Chronic allergic inflammatory diseases are a major cause of morbidity, allergic asthma alone affecting over 300 million people worldwide. Epidemiological studies demonstrate that environmental stimuli are associated with either promotion or prevention of disease. Major reductions in asthma prevalence are documented in European and US farming communities. Protection is associated with exposure of mothers during pregnancy to microbial breakdown products present in farm dusts and unprocessed foods, and enhancement of innate immune competence in the children. We sought to develop a scientific rationale for progressing these findings towards clinical application for primary disease prevention. Treatment of pregnant mice with a defined clinically-approved immune-modulator was shown to markedly reduce susceptibility of their offspring to development of the hallmark clinical features of allergic airway inflammatory disease. Mechanistically, offspring displayed enhanced dendritic cell-dependent airway mucosal immune surveillance function, which resulted in more efficient generation of mucosal-homing T-regulatory cells in response to local inflammatory challenge. We provide evidence that the principal target for maternal treatment effects was the fetal dendritic cell progenitor compartment, equipping the offspring for accelerated functional maturation of the airway mucosal dendritic cell network following birth. These data provide proof-of-concept supporting the rationale for development of transplacental immune reprogramming approaches for primary disease prevention.
Kyle T. Mincham, Naomi M. Scott, Jean-Francois Lauzon-Joset, Jonatan Leffler, Alexander N. Larcombe, Philip A. Stumbles, Sarah A. Robertson, Christian Pasquali, Patrick G. Holt, Deborah H. Strickland
BACKGROUND. Evidence from rodent studies indicates that the sympathetic nervous system (SNS) regulates bone metabolism, principally via β2-adrenergic receptors (β2-ARs). Given conflicting human data, we used multiple approaches to evaluate the role of the SNS in regulating human bone metabolism. METHODS. (1) Bone biopsies were obtained from 19 young and 19 old women for assessment of ADRB1, ADRB2, and ADRB3 mRNA expression; (2) the relationship of β-blocker use to bone microarchitecture was assessed by high resolution-peripheral quantitative computed tomography in a population sample of 248 subjects; and (3) 155 postmenopausal women were randomized to one of five treatment groups for 20 weeks: placebo; propranolol, 20 mg twice a day (BID); propranolol, 40 mg BID; atenolol, 50 mg/d; and nebivolol, 5 mg/d. We took advantage of the β1-AR selectivity gradient of these drugs (propranolol [non-selective] << atenolol [relatively β1-AR selective] < nebivolol [highly β1-AR selective]) to define the β-AR selectivity for SNS effects on bone. RESULTS. (1) ADRB1and ADRB2, but not ADRB3, were expressed in human bone; (2) patients treated clinically with β1-AR selective blockers had better bone microarchitecture than non-users; and (3) relative to placebo, atenolol and nebivolol, but not propranolol, reduced the bone resorption marker serum C-telopeptide of type I collagen (by 19.5% and 20.6%, respectively; P < 0.01) and increased ultra-distal radius BMD (by 3.6% and 2.9%; P < 0.01 and P < 0.05, respectively). CONCLUSIONS. These three independent lines of evidence strongly support a role for adrenergic signaling in regulating bone metabolism in humans, principally via β1-ARs. TRIAL REGISTRATION. ClinicalTrials.gov NCT02467400. FUNDING. This research was supported by NIH grants AG004875, AR027065, and the Mayo Clinic CTSA (UL1 TR002377).
Sundeep Khosla, Matthew T. Drake, Tammie L. Volkman, Brianne S. Thicke, Sara J. Achenbach, Elizabeth J. Atkinson, Michael J. Joyner, Clifford J. Rosen, David G. Monroe, Joshua N. Farr
It is suggested that subtyping of complex inflammatory diseases can be based on genetic susceptibility and relevant environmental exposure (G+E). We propose that using matched cellular phenotypes in human subjects and corresponding pre-clinical models with the same G+E combinations are useful to this end. As an example, defective Paneth cells can subtype Crohn's disease (CD) subjects; Paneth cell defects have been linked to multiple CD susceptibility genes and are associated with poor outcome. We hypothesized that CD susceptibility genes interact with cigarette smoking, a major CD environmental risk factor, to trigger Paneth cell defects. We found that both CD subjects and mice with ATG16L1T300A (T300A; a prevalent CD susceptibility allele) developed Paneth cell defects triggered by tobacco smoke. Transcriptional analysis of full thickness ileum and Paneth cell-enriched crypt base cells showed the T300A-smoking combination altered distinct pathways, including pro-apoptosis, metabolic dysregulation, and selective down-regulation of the PPARγ pathway. Pharmacologic intervention by either apoptosis inhibitor or PPARγ agonist rosiglitazone prevented smoking-induced crypt apoptosis and Paneth cell defects in T300A mice and mice with conditional Paneth cell-specific knockout of Atg16l1. This study demonstrates how explicit G+E can drive disease relevant phenotype, and provides rational strategies to identify actionable targets.
