Tian et al. report longitudinal and cross-sectional neuroimaging changes in patients recovered from COVID-19 over a 10-month period.
Commensal microbes critically regulate skeletal homeostasis, yet the impact of specific microbiota communities on osteoimmune response mechanisms is unknown. To discern osteoimmunomodulatory effects imparted by the commensal oral microbiota that are distinct from the systemic microbiota, osteoimmunology studies were performed in both alveolar bone and nonoral skeletal sites of specific pathogen–free (SPF) versus germ-free (GF) mice and SPF mice subjected to saline versus chlorhexidine oral rinses. SPF versus GF mice had reduced cortical/trabecular bone and an enhanced pro-osteoclastic phenotype in alveolar bone. TLR signaling and Th17 cells that have known pro-osteoclastic actions were increased in alveolar BM, but not long BM, of SPF versus GF mice. MHC II antigen presentation genes and activated DCs and CD4+ T cells were elevated in alveolar BM, but not long BM, of SPF versus GF mice. These findings were substantiated by in vitro allostimulation studies demonstrating increased activated DCs derived from alveolar BM, but not long BM, of SPF versus GF mice. Chlorhexidine antiseptic rinse depleted the oral, but not gut, bacteriome in SPF mice. Findings from saline- versus chlorhexidine-treated SPF mice corroborated outcomes from SPF versus GF mice, which reveals that the commensal oral microbiota imparts osteoimmunomodulatory effects separate from the systemic microbiome.
Jessica D. Hathaway-Schrader, Johannes D. Aartun, Nicole A. Poulides, Megan B. Kuhn, Blakely E. McCormick, Michael E. Chew, Emily Huang, Richard P. Darveau, Caroline Westwater, Chad M. Novince
The G protein–coupled CXC chemokine receptor 4 (CXCR4) is a candidate therapeutic target for tissue fibrosis. A fully human single-domain antibody-like scaffold i-body AD-114-PA600 (AD-114) with specific high binding affinity to CXCR4 has been developed. To define its renoprotective role, AD-114 was administrated in a mouse model of renal fibrosis induced by folic acid (FA). Increased extracellular matrix (ECM) accumulation, macrophage infiltration, inflammatory response, TGF-β1 expression, and fibroblast activation were observed in kidneys of mice with FA-induced nephropathy. These markers were normalized or partially reversed by AD-114 treatment. In vitro studies demonstrated AD-114 blocked TGF-β1–induced upregulated expression of ECM, matrix metalloproteinase-2, and downstream p38 mitogen-activated protein kinase (p38 MAPK) and PI3K/AKT/mTOR signaling pathways in a renal proximal tubular cell line. Additionally, these renoprotective effects were validated in a second model of unilateral ureteral obstruction using a second generation of AD-114 (Fc-fused AD-114, also named AD-214). Collectively, these results suggest a renoprotective role of AD-114 as it inhibited the chemotactic function of CXCR4 as well as blocked CXCR4 downstream p38 MAPK and PI3K/AKT/mTOR signaling, which establish a therapeutic strategy for AD-114 targeting CXCR4 to limit renal fibrosis.
Qinghua Cao, Chunling Huang, Hao Yi, Anthony J. Gill, Angela Chou, Michael Foley, Chris G. Hosking, Kevin K. Lim, Cristina F. Triffon, Ying Shi, Xin-Ming Chen, Carol A. Pollock
Fibrotic diseases account for nearly half of all deaths in the developed world. Despite its importance, the pathogenesis of fibrosis remains poorly understood. Recently, the two mechanosensitive transcription cofactors YAP and TAZ have emerged as important profibrotic regulators in multiple murine tissues. Despite this growing recognition, a number of important questions remain unanswered, including which cell types require YAP/TAZ activation for fibrosis to occur and the time course of this activation. Here, we present a detailed analysis of the role that myofibroblast YAP and TAZ play in organ fibrosis and the kinetics of their activation. Using analyses of cells, as well as multiple murine and human tissues, we demonstrated that myofibroblast YAP and TAZ were activated early after organ injury and that this activation was sustained. We further demonstrated the critical importance of myofibroblast YAP/TAZ in driving progressive scarring in the kidney, lung, and liver, using multiple transgenic models in which YAP and TAZ were either deleted or hyperactivated. Taken together, these data establish the importance of early injury-induced myofibroblast YAP and TAZ activation as a key event driving fibrosis in multiple organs. This information should help guide the development of new antifibrotic YAP/TAZ inhibition strategies.
Xiaolin He, Monica F. Tolosa, Tianzhou Zhang, Santosh Kumar Goru, Luisa Ulloa Severino, Paraish S. Misra, Caitríona M. McEvoy, Lauren Caldwell, Stephen G. Szeto, Feng Gao, Xiaolan Chen, Cassandra Atin, Victoria Ki, Noah Vukosa, Catherine Hu, Johnny Zhang, Christopher Yip, Adriana Krizova, Jeffrey L. Wrana, Darren A. Yuen
Defective primary cilia cause a range of diseases called ciliopathies, which include hearing loss (HL). Variants in the human oxysterol-binding protein like 2 (OSBPL2/ORP2) are responsible for autosomal dominant nonsyndromic HL (DFNA67). However, the pathogenesis of OSBPL2 deficiency has not been fully elucidated. In this study, we show that the Osbpl2-KO mice exhibited progressive HL and abnormal cochlear development with defective cilia. Further research revealed that OSBPL2 was located at the base of the kinocilia in hair cells (HCs) and primary cilia in supporting cells (SCs) and functioned in the maintenance of ciliogenesis by regulating the homeostasis of PI(4,5)P2 (phosphatidylinositol 4,5-bisphosphate) on the cilia membrane. OSBPL2 deficiency led to a significant increase of PI(4,5)P2 on the cilia membrane, which could be partially rescued by the overexpression of INPP5E. In addition, smoothened and GL13, the key molecules in the Sonic Hedgehog (Shh) signaling pathway, were detected to be downregulated in Osbpl2-KO HEI-OC1 cells. Our findings revealed that OSBPL2 deficiency resulted in ciliary defects and abnormal Shh signaling transduction in auditory cells, which helped to elucidate the underlying mechanism of OSBPL2 deficiency in HL.
