Research
Abstract
Chikungunya is a mosquito-borne disease that causes periodic but explosive epidemics of acute disease throughout the tropical world. Vaccine development against chikungunya virus (CHIKV) has been hampered by the inability to conduct efficacy trials due to the unpredictability of CHIKV outbreaks. Therefore, immune correlates are being explored to gain inference into vaccine-induced protection. Current study is an in-depth serological characterization of Fab and Fc-mediated antibody responses in selected Phase 2 clinical trial participants following immunization with the recombinant measles-vectored CHIKV vaccine, MV-CHIK. Antibody comparisons were conducted between participants who received prime versus prime-boost vaccine regimens. MV-CHIK vaccination elicited potent Fab-mediated antibodies (such as CHIKV-specific IgG, neutralization and avidity), including dominant IgG3 responses which translated into strong antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP). At 1-month, prime-boost immunization lead to significantly greater responses in every measured Fab and Fc antibody parameter. Interestingly, prime-boost-elicited antibodies decreased rapidly over time, until at 6-months both vaccine regimens displayed similar antibody profiles. Nonetheless, antibody avidity and ADCP remained significantly greater following boost immunization. Our observations suggest that a prime-boost administration of MV-CHIK will be more appropriate for CHIKV-endemic regions, while a prime only regimen may be sufficient for travel purposes or outbreak situations.
Authors
Roland Tschismarov, Raphaël M. Zellweger, Min Jie Koh, Yan Shan Leong, Jenny G. Low, Eng Eong Ooi, Christian W. Mandl, Katrin Ramsauer, Ruklanthi de Alwis
Abstract
mascRNA is a highly conserved tRNA-like noncoding RNA whose function remains largely unknown. We show here that this small RNA molecule played a role in the stringent control of Toll-like receptor (TLR)-mediated innate immune responses. mascRNA inhibited activation of NF-κB and mitogen-activated protein kinase (MAPK) signaling and the production of inflammatory cytokines in macrophages stimulated with lipopolysaccharide (LPS), a TLR4 ligand. Furthermore, exogenous mascRNA alleviated LPS-induced lung inflammation. On the contrary, mascRNA potentiated the phosphorylation of IRF3 and STAT1 and the transcription of interferon-related genes in response to the TLR3 ligand poly(I:C) both in vitro and in vivo. Mechanistically, mascRNA was found to enhance K48-linked ubiquitination and proteasomal degradation of TRAF6, thereby negatively regulating TLR-mediated MyD88-dependent proinflammatory signaling while positively regulating TRIF-dependent interferon signaling. Additionally, hnRNP H and hnRNP F were found to interact with mascRNA, promote its degradation, and contribute to the fine-tuning of TLR-triggered immune responses. Taken together, our data identify a dual role of mascRNA in both negative and positive regulation of innate immune responses.
Authors
Tao Sun, Chunxue Wei, Daoyong Wang, Xuxu Wang, Jiao Wang, Yuqing Hu, Xiaohua Mao
Abstract
Fibrotic posterior capsular opacification (PCO), a major complication of cataract surgery, is driven by transforming growth factor β (TGFβ). Previously, αV integrins were found to be critical for the onset of TGFβ-mediated PCO in vivo, however, the functional heterodimer was unknown. Here, β8 integrin conditional knockout (β8ITGcKO) lens cells (LCs) were observed to attenuate their fibrotic responses, while both β5 and β6 integrin null LCs underwent fibrotic changes similar to WT at 5 days PCS. RNAseq revealed that β8ITGcKO LCs attenuated their upregulation of integrins and their ligands, as well as known targets of TGFβ induced signaling at 24 hours PCS. Treatment of β8ITGcKO eyes with active TGFβ1 at the time of surgery rescued the fibrotic response. Treatment of wild type mice with an anti- αVβ8 integrin function blocking antibody at the time of surgery ameliorated both canonical TGFβ signaling and LC fibrotic response PCS, and treatment at 5 days PCS, after surgically induced fibrotic responses are established, largely reversed this fibrotic response. These data suggest that αVβ8 integrin is a major regulator of TGFβ activation by LCs PCS and that therapeutics targeting αVβ8 integrin could be effective for fibrotic PCO prevention and treatment.
