48 total articles
Following injury or infection, the epithelial cells of the alveoli can regenerate, but the source of the new cells and the signals that promote their growth are not completely understood. On page 3025, Barkauskas et al. show that alveolar epithelial type 2 cells (AEC2s) self-renew and differentiate in adult mice, suggesting that they contribute to tissue maintenance. In models of lung injury, AEC2s proliferate and expand, contributing to tissue repair. In this image, an AEC2 cocultured with a specific mesenchymal cell type formed a 3D structure called an alveolosphere, in which the interior cells have differentiated and adopted a mature AEC1 phenotype.
Immunotherapy can be an effective treatment for metastatic cancer, but a significant subpopulation will not respond, likely due to the lack of antigenic mutations or the immune-evasive properties of cancer. Likewise, radiation therapy (RT) is an established cancer treatment, but local failures still occur. Clinical observations suggest that RT may expand the therapeutic reach of immunotherapy. We examine the immunobiologic and clinical rationale for combining RT and immunotherapy, two modalities yet to be used in combination in routine practice. Preclinical data indicate that RT can potentiate the systemic efficacy of immunotherapy, while activation of the innate and adaptive immune system can enhance the local efficacy of RT.
Anusha Kalbasi, Carl H. June, Naomi Haas, Neha Vapiwala
Insulin resistance (IR) and hyperinsulinemia are hallmarks of the metabolic syndrome, as are central adiposity, dyslipidemia, and a predisposition to type 2 diabetes, atherosclerotic cardiovascular disease, hypertension, and certain cancers. Regular exercise and calorie restriction have long been known to increase insulin sensitivity and decrease the prevalence of these disorders. The subsequent identification of AMP-activated protein kinase (AMPK) and its activation by exercise and fuel deprivation have led to studies of the effects of AMPK on both IR and metabolic syndrome–related diseases. In this review, we evaluate this body of literature, with special emphasis on the hypothesis that dysregulation of AMPK is both a pathogenic factor for these disorders in humans and a target for their prevention and therapy.
Neil B. Ruderman, David Carling, Marc Prentki, José M. Cacicedo
Apoptotic cells are rapidly phagocytosed by macrophages, a process that represents a critical step in tissue remodeling, immune responses, and the resolution of inflammation. In 1998, Peter Henson, Donna Bratton, and colleagues at National Jewish Health demonstrated that phagocytosis of apoptotic cells actively suppresses inflammation by inhibiting the production of inflammatory cytokines and inducing production of antiinflammatory factors, including TGF-β and prostaglandin E2. Here they discuss the evolving relationship among apoptosis, phagocytosis, and inflammation.
Peter M. Henson, Donna L. Bratton
A 24-year-old nulliparous woman developed mildly elevated blood pressure (140–150/90–100 mmHg) without proteinuria (20 mg protein in a 24-hour urine collection) at 306/7 weeks of gestation. The fetus was small for gestational age (estimated fetal weight under the fifth percentile). At 325/7 weeks of gestation, the patient complained of epigastric pain, blood pressure was 180/110 mmHg, proteinuria was documented (780 mg protein in a 24-hour urine collection), schistocytes were detected in the peripheral smear, platelet count was 60,000 cells per mm3, and serum glutamic oxaloacetic transaminase was 234 U/l. The patient was diagnosed with severe preeclampsia/HELLP syndrome. Antenatal steroids were administered to induce fetal lung maturity. She and her family want to know the causes of this condition, what treatment is available, and whether there are any long-term implications of this diagnosis.
Roberto Romero, Tinnakorn Chaiworapongsa
Suppressing unwanted humoral immune responses without compromising the host’s ability to respond to foreign pathogens is a primary goal for therapies aimed at ameliorating harmful autoantibody production. Global suppression of the immune system via lymphocyte depletion and/or immunosuppressive drugs can have off-target effects, a limitation to conventional therapies. In this issue of the
Craig P. Chappell, Edward A. Clark
Mixed-lineage leukemia (MLL; also known as myeloid/lymphoid), the human homolog of trithorax in
Jens U. Marquardt, Snorri S. Thorgeirsson
Adenoid cystic carcinoma (ACC), a relatively rare malignancy usually of salivary gland origin, has a signature v-myb avian myeloblastosis viral oncogene homolog–nuclear factor I/B (
Henry F. Frierson Jr., Christopher A. Moskaluk
Intrahepatic cholestasis of pregnancy (ICP), marked by elevated maternal serum bile acid levels, occurs in late pregnancy and is often associated with poor perinatal outcomes. In this issue of the
Susan K. Murphy