Hairong Shi, Hongshun Wang, Cheng Zhang, Yajie Lu, Jun Yao, Zhibin Chen, Guangqian Xing, Qinjun Wei, Xin Cao
Mitophagy and mitochondrial integrated stress response (ISR) are 2 primary protective mechanisms to maintain functional mitochondria. Whether these 2 processes are coordinately regulated remains unclear. Here we show that mitochondrial fission 1 protein (Fis1), which is required for completion of mitophagy, serves as a signaling hub linking mitophagy and ISR. In mouse hepatocytes, high fat diet (HFD) feeding induces unresolved oxidative stress, defective mitophagy and enhanced type I interferon (IFN-I) response implicated in promoting metabolic inflammation. Adenoviral-mediated acute hepatic Fis1 overexpression is sufficient to reduce oxidative damage and improve glucose homeostasis in HFD-fed mice. RNA-Seq analysis reveals that Fis1 triggers a retrograde mitochondria-to-nucleus communication upregulating ISR genes encoding anti-oxidant defense, redox homeostasis, and proteostasis pathways. Fis1-mediated ISR also suppresses expression of IFN-I–stimulated genes through activating transcription factor 5 (Atf5), which inhibits the transactivation activity of interferon regulatory factor 3 (Irf3) known to control IFN-I production. Metabolite analysis demonstrates that Fis1 activation leads to accumulation of fumarate, a TCA cycle intermediate capable of increasing Atf5 activity. Consequently, hepatic Atf5 overexpression or monomethyl fumarate (MMF) treatment improves glucose homeostasis in HFD-fed mice. Collectively, these results support the potential use of small molecules targeting the Fis1-Atf5 axis, such as MMF, to treat metabolic diseases.
Yae-Huei Liou, Jean Personnaz, David Jacobi, Nelson H. Knudsen, Mayer M. Chalom, Kyle A. Starost, Israel C. Nnah, Chih-Hao Lee
The intensity and longevity of inflammatory responses to inhaled allergens is determined largely by the balance between effector and regulatory immune responses, but the mechanisms that determine the relative magnitudes of these opposing forces remain poorly understood. We have found that the type of adjuvant used during allergic sensitization has a profound effect on both the nature and longevity of the pulmonary inflammation triggered by subsequent reexposure to that same provoking allergen. TLR ligand adjuvants and house dust extracts primed immune responses characterized by a mixed neutrophilic and eosinophilic inflammation that was suppressed by multiple daily allergen challenges. During TLR ligand–mediated allergic sensitization, mice displayed transient airway neutrophilia, which triggered the release of TGF-β into the airway. This neutrophil-dependent production of TGF-β during sensitization had a delayed, suppressive effect on eosinophilic responses to subsequent allergen challenge. Neutrophil depletion during sensitization did not affect numbers of Foxp3+ Tregs but increased proportions of Gata3+CD4+ T cells, which, upon their transfer to recipient mice, triggered stronger eosinophilic inflammation. Thus, a neutrophil/TGF-β axis acts during TLR-mediated allergic sensitization to fine-tune the phenotype of developing allergen-specific CD4+ T cells and limit their pathogenicity, suggesting a novel immunotherapeutic approach to control eosinophilia in asthma.
Gregory S. Whitehead, Seddon Y. Thomas, Keiko Nakano, Derek J. Royer, Catherine G. Burke, Hideki Nakano, Donald N. Cook
Aristolochic acid (AA) is the causative nephrotoxic alkaloid in AA nephropathy, which results in a tubulointerstitial fibrosis. AA causes direct proximal tubule damage as well as an influx of macrophages, although the role of macrophages in pathogenesis is poorly understood. Here, we demonstrate that AA directly stimulates migration, inflammation, and ROS production in macrophages ex vivo. Cells lacking interferon regulatory factor 4 (IRF4), a known regulator of macrophage migration and phenotype, had a reduced migratory response, though effects on ROS production and inflammation were preserved or increased relative to WT cells. Macrophage-specific IRF4-knockout mice were protected from both acute and chronic kidney effects of AA administration based on functional and histological analysis. Renal macrophages from kidneys of AA-treated macrophage-specific IRF4-knockout mice demonstrated increased apoptosis and ROS production compared with WT controls, indicating that AA directly polarizes macrophages to a promigratory and proinflammatory phenotype. However, knockout mice had reduced renal macrophage abundance following AA administration. While macrophages lacking IRF4 can adopt a proinflammatory phenotype upon AA exposure, their inability to migrate to the kidney and increased rates of apoptosis upon infiltration provide protection from AA in vivo. These results provide evidence of direct AA effects on macrophages in AA nephropathy and add to the growing body of evidence that supports a key role of IRF4 in modulating macrophage function in kidney injury.
Kensuke Sasaki, Andrew S. Terker, Jiaqi Tang, Shirong Cao, Juan Pablo Arroyo, Aolei Niu, Suwan Wang, Xiaofeng Fan, Yahua Zhang, Stephanie R. Bennett, Ming-zhi Zhang, Raymond C. Harris
Sustained proliferative signaling and resisting cell death are hallmarks of cancer. Zinc finger protein 277 (ZNF277; murine Zfp277), a transcription factor regulating cellular senescence, is overexpressed in colon cancer, but its actions in intestinal homeostasis and neoplasia are unclear. Using human and murine intestine, human colon cancer cells, and ApcMin/+ mice with dysregulated β-catenin signaling and exuberant intestinal neoplasia, we explored the actions of ZNF277/Zfp277 and defined the underlying mechanisms. In normal human and murine intestine, ZNF277/Zfp277 was expressed uniquely in early stem cell progenitors, undifferentiated transit-amplifying cells (TACs). Zfp277 was overexpressed in the ApcMin/+ mouse colon, implicating ZNF277/Zfp277 as a transcriptional target of β-catenin signaling. We confirmed this by showing β-catenin knockdown reduced ZNF277 expression and, using chromatin IP, identified 2 β-catenin binding sites in the ZNF277 promoter. Zfp277 deficiency attenuated intestinal epithelial cell proliferation and tumor formation, and it strikingly prolonged ApcMin/+ mouse survival. RNA-Seq and PCR analyses revealed that Zfp277 modulates expression of genes in key cancer pathways, including β-catenin signaling, the HOXD family that regulates development, and p21WAF1, a cell cycle inhibitor and tumor suppressor. In both human colon cancer cells and the murine colon, ZNF277/Zfp277 deficiency induced p21WAF1 expression and promoted senescence. Our findings identify ZNF277/Zfp277 as both a TAC marker and colon cancer oncogene that regulates cellular proliferation and senescence, in part by repressing p21WAF1 expression.
Guofeng Xie, Zhongsheng Peng, Jinqing Liang, Shannon M. Larabee, Cinthia B. Drachenberg, Harris Yfantis, Jean-Pierre Raufman
Monocyte-derived macrophages (MDMs) are key players in tissue homeostasis and diseases regulated by a variety of signaling molecules. Recent literature has highlighted the ability for biogenic amines to regulate macrophage functions, but the mechanisms governing biogenic amine signaling in and around immune cells remain nebulous. In the CNS, biogenic amine transporters are regarded as the master regulators of neurotransmitter signaling. While we and others have shown that macrophages express these transporters, relatively little is known of their function in these cells. To address these knowledge gaps, we investigated the function of norepinephrine transporter (NET) and dopamine transporter (DAT) on human MDMs. We found that both NET and DAT are present and can uptake substrate from the extracellular space at baseline. Not only was DAT expressed in cultured MDMs, but it was also detected in a subset of intestinal macrophages in situ. Surprisingly, we discovered a NET-independent, DAT-mediated immunomodulatory mechanism in response to LPS. LPS induced reverse transport of dopamine through DAT, engaging an autocrine/paracrine signaling loop that regulated the macrophage response. Removing this signaling loop enhanced the proinflammatory response to LPS. Our data introduce a potential role for DAT in the regulation of innate immunity.
Phillip M. Mackie, Adithya Gopinath, Dominic M. Montas, Alyssa Nielsen, Aidan Smith, Rachel A. Nolan, Kaitlyn Runner, Stephanie M. Matt, John McNamee, Joshua E. Riklan, Kengo Adachi, Andria Doty, Adolfo Ramirez-Zamora, Long Yan, Peter J. Gaskill, Wolfgang J. Streit, Michael S. Okun, Habibeh Khoshbouei
Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal disease characterized by collagen deposition within the lung interstitium. Bacterial infection is associated with increased morbidity and more rapid mortality in IPF patient populations, and pathogens such as methicillin-resistant Staphylococcus aureus (MRSA) are commonly isolated from the lungs of hospitalized patients with IPF. Despite this, the effects of fibrotic lung injury on critical immune responses to infection remain unknown. In the present study, we show that, like humans with IPF, fibrotic mice infected with MRSA exhibit increased morbidity and mortality compared with uninfected fibrotic mice. We determine that fibrosis conferred a defect in MRSA clearance compared with nonfibrotic mice, resulting from blunted innate immune responses. We show that fibrosis inhibited neutrophil intracellular killing of MRSA through impaired neutrophil elastase release and oxidative radical production. Additionally, we demonstrate that lung macrophages from fibrotic mice have impaired phagocytosis of MRSA. Our study describes potentially novel impairments of antimicrobial responses upon pulmonary fibrosis development, and our findings suggest a possible mechanism for why patients with IPF are at greater risk of morbidity and mortality related to infection.
Helen I. Warheit-Niemi, Summer J. Edwards, Shuvasree SenGupta, Carole A. Parent, Xiaofeng Zhou, David N. O’Dwyer, Bethany B. Moore
Type 1 diabetes is an autoimmune disease characterized by insulin-producing β cell destruction. Although islet transplantation restores euglycemia and improves patient outcomes, an ideal transplant site remains elusive. Brown adipose tissue (BAT) has a highly vascularized and antiinflammatory microenvironment. Because these tissue features can promote islet graft survival, we hypothesized that islets transplanted into BAT will maintain islet graft and BAT function while delaying immune-mediated rejection. We transplanted syngeneic and allogeneic islets into BAT or under the kidney capsule of streptozotocin-induced diabetic NOD.Rag and NOD mice to investigate islet graft function, BAT function, metabolism, and immune-mediated rejection. Islet grafts within BAT restored euglycemia similarly to kidney capsule controls. Islets transplanted in BAT maintained expression of islet hormones and transcription factors and were vascularized. Compared with those in kidney capsule and euglycemic mock-surgery controls, no differences in glucose or insulin tolerance, thermogenic regulation, or energy expenditure were observed with islet grafts in BAT. Immune profiling of BAT revealed enriched antiinflammatory macrophages and T cells. Compared with the kidney capsule control, there were significant delays in autoimmune and allograft rejection of islets transplanted in BAT, possibly due to increased antiinflammatory immune populations. Our data support BAT as an alternative islet transplant site that may improve graft survival.
Jessica D. Kepple, Jessie M. Barra, Martin E. Young, Chad S. Hunter, Hubert M. Tse
Impaired glucose metabolism is observed in obesity and type 2 diabetes. Glucose controls gene expression through the transcription factor ChREBP in liver and adipose tissues. Mlxipl encodes 2 isoforms: ChREBPα, the full-length form (translocation into the nucleus is under the control of glucose), and ChREBPβ, a constitutively nuclear shorter form. ChREBPβ gene expression in white adipose tissue is strongly associated with insulin sensitivity. Here, we investigated the consequences of ChREBPβ deficiency on insulin action and energy balance. ChREBPβ-deficient male and female C57BL6/J and FVB/N mice were produced using CRISPR/Cas9-mediated gene editing. Unlike global ChREBP deficiency, lack of ChREBPβ showed modest effects on gene expression in adipose tissues and the liver, with variations chiefly observed in brown adipose tissue. In mice fed chow and 2 types of high-fat diets, lack of ChREBPβ had moderate effects on body composition and insulin sensitivity. At thermoneutrality, ChREBPβ deficiency did not prevent the whitening of brown adipose tissue previously reported in total ChREBP-KO mice. These findings revealed that ChREBPβ is dispensable for metabolic adaptations to nutritional and thermic challenges.
Emeline Recazens, Geneviève Tavernier, Jérémy Dufau, Camille Bergoglio, Fadila Benhamed, Stéphanie Cassant-Sourdy, Marie-Adeline Marques, Sylvie Caspar-Bauguil, Alice Brion, Laurent Monbrun, Renaud Dentin, Clara Ferrier, Mélanie Leroux, Pierre-Damien Denechaud, Cedric Moro, Jean-Paul Concordet, Catherine Postic, Etienne Mouisel, Dominique Langin
Chronic obstructive pulmonary disease (COPD) is a debilitating chronic disease and the third-leading cause of mortality worldwide. It is characterized by airway neutrophilia, promoting tissue injury through release of toxic mediators and proteases. Recently, it has been shown that neutrophil-derived extracellular vesicles (EVs) from lungs of patients with COPD can cause a neutrophil elastase–dependent (NE-dependent) COPD-like disease upon transfer to mouse airways. However, in vivo preclinical models elucidating the impact of EVs on disease are lacking, delaying opportunities for therapeutic testing. Here, we developed an in vivo preclinical mouse model of lung EV–induced COPD. EVs from in vivo LPS-activated mouse neutrophils induced COPD-like disease in naive recipients through an α-1 antitrypsin–resistant, NE-dependent mechanism. Together, these results show a key pathogenic and mechanistic role for neutrophil-derived EVs in a mouse model of COPD. Broadly, the in vivo model described herein could be leveraged to develop targeted therapies for severe lung disease.
Camilla Margaroli, Matthew C. Madison, Liliana Viera, Derek W. Russell, Amit Gaggar, Kristopher R. Genschmer, J. Edwin Blalock
Lung alveolar type 2 (AT2) cells are progenitors for alveolar type 1 (AT1) cells. Although many factors regulate AT2 cell plasticity, the role of mitochondrial calcium (mCa2+) uptake in controlling AT2 cells remains unclear. We previously identified that the miR-302 family supports lung epithelial progenitor cell proliferation and less differentiated phenotypes during development. Here, we report that a sustained elevation of miR-302 in adult AT2 cells decreases AT2-to-AT1 cell differentiation during the Streptococcus pneumoniae–induced lung injury repair. We identified that miR-302 targets and represses the expression of mitochondrial Ca2+ uptake 1 (MICU1), which regulates mCa2+ uptake through the mCa2+ uniporter channel by acting as a gatekeeper at low cytosolic Ca2+ levels. Our results reveal a marked increase in MICU1 protein expression and decreased mCa2+ uptake during AT2-to-AT1 cell differentiation in the adult lung. Deletion of Micu1 in AT2 cells reduces AT2-to-AT1 cell differentiation during steady-state tissue maintenance and alveolar epithelial regeneration after bacterial pneumonia. These studies indicate that mCa2+ uptake is extensively modulated during AT2-to-AT1 cell differentiation and that MICU1-dependent mCa2+ uniporter channel gating is a prominent mechanism modulating AT2-to-AT1 cell differentiation.
Mir Ali, Xiaoying Zhang, Ryan LaCanna, Dhanendra Tomar, John W. Elrod, Ying Tian
Mammalian skeletal muscle contains heterogenous myofibers with different contractile and metabolic properties that sustain muscle mass and endurance capacity. The transcriptional regulators that govern these myofiber gene programs have been elucidated. However, the hormonal cues that direct the specification of myofiber types and muscle endurance remain largely unknown. Here, we uncover the secreted factor Tsukushi (TSK) as an extracellular signal that is required for maintaining muscle mass, strength, and endurance capacity and that contributes to muscle regeneration. Mice lacking TSK exhibited reduced grip strength and impaired exercise capacity. Muscle transcriptomic analysis revealed that TSK deficiency results in a remarkably selective impairment in the expression of myofibrillar genes, characteristic of slow-twitch muscle fibers, that is associated with abnormal neuromuscular junction formation. AAV-mediated overexpression of TSK failed to rescue these myofiber defects in adult mice, suggesting that the effects of TSK on myofibers are likely restricted to certain developmental stages. Finally, mice lacking TSK exhibited diminished muscle regeneration following cardiotoxin-induced muscle injury. These findings support a crucial role of TSK as a hormonal cue in the regulation of contractile gene expression, endurance capacity, and muscle regeneration.