Ta-Chiang Liu, Justin T. Kern, Kelli L. VanDussen, Shanshan Xiong, Gerard E. Kaiko, Craig B. Wilen, Michael W. Rajala, Roberta Caruso, Michael J. Holtzman, Feng Gao, Dermot P.B. McGovern, Gabriel Nunez, Richard D. Head, Thaddeus S. Stappenbeck
Inflammation occurs in all tissues in response to injury or stress and is the key process underlying hepatic fibrogenesis. Targeting chronic and uncontrolled inflammation is one strategy to prevent liver injury and fibrosis progression. Here, we demonstrate that triggering receptor expressed on myeloid cells-1 (TREM-1), an amplifier of inflammation, promotes liver disease by intensifying hepatic inflammation and fibrosis. In the liver, TREM-1 expression is limited to liver macrophages and monocytes and is highly upregulated on Kupffer cells, circulating monocytes, and monocyte-derived macrophages in a mouse model of chronic liver injury and fibrosis induced by carbon tetrachloride (CCl4) administration. TREM-1 signaling promotes pro-inflammatory cytokine production and mobilization of inflammatory cells to the site of injury. Deletion of Trem1 reduced liver injury, inflammatory cell infiltration, and fibrogenesis. Reconstitution of Trem1-deficient mice with Trem1-sufficient Kupffer cells restored recruitment of inflammatory monocytes and severity of liver injury. Markedly increased infiltration of liver fibrotic areas with TREM-1-positive Kupffer cells and monocytes/macrophages was found in patients with hepatic fibrosis. Our data support a role of TREM-1 in liver injury and hepatic fibrogenesis and suggests that TREM-1 is a master regulator of Kupffer cell activation, which escalates chronic liver inflammatory responses, activates hepatic stellate cells, and reveals a novel mechanism of promotion of liver fibrosis.
Anh Thu Nguyen-Lefebvre, Ashwin Ajith, Vera Portik-Dobos, Daniel David Horuzsko, Ali Syed Arbab, Amiran Dzutsev, Ramses Sadek, Giorgio Trinchieri, Anatolij Horuzsko
Human endogenous retroviruses (hERVs) are remnants of exogenous retroviruses that have integrated into the genome throughout evolution. We developed a computational workflow, hervQuant, which identified over 3,000 transcriptionally active hERVs within The Cancer Genome Atlas (TCGA) pan-cancer RNA-seq database. hERV expression was associated with clinical prognosis in several tumor types, most significantly clear cell renal cell carcinoma (ccRCC). We explored two mechanisms by which hERV expression may influence the tumor-immune microenvironment in ccRCC: through 1) RIG-I-like signaling, and 2) retroviral antigen activation of adaptive immunity. We demonstrated the ability of hERV signatures associated with these immune mechanisms to predict patient survival in ccRCC, independent of clinical staging and molecular subtyping. We identified potential tumor-specific hERV epitopes with evidence of translational activity through the use of a ccRCC Ribo-seq dataset, validated their ability to bind HLA in vitro, and identified presence of MHC tetramer-positive T cells against predicted epitopes. hERV sequences identified through this screening approach were significantly more highly expressed in ccRCC tumors responsive to treatment with programmed death receptor-1 (PD-1) inhibition. hervQuant provides new insights into the role of hERVs within the tumor-immune microenvironment as well as evidence for hERV expression-based biomarkers for patient prognosis and response to immunotherapy.
Christof C. Smith, Kathryn E. Beckermann, Dante S. Bortone, Aguirre A. de Cubas, Lisa M. Bixby, Samuel J. Lee, Anshuman Panda, Shridar Ganesan, Gyan Bhanot, Eric M. Wallen, Matthew I. Milowsky, William Y. Kim, W. Kimryn Rathmell, Ronald Swanstrom, Joel S. Parker, Jonathan S. Serody, Sara R. Selitsky, Benjamin G. Vincent
Renin cells are crucial for survival: they control fluid-electrolyte and blood pressure homeostasis, vascular development, regeneration, and oxygen delivery to tissues. During embryonic development, renin cells are progenitors for multiple cell types which retain the memory of the renin phenotype. When there is a threat to survival, those descendants are transformed and reenact the renin phenotype to restore homeostasis. We tested the hypothesis that the molecular memory of the renin phenotype resides in unique regions and states of these cells’ chromatin. Using renin cells at various stages of stimulation, we identified regions in the genome where the chromatin is open for transcription, mapped histone modifications characteristic of active enhancers such as H3K27ac and deposition of transcriptional activators such a Med1 whose deletion results in ablation of Renin expression and low blood pressure. Using the rank ordering of super-enhancers, epigenetic re-writing, and enhancer deletion analysis, we found that renin cells harbor a unique set of super-enhancers that determine their identity. The most prominent Renin super-enhancer may act as a chromatin sensor of signals that convey the physiologic status of the organism and is responsible for the transformation of renin cell descendants to the renin phenotype, a fundamental process to ensure homeostasis.
Maria Florencia Martinez, Silvia Medrano, Evan A. Brown, Turan Tufan, Stephen Shang, Nadia Bertoncello, Omar Guessoum, Mazhar Adli, Brian C. Belyea, Maria Luisa S. Sequeira Lopez, R. Ariel Gomez
Mutant KRAS drives glycolytic flux in lung cancer, potentially impacting aberrant protein glycosylation. Recent evidence suggests aberrant KRAS drives flux of glucose into the hexosamine biosynthetic pathway (HBP). HBP is required for various glycosylation processes, such as protein N- or O-glycosylation and glycolipid synthesis. However, its function during tumorigenesis is poorly understood. One contributor and proposed target of KRAS driven cancers is a developmentally conserved epithelial plasticity program called epithelial-mesenchymal transition (EMT). Here we show in novel autochthonous mouse models that EMT accelerates KrasG12D lung tumorigenesis by upregulating expression of key enzymes of the HBP pathway. We demonstrate that HBP is required for suppressing KrasG12D-induced senescence, and targeting HBP significantly delays KrasG12D lung tumorigenesis. To explore the mechanism, we investigated protein glycosylation downstream of HBP and found elevated levels of O-linked β-N-acetylglucosamine (O-GlcNAcylation) post-translational modification on intracellular proteins. O-GlcNAcylation suppressed KrasG12D oncogene-induced senescence (OIS) and accelerates lung tumorigenesis. Conversely, loss of O-GlcNAcylation delays lung tumorigenesis. O-GlcNAcylation of proteins SNAI1 and c-Myc correlates with the EMT-HBP axis and accelerated lung tumorigenesis. Our results demonstrate that O-GlcNAcylation is sufficient and required to accelerate KrasG12D lung tumorigenesis in vivo, which is reinforced by epithelial plasticity programs.
Kekoa Taparra, Hailun Wang, Reem Malek, Audrey Lafargue, Mustafa A. Barbhuiya, Xing Wang, Brian W. Simons, Matthew Ballew, Katriana Nugent, Jennifer Groves, Russell D. Williams, Takumi Shiraishi, James Verdone, Gokben Yildirir, Roger Henry, Bin Zhang, John Wong, Ken Kang-Hsin Wang, Barry D. Nelkin, Kenneth J. Pienta, Dean Felsher, Natasha E. Zachara, Phuoc T. Tran
First generation immune checkpoint inhibitors including anti-CTLA-4 and anti-PD-1 antibodies have led to major clinical progress, yet resistance frequently leads to treatment failure. Thus, new targets acting on T cells are needed. CD33-related Siglecs are pattern recognition immune receptors binding to a range of sialoglycan ligands, which appear to function as self-associated molecular patterns (SAMPs) that suppress autoimmune responses. Siglecs are expressed at very low levels on normal T cells, and these receptors were not yet considered as interesting targets on T cells for cancer immunotherapy. Here, we show an upregulation of Siglecs including Siglec-9 on tumor-infiltrating T cells from non-small cell lung (NSCLC), colorectal and ovarian cancer patients. Siglec-9 expressing T cells co-expressed several inhibitory receptors including PD-1. Targeting of the sialoglycan-SAMP/Siglec pathway in vitro and in vivo resulted in increased anti-cancer immunity. T cell expression of Siglec-9 in NSCLC patients correlated with a reduced survival, and Siglec-9 polymorphisms showed associations with the risk of developing lung and colorectal cancer. Our data identify the sialoglycan-SAMP/Siglec pathway as new potential target to improve T cell activation for immunotherapy.
Michal A. Stanczak, Shoib S. Siddiqui, Marcel P. Trefny, Daniela S. Thommen, Kayluz Frias Boligan, Stephan von Gunten, Alexandar Tzankov, Lothar Tietze, Didier Lardinois, Viola Heinzelmann-Schwarz, Michael S. von Bergwelt-Baildon, Wu Zhang, Heinz-Josef Lenz, Younghan Han, Christopher I. Amos, Mohammedyaseen Syedbasha, Adrian Egli, Frank Stenner, Daniel E. Speiser, Ajit Varki, Alfred Zippelius, Heinz Läubli
While T cells are important for the pathogenesis of systemic lupus erythematosus (SLE) and lupus nephritis, little is known about how T cells function after infiltrating the kidney. The current paradigm suggests that kidney infiltrating T cells (KITs) are activated effector cells contributing to tissue damage and ultimately organ failure. Herein, we demonstrate that the majority of CD4+ and CD8+ KITs in three murine lupus models are not effector cells, as hypothesized, but rather expressed multiple inhibitory receptors and proved highly dysfunctional with reduced cytokine production and proliferative capacity. Mechanistically this was linked directly to metabolic and specifically mitochondrial dysfunction. This was driven by the expression of an “exhausted” transcriptional signature. Our data thus reveal that the tissue parenchyma has the capability to suppress T cell responses and limit damage to self. These findings open novel avenues for the treatment of autoimmunity based on selectively exploiting the exhausted phenotype of tissue-infiltrating T cells.
Jeremy S. Tilstra, Lyndsay Avery, Ashley V. Menk, Rachael A. Gordon, Shuchi Smita, Lawrence P. Kane, Maria Chikina, Greg M. Delgoffe, Mark J. Shlomchik
Regulatory T-cells (Treg) are critical for maintaining immune homeostasis. However, current Treg immunotherapies do not optimally treat inflammatory diseases in patients. Understanding the cellular processes that control Treg function may allow for the augmentation of therapeutic efficacy. In contrast to activated conventional T-cells, where protein kinase C-θ (PKC-θ) localizes to the contact-point between T-cells and antigen-presenting cells, in human and mouse Treg, PKC-θ localizes to the opposite end of the cell in the distal pole complex (DPC). Here, using a phosphoproteomic screen, we identified the intermediate filament vimentin as a PKC-θ phospho-target and show that vimentin forms a DPC superstructure on which PKC-θ accumulates. Treatment of mouse Treg with either a clinically relevant PKC-θ inhibitor or vimentin siRNA disrupted vimentin and enhanced Treg metabolic and suppressive activity. Moreover, vimentin-disrupted mouse Treg were significantly better than controls in suppressing alloreactive T-cell priming in graft-versus-host disease, and graft-versus-host disease lethality, using a complete MHC mismatch mouse model of acute graft-versus-host disease (C57BL/6 donor in to BALB/c host). Interestingly, vimentin disruption augmented suppressor function of PKC-θ-deficient mouse Treg. This suggests that enhanced Treg activity after PKC-θ inhibition is secondary to effects on vimentin, not just PKC-θ kinase activity inhibition. Our data demonstrated that vimentin is a key metabolic and functional controller of Treg activity, and provide proof-of-principle that disrupting vimentin is a feasible, translationally relevant method to enhance Treg potency.
Cameron McDonald-Hyman, James T. Muller, Michael Loschi, Govindarajan Thangavelu, Asim Saha, Sudha Kumari, Dawn K. Reichenbach, Michelle J. Smith, Guoan Zhang, Brent H. Koehn, Jiqiang Lin, Jason S. Mitchell, Brian T. Fife, Angela Panoskaltsis-Mortari, Colby J. Feser, Andrew Kemal Kirchmeier, Mark J. Osborn, Keli L. Hippen, Ameeta Kelekar, Jonathan S. Serody, Laurence A. Turka, David H. Munn, Hongbo Chi, Thomas A. Neubert, Michael L. Dustin, Bruce R. Blazar
Graft-versus-host disease (GVHD) in the gastrointestinal (GI) tract remains the major cause of morbidity and non-relapse mortality after bone marrow transplantation (BMT). The Paneth cell protein, regenerating islet-derived 3-alpha (REG3α), is a biomarker specific for GI GVHD. REG3α serum levels rose in the systematic circulation as GVHD progressively destroyed Paneth cells and reduced GI epithelial barrier function. Paradoxically, GVHD suppressed intestinal REG3γ (the mouse homologue of human REG3α), and the absence of REG3γ in BMT recipients intensified GVHD but did not change the composition of the microbiome. IL-22 administration restored REG3γ production and prevented apoptosis of both intestinal stem cells (ISCs) and Paneth cells, but this protection was completely abrogated in Reg3g−/− mice. In vitro, addition of REG3α reduced the apoptosis of colonic cell lines. Strategies that increase intestinal REG3α/γ to promote crypt regeneration may offer a novel, non-immunosuppressive approach for GVHD and perhaps for other diseases involving the ISC niche such as inflammatory bowel disease.
Dongchang Zhao, Yeung-Hyen Kim, Seihwan Jeong, Joel K. Greenson, Mohammed S. Chaudhry, Matthias Hoepting, Erik R. Anderson, Marcel R.M. van den Brink, Jonathan U. Peled, Antonio L.C. Gomes, Ann E. Slingerland, Michael J. Donovan, Andrew C. Harris, John E. Levine, Umut Özbek, Lora V. Hooper, Thaddeus S. Stappenbeck, Aaron M. Ver Heul, Ta-Chiang Liu, Pavan Reddy, James L.M. Ferrara
Previous findings showed that in mice, complete knockout of activity-dependent neuroprotective protein (ADNP) abolishes brain formation, while haploinsufficiency (Adnp+/–) causes cognitive impairments. We hypothesized that mutations in ADNP lead to a developmental/autistic syndrome in children. Indeed, recent phenotypic characterization of children harboring ADNP mutations (ADNP syndrome children) revealed global developmental delays and intellectual disabilities, including speech and motor dysfunctions. Mechanistically, ADNP includes a SIP motif embedded in the ADNP-derived snippet, drug candidate NAP (NAPVSIPQ also known as CP201), which binds to microtubule end binding protein 3, essential for dendritic spine formation. Here, we established a unique neuronal membrane tagged green fluorescent protein expressing Adnp+/– mouse line allowing in vivo synaptic pathology quantification. We discovered that Adnp deficiency reduced dendritic spine density and altered synaptic gene expression, both of which were partly ameliorated by NAP treatment. Adnp+/– mice further exhibited global developmental delays, vocalization impediments, gait/motor dysfunctions and social/object memory impairments, all partially reversed by daily NAP administration (systemic/nasal). In conclusion, we now connected ADNP-related synaptic pathology to developmental/behavioral outcomes, establishing NAP in vivo target engagement and identifying potential biomarkers. Together, these studies pave the path toward clinical development of NAP (CP201) in the ADNP syndrome.
Gal Hacohen-Kleiman, Shlomo Sragovich, Gidon Karmon, Andy Y. L. Gao, Iris Grigg, Metsada Pasmanik-Chor, Albert Le, Vlasta Korenková, R. Anne McKinney, Illana Gozes
B cells are increasingly recognised to play an important role in the ongoing control of hepatitis B virus (HBV). The development of antibodies against the viral surface antigen (HBsAg) constitutes the hallmark of resolution of acute infection and is a therapeutic goal for functional cure of chronic HBV (CHB). We characterised B cells directly ex vivo from the blood and liver of patients with CHB to investigate constraints on their antiviral potential. Unexpectedly, we found that HBsAg-specific B cells persisted in the blood and liver of many patients with CHB and were enriched for T-bet, a signature of antiviral potential in B cells. However purified, differentiated HBsAg-specific B cells from patients with CHB had defective antibody production, consistent with undetectable anti-HBs antibodies in vivo. HBsAg-specific and global B cells had an accumulation of CD21–CD27– atypical memory B cells (atMBC) with high expression of inhibitory receptors including PD-1. These atMBC demonstrated altered signalling, homing, differentiation into antibody-producing cells, survival and antiviral/pro-inflammatory cytokine production, that could be partially rescued by PD-1 blockade. Analysis of B cells within healthy and HBV-infected livers implicated the combination of this tolerogenic niche and HBV infection in driving PD-1hiatMBC and impairing B cell immunity.