Intrarenal control mechanisms play an important role in the maintenance of body fluid and electrolyte balance and pH homeostasis. Recent discoveries of new ion transport and regulatory pathways in the distal nephron and collecting duct system have helped to better our understanding of these critical kidney functions and identified new potential therapeutic targets and approaches. In this issue of the
Amyloid-β (Aβ) induces neuronal loss and cognitive deficits and is believed to be a prominent cause of Alzheimer’s disease (AD); however, the cellular pathology of the disease is not fully understood. Here, we report that IgG Fcγ receptor II-b (FcγRIIb) mediates Aβ neurotoxicity and neurodegeneration. We found that FcγRIIb is significantly upregulated in the hippocampus of AD brains and neuronal cells exposed to synthetic Aβ. Neuronal FcγRIIb activated ER stress and caspase-12, and
Tae-In Kam, Sungmin Song, Youngdae Gwon, Hyejin Park, Ji-Jing Yan, Isak Im, Ji-Woo Choi, Tae-Yong Choi, Jeongyeon Kim, Dong-Keun Song, Toshiyuki Takai, Yong-Chul Kim, Key-Sun Kim, Se-Young Choi, Sukwoo Choi, William L. Klein, Junying Yuan, Yong-Keun Jung
The skin interstitium sequesters excess Na+ and Cl– in salt-sensitive hypertension. Mononuclear phagocyte system (MPS) cells are recruited to the skin, sense the hypertonic electrolyte accumulation in skin, and activate the tonicity-responsive enhancer-binding protein (TONEBP, also known as NFAT5) to initiate expression and secretion of VEGFC, which enhances electrolyte clearance via cutaneous lymph vessels and increases eNOS expression in blood vessels. It is unclear whether this local MPS response to osmotic stress is important to systemic blood pressure control. Herein, we show that deletion of
Helge Wiig, Agnes Schröder, Wolfgang Neuhofer, Jonathan Jantsch, Christoph Kopp, Tine V. Karlsen, Michael Boschmann, Jennifer Goss, Maija Bry, Natalia Rakova, Anke Dahlmann, Sven Brenner, Olav Tenstad, Harri Nurmi, Eero Mervaala, Hubertus Wagner, Franz-Xaver Beck, Dominik N. Müller, Dontscho Kerjaschki, Friedrich C. Luft, David G. Harrison, Kari Alitalo, Jens Titze
Chronic cannabis exposure can lead to cerebellar dysfunction in humans, but the neurobiological mechanisms involved remain incompletely understood. Here, we found that in mice, subchronic administration of the psychoactive component of cannabis, delta9-tetrahydrocannabinol (THC), activated cerebellar microglia and increased the expression of neuroinflammatory markers, including IL-1β. This neuroinflammatory phenotype correlated with deficits in cerebellar conditioned learning and fine motor coordination. The neuroinflammatory phenotype was readily detectable in the cerebellum of mice with global loss of the CB1 cannabinoid receptor (CB1R,
Laura Cutando, Arnau Busquets-Garcia, Emma Puighermanal, Maria Gomis-González, José María Delgado-García, Agnès Gruart, Rafael Maldonado, Andrés Ozaita
Tumor-initiating stem-like cells (TICs) are resistant to chemotherapy and associated with hepatocellular carcinoma (HCC) caused by HCV and/or alcohol-related chronic liver injury. Using HCV Tg mouse models and patients with HCC, we isolated CD133+ TICs and identified the pluripotency marker NANOG as a direct target of TLR4, which drives the tumor-initiating activity of TICs. These TLR4/NANOG–dependent TICs were defective in the TGF-β tumor suppressor pathway. Functional oncogene screening of a TIC cDNA library identified
Chia-Lin Chen, Hidekazu Tsukamoto, Jian-Chang Liu, Claudine Kashiwabara, Douglas Feldman, Linda Sher, Steven Dooley, Samuel W. French, Lopa Mishra, Lydia Petrovic, Joseph H. Jeong, Keigo Machida
Influenza A viruses cause significant morbidity and mortality worldwide. There is a need for alternative or adjunct therapies, as resistance to currently used antiviral drugs is emerging rapidly. We tested ligand epitope antigen presentation system (LEAPS) technology as a new immune-based treatment for influenza virus infection in a mouse model. Influenza-J-LEAPS peptides were synthesized by conjugating the binding ligand derived from the β2-microglobulin chain of the human MHC class I molecule (J-LEAPS) with 15 to 30 amino acid–long peptides derived from influenza virus NP, M, or HA proteins. DCs were stimulated with influenza-J-LEAPS peptides (influenza-J-LEAPS) and injected intravenously into infected mice. Antigen-specific LEAPS-stimulated DCs were effective in reducing influenza virus replication in the lungs and enhancing survival of infected animals. Additionally, they augmented influenza-specific T cell responses in the lungs and reduced the severity of disease by limiting excessive cytokine responses, which are known to contribute to morbidity and mortality following influenza virus infection. Our data demonstrate that influenza-J-LEAPS–pulsed DCs reduce virus replication in the lungs, enhance survival, and modulate the protective immune responses that eliminate the virus while preventing excessive cytokines that could injure the host. This approach shows promise as an adjunct to antiviral treatment of influenza virus infections.
Kobporn Boonnak, Leatrice Vogel, Marlene Orandle, Daniel Zimmerman, Eyal Talor, Kanta Subbarao
During human pregnancy, a subset of placental cytotrophoblasts (CTBs) differentiates into cells that aggressively invade the uterus and its vasculature, anchoring the progeny and rerouting maternal blood to the placenta. In preeclampsia (PE), CTB invasion is limited, reducing placental perfusion and/or creating intermittent flow. This syndrome, affecting 4%–8% of pregnancies, entails maternal vascular alterations (e.g., high blood pressure, proteinuria, and edema) and, in some patients, fetal growth restriction. The only cure is removal of the faulty placenta, i.e., delivery. Previously, we showed that defective CTB differentiation contributes to the placental component of PE, but the causes were unknown. Here, we cultured CTBs isolated from PE and control placentas for 48 hours, enabling differentiation and invasion. In various severe forms of PE, transcriptomics revealed common aberrations in CTB gene expression immediately after isolation, including upregulation of
Yan Zhou, Matthew J. Gormley, Nathan M. Hunkapiller, Mirhan Kapidzic, Yana Stolyarov, Victoria Feng, Masakazu Nishida, Penelope M. Drake, Katherine Bianco, Fei Wang, Michael T. McMaster, Susan J. Fisher
CD4+ T cells are critical regulators of immune responses, but their functional role in human breast cancer is relatively unknown. The goal of this study was to produce an image of CD4+ T cells infiltrating breast tumors using limited ex vivo manipulation to better understand the in vivo differences associated with patient prognosis. We performed comprehensive molecular profiling of infiltrating CD4+ T cells isolated from untreated invasive primary tumors and found that the infiltrating T cell subpopulations included follicular helper T (Tfh) cells, which have not previously been found in solid tumors, as well as Th1, Th2, and Th17 effector memory cells and Tregs. T cell signaling pathway alterations included a mixture of activation and suppression characterized by restricted cytokine/chemokine production, which inversely paralleled lymphoid infiltration levels and could be reproduced in activated donor CD4+ T cells treated with primary tumor supernatant. A comparison of extensively versus minimally infiltrated tumors showed that CXCL13-producing CD4+ Tfh cells distinguish extensive immune infiltrates, principally located in tertiary lymphoid structure germinal centers. An 8-gene Tfh signature, signifying organized antitumor immunity, robustly predicted survival or preoperative response to chemotherapy. Our identification of CD4+ Tfh cells in breast cancer suggests that they are an important immune element whose presence in the tumor is a prognostic factor.
Chunyan Gu-Trantien, Sherene Loi, Soizic Garaud, Carole Equeter, Myriam Libin, Alexandre de Wind, Marie Ravoet, Hélène Le Buanec, Catherine Sibille, Germain Manfouo-Foutsop, Isabelle Veys, Benjamin Haibe-Kains, Sandeep K. Singhal, Stefan Michiels, Françoise Rothé, Roberto Salgado, Hugues Duvillier, Michail Ignatiadis, Christine Desmedt, Dominique Bron, Denis Larsimont, Martine Piccart, Christos Sotiriou, Karen Willard-Gallo
Host response to cancer signals has emerged as a key factor in cancer development; however, the underlying molecular mechanism is not well understood. In this report, we demonstrate that activating transcription factor 3 (ATF3), a hub of the cellular adaptive response network, plays an important role in host cells to enhance breast cancer metastasis. Immunohistochemical analysis of patient tumor samples revealed that expression of ATF3 in stromal mononuclear cells, but not cancer epithelial cells, is correlated with worse clinical outcomes and is an independent predictor for breast cancer death. This finding was corroborated by data from mouse models showing less efficient breast cancer metastasis in
Chris C. Wolford, Stephen J. McConoughey, Swati P. Jalgaonkar, Marino Leon, Anand S. Merchant, Johnna L. Dominick, Xin Yin, Yiseok Chang, Erik J. Zmuda, Sandra A. O’Toole, Ewan K.A. Millar, Stephanie L. Roller, Charles L. Shapiro, Michael C. Ostrowski, Robert L. Sutherland, Tsonwin Hai
Metabolic reprogramming is an important driver of tumor progression; however, the metabolic regulators of tumor cell motility and metastasis are not understood. Here, we show that tumors maintain energy production under nutrient deprivation through the function of HSP90 chaperones compartmentalized in mitochondria. Using cancer cell lines, we found that mitochondrial HSP90 proteins, including tumor necrosis factor receptor–associated protein-1 (TRAP-1), dampen the activation of the nutrient-sensing AMPK and its substrate UNC-51–like kinase (ULK1), preserve cytoskeletal dynamics, and release the cell motility effector focal adhesion kinase (FAK) from inhibition by the autophagy initiator FIP200. In turn, this results in enhanced tumor cell invasion in low nutrients and metastatic dissemination to bone or liver in disease models in mice. Moreover, we found that phosphorylated ULK1 levels were correlated with shortened overall survival in patients with non–small cell lung cancer. These results demonstrate that mitochondrial HSP90 chaperones, including TRAP-1, overcome metabolic stress and promote tumor cell metastasis by limiting the activation of the nutrient sensor AMPK and preventing autophagy.
M. Cecilia Caino, Young Chan Chae, Valentina Vaira, Stefano Ferrero, Mario Nosotti, Nina M. Martin, Ashani Weeraratna, Michael O’Connell, Danielle Jernigan, Alessandro Fatatis, Lucia R. Languino, Silvano Bosari, Dario C. Altieri
The mechanisms by which deregulated nuclear factor erythroid-2–related factor 2 (NRF2) and kelch-like ECH-associated protein 1 (KEAP1) signaling promote cellular proliferation and tumorigenesis are poorly understood. Using an integrated genomics and 13C-based targeted tracer fate association (TTFA) study, we found that NRF2 regulates miR-1 and miR-206 to direct carbon flux toward the pentose phosphate pathway (PPP) and the tricarboxylic acid (TCA) cycle, reprogramming glucose metabolism. Sustained activation of NRF2 signaling in cancer cells attenuated miR-1 and miR-206 expression, leading to enhanced expression of PPP genes. Conversely, overexpression of miR-1 and miR-206 decreased the expression of metabolic genes and dramatically impaired NADPH production, ribose synthesis, and in vivo tumor growth in mice. Loss of NRF2 decreased the expression of the redox-sensitive histone deacetylase, HDAC4, resulting in increased expression of miR-1 and miR-206, and not only inhibiting PPP expression and activity but functioning as a regulatory feedback loop that repressed HDAC4 expression. In primary tumor samples, the expression of miR-1 and miR-206 was inversely correlated with PPP gene expression, and increased expression of NRF2-dependent genes was associated with poor prognosis. Our results demonstrate that microRNA-dependent (miRNA-dependent) regulation of the PPP via NRF2 and HDAC4 represents a novel link between miRNA regulation, glucose metabolism, and ROS homeostasis in cancer cells.
Anju Singh, Christine Happel, Soumen K. Manna, George Acquaah-Mensah, Julian Carrerero, Sarvesh Kumar, Poonam Nasipuri, Kristopher W. Krausz, Nobunao Wakabayashi, Ruby Dewi, Laszlo G. Boros, Frank J. Gonzalez, Edward Gabrielson, Kwok K. Wong, Geoffrey Girnun, Shyam Biswal
Spontaneous regression of neuroblastoma (NB) resembles the developmentally regulated programmed cell death (PCD) of sympathetic neurons. Regressing tumor cells express high levels of the nerve growth factor (NGF) receptors TRKA and p75NTR and are dependent on NGF for survival; however, the underlying molecular mechanism remains elusive. Here, we show that UNC5D, a dependence receptor that is directly targeted by p53 family members, is highly expressed in favorable NBs. NGF withdrawal strongly upregulated UNC5D, E2F1, and p53 in human primary favorable NBs. The induced UNC5D was cleaved by caspases 2/3, and the released intracellular fragment translocated into the nucleus and interacted with E2F1 to selectively transactivate the proapoptotic target gene. The cleavage of UNC5D and its induction of apoptosis were strongly inhibited by addition of netrin-1.
Yuyan Zhu, Yuanyuan Li, Seiki Haraguchi, Meng Yu, Miki Ohira, Toshinori Ozaki, Atsuko Nakagawa, Toshikazu Ushijima, Eriko Isogai, Haruhiko Koseki, Yohko Nakamura, Cuize Kong, Patrick Mehlen, Hirofumi Arakawa, Akira Nakagawara
Hormone therapies for advanced prostate cancer target the androgen receptor (AR) ligand-binding domain (LBD), but these ultimately fail and the disease progresses to lethal castration-resistant prostate cancer (CRPC). The mechanisms that drive CRPC are incompletely understood, but may involve constitutively active AR splice variants that lack the LBD. The AR N-terminal domain (NTD) is essential for AR activity, but targeting this domain with small-molecule inhibitors is complicated by its intrinsic disorder. Here we investigated EPI-001, a small-molecule antagonist of AR NTD that inhibits protein-protein interactions necessary for AR transcriptional activity. We found that EPI analogs covalently bound the NTD to block transcriptional activity of AR and its splice variants and reduced the growth of CRPC xenografts. These findings suggest that the development of small-molecule inhibitors that bind covalently to intrinsically disordered proteins is a promising strategy for development of specific and effective anticancer agents.