Qiuyu Wang, Xiaoxue Qiu, Tongyu Liu, Cheehoon Ahn, Jeffrey F. Horowitz, Jiandie D. Lin
Why multisystem inflammatory syndrome in children (MIS-C) develops after SARS-CoV-2 infection in a subset of children is unknown. We hypothesized that aberrant virus–specific T cell responses contribute to MIS-C pathogenesis. We quantified SARS-CoV-2–reactive T cells, serologic responses against major viral proteins, and cytokine responses from plasma and peripheral blood mononuclear cells in children with convalescent COVID-19, in children with acute MIS-C, and in healthy controls. Children with MIS-C had significantly lower virus-specific CD4+ and CD8+ T cell responses to major SARS-CoV-2 antigens compared with children convalescing from COVID-19. Furthermore, T cell responses in participants with MIS-C were similar to or lower than those in healthy controls. Serologic responses against spike receptor binding domain (RBD), full-length spike, and nucleocapsid were similar among convalescent COVID-19 and MIS-C, suggesting functional B cell responses. Cytokine profiling demonstrated predominant Th1 polarization of CD4+ T cells from children with convalescent COVID-19 and MIS-C, although cytokine production was reduced in MIS-C. Our findings support a role for constrained induction of anti–SARS-CoV-2–specific T cells in the pathogenesis of MIS-C.
Vidisha Singh, Veronica Obregon-Perko, Stacey A. Lapp, Anna Marie Horner, Alyssa Brooks, Lisa Macoy, Laila Hussaini, Austin Lu, Theda Gibson, Guido Silvestri, Alba Grifoni, Daniela Weiskopf, Alessandro Sette, Evan J. Anderson, Christina A. Rostad, Ann Chahroudi
BACKGROUND Prostate cancer is multifocal with distinct molecular subtypes. The utility of genomic subtyping has been challenged due to inter- and intrafocal heterogeneity. We sought to characterize the subtype-defining molecular alterations of primary prostate cancer across all tumor foci within radical prostatectomy (RP) specimens and determine the prevalence of collision tumors.METHODS From the Early Detection Research Network cohort, we identified 333 prospectively collected RPs from 2010 to 2014 and assessed ETS-related gene (ERG), serine peptidase inhibitor Kazal type 1 (SPINK1), phosphatase and tensin homolog (PTEN), and speckle type BTB/POZ protein (SPOP) molecular status. We utilized dual ERG/SPINK1 immunohistochemistry and fluorescence in situ hybridization to confirm ERG rearrangements and characterize PTEN deletion, as well as high-resolution melting curve analysis and Sanger sequencing to determine SPOP mutation status.RESULTS Based on index focus alone, ERG, SPINK1, PTEN, and SPOP alterations were identified in 47.5%, 10.8%, 14.3%, and 5.1% of RP specimens, respectively. In 233 multifocal RPs with ERG/SPINK1 status in all foci, 139 (59.7%) had discordant molecular alterations between foci. Collision tumors, as defined by discrepant ERG/SPINK1 status within a single focus, were identified in 29 (9.4%) RP specimens.CONCLUSION Interfocal molecular heterogeneity was identified in about 60% of multifocal RP specimens, and collision tumors were present in about 10%. We present this phenomenon as a model for the intrafocal heterogeneity observed in previous studies and propose that future genomic studies screen for collision tumors to better characterize molecular heterogeneity.FUNDING Early Detection Research Network US National Cancer Institute (NCI) 5U01 CA111275-09, Center for Translational Pathology at Weill Cornell Medicine (WCM) Department of Pathology and Laboratory Medicine, US NCI (WCM SPORE in Prostate Cancer, P50CA211024-01), R37CA215040, Damon Runyon Cancer Research Foundation, US MetLife Foundation Family Clinical Investigator Award, Norwegian Cancer Society (grant 208197), and South-Eastern Norway Regional Health Authority (grant 2019016 and 2020063).
Jacqueline Fontugne, Peter Y. Cai, Hussein Alnajar, Bhavneet Bhinder, Kyung Park, Huihui Ye, Shaham Beg, Verena Sailer, Javed Siddiqui, Mirjam Blattner-Johnson, Jaclyn A. Croyle, Zohal Noorzad, Carla Calagua, Theresa Y. MacDonald, Ulrika Axcrona, Mari Bogaard, Karol Axcrona, Douglas S. Scherr, Martin G. Sanda, Bjarne Johannessen, Arul M. Chinnaiyan, Olivier Elemento, Rolf I. Skotheim, Mark A. Rubin, Christopher E. Barbieri, Juan Miguel Mosquera
Recent research on altering threat memory has focused on a reconsolidation window. During reconsolidation, threat memories are retrieved and become labile. Reconsolidation of distinct threat memories is synapse dependent, whereas the underlying regulatory mechanism of the specificity of reconsolidation is poorly understood. We designed a unique behavioral paradigm in which a distinct threat memory can be retrieved through the associated conditioned stimulus. In addition, we proposed a regulatory mechanism by which the activation of acid-sensing ion channels (ASICs) strengthens the distinct memory trace associated with the memory reconsolidation to determine its specificity. The activation of ASICs by CO2 inhalation, when paired with memory retrieval, triggers the reactivation of the distinct memory trace, resulting in greater memory lability. ASICs potentiate the memory trace by altering the amygdala-dependent synaptic transmission and plasticity at selectively targeted synapses. Our results suggest that inhaling CO2 during the retrieval event increases the lability of a threat memory through a synapse-specific reconsolidation process.