Alice R. Burton, Laura J. Pallett, Laura E. McCoy, Kornelija Suveizdyte, Oliver E. Amin, Leo Swadling, Elena Alberts, Brian R. Davidson, Patrick T.F. Kennedy, Upkar S. Gill, Claudia Mauri, Paul A. Blair, Nadege Pelletier, Mala K. Maini
Chronic HBV (CHB) infection suppresses virus-specific T cells, but its impact on humoral immunity has been poorly analyzed. Here, we developed a dual staining method, which utilizes HBsAg labelled with fluorochromes as “baits”, for specific ex vivo detection of HBsAg-specific B cells and analysis of their quantity, function and phenotype. We studied healthy vaccinated subjects (n=18) and patients with resolved (n=21), acute (n=11) or chronic (n=96) HBV infection and observed that frequencies of circulating HBsAg-specific B cells are independent of the HBV infection status. In contrast, serum HBsAg presence affects function and phenotype of HBsAg-specific B cells that were unable to mature in vitro into antibody-secreting cells and displayed an increased expression of markers linked to hyperactivation (CD21low) and exhaustion (PD-1). Importantly, B cell alterations were not limited to HBsAg-specific B cells but affected the global B cell population. HBsAg-specific B cell maturation could be partially restored by a method involving the combination of IL-2, IL-21 and CD40L-expressing feeder cells, and further boosted by addition of anti-PD-1 antibodies.In conclusion, HBV infection has a marked impact on global and HBV-specific humoral immunity, yet HBsAg-specific B cells are amenable to a partial rescue by B cell maturing cytokines and PD-1 blockade.
Loghman Salimzadeh, Nina Le Bert, Charles-A. Dutertre, Upkar S. Gill, Evan W. Newell, Christian Frey, Magdeleine Hung, Nikolai Novikov, Simon Fletcher, Patrick T.F. Kennedy, Antonio Bertoletti
Zika virus (ZIKV) is a teratogenic mosquito-borne flavivirus which can be sexually transmitted from man to woman. High viral loads and prolonged viral shedding in semen suggest that ZIKV replicates within the human male genital tract, but its target organs are unknown. Using ex vivo infection of organotypic cultures, we demonstrated here that ZIKV replicates in human testicular tissue and infects a broad range of cell types, including germ cells, which we also identified as infected in the semen from ZIKV-infected donors. ZIKV had no major deleterious effect on the morphology and hormonal production of the human testis explants. Infection induced a broad antiviral response but no interferon up-regulation and minimal pro-inflammatory response in testis explants, with no cytopathic effect. Finally, we studied ZIKV infection in mouse testis, and compared it to human infection. This study provides key insights into how ZIKV may persist in semen and alter semen parameters, as well as a valuable tool for testing antiviral agents.
Giulia Matusali, Laurent Houzet, Anne-Pascale Satie, Dominique Mahé, Florence Aubry, Thérèse Couderc, Julie Frouard, Salomé Bourgeau, Karim Bensalah, Sylvain Lavoué, Guillaume Joguet, Louis Bujan, André Cabié, Gleide F. Avelar, Marc Lecuit, Anna Le Tortorec, Nathalie Dejucq-Rainsford
Prostate cancer is an androgen-dependent disease subject to interactions between the tumor epithelia and its microenvironment. Here, we found epigenetic changes in cancer-associated prostatic fibroblasts (CAF) initiated a cascade of stromal-epithelial interactions. This facilitated lethal prostate cancer growth and development of resistance to androgen signaling deprivation therapy (ADT). We identified that a Ras inhibitor, RASAL3, is epigenetically silenced in human prostatic CAF, leading to oncogenic Ras activity driving macropinocytosis-mediated glutamine synthesis. Interestingly, ADT further promoted RASAL3 epigenetic silencing and glutamine secretion by prostatic fibroblasts. In a orthotopic xenograft model, subsequent inhibition of macropinocytosis and glutamine transport resulted in antitumor effects. Stromal glutamine served as a source of energy through anaplerosis and as a mediator of neuroendocrine differentiation for prostate adenocarcinoma. Antagonizing the uptake of glutamine restored sensitivity to ADT in a castrate resistant xenograft model. In validating these findings, we found that prostate cancer patients on ADT with therapeutic resistance had elevated blood glutamine levels compared to those with therapeutically responsive disease (odds ratio = 7.451, P = 0.02). Identification of epigenetic regulation of RAS activity in prostatic CAF revealed RASAL3 as a sensor for metabolic and neuroendocrine reprogramming in prostate cancer patients failing ADT.
