Browsing by Author "Savadkar, Shivraj"

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    Dectin 1 activation on macrophages by galectin 9 promotes pancreatic carcinoma and peritumoral immune tolerance.
    (Nature medicine, 2017-05) Daley, Donnele; Mani, Vishnu R; Mohan, Navyatha; Akkad, Neha; Ochi, Atsuo; Heindel, Daniel W; Lee, Ki Buom; Zambirinis, Constantinos P; Pandian, Gautam Sd Balasubramania; Savadkar, Shivraj; Torres-Hernandez, Alejandro; Nayak, Shruti; Wang, Ding; Hundeyin, Mautin; Diskin, Brian; Aykut, Berk; Werba, Gregor; Barilla, Rocky M; Rodriguez, Robert; Chang, Steven; Gardner, Lawrence; Mahal, Lara K; Ueberheide, Beatrix; Miller, George
    The progression of pancreatic oncogenesis requires immune-suppressive inflammation in cooperation with oncogenic mutations. However, the drivers of intratumoral immune tolerance are uncertain. Dectin 1 is an innate immune receptor crucial for anti-fungal immunity, but its role in sterile inflammation and oncogenesis has not been well defined. Furthermore, non-pathogen-derived ligands for dectin 1 have not been characterized. We found that dectin 1 is highly expressed on macrophages in pancreatic ductal adenocarcinoma (PDA). Dectin 1 ligation accelerated the progression of PDA in mice, whereas deletion of Clec7a-the gene encoding dectin 1-or blockade of dectin 1 downstream signaling was protective. We found that dectin 1 can ligate the lectin galectin 9 in mouse and human PDA, which results in tolerogenic macrophage programming and adaptive immune suppression. Upon disruption of the dectin 1-galectin 9 axis, CD4+ and CD8+ T cells, which are dispensable for PDA progression in hosts with an intact signaling axis, become reprogrammed into indispensable mediators of anti-tumor immunity. These data suggest that targeting dectin 1 signaling is an attractive strategy for developing an immunotherapy for PDA.
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    Innate αβ T Cells Mediate Antitumor Immunity by Orchestrating Immunogenic Macrophage Programming
    (Cancer Discovery, 2019-09-01) Hundeyin, Mautin; Kurz, Emma; Mishra, Ankita; Rossi, Juan Andres Kochen; Liudahl, Shannon M; Leis, Kenna R; Mehrotra, Harshita; Kim, Mirhee; Torres, Luisana E; Ogunsakin, Adesola; Link, Jason; Sears, Rosalie C; Sivagnanam, Shamilene; Goecks, Jeremy; Islam, KM Sadeq; Dolgalev, Igor; Savadkar, Shivraj; Wang, Wei; Aykut, Berk; Leinwand, Joshua; Diskin, Brian; Adam, Salma; Israr, Muhammad; Gelas, Maeliss; Lish, Justin; Chin, Kathryn; Farooq, Mohammad Saad; Wadowski, Benjamin; Wu, Jingjing; Shah, Suhagi; Adeegbe, Dennis O; Pushalkar, Smruti; Vasudevaraja, Varshini; Saxena, Deepak; Wong, Kwok-Kin; Coussens, Lisa M; Miller, George
    Abstract Unconventional T-lymphocyte populations are emerging as important regulators of tumor immunity. Despite this, the role of TCRαβ+CD4−CD8−NK1.1− innate αβ T cells (iαβT) in pancreatic ductal adenocarcinoma (PDA) has not been explored. We found that iαβTs represent ∼10% of T lymphocytes infiltrating PDA in mice and humans. Intratumoral iαβTs express a distinct T-cell receptor repertoire and profoundly immunogenic phenotype compared with their peripheral counterparts and conventional lymphocytes. iαβTs comprised ∼75% of the total intratumoral IL17+ cells. Moreover, iαβT-cell adoptive transfer is protective in both murine models of PDA and human organotypic systems. We show that iαβT cells induce a CCR5-dependent immunogenic macrophage reprogramming, thereby enabling marked CD4+ and CD8+ T-cell expansion/activation and tumor protection. Collectively, iαβTs govern fundamental intratumoral cross-talk between innate and adaptive immune populations and are attractive therapeutic targets. Significance: We found that iαβTs are a profoundly activated T-cell subset in PDA that slow tumor growth in murine and human models of disease. iαβTs induce a CCR5-dependent immunogenic tumor-associated macrophage program, T-cell activation and expansion, and should be considered as novel targets for immunotherapy. See related commentary by Banerjee et al., p. 1164. This article is highlighted in the In This Issue feature, p. 1143
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    NLRP3 signaling drives macrophage-induced adaptive immune suppression in pancreatic carcinoma.