Jae-Kyung Myung, Carmen A. Banuelos, Javier Garcia Fernandez, Nasrin R. Mawji, Jun Wang, Amy H. Tien, Yu Chi Yang, Iran Tavakoli, Simon Haile, Kate Watt, Iain J. McEwan, Stephen Plymate, Raymond J. Andersen, Marianne D. Sadar
Hippocampal development is coordinated by both extracellular factors like GABA neurotransmission and intracellular components like DISC1. We previously reported that SLC12A2-dependent GABA depolarization and DISC1 coregulate hippocampal neuronal development, and 2 SNPs in these genes linked to mRNA expression interactively increase schizophrenia risk. Using functional MRI, we now confirm this biological interaction in vivo by showing in 2 independent samples of healthy individuals (total
Joseph H. Callicott, Emer L. Feighery, Venkata S. Mattay, Michael G. White, Qiang Chen, David A.A. Baranger, Karen F. Berman, Bai Lu, Hongjun Song, Guo-li Ming, Daniel R. Weinberger
Adenoid cystic carcinoma (ACC) is a rare malignancy that can occur in multiple organ sites and is primarily found in the salivary gland. While the identification of recurrent fusions of the
Philip J. Stephens, Helen R. Davies, Yoshitsugu Mitani, Peter Van Loo, Adam Shlien, Patrick S. Tarpey, Elli Papaemmanuil, Angela Cheverton, Graham R. Bignell, Adam P. Butler, John Gamble, Stephen Gamble, Claire Hardy, Jonathan Hinton, Mingming Jia, Alagu Jayakumar, David Jones, Calli Latimer, Stuart McLaren, David J. McBride, Andrew Menzies, Laura Mudie, Mark Maddison, Keiran Raine, Serena Nik-Zainal, Sarah O’Meara, Jon W. Teague, Ignacio Varela, David C. Wedge, Ian Whitmore, Scott M. Lippman, Ultan McDermott, Michael R. Stratton, Peter J. Campbell, Adel K. El-Naggar, P. Andrew Futreal
The DNA-dependent protein kinase catalytic subunit (DNA-PKcs; encoded by
Lisa Woodbine, Jessica A. Neal, Nanda-Kumar Sasi, Mayuko Shimada, Karen Deem, Helen Coleman, William B. Dobyns, Tomoo Ogi, Katheryn Meek, E. Graham Davies, Penny A. Jeggo
Recent evidence suggests that enhanced neutrophil extracellular trap (NET) formation activates plasmacytoid dendritic cells and serves as a source of autoantigens in SLE. We propose that aberrant NET formation is also linked to organ damage and to the premature vascular disease characteristic of human SLE. Here, we demonstrate enhanced NET formation in the New Zealand mixed 2328 (NZM) model of murine lupus. NZM mice also developed autoantibodies to NETs as well as the ortholog of human cathelicidin/LL37 (CRAMP), a molecule externalized in the NETs. NZM mice were treated with Cl-amidine, an inhibitor of peptidylarginine deiminases (PAD), to block NET formation and were evaluated for lupus-like disease activity, endothelial function, and prothrombotic phenotype. Cl-amidine treatment inhibited NZM NET formation in vivo and significantly altered circulating autoantibody profiles and complement levels while reducing glomerular IgG deposition. Further, Cl-amidine increased the differentiation capacity of bone marrow endothelial progenitor cells, improved endothelium-dependent vasorelaxation, and markedly delayed time to arterial thrombosis induced by photochemical injury. Overall, these findings suggest that PAD inhibition can modulate phenotypes crucial for lupus pathogenesis and disease activity and may represent an important strategy for mitigating cardiovascular risk in lupus patients.
Jason S. Knight, Wenpu Zhao, Wei Luo, Venkataraman Subramanian, Alexander A. O’Dell, Srilakshmi Yalavarthi, Jeffrey B. Hodgin, Daniel T. Eitzman, Paul R. Thompson, Mariana J. Kaplan
Due to their efficient transduction potential, adeno-associated virus (AAV) vectors are leading candidates for gene therapy in skeletal muscle diseases. However, immune responses toward the vector or transgene product have been observed in preclinical and clinical studies. TLR9 has been implicated in promoting AAV-directed immune responses, but vectors have not been developed to circumvent this barrier. To assess the requirement of TLR9 in promoting immunity toward AAV-associated antigens following skeletal muscle gene transfer in mice, we compared immunological responses in WT and
Susan M. Faust, Peter Bell, Benjamin J. Cutler, Scott N. Ashley, Yanqing Zhu, Joseph E. Rabinowitz, James M. Wilson
Peripheral neuropathic pain is a disabling condition resulting from nerve injury. It is characterized by the dysregulation of voltage-gated sodium channels (Navs) expressed in dorsal root ganglion (DRG) sensory neurons. The mechanisms underlying the altered expression of Navs remain unknown. This study investigated the role of the E3 ubiquitin ligase NEDD4-2, which is known to ubiquitylate Navs, in the pathogenesis of neuropathic pain in mice. The spared nerve injury (SNI) model of traumatic nerve injury–induced neuropathic pain was used, and an Nav1.7-specific inhibitor, ProTxII, allowed the isolation of Nav1.7-mediated currents. SNI decreased NEDD4-2 expression in DRG cells and increased the amplitude of Nav1.7 and Nav1.8 currents. The redistribution of Nav1.7 channels toward peripheral axons was also observed. Similar changes were observed in the nociceptive DRG neurons of
