Research
Abstract
Rest has long been considered beneficial to patient healing, yet remarkably there are no evidence-based experimental models determining how it benefits disease outcomes. Here, we create a novel experimental rest model in mice that briefly extends the morning rest period. We found, in two different major cardiovascular disease conditions (cardiac hypertrophy, myocardial infarction), that imposing a short, extended period of morning rest each day limits cardiac remodeling, as compared to controls. Mechanistically, rest mitigates autonomic-mediated hemodynamic stress on the cardiovascular system, relaxes myofilament contractility, attenuates cardiac remodeling genes, consistent with the benefits on cardiac structure and function. These same rest-responsive gene pathways underlie the pathophysiology of many major human cardiovascular conditions, as demonstrated by interrogating open-source transcriptomic data, and thus patients with other conditions may also benefit from a morning rest period in a similar manner. Our findings implicate rest as a key driver of physiology, creating an entirely new field – as broad and important as diet, sleep, or exercise – and provide a strong rationale for investigation of rest-based therapy for major clinical diseases.
Authors
Cristine J. Reitz, Mina Rasouli, Faisal J. Alibhai, Tarak Nath Khatua, W. Glen Pyle, Tami A. Martino
Abstract
BRD4 is a bromodomain extra-terminal domain (BET) family member and functions primarily as a chromatin reader regulating genes involved in cell fate decisions. Here we bred Brd4f/fOx40-Cre mice in which Brd4 was conditionally deleted in OX40-expressing cells to examine the role of BRD4 in regulating immune responses. We found that the Brd4f/fOx40-Cre mice developed profound alopecia and dermatitis while other organs and tissues were not affected. Surprisingly, lineage-tracing experiments using the Rosa26f/f-Yfp mice identified a subset of hair follicle stem cells (HFSCs) that constitutively express OX40 and deletion of Brd4 specifically in such HFSCs resulted in cell death and a complete loss of skin hair growth. We also found that death of HFSCs triggered massive activation of the intra-dermal γδ T cells, which induced epidermal hyperplasia and dermatitis by producing the inflammatory cytokine IL-17. Interestingly, deletion of Brd4 in Foxp3+ Tregs, which also constitutively express OX40, compromised their suppressive functions and this in turn contributed to the enhanced activation of γδ T cells as well as the severity of dermatitis and hair follicle destruction. Thus, our data demonstrate an unexpected role of BRD4 in regulating skin follicle stem cells and skin inflammation.
Authors
Mou Wen, Yuanlin Ying, Xiang Xiao, Preston R. Arnold, Guangchuan Wang, Xiufeng Chu, Rafik M. Ghobrial, Xian C. Li
Abstract
Pancreatic ductal adenocarcinoma (PDA) remains resistant to immune therapies, largely due to robustly fibrotic and immunosuppressive tumor microenvironments. It has been postulated that excessive accumulation of immunosuppressive myeloid cells influences immunotherapy resistance and recent studies targeting macrophages in combination with checkpoint blockade have demonstrated promising preclinical results. Yet, our understanding of tumor-associated macrophage (TAM) function, complexity, and diversity in PDA remains limited. Here, analysis reveals significant macrophage heterogeneity, with bone marrow-derived monocytes serving as the primary source for immunosuppressive TAMs. These cells also serve as a primary source of TNF-α, which suppresses expression of the alarmin IL33 in carcinoma cells. Deletion of Ccr2 in genetically engineered mice decreases monocyte recruitment resulting in profoundly decreased TNF-α and increased IL33 expression, decreased metastasis, and increased survival. Moreover, intervention studies targeting CCR2 with a new orthosteric inhibitor (CCX598) renders PDA susceptible to checkpoint blockade resulting in reduced metastatic burden and increased survival. Our data indicate that this shift in anti-tumor immunity is influenced by increased levels of IL-33, which increases dendritic cell and cytotoxic T cell activity. These data demonstrate that interventions to disrupt infiltration of immunosuppressive macrophages, or their signaling, have the potential to overcome barriers to effective immunotherapeutics for PDA.
Authors
Ajay Dixit, Aaron L. Sarver, Jon Zettervall, Huocong Huang, Kexin Zheng, Rolf A. Brekken, Paolo Provenzano
Abstract
Hevin/Sparcl1 is an astrocyte-secreted protein and regulates synapse formation. Here we show that astrocytic hevin signaling plays a critical role in maintaining chronic pain. Compared to wild-type mice, hevin-null mice exhibited normal mechanical and heat sensitivity but reduced inflammatory pain. Interestingly, hevin-null mice have faster recovery than wild-type mice from neuropathic pain after nerve injury. Intrathecal injection of wild-type hevin was sufficient to induce persistent mechanical allodynia in naïve mice. In hevin-null mice with nerve injury, AAV-mediated re-expression of hevin in GFAP-expressing spinal cord astrocytes could reinstate neuropathic pain. Mechanistically, hevin is crucial for spinal cord NMDA receptor (NMDAR) signaling. Hevin potentiated NMDA currents mediated by the GluN2B-containing NMDARs. Furthermore, intrathecal injection of a neutralizing antibody against hevin alleviated acute and persistent inflammatory pain, postoperative pain, and neuropathic pain. Secreted hevin was detected in mouse cerebrospinal fluid (CSF) and nerve injury significantly increased CSF hevin abundance. Finally, neurosurgery caused rapid and substantial increases in SPARCL1/HEVIN levels in human CSF. Collectively, our findings support a critical role of hevin and astrocytes in the maintenance of chronic pain. Neutralizing of secreted hevin with monoclonal antibody may provide a new therapeutic strategy for treating acute and chronic pain and NMDAR-medicated neurodegeneration.
Authors
Gang Chen, Jing Xu, Hao Luo, Xin Luo, Sandeep K. Singh, Juan J. Ramirez, Michael L. James, Joseph P. Mathew, Miles Berger, Cagla Eroglu, Ru-Rong Ji
Abstract
TP53 mutation (TP53mut) is one of the most important driver events facilitating tumorigenesis, which could induce a series of chain reactions to promote tumor malignant transformation. However, the malignancy progression patterns under TP53 mutation still remain less known. Clarifying the molecular landscapes of TP53mut tumors will help us understand the process of tumor development and aid precise treatment. Here, we distilled genetic and epigenetic features altered in TP53mut cancers for cluster-of-cluster analysis. Using integrated classification, we derived five different subtypes of TP53mut patients. These subtypes have distinct features in genomic alteration, clinical relevance, microenvironment dysregulation and potential therapeutics. Among the five subtypes, COCA3 was identified as the subtype with worst prognosis, causing an immunosuppressive microenvironment and immunotherapeutic resistantance. Further drug efficacy research highlighted olaparib as the most promising therapeutic agents for COCA3 tumors. Importantly, the therapeutic efficacy of olaparib in COCA3 and immunotherapy in non-COCA3 tumors was validated in vivo experiment. Summarily, our study first explored the important molecular events and developed a subtype classification system with distinct targeted therapy strategies for different subtypes of TP53mut tumors. These multi-omics classification systems provided a valuable resource that significantly expands the knowledge of TP53mut tumors and might eventually benefit in clinical practice.
Authors
Xin Chen, Tianqi Liu, Wu Jianqi, Chen Zhu, Gefei Guan, Cunyi Zou, Qing Guo, Xiaolin Ren, Chen Li, Peng Cheng, Wen Cheng, Anhua Wu
Abstract
Preeclampsia is a serious pregnancy disorder that lacks effective treatments other than delivery. Improper sensing of oxygen changes during placentation by prolyl hydroxylases (PHD), specifically PHD2, causes placental Hypoxia-Inducible Factor-1 (HIF1) buildup and abnormal downstream signaling in early-onset preeclampsia; yet therapeutic targeting of HIF1 has never been attempted. Here we generated a conditional (placenta-specific) knockout of Phd2 in mice (Phd2-/- cKO) to reproduce HIF1 excess and to assess anti-HIF therapy. Conditional deletion of Phd2 in the junctional zone (JZ) during pregnancy increased placental HIF1 content, resulting in abnormal placentation, impaired remodeling of the uterine spiral arteries, and fetal growth restriction. Pregnant dams developed new-onset hypertension at mid-gestation (E9.5) in addition to proteinuria and renal and cardiac pathology, hallmarks of severe preeclampsia in humans. Daily injection of acriflavine, a small-molecule inhibitor of HIF1, to pregnant Phd2-/- cKO mice from E7.5 (prior to hypertension) or E10.5 (after hypertension has been established) to E14.5 corrected placental dysmorphologies and improved fetal growth. Moreover, it reduced maternal blood pressure and reverted renal and myocardial pathology. Thus, therapeutic targeting of the HIF pathway may improve placental development and function, as well as maternal and fetal health, in preeclampsia.
Authors
Julien Sallais, Chanho Park, Sruthi Alahari, Tyler Porter, Ruizhe Liu, Merve Kurt, Abby Farrell, Martin Post, Isabella Caniggia
Abstract
Acute graft-versus-host disease (aGvHD) is a life-threatening complication of allogeneic hematopoietic cell transplantation (allo-HCT) inflicted by alloreactive T cells primed in secondary lymphoid organs (SLOs) and subsequent damage to aGvHD target tissues. In recent years, regulatory T cell (Treg) transfer and/or expansion has emerged as a promising therapy to modulate aGvHD. However, cellular niches essential for fostering Tregs to prevent aGvHD have not been explored, yet. Here, we tested whether and to what extent MHC class II (MHCII) expressed on Ccl19+ fibroblastic reticular cells (FRCs) shape the donor CD4+ T cell response during aGvHD. Animals lacking MHCII expression on Ccl19-Cre-expressing FRCs (MHCIIΔCcl19) showed aberrant CD4+ T cells activation in the effector phase resulting in exacerbated aGvHD that was associated with significantly reduced expansion of Foxp3+ Tregs and invariant natural killer T (iNKT) cells. Skewed Treg maintenance in MHCIIΔCcl19 mice resulted in loss of protection from aGvHD provided by adoptively transferred donor Tregs. In contrast, although FRCs upregulated co-stimulatory surface receptors, degraded and processed exogenous antigens after myeloablative irradiation, FRCs were dispensable to activate alloreactive CD4+ T cells in two mouse models of aGvHD. In sum, these data reveal an immunoprotective, MHCII-mediated function of FRC niches in secondary lymphoid organs (SLOs) after allo-HCT and highlights a hitherto unknown framework of cellular and molecular interactions that regulate CD4+ T cell alloimmunity.
Authors
Haroon Shaikh, Joern Pezoldt, Zeinab Mokhtari, Juan Gamboa Vargas, Duc-Dung Le, Josefina Peña Mosca, Estibaliz Arellano-Viera, Michael A.G. Kern, Caroline Graf, Niklas Beyersdorf, Manfred B. Lutz, Angela Riedel, Maike Büttner-Herold, Alma Zernecke, Hermann Einsele, Antoine-Emmanuel Saliba, Burkhard Ludewig, Jochen Huehn, Andreas Beilhack
Abstract
The DNA methyltransferase inhibitor decitabine has classically been used to reactivate silenced genes and as a pre-treatment for anti-cancer therapies. In a new variation of this idea, this study explores the concept of adding low-dose decitabine following administration of chemotherapy to bolster therapeutic efficacy. We find that addition of decitabine following treatment with the chemotherapy gemcitabine improves survival and slows tumor growth in a mouse model of high-grade sarcoma. Unlike prior studies in epithelial tumor models, low-dose decitabine did not induce a robust anti-tumor T cell response in sarcoma. Furthermore, low-dose decitabine synergizes with gemcitabine independently of the immune system. Mechanistic analyses demonstrate that the combination therapy induces bi-phasic cell cycle arrest and apoptosis. Therapeutic efficacy was found to be sequence dependent, with gemcitabine priming cells for treatment with decitabine through inhibition of ribonucleotide reductase. This study identifies a unique application of low-dose decitabine to augment the cytotoxic effects of conventional chemotherapy in an immune-independent manner. The concepts explored in this study represent a promising new paradigm for cancer treatment by augmenting chemotherapy through addition of low-dose decitabine to increase tolerability and improve patient response. These findings have widespread implications for the treatment of sarcomas and other aggressive malignancies.