Erin E. Koffman, Charles M. Kruse, Kritika Singh, Farzaneh Sadat Naghavi, Melissa A. Curtis, Jennifer Egbo, Mark Houdi, Boren Lin, Hui Lu, Jacek Debiec, Jianyang Du
Myocardial infarction causes pathological changes in the autonomic nervous system, which exacerbate heart failure and predispose to fatal ventricular arrhythmias and sudden death. These changes are characterized by sympathetic activation and parasympathetic dysfunction (reduced vagal tone). Reasons for the central vagal withdrawal and, specifically, whether myocardial infarction causes changes in cardiac vagal afferent neurotransmission that then affect efferent tone, remain unknown. The objective of this study was to evaluate whether myocardial infarction causes changes in vagal neuronal afferent signaling. Using in vivo neural recordings from the inferior vagal (nodose) ganglia and immunohistochemical analyses, structural and functional alterations in vagal sensory neurons were characterized in a chronic porcine infarct model and compared with normal animals. Myocardial infarction caused an increase in the number of nociceptive neurons but a paradoxical decrease in functional nociceptive signaling. No changes in mechanosensitive neurons were observed. Notably, nociceptive neurons demonstrated an increase in GABAergic expression. Given that nociceptive signaling through the vagal ganglia increases efferent vagal tone, the results of this study suggest that a decrease in functional nociception, possibly due to an increase in expression of inhibitory neurotransmitters, may contribute to vagal withdrawal after myocardial infarction.
Siamak Salavatian, Jonathan D. Hoang, Naoko Yamaguchi, Zulfiqar Ali Lokhandwala, Mohammed Amer Swid, John Andrew Armour, Jeffrey L. Ardell, Marmar Vaseghi
BACKGROUND After the initial surge in COVID-19 cases, large numbers of patients were discharged from a hospital without assessment of recovery. Now, an increasing number of patients report postacute neurological sequelae, known as “long COVID” — even those without specific neurological manifestations in the acute phase.METHODS Dynamic brain changes are crucial for a better understanding and early prevention of “long COVID.” Here, we explored the cross-sectional and longitudinal consequences of COVID-19 on the brain in 34 discharged patients without neurological manifestations. Gray matter morphology, cerebral blood flow (CBF), and volumes of white matter tracts were investigated using advanced magnetic resonance imaging techniques to explore dynamic brain changes from 3 to 10 months after discharge.RESULTS Overall, the differences of cortical thickness were dynamic and finally returned to the baseline. For cortical CBF, hypoperfusion in severe cases observed at 3 months tended to recover at 10 months. Subcortical nuclei and white matter differences between groups and within subjects showed various trends, including recoverable and long-term unrecovered differences. After a 10-month recovery period, a reduced volume of nuclei in severe cases was still more extensive and profound than that in mild cases.CONCLUSION Our study provides objective neuroimaging evidence for the coexistence of recoverable and long-term unrecovered changes in 10-month effects of COVID-19 on the brain. The remaining potential abnormalities still deserve public attention, which is critically important for a better understanding of “long COVID” and early clinical guidance toward complete recovery.FUNDING National Natural Science Foundation of China.
Tian Tian, Jinfeng Wu, Tao Chen, Jia Li, Su Yan, Yiran Zhou, Xiaolong Peng, Yuanhao Li, Ning Zheng, Aoling Cai, Qin Ning, Hongbing Xiang, Fuqiang Xu, Yuanyuan Qin, Wenzhen Zhu, Jie Wang
Peroxisomes are specialized cellular organelles involved in a variety of metabolic processes. In humans, mutations leading to complete loss of peroxisomes cause multiorgan failure (Zellweger’s spectrum disorders, ZSD), including renal impairment. However, the (patho)physiological role of peroxisomes in the kidney remains unknown. We addressed the role of peroxisomes in renal function in mice with conditional ablation of peroxisomal biogenesis in the renal tubule (cKO mice). Functional analyses did not reveal any overt kidney phenotype in cKO mice. However, infant male cKO mice had lower body and kidney weights, and adult male cKO mice exhibited substantial reductions in kidney weight and kidney weight/body weight ratio. Stereological analysis showed an increase in mitochondria density in proximal tubule cells of cKO mice. Integrated transcriptome and metabolome analyses revealed profound reprogramming of a number of metabolic pathways, including metabolism of glutathione and biosynthesis/biotransformation of several major classes of lipids. Although this analysis suggested compensated oxidative stress, challenge with high-fat feeding did not induce significant renal impairments in cKO mice. We demonstrate that renal tubular peroxisomes are dispensable for normal renal function. Our data also suggest that renal impairments in patients with ZSD are of extrarenal origin.
Camille Ansermet, Gabriel Centeno, Sylvain Pradervand, Dusan Harmacek, Andy Garcia, Jean Daraspe, Sai Kocherlakota, Myriam Baes, Yohan Bignon, Dmitri Firsov
BACKGROUND Most individuals with prior COVID-19 disease manifest long-term protective immune responses against reinfection. Accordingly, we tested the hypothesis that humoral immune and reactogenicity responses to a SARS-CoV-2 mRNA vaccine differ in individuals with and without prior COVID-19 disease.METHODS Health care workers (n = 61) with (n = 30) and without (n = 31) prior COVID-19 disease received two 30 μg doses of Pfizer BNT162b2 vaccine 3 weeks apart. Serum IgG antibody against the spike receptor-binding domain; serum neutralizing activity; and vaccine reactogenicity were assessed longitudinally every 2 weeks for 56 days after the first injection.RESULTS The COVID-19 group manifested more rapid increases in spike IgG antibody and serum neutralizing activity after the first vaccine dose but showed little or no increase after the second dose compared with the infection-naive group. In fact, spike IgG was at its maximum level after the first dose in 36% of the COVID-19 group versus 0% of the infection-naive group. Peak IgG antibody levels were lower but appeared to fall more slowly in the COVID-19 group versus the infection-naive group. Finally, adverse systemic reactions, e.g., fever, headache, and malaise, were more frequent and lasted longer after both the first and second injection in the COVID-19 group than in the infection-naive group.CONCLUSION Individuals with prior COVID-19 disease demonstrate a robust, accelerated humoral immune response to the first dose but an attenuated response to the second dose of BNT162b2 vaccine compared with controls. The COVID-19 group also experienced greater reactogenicity. Humoral responses and reactogenicity to BNT162b2 differ qualitatively and quantitatively in individuals with prior COVID-19 disease compared with infection-naive individuals.FUNDING This work was supported by Temple University institutional funds.
Steven G. Kelsen, Alan S. Braverman, Mark O. Aksoy, Jacob A. Hayman, Puja S. Patel, Charu Rajput, Huaqing Zhao, Susan G. Fisher, Michael R. Ruggieri Sr., Nina T. Gentile
Total body irradiation (TBI) targets sensitive bone marrow hematopoietic cells and gut epithelial cells, causing their death and inducing a state of immunodeficiency combined with intestinal dysbiosis and nonproductive immune responses. We found enhanced Pseudomonas aeruginosa (PAO1) colonization of the gut leading to host cell death and strikingly decreased survival of irradiated mice. The PAO1-driven pathogenic mechanism includes theft-ferroptosis realized via (a) curbing of the host antiferroptotic system, GSH/GPx4, and (b) employing bacterial 15-lipoxygenase to generate proferroptotic signal — 15-hydroperoxy-arachidonoyl-PE (15-HpETE-PE) — in the intestines of irradiated and PAO1-infected mice. Global redox phospholipidomics of the ileum revealed that lysophospholipids and oxidized phospholipids, particularly oxidized phosphatidylethanolamine (PEox), represented the major factors that contributed to the pathogenic changes induced by total body irradiation and infection by PAO1. A lipoxygenase inhibitor, baicalein, significantly attenuated animal lethality, PAO1 colonization, intestinal epithelial cell death, and generation of ferroptotic PEox signals. Opportunistic PAO1 mechanisms included stimulation of the antiinflammatory lipoxin A4, production and suppression of the proinflammatory hepoxilin A3, and leukotriene B4. Unearthing complex PAO1 pathogenic/virulence mechanisms, including effects on the host anti/proinflammatory responses, lipid metabolism, and ferroptotic cell death, points toward potentially new therapeutic and radiomitigative targets.
Haider H. Dar, Michael W. Epperly, Vladimir A. Tyurin, Andrew A. Amoscato, Tamil S. Anthonymuthu, Austin B. Souryavong, Alexander A. Kapralov, Galina V. Shurin, Svetlana N. Samovich, Claudette M. St. Croix, Simon C. Watkins, Sally E. Wenzel, Rama K. Mallampalli, Joel S. Greenberger, Hülya Bayır, Valerian E. Kagan, Yulia Y. Tyurina
The molecular mechanisms that drive the acquisition of distinct neural crest cell (NCC) fates is still poorly understood. Here, we identified Prdm6 as an epigenetic modifier that temporally and spatially regulates the expression of NCC specifiers and determines the fate of a subset of migrating cardiac NCCs (CNCCs). Using transcriptomic analysis and genetic and fate mapping approaches in transgenic mice, we showed that disruption of Prdm6 was associated with impaired CNCC differentiation, delamination, and migration and led to patent ductus arteriosus (DA) and ventricular noncompaction. Bulk and single-cell RNA-Seq analyses of the DA and CNCCs identified Prdm6 as a regulator of a network of CNCC specification genes, including Wnt1, Tfap2b, and Sox9. Loss of Prdm6 in CNCCs diminished its expression in the pre-epithelial–mesenchymal transition (pre-EMT) cluster, resulting in the retention of NCCs in the dorsal neural tube. This defect was associated with diminished H4K20 monomethylation and G1-S progression and augmented Wnt1 transcript levels in pre-EMT and neural tube clusters, which we showed was the major driver of the impaired CNCC migration. Altogether, these findings revealed Prdm6 as a key regulator of CNCC differentiation and migration and identified Prdm6 and its regulated network as potential targets for the treatment of congenital heart diseases.
Lingjuan Hong, Na Li, Victor Gasque, Sameet Mehta, Lupeng Ye, Yinyu Wu, Jinyu Li, Andreas Gewies, Jürgen Ruland, Karen K. Hirschi, Anne Eichmann, Caroline Hendry, David van Dijk, Arya Mani
Adiponectin receptor 1 (ADIPOR1) is a lipid and glucose metabolism regulator that possesses intrinsic ceramidase activity. Mutations of the ADIPOR1 gene have been associated with nonsyndromic and syndromic retinitis pigmentosa. Here, we show that the absence of AdipoR1 in mice leads to progressive photoreceptor degeneration, significant reduction of electroretinogram amplitudes, decreased retinoid content in the retina, and reduced cone opsin expression. Single-cell RNA-Seq results indicate that ADIPOR1 encoded the most abundantly expressed ceramidase in mice and one of the 2 most highly expressed ceramidases in the human retina, next to acid ceramidase ASAH1. We discovered an accumulation of ceramides in the AdipoR1–/– retina, likely due to insufficient ceramidase activity for healthy retina function, resulting in photoreceptor death. Combined treatment with desipramine/L-cycloserine (DC) lowered ceramide levels and exerted a protective effect on photoreceptors in AdipoR1–/– mice. Moreover, we observed improvement in cone-mediated retinal function in the DC-treated animals. Lastly, we found that prolonged DC treatment corrected the electrical responses of the primary visual cortex to visual stimuli, approaching near-normal levels for some parameters. These results highlight the importance of ADIPOR1 ceramidase in the retina and show that pharmacological inhibition of ceramide generation can provide a therapeutic strategy for ADIPOR1-related retinopathy.