Cédric J. Laedermann, Matthieu Cachemaille, Guylène Kirschmann, Marie Pertin, Romain-Daniel Gosselin, Isabelle Chang, Maxime Albesa, Chris Towne, Bernard L. Schneider, Stephan Kellenberger, Hugues Abriel, Isabelle Decosterd
Clearance of invading pathogens is essential to preventing overwhelming inflammation and sepsis that are symptomatic of bacterial peritonitis. Macrophages participate in this innate immune response by engulfing and digesting pathogens, a process called phagocytosis. Oxidized phospholipids (OxPL) are danger-associated molecular patterns (DAMPs) generated in response to infection that can prevent the phagocytic clearance of bacteria. We investigated the mechanism underlying OxPL action in macrophages. Exposure to OxPL induced alterations in actin polymerization, resulting in spreading of peritoneal macrophages and diminished uptake of
Ulrich Matt, Omar Sharif, Rui Martins, Tanja Furtner, Lorene Langeberg, Riem Gawish, Immanuel Elbau, Ana Zivkovic, Karin Lakovits, Olga Oskolkova, Bianca Doninger, Andreas Vychytil, Thomas Perkmann, Gernot Schabbauer, Christoph J. Binder, Valery N. Bochkov, John D. Scott, Sylvia Knapp
Gas exchange in the lung occurs within alveoli, air-filled sacs composed of type 2 and type 1 epithelial cells (AEC2s and AEC1s), capillaries, and various resident mesenchymal cells. Here, we use a combination of in vivo clonal lineage analysis, different injury/repair systems, and in vitro culture of purified cell populations to obtain new information about the contribution of AEC2s to alveolar maintenance and repair. Genetic lineage-tracing experiments showed that surfactant protein C–positive (SFTPC-positive) AEC2s self renew and differentiate over about a year, consistent with the population containing long-term alveolar stem cells. Moreover, if many AEC2s were specifically ablated, high-resolution imaging of intact lungs showed that individual survivors undergo rapid clonal expansion and daughter cell dispersal. Individual lineage-labeled AEC2s placed into 3D culture gave rise to self-renewing “alveolospheres,” which contained both AEC2s and cells expressing multiple AEC1 markers, including HOPX, a new marker for AEC1s. Growth and differentiation of the alveolospheres occurred most readily when cocultured with primary PDGFRα+ lung stromal cells. This population included lipofibroblasts that normally reside close to AEC2s and may therefore contribute to a stem cell niche in the murine lung. Results suggest that a similar dynamic exists between AEC2s and mesenchymal cells in the human lung.
Christina E. Barkauskas, Michael J. Cronce, Craig R. Rackley, Emily J. Bowie, Douglas R. Keene, Barry R. Stripp, Scott H. Randell, Paul W. Noble, Brigid L.M. Hogan
Amélie Bonnefond, Anne Raimondo, Fanny Stutzmann, Maya Ghoussaini, Shwetha Ramachandrappa, David C. Bersten, Emmanuelle Durand, Vincent Vatin, Beverley Balkau, Olivier Lantieri, Violeta Raverdy, François Pattou, Wim Van Hul, Luc Van Gaal, Daniel J. Peet, Jacques Weill, Jennifer L. Miller, Fritz Horber, Anthony P. Goldstone, Daniel J. Driscoll, John B. Bruning, David Meyre, Murray L. Whitelaw, Philippe Froguel
Single-minded 1 (SIM1) is a basic helix-loop-helix transcription factor involved in the development and function of the paraventricular nucleus of the hypothalamus. Obesity has been reported in
Shwetha Ramachandrappa, Anne Raimondo, Anna M.G. Cali, Julia M. Keogh, Elana Henning, Sadia Saeed, Amanda Thompson, Sumedha Garg, Elena G. Bochukova, Soren Brage, Victoria Trowse, Eleanor Wheeler, Adrienne E. Sullivan, Mehul Dattani, Peter E. Clayton, Vippan Datta, John B. Bruning, Nick J. Wareham, Stephen O’Rahilly, Daniel J. Peet, Ines Barroso, Murray L. Whitelaw, I. Sadaf Farooqi
Glucocorticoid (GC) excess adversely affects skin integrity, inducing thinning and impaired wound healing. Aged skin, particularly that which has been photo-exposed, shares a similar phenotype. Previously, we demonstrated age-induced expression of the GC-activating enzyme 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) in cultured human dermal fibroblasts (HDFs). Here, we determined 11β-HSD1 levels in human skin biopsies from young and older volunteers and examined the aged 11β-HSD1 KO mouse skin phenotype. 11β-HSD1 activity was elevated in aged human and mouse skin and in PE compared with donor-matched photo-protected human biopsies. Age-induced dermal atrophy with deranged collagen structural organization was prevented in 11β-HSD1 KO mice, which also exhibited increased collagen density. We found that treatment of HDFs with physiological concentrations of cortisol inhibited rate-limiting steps in collagen biosynthesis and processing. Furthermore, topical 11β-HSD1 inhibitor treatment accelerated healing of full-thickness mouse dorsal wounds, with improved healing also observed in aged 11β-HSD1 KO mice. These findings suggest that elevated 11β-HSD1 activity in aging skin leads to increased local GC generation, which may account for adverse changes occurring in the elderly, and 11β-HSD1 inhibitors may be useful in the treatment of age-associated impairments in dermal integrity and wound healing.
Ana Tiganescu, Abd A. Tahrani, Stuart A. Morgan, Marcela Otranto, Alexis Desmoulière, Lianne Abrahams, Zaki Hassan-Smith, Elizabeth A. Walker, Elizabeth H. Rabbitt, Mark S. Cooper, Kurt Amrein, Gareth G. Lavery, Paul M. Stewart
Extended circulation of nanoparticles in blood is essential for most clinical applications. Nanoparticles are rapidly cleared by cells of the mononuclear phagocyte system (MPS). Approaches such as grafting polyethylene glycol onto particles (PEGylation) extend circulation times; however, these particles are still cleared, and the processes involved in this clearance remain poorly understood. Here, we present an intravital microscopy–based assay for the quantification of nanoparticle clearance, allowing us to determine the effect of mouse strain and immune system function on particle clearance. We demonstrate that mouse strains that are prone to Th1 immune responses clear nanoparticles at a slower rate than Th2-prone mice. Using depletion strategies, we show that both granulocytes and macrophages participate in the enhanced clearance observed in Th2-prone mice. Macrophages isolated from Th1 strains took up fewer particles in vitro than macrophages from Th2 strains. Treating macrophages from Th1 strains with cytokines to differentiate them into M2 macrophages increased the amount of particle uptake. Conversely, treating macrophages from Th2 strains with cytokines to differentiate them into M1 macrophages decreased their particle uptake. Moreover, these results were confirmed in human monocyte–derived macrophages, suggesting that global immune regulation has a significant impact on nanoparticle clearance in humans.
Stephen W. Jones, Reid A. Roberts, Gregory R. Robbins, Jillian L. Perry, Marc P. Kai, Kai Chen, Tao Bo, Mary E. Napier, Jenny P.Y. Ting, Joseph M. DeSimone, James E. Bear
Antibodies confer humoral immunity but can also be harmful when they target an autoantigen, alloantigen, allergen, or biotherapeutic. New strategies are needed for antigen-specific suppression of undesired antibody responses, particularly to T cell–dependent protein antigens, because they elicit T cell help. Here we show that liposomal nanoparticles, displaying both antigen and glycan ligands of the inhibitory coreceptor CD22, induce a tolerogenic program that selectively causes apoptosis in mouse and human B cells. These SIGLEC-engaging tolerance-inducing antigenic liposomes (STALs, where SIGLEC is defined as sialic acid–binding Ig-like lectin) induced robust antigen-specific tolerance to protein antigens in mice, preventing subsequent immune response to challenge with the same antigen. Since development of inhibitory antibodies to FVIII is a serious problem in treatment of hemophilia A patients, we investigated the potential of this approach for inducing tolerance to FVIII in a hemophilia mouse model. STALs prevented formation of inhibitory FVIII antibodies, allowing for effective administration of FVIII to hemophilia mice to prevent bleeding. These findings suggest that STALs could be used to eliminate or prevent harmful B cell–mediated immune responses.
Matthew S. Macauley, Fabian Pfrengle, Christoph Rademacher, Corwin M. Nycholat, Andrew J. Gale, Annette von Drygalski, James C. Paulson
Autosomal-dominant polycystic kidney disease (ADPKD) is caused by mutations in either
Xia Zhou, Lucy X. Fan, William E. Sweeney Jr., John M. Denu, Ellis D. Avner, Xiaogang Li
Acute lymphoblastic leukemia (ALL) is the commonest childhood malignancy and is characterized by recurring structural genetic alterations. Previous studies of DNA methylation suggest epigenetic alterations may also be important, but an integrated genome-wide analysis of genetic and epigenetic alterations in ALL has not been performed. We analyzed 137 B-lineage and 30 T-lineage childhood ALL cases using microarray analysis of DNA copy number alterations and gene expression, and genome-wide cytosine methylation profiling using the
Maria E. Figueroa, Shann-Ching Chen, Anna K. Andersson, Letha A. Phillips, Yushan Li, Jason Sotzen, Mondira Kundu, James R. Downing, Ari Melnick, Charles G. Mullighan
Histone deacetylase 3 (HDAC3) contributes to the regulation of gene expression, chromatin structure, and genomic stability. Because HDAC3 associates with oncoproteins that drive leukemia and lymphoma, we engineered a conditional deletion allele in mice to explore the physiological roles of
Alyssa R. Summers, Melissa A. Fischer, Kristy R. Stengel, Yue Zhao, Jonathan F. Kaiser, Christina E. Wells, Aubrey Hunt, Srividya Bhaskara, Jessica W. Luzwick, Shilpa Sampathi, Xi Chen, Mary Ann Thompson, David Cortez, Scott W. Hiebert
Misfolding of exportable proteins can trigger endocrinopathies. For example, misfolding of insulin can result in autosomal dominant mutant
