and the regulatory mechanism of ERRγ in cholestatic liver disease are largely unknown. This study identifies that Sirt6 is a deacetylase of ERRγ and suggests a novel mechanism by which Sirt6 activation alleviates cholestatic liver damage and fibrosis through regulating ERRγ. We observed that hepatic expression of Sirt6 is repressed while that of ERRγ is upregulated in murine cholestasis models. Hepatocyte-specific Sirt6 knockout mice were more severely injured following a bile duct ligation (BDL) compared to wild-type mice and adenoviral re-expression of Sirt6 reversed liver damage and fibrosis as demonstrated by biochemical and histological analyses. Mechanistically, Sirt6 deacetylated ERRγ, thereby destabilized ERRγ and inhibited its transcriptional activity. Elimination of hepatic ERRγ using Ad-shERRγ abolished the deleterious effects of Sirt6 deficiency, while ERRγ overexpression aggravated cholestatic liver injury. Administration of a Sirt6 deacetylase activator prevented BDL-induced liver damage and fibrosis. In patients with cholestasis, Sirt6 expression was decreased while total- and acetylated-ERRγ levels were increased, confirming negative regulation of ERRγ by Sirt6. Thus, Sirt6 activation represents a new therapeutic strategy for treating cholestatic liver injury.
Lihua Hao, In Hyuk Bang, Jie Wang, Yuancheng Mao, Jae Do Yang, Soon-Young Na, Jeong Kon Seo, Hueng-Sik Choi, Eun Ju Bae, Byung-Hyun Park
Aromatase inhibitors (AIs) reduce breast cancer recurrence and prolong survival, but up to 30% of patients exhibit recurrence. Using a genome-wide association study of patients entered on MA.27, a phase III randomized trial of anastrozole vs exemestane, we identified a SNP in CUB And Sushi Multiple Domains 1 (CSMD1) associated with breast cancer free interval, with the variant allele associated with fewer distant recurrences. Mechanistically, CSMD1 regulates CYP19 expression in a SNP-, and drug-dependent fashion and this regulation is different among three AIs, anastrozole, exemestane, and letrozole. Overexpression of CSMD1 sensitized AI-resistant cells to anastrozole but not to the other two AIs. The SNP in CSMD1 that was associated with increased CSMD1 and CYP19 expression levels increased anastrozole sensitivity, but not letrozole or exemestane sensitivity. Anastrozole degrades estrogen receptor α (ERα), especially in the presence of estradiol (E2). ER positive breast cancer organoids and AI- or fulvestrant-resistant breast cancer cells were more sensitive to anastrozole plus E2 than to AI alone. Our findings suggest that the CSMD1 SNP might help to predict AI response and anastrozole plus E2 serves as a potential new therapeutic strategy for patients with AI- or fulvestrant-resistant breast cancers.
Junmei Cairns, James N. Ingle, Tanda T. M. Dudenkov, Krishna R. Kalari, Erin E. Carlson, Jie Na, Aman U. Buzdar, Mark E. Robson, Matthew J. Ellis, Paul E. Goss, Lois E. Shepherd, Barbara Goodnature, Matthew P. Goetz, Richard M. Weinshilboum, Hu Li, Mehrab Ghanat Bari, Liewei Wang
Nonalcoholic fatty liver disease (NAFLD) is a common comorbidity among people living with HIV with a more aggressive course than in the general population. In a recent randomized placebo-controlled trial, we demonstrated that the growth hormone-releasing hormone analogue tesamorelin reduced liver fat and prevented fibrosis progression in HIV-associated NAFLD over one year. As such, tesamorelin is the first strategy that has shown to be effective against NAFLD among the HIV population. The current study leveraged paired liver biopsy specimens from this trial to identify hepatic gene pathways that are differentially modulated by tesamorelin versus placebo. Using Gene Set Enrichment Analysis (GSEA), we found that tesamorelin increased hepatic expression of hallmark gene sets involved in oxidative phosphorylation and decreased hepatic expression of gene sets contributing to inflammation, tissue repair, and cell division. Tesamorelin also reciprocally up- and downregulated curated gene sets associated with favorable and poor hepatocellular carcinoma prognosis, respectively. Notably, among tesamorelin-treated participants, these changes in hepatic expression correlated with improved fibrosis-related gene score. Our findings inform our knowledge of the biology of growth hormone action on the liver and provide a mechanistic basis for the observed clinical effects of tesamorelin on the liver.
Lindsay T. Fourman, James M. Billingsley, George Agyapong, Shannan J. Ho Sui, Meghan N. Feldpausch, Julia Purdy, Isabel Zheng, Chelsea S. Pan, Kathleen E. Corey, Martin Torriani, David E. Kleiner, Colleen M. Hadigan, Takara L. Stanley, Raymond T. Chung, Steven K. Grinspoon
Current management of childhood leukemia is tailored based on disease risk determined by clinical features at presentation. Whether properties of the host immune response impact disease risk and outcome is not known. Here we combine mass cytometry, single cell genomics and functional studies to characterize the bone marrow immune environment in children with B-cell acute lymphoblastic leukemia, and acute myelogenous leukemia at presentation. T cells in leukemia marrow demonstrate evidence of chronic immune activation and exhaustion/dysfunction, with attrition of naïve T cells and TCF1+ stem-like memory T cells and accumulation of terminally-differentiated effector T cells. Marrow-infiltrating natural killer cells also exhibit evidence of dysfunction, particularly in myeloid leukemia. Properties of immune cells identified distinct immune phenotype-based clusters correlating with disease risk in acute lymphoblastic leukemia. High-risk immune signatures were associated with expression of stem-like genes on tumor cells. These data provide a comprehensive assessment of the immune landscape of childhood leukemias and identify targets potentially amenable to therapeutic intervention. These studies also suggest that properties of the host response with depletion of naïve T cells and accumulation of terminal-effector T cells may contribute to the biologic basis of disease risk. Properties of immune microenvironment identified here may also impact optimal application of immune therapies, including T cell-redirection approaches in childhood leukemia.
Jithendra Kini Bailur, Samuel S. McCachren, Katherine E. Pendleton, Juan C. Vasquez, Hong S. Lim, Alyssa Duffy, Deon Doxie, Akhilesh Kaushal, Connor J.R. Foster, Deborah DeRyckere, Sharon M. Castellino, Melissa L. Kemp, Peng Qiu, Madhav Dhodapkar, Kavita Dhodapkar
COVID-19-associated morbidity and mortality have been attributed to a pathologic host response. Two divergent hypotheses have been proposed: a hyper-inflammatory ‘cytokine-storm’-mediated injury versus failure of host protective immunity resulting in unrestrained viral dissemination and organ injury. A key explanation for the inability to address this controversy has been the lack of diagnostic tools to evaluate immune function in COVID-19 infections. ELISpot, a highly sensitive, functional immunoassay was employed in 27 COVID-19, 51 septic, 18 critically-ill non-septic (CINS), and 27 healthy controls to evaluate adaptive and innate immune status by quantitating T cell IFN-ɣ and monocyte TFN-α production. Circulating T cell subsets were profoundly reduced in COVID-19 patients. Additionally, stimulated blood mononuclear cells produced less than 40% to 50% of the IFN-ɣ and TNF-α observed in septic and CINS patients, consistent with markedly impaired immune effector cell function. Approximately 25% of COVID-19 patients had increased IL-6 levels greater than 1,000 pg/mL that were not associated with elevations in other canonical pro-inflammatory cytokines. Collectively, these findings support the hypothesis that COVID-19 suppresses host functional adaptive and innate immunity. Importantly, Interleukin-7 administered ex vivo restored T cell IFN-ɣ production in COVID-19 patients. Thus, ELISpot may functionally characterize host immunity in COVID-19 and inform prospective therapies.
Kenneth E. Remy, Monty Mazer, David A. Striker, Ali H. Ellebedy, Andrew H. Walton, Jacqueline Unsinger, Teresa M. Blood, Philip A. Mudd, Daehan J. Yi, Daniel A. Mannion, Dale F. Osborne, R. Scott Martin, Nitin J. Anand, James P. Bosanquet, Jane Blood, Anne M. Drewry, Charles C. Caldwell, Isaiah R. Turnbull, Scott C. Brakenridge, Lyle L. Moldawer, Richard S. Hotchkiss
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