Rajeev Mishra, Subhash Haldar, Veronica Placencio, Anisha Madhav, Krizia Rohena-Rivera, Priyanka Agarwal, Frank Duong, Bryan Angara, Manisha Tripathi, Zhenqiu Liu, Roberta A. Gottlieb, Shawn Wagner, Edwin M. Posadas, Neil A. Bhowmick
Movement of circulating fatty acids (FAs) to parenchymal cells requires their transfer across the endothelial cell (EC) barrier. The multi-ligand receptor cluster of differentiation 36 (CD36) facilitates tissue FA uptake and is expressed in ECs and parenchymal cells such as myocytes and adipocytes. Whether tissue uptake of FAs is dependent on EC or parenchymal cell CD36, or both, is unknown. Using a cell-specific deletion approach, we show that EC, but not parenchymal cell CD36 deletion increased fasting plasma FAs and postprandial triglycerides. EC-Cd36 knockout mice had reduced uptake of radiolabeled long chain FAs into heart, skeletal muscle, and brown adipose tissue; these uptake studies were replicated using [11C]palmitate PET scans. High fat diet-fed EC-CD36 deficient mice had improved glucose tolerance and insulin sensitivity. Both EC and cardiomyocyte (CM) deletion of CD36 reduced heart lipid droplet accumulation after fasting, but CM deletion did not affect heart glucose or FA uptake. Heart expression of several genes modulating glucose metabolism and insulin action increased with EC-CD36 deletion, but decreased with CM deletion. In conclusion, EC CD36 acts as a gatekeeper for parenchymal cell FA uptake, with important downstream effects on glucose utilization and insulin action.
Ni-Huiping Son, Debapriya Basu, Dmitri Samovski, Terri A. Pietka, Vivek S. Peche, Florian Willecke, Xiang Fang, Shui-Qing Yu, Diego Scerbo, Hye Rim Chang, Fei Sun, Svetlana Bagdasarov, Konstantinos Drosatos, Steve T. Yeh, Adam E. Mullick, Kooresh I. Shoghi, Namrata Gumaste, KyeongJin Kim, Lesley-Ann M. Huggins, Tenzin Lhakhang, Nada A. Abumrad, Ira J. Goldberg
BACKGROUND. Intravenous immunoglobulin (IVIg), plasma exchange and immunoadsorption are frequently used in the management of severe autoimmune diseases mediated by pathogenic IgG autoantibodies. These approaches to modulate IgG levels can however be associated with some severe adverse reactions and significant burden to patients. Targeting the neonatal Fc receptor (FcRn) presents an innovative and potentially more effective, safer, and convenient alternative for clearing pathogenic IgGs. METHODS. A randomized, double-blind, placebo-controlled first-in-human study was conducted in 62 healthy volunteers to explore single and multiple ascending intravenous doses of the FcRn antagonist efgartigimod. The study objectives were to assess the safety, tolerability, pharmacokinetics, pharmacodynamics, and immunogenicity. The findings of this study were compared with the pharmacodynamics profile elicited by efgartigimod in cynomolgus monkeys. RESULTS. Efgartigimod treatment resulted in a rapid and specific clearance of serum IgG levels in both cynomolgus monkeys and healthy volunteers. In humans, single administration of efgartigimod reduced IgG levels up to 50% whilst multiple dosing further lowered IgGs on average by 75% of baseline levels. Approximately 8 weeks following the last administration, IgG levels returned to baseline. Efgartigimod did not alter the homeostasis of albumin or immunoglobulins other than IgG and no serious adverse events related to efgartigimod infusion were observed. CONCLUSION. Antagonizing FcRn using efgartigimod is safe and results in a specific, profound, and sustained reduction of serum IgG levels. These results warrant further evaluation of this therapeutic approach in IgG-driven autoimmune diseases. TRIAL REGISTRATION. Clinicaltrials.gov NCT03457649. FUNDING. argenx bvba.
Peter Ulrichts, Antonio Guglietta, Torsten Dreier, Tonke van Bragt, Valérie Hanssens, Erik Hofman, Bernhardt Vankerckhoven, Peter Verheesen, Nicolas Ongenae, Valentina Lykhopiy, F. Javier Enriquez, JunHaeng Cho, Raimund J. Ober, E. Sally Ward, Hans de Haard, Nicolas Leupin
JAK2-V617F-positive chronic myeloproliferative neoplasia (CMN) is marked by dysfunction of integrins and adhesion molecules expressed on platelets, erythrocytes and leukocytes. However, the mechanism by which the two major leukocyte integrin chains, β1 and β2, mediate CMN pathophysiology remained unclear. β1 (α4β1; VLA-4) and β2 (αLβ2; LFA-1) integrins are essential regulators for attachment of leukocytes to endothelial cells. We here show enhanced adhesion of granulocytes from JAK2+/VF knock-in mice to vascular cell adhesion molecule 1 (VCAM1) and intercellular adhesion molecule 1 (ICAM1) coated surfaces. Soluble VCAM1 and ICAM1 ligand binding assays revealed increased affinity of β1 and β2 integrins for their respective ligands. For β1 integrins, this correlated with a structural change from the low to the high affinity conformation induced by JAK2-V617F. JAK2-V617F triggers constitutive activation of the integrin inside-out signaling molecule Rap1 resulting in translocation towards the cell membrane. Employing a venous thrombosis model, we demonstrate that neutralizing anti-VLA4 and anti-β2 integrin antibodies suppress pathologic thrombosis as observed in JAK2+/VF mice. In addition, aberrant homing of JAK2+/VF leukocytes to the spleen is inhibited by neutralizing anti-β2 antibodies and by pharmacologic inhibition of Rap1. Thus, our findings identify a cross talk between JAK2-V617F and integrin activation promoting pathologic thrombosis and abnormal trafficking of leukocytes to the spleen. .
Bärbel Edelmann, Nibedita Gupta, Tina M. Schnöder, Anja M. Oelschlegel, Khurrum Shahzad, Jürgen Goldschmidt, Lars Philipsen, Sönke Weinert, Aniket Ghosh, Felix C. Saalfeld, Subbaiah Chary Nimmagadda, Peter Müller, Rüdiger C. Braun-Dullaeus, Juliane Mohr, Denise Wolleschak, Stefanie Kliche, Holger Amthauer, Florian H. Heidel, Burkhart Schraven, Berend Isermann, Andreas Müller, Thomas Fischer
Oxidative stress is an underlying component of acute and chronic kidney disease. Apoptosis signal-regulating kinase 1 (ASK1) is a widely expressed redox-sensitive serine threonine kinase that activates p38 and c-Jun N-terminal kinase (JNK) mitogen-activated protein kinase kinases, and induces apoptotic, inflammatory, and fibrotic signaling in settings of oxidative stress. Herein, we describe the discovery and characterization of a potent and selective small molecule inhibitor of ASK1, GS-444217, and demonstrate the therapeutic potential of ASK1 inhibition to reduce kidney injury and fibrosis. Activation of the ASK1 pathway in glomerular and tubular compartments was confirmed in renal biopsies from patients with diabetic kidney disease (DKD) and was decreased by GS-444217 in several rodent models of kidney injury and fibrosis that collectively represented the hallmarks of DKD pathology. Treatment with GS-444217 reduced progressive inflammation and fibrosis in the kidney and halted decline of glomerular filtration rate. Combination of GS-444217 with enalapril, an angiotensin-converting enzyme inhibitor, led to a greater reduction in proteinuria and regression of glomerulosclerosis. These results identify ASK1 as an important target for renal disease and support the clinical development of an ASK1 inhibitor for the treatment of diabetic kidney disease.
John T. Liles, Britton K. Corkey, Gregory T. Notte, Grant Budas, Eric B. Lansdon, Ford Hinojosa-Kirschenbaum, Shawn S. Badal, Michael Lee, Brian E. Schultz, Sarah Wise, Swetha Pendem, Michael Graupe, Laurie Castonguay, Keith A. Koch, Melanie H. Wong, Giuseppe A. Papalia, Dorothy M. French, Theodore Sullivan, Erik G. Huntzicker, Frank Y. Ma, David J. Nikolic-Paterson, Tareq Altuhaifi, Haichun Yang, Agnes B. Fogo, David G. Breckenridge