Jordan Wright, Xiaofan Wang, Leena Haataja, Aaron P. Kellogg, Jaemin Lee, Ming Liu, Peter Arvan
Jens Dannull, N. Rebecca Haley, Gary Archer, Smita Nair, David Boczkowski, Mark Harper, Nicole De Rosa, Nancy Pickett, Paul J. Mosca, James Burchette, Maria A. Selim, Duane A. Mitchell, John Sampson, Douglas S. Tyler, Scott K. Pruitt
Diabetes is a disorder characterized by loss of β cell mass and/or β cell function, leading to deficiency of insulin relative to metabolic need. To determine whether stem cell–derived β cells recapitulate molecular-physiological phenotypes of a diabetic subject, we generated induced pluripotent stem cells (iPSCs) from subjects with maturity-onset diabetes of the young type 2 (MODY2), which is characterized by heterozygous loss of function of the gene encoding glucokinase (
Haiqing Hua, Linshan Shang, Hector Martinez, Matthew Freeby, Mary Pat Gallagher, Thomas Ludwig, Liyong Deng, Ellen Greenberg, Charles LeDuc, Wendy K. Chung, Robin Goland, Rudolph L. Leibel, Dieter Egli
HGF signals through its cognate receptor, MET, to orchestrate diverse biological processes, including cell proliferation, cell fate specification, organogenesis, and epithelial-mesenchymal transition. Mixed-lineage leukemia (MLL), an epigenetic regulator, plays critical roles in cell fate, stem cell, and cell cycle decisions. Here, we describe a role for MLL in the HGF-MET signaling pathway. We found a shared phenotype among
Shugaku Takeda, Han Liu, Satoru Sasagawa, Yiyu Dong, Paul A. Trainor, Emily H. Cheng, James J. Hsieh
Paracrine communication between different parts of the renal tubule is increasingly recognized as an important determinant of renal function. Previous studies have shown that changes in dietary acid-base load can reverse the direction of apical α-ketoglutarate (αKG) transport in the proximal tubule and Henle’s loop from reabsorption (acid load) to secretion (base load). Here we show that the resulting changes in the luminal concentrations of αKG are sensed by the αKG receptor OXGR1 expressed in the type B and non-A–non-B intercalated cells of the connecting tubule (CNT) and the cortical collecting duct (CCD). The addition of 1 mM αKG to the tubular lumen strongly stimulated Cl–-dependent HCO3– secretion and electroneutral transepithelial NaCl reabsorption in microperfused CCDs of wild-type mice but not
Natsuko Tokonami, Luciana Morla, Gabriel Centeno, David Mordasini, Suresh Krishna Ramakrishnan, Svetlana Nikolaeva, Carsten A. Wagner, Olivier Bonny, Pascal Houillier, Alain Doucet, Dmitri Firsov
The intrauterine environment is a major contributor to increased rates of metabolic disease in adults. Intrahepatic cholestasis of pregnancy (ICP) is a liver disease of pregnancy that affects 0.5%–2% of pregnant women and is characterized by increased bile acid levels in the maternal serum. The influence of ICP on the metabolic health of offspring is unknown. We analyzed the Northern Finland birth cohort 1985–1986 database and found that 16-year-old children of mothers with ICP had altered lipid profiles. Males had increased BMI, and females exhibited increased waist and hip girth compared with the offspring of uncomplicated pregnancies. We further investigated the effect of maternal cholestasis on the metabolism of adult offspring in the mouse. Females from cholestatic mothers developed a severe obese, diabetic phenotype with hepatosteatosis following a Western diet, whereas matched mice not exposed to cholestasis in utero did not. Female littermates were susceptible to metabolic disease before dietary challenge. Human and mouse studies showed an accumulation of lipids in the fetoplacental unit and increased transplacental cholesterol transport in cholestatic pregnancy. We believe this is the first report showing that cholestatic pregnancy in the absence of altered maternal BMI or diabetes can program metabolic disease in the offspring.
Georgia Papacleovoulou, Shadi Abu-Hayyeh, Evanthia Nikolopoulou, Oscar Briz, Bryn M. Owen, Vanya Nikolova, Caroline Ovadia, Xiao Huang, Marja Vaarasmaki, Marc Baumann, Eugene Jansen, Christiane Albrecht, Marjo-Riitta Jarvelin, Jose J.G. Marin, A.S. Knisely, Catherine Williamson
Deborah A. Knight, Shin Foong Ngiow, Ming Li, Tiffany Parmenter, Stephen Mok, Ashley Cass, Nicole M. Haynes, Kathryn Kinross, Hideo Yagita, Richard C. Koya, Thomas G. Graeber, Antoni Ribas, Grant A. McArthur, Mark J. Smyth
Stavros C. Manolagas
Kfir Lapid, Tomer Itkin, Gabriele D’Uva, Yossi Ovadya, Aya Ludin, Giulia Caglio, Alexander Kalinkovich, Karin Golan, Ziv Porat, Massimo Zollo, Tsvee Lapidot
Sampurna Chatterjee, Lukas C. Heukamp, Maike Siobal, Jakob Schöttle, Caroline Wieczorek, Martin Peifer, Davide Frasca, Mirjam Koker, Katharina König, Lydia Meder, Daniel Rauh, Reinhard Buettner, Jürgen Wolf, Rolf A. Brekken, Bernd Neumaier, Gerhard Christofori, Roman K. Thomas, Roland T. Ullrich