Dominik Lewandowski, Andrzej T. Foik, Roman Smidak, Elliot H. Choi, Jianye Zhang, Thanh Hoang, Aleksander Tworak, Susie Suh, Henri Leinonen, Zhiqian Dong, Antonio F.M. Pinto, Emily Tom, Jennings Luu, Joan Lee, Xiuli Ma, Erhard Bieberich, Seth Blackshaw, Alan Saghatelian, David C. Lyon, Dorota Skowronska-Krawczyk, Marcin Tabaka, Krzysztof Palczewski
Capillary malformation-arteriovenous malformation (CM-AVM) is a blood vascular anomaly caused by inherited loss-of-function mutations in RASA1 or EPHB4 genes, which encode p120 Ras GTPase-activating protein (p120 RasGAP/RASA1) and Ephrin receptor B4 (EPHB4). However, whether RASA1 and EPHB4 function in the same molecular signaling pathway to regulate the blood vasculature is uncertain. Here, we show that induced endothelial cell–specific (EC-specific) disruption of Ephb4 in mice resulted in accumulation of collagen IV in the EC ER, leading to EC apoptotic death and defective developmental, neonatal, and pathological angiogenesis, as reported previously in induced EC-specific RASA1-deficient mice. Moreover, defects in angiogenic responses in EPHB4-deficient mice could be rescued by drugs that inhibit signaling through the Ras pathway and drugs that promote collagen IV export from the ER. However, EPHB4-mutant mice that expressed a form of EPHB4 that is unable to physically engage RASA1 but retains protein tyrosine kinase activity showed normal angiogenic responses. These findings provide strong evidence that RASA1 and EPHB4 function in the same signaling pathway to protect against the development of CM-AVM independent of physical interaction and have important implications for possible means of treatment of this disease.
Di Chen, Elizabeth D. Hughes, Thomas L. Saunders, Jiangping Wu, Magda N. Hernandez Vasquez, Taija Makinen, Philip D. King
BACKGROUND Vaccine-elicited adaptive immunity is a prerequisite for control of SARS-CoV-2 infection. Multiple sclerosis (MS) disease-modifying therapies (DMTs) differentially target humoral and cellular immunity. A comprehensive comparison of the effects of MS DMTs on SARS-CoV-2 vaccine–specific immunity is needed, including quantitative and functional B and T cell responses.METHODS Spike-specific Ab and T cell responses were measured before and following SARS-CoV-2 vaccination in a cohort of 80 study participants, including healthy controls and patients with MS in 6 DMT groups: untreated and treated with glatiramer acetate (GA), dimethyl fumarate (DMF), natalizumab (NTZ), sphingosine-1-phosphate (S1P) receptor modulators, and anti-CD20 mAbs. Anti–spike-Ab responses were assessed by Luminex assay, VirScan, and pseudovirus neutralization. Spike-specific CD4+ and CD8+ T cell responses were characterized by activation-induced marker and cytokine expression and tetramer.RESULTS Anti-spike IgG levels were similar between healthy control participants and patients with untreated MS and those receiving GA, DMF, or NTZ but were reduced in anti-CD20 mAb– and S1P-treated patients. Anti-spike seropositivity in anti-CD20 mAb–treated patients was correlated with CD19+ B cell levels and inversely correlated with cumulative treatment duration. Spike epitope reactivity and pseudovirus neutralization were reduced in anti-CD20 mAb– and S1P-treated patients. Spike-specific CD4+ and CD8+ T cell reactivity remained robust across all groups, except in S1P-treated patients, in whom postvaccine CD4+ T cell responses were attenuated.CONCLUSION These findings from a large cohort of patients with MS exposed to a wide spectrum of MS immunotherapies have important implications for treatment-specific COVID-19 clinical guidelines.FUNDING NIH grants 1K08NS107619, K08NS096117, R01AI159260, R01NS092835, R01AI131624, and R21NS108159; NMSS grants TA-1903-33713 and RG1701-26628; Westridge Foundation; Chan Zuckerberg Biohub; Maisin Foundation.
Joseph J. Sabatino Jr., Kristen Mittl, William M. Rowles, Kira McPolin, Jayant V. Rajan, Matthew T. Laurie, Colin R. Zamecnik, Ravi Dandekar, Bonny D. Alvarenga, Rita P. Loudermilk, Chloe Gerungan, Collin M. Spencer, Sharon A. Sagan, Danillo G. Augusto, Jessa R. Alexander, Joseph L. DeRisi, Jill A. Hollenbach, Michael R. Wilson, Scott S. Zamvil, Riley Bove
Jianqiang Bao, Carlos J. Perez, Jeesun Kim, Huan Zhang, Caitlin J. Murphy, Tewfik Hamidi, Jean Jaubert, Craig D. Platt, Janet Chou, Meichun Deng, Meng-Hua Zhou, Yuying Huang, Héctor Gaitán-Peñas, Jean-Louis Guénet, Kevin Lin, Yue Lu, Taiping Chen, Mark T. Bedford, Sharon Y.R. Dent, John H. Richburg, Raúl Estévez, Hui-Lin Pan, Raif S. Geha, Qinghua Shi, Fernando Benavides