Authors
Wade R. Gutierrez, Amanda Scherer, Jeffrey D. Rytlewski, Emily A. Laverty, Alexa P. Sheehan, Gavin R. McGivney, Qierra R. Brockman, Vickie Knepper-Adrian, Grace A. Roughton, Dawn E. Quelle, David J. Gordon, Varun Monga, Rebecca D. Dodd
Abstract
The fluid covering the surface of airway epithelia represents a first barrier against pathogens. The chemical and physical properties of the airway surface fluid are controlled by the activity of ion channels and transporters. In cystic fibrosis (CF), loss of CFTR chloride channel function causes airway surface dehydration, bacterial infection, and inflammation. We investigated the effects of IL-17A plus TNF-α, two cytokines with a relevant role in CF and other chronic lung diseases. Transcriptome analysis revealed a profound change with upregulation of several genes involved in ion transport, anti-bacterial defense, and neutrophil recruitment. At the functional level, bronchial epithelia treated in vitro with the cytokine combination showed upregulation of ENaC sodium channel, ATP12A proton pump, ADRB2 beta-adrenergic receptor, and SLC26A4 anion exchanger. The overall result of IL-17A/TNF-α treatment was hyperviscosity of the airway surface as demonstrated by fluorescence recovery after photobleaching (FRAP) experiments. Importantly, stimulation with a beta-adrenergic agonist switched airway surface to a low viscosity state in non-CF but not in CF epithelia. Our study suggests that CF lung disease is sustained by a vicious cycle in which epithelia cannot exit from the hyperviscous state thus perpetuating the proinflammatory airway surface condition.
Authors
Daniela Guidone, Martina Buccirossi, Paolo Scudieri, Michele Genovese, Sergio Sarnataro, Rossella De Cegli, Federico Cresta, Vito Terlizzi, Gabrielle Planelles, Gilles Crambert, Isabelle Sermet-Gaudelus, Luis J.V. Galietta
Pathogenicity and impact of HLA class I alleles in aplastic anemia patients of different ethnicities
Abstract
Acquired aplastic anemia (AA) is caused by autoreactive T-cell-mediated destruction of early hematopoietic cells. Somatic loss of human leukocyte antigen (HLA) Class I alleles was identified as a mechanism of immune escape in surviving hematopoietic cells of some AA patients. However, pathogenicity, structural characteristics and clinical impact of specific HLA alleles in AA remain poorly understood. Here, we evaluated somatic HLA loss in 505 AA patients from two multi-institutional cohorts. Using a combination of HLA mutation frequencies, peptide-binding structures, and association with AA in an independent cohort of 6,323 patients from the National Marrow Donor Program, we identified 19 AA risk alleles and 12 non-risk alleles and established a novel AA HLA pathogenicity stratification. Our results define pathogenicity for the majority of common HLA-A/B alleles across diverse populations. Our study demonstrates that HLA alleles confer different risks of developing AA, but once AA develops, specific alleles are not associated with response to immunosuppression or trans-plant outcomes. However, higher pathogenicity alleles, particularly HLA-B*14:02, are associated with higher rates of clonal evolution in adult AA patients. Our study provides novel insights into the immune pathogenesis of AA, opening the door to future autoantigen identification and improved under-standing of clonal evolution in AA.
Authors
Timothy S. Olson, Benjamin F. Frost, Jamie L. Duke, Marian Dribus, Hongbo M. Xie, Zachary D. Prudowsky, Elissa Furutani, Jonas Gudera, Yash B. Shah, Deborah Ferriola, Amalia Dinou, Ioanna Pagkrati, Soyoung Kim, Yixi Xu, Meilun He, Shannon Zheng, Sally Nijim, Ping Lin, Chong Xu, Taizo Nakano, Joseph H. Oved, Beatriz M. Carreno, Yung-Tsi Bolon, Shahinaz M. Gadalla, Steven G.E. Marsh, Sophie Paczesny, Stephanie J. Lee, Dimitrios S. Monos, Akiko Shimamura, Alison A. Bertuch, Loren Gragert, Stephen Spellman, Daria V. Babushok
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