    (The Journal of experimental medicine, 2017-06) Daley, Donnele; Mani, Vishnu R; Mohan, Navyatha; Akkad, Neha; Pandian, Gautam SD Balasubramania; Savadkar, Shivraj; Lee, Ki Buom; Torres-Hernandez, Alejandro; Aykut, Berk; Diskin, Brian; Wang, Wei; Farooq, Mohammad S; Mahmud, Arif I; Werba, Gregor; Morales, Eduardo J; Lall, Sarah; Wadowski, Benjamin J; Rubin, Amanda G; Berman, Matthew E; Narayanan, Rajkishen; Hundeyin, Mautin; Miller, George
    The tumor microenvironment (TME) in pancreatic ductal adenocarcinoma (PDA) is characterized by immune tolerance, which enables disease to progress unabated by adaptive immunity. However, the drivers of this tolerogenic program are incompletely defined. In this study, we found that NLRP3 promotes expansion of immune-suppressive macrophages in PDA. NLRP3 signaling in macrophages drives the differentiation of CD4+ T cells into tumor-promoting T helper type 2 cell (Th2 cell), Th17 cell, and regulatory T cell populations while suppressing Th1 cell polarization and cytotoxic CD8+ T cell activation. The suppressive effects of NLRP3 signaling were IL-10 dependent. Pharmacological inhibition or deletion of NLRP3, ASC (apoptosis-associated speck-like protein containing a CARD complex), or caspase-1 protected against PDA and was associated with immunogenic reprogramming of innate and adaptive immunity within the TME. Similarly, transfer of PDA-entrained macrophages or T cells from NLRP3-/- hosts was protective. These data suggest that targeting NLRP3 holds the promise for the immunotherapy of PDA.
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    RIP1 Kinase Drives Macrophage-Mediated Adaptive Immune Tolerance in Pancreatic Cancer
    (Cancer Cell, 2018-11) Wang, Wei; Marinis, Jill M; Beal, Allison M; Savadkar, Shivraj; Wu, Yue; Khan, Mohammed; Taunk, Pardeep S; Wu, Nan; Su, Wenyu; Wu, Jingjing; Ahsan, Aarif; Kurz, Emma; Chen, Ting; Yaboh, Inedouye; Li, Fei; Gutierrez, Johana; Diskin, Brian; Hundeyin, Mautin; Reilly, Michael; Lich, John D; Harris, Philip A; Mahajan, Mukesh K; Thorpe, James H; Nassau, Pamela; Mosley, Julie E; Leinwand, Joshua; Kochen Rossi, Juan A; Mishra, Ankita; Aykut, Berk; Glacken, Michael; Ochi, Atsuo; Verma, Narendra; Kim, Jacqueline I; Vasudevaraja, Varshini; Adeegbe, Dennis; Almonte, Christina; Bagdatlioglu, Ece; Cohen, Deirdre J; Wong, Kwok-Kin; Bertin, John; Miller, George
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    The Pancreatic Cancer Microbiome Promotes Oncogenesis by Induction of Innate and Adaptive Immune Suppression
    (Cancer Discovery, 2018-04-01) Pushalkar, Smruti; Hundeyin, Mautin; Daley, Donnele; Zambirinis, Constantinos P; Kurz, Emma; Mishra, Ankita; Mohan, Navyatha; Aykut, Berk; Usyk, Mykhaylo; Torres, Luisana E; Werba, Gregor; Zhang, Kevin; Guo, Yuqi; Li, Qianhao; Akkad, Neha; Lall, Sarah; Wadowski, Benjamin; Gutierrez, Johana; Kochen Rossi, Juan Andres; Herzog, Jeremy W; Diskin, Brian; Torres-Hernandez, Alejandro; Leinwand, Josh; Wang, Wei; Taunk, Pardeep S; Savadkar, Shivraj; Janal, Malvin; Saxena, Anjana; Li, Xin; Cohen, Deirdre; Sartor, R Balfour; Saxena, Deepak; Miller, George
    Abstract We found that the cancerous pancreas harbors a markedly more abundant microbiome compared with normal pancreas in both mice and humans, and select bacteria are differentially increased in the tumorous pancreas compared with gut. Ablation of the microbiome protects against preinvasive and invasive pancreatic ductal adenocarcinoma (PDA), whereas transfer of bacteria from PDA-bearing hosts, but not controls, reverses tumor protection. Bacterial ablation was associated with immunogenic reprogramming of the PDA tumor microenvironment, including a reduction in myeloid-derived suppressor cells and an increase in M1 macrophage differentiation, promoting TH1 differentiation of CD4+ T cells and CD8+ T-cell activation. Bacterial ablation also enabled efficacy for checkpoint-targeted immunotherapy by upregulating PD-1 expression. Mechanistically, the PDA microbiome generated a tolerogenic immune program by differentially activating select Toll-like receptors in monocytic cells. These data suggest that endogenous microbiota promote the crippling immune-suppression characteristic of PDA and that the microbiome has potential as a therapeutic target in the modulation of disease progression. Significance: We found that a distinct and abundant microbiome drives suppressive monocytic cellular differentiation in pancreatic cancer via selective Toll-like receptor ligation leading to T-cell anergy. Targeting the microbiome protects against oncogenesis, reverses intratumoral immune tolerance, and enables efficacy for checkpoint-based immunotherapy. These data have implications for understanding immune suppression in pancreatic cancer and its reversal in the clinic. Cancer Discov; 8(4); 403–16. ©2018 AACR. See related commentary by Riquelme et al., p. 386. This article is highlighted in the In This Issue feature, p. 371