Authors
Mahbubul H. Shihan, Samuel G. Novo, Yan Wang, Dean Sheppard, Amha Atakilit, Thomas D. Arnold, Nicole M. Rossi, Adam P. Faranda, Melinda K. Duncan
Abstract
Cytokine-producing CD4+ T cells play a crucial role in the control of Mycobacterium tuberculosis (Mtb) infection; however, there is a delayed appearance of effector T cells in the lungs following aerosol infection. The immunomodulatory cytokine IL-10 antagonizes control of Mtb infection through mechanisms associated with reduced CD4+ T cell responses. Here, we show that IL-10 overexpression only before the onset of the T cell response impairs control of Mtb growth. During chronic infection, IL-10 overexpression reduces the CD4+ T cell response without impacting the outcome of infection. IL-10 overexpression early during infection did not significantly impair the kinetics of CD4+ T cell priming and effector differentiation; however, CD4+ T cells primed and differentiated in a IL-10-enriched environment display reduced expression of CXCR3 and do not migrate into the lung parenchyma thereby limiting their ability to control infection. Importantly, these CD4+ T cells maintain their vasculature phenotype and are unable to control infection even after adoptively transferred into low IL-10 settings. Together our data support a model wherein, during Mtb infection, IL-10 acts intrinsically on T cells impairing their parenchymal migratory capacity and ability to engage with infected phagocytic cells thereby impeding control of infection.
Authors
Catarina M. Ferreira, Ana Margarida Barbosa, Palmira Barreira-Silva, Ricardo Silvestre, Cristina Cunha, Agostinho Carvalho, Fernando Rodrigues, Margarida Correia-Neves, António G. Castro, Egídio Torrado
Abstract
Interleukin-33 (IL-33), a nuclear alarmin released during cell death, exerts context-specific effects on adaptive and innate immune cells eliciting potent inflammatory responses. We screened blood, skin and kidney tissues from patients with Systemic Lupus Erythematosus (SLE), a systemic autoimmune disease driven by unabated type I interferon (IFN) production, and found increased amounts of extracellular IL-33 complexed with Neutrophil Extracellular Traps (NETs), correlating with severe, active disease. Using a combination of molecular, imaging and proteomic approaches, we show that SLE neutrophils -activated by disease immunocomplexes- release IL-33-decorated NETs that stimulate robust IFNα synthesis by plasmacytoid dendritic cells (pDCs) in an IL-33-receptor (ST2L)-dependent manner. IL33-silenced neutrophil-like cells cultured under lupus-inducing conditions generated NETs with diminished interferogenic effect. Importantly, SLE patient-derived NETs are enriched in mature bioactive isoforms of IL-33 processed by the neutrophil proteases elastase and cathepsin G. Pharmacological inhibition of these proteases neutralized IL-33-dependent IFNα production elicited by NETs. These data demonstrate a novel role for cleaved IL-33 alarmin decorating NETs in human SLE, linking neutrophil activation, type I IFN production and end-organ inflammation with skin pathology mirroring that observed in the kidneys.
Authors
Spiros Georgakis, Katerina Gkirtzimanaki, Garyfalia Papadaki, Hariklia Gakiopoulou, Elias Drakos, Maija-Leena Eloranta, Manousos Makridakis, Georgia Kontostathi, Jerome Zoidakis, Eirini Baira, Lars Rönnblom, Dimitrios T. Boumpas, Prodromos Sidiropoulos, Panayotis Verginis, George Bertsias
Abstract
Ozone is a highly reactive environmental pollutant with well-recognized adverse effects on lung health. Bronchial hyperactivity (BHR) is one consequence of ozone exposure, particularly for individuals with underlying lung disease. Our data demonstrate ozone induces substantial ATP release from human airway epithelia in vitro and into the airways of mice in vivo, and that ATP is a potent inducer of mast cell degranulation and BHR, acting through P2X7 receptors on mast cells. Both mast cell-deficient and P2X7 receptor-deficient (P2XT-/-) mice demonstrate markedly attenuated BHR to ozone. Re-constitution of mast cell-deficient mice with WT mast cells and P2X7-/- mast cells restores ozone-induced BHR. Despite equal numbers of mast cells in reconstituted mouse lungs, mice reconstituted with P2X7-/- mast cells demonstrated significantly less robust BHR than mice reconstituted with WT mast cells. These results support a model where P2X7 on both mast cells and other cell types contribute to ozone-induce BHR.
Authors
Xiaomei Kong, William C. Bennett, Corey M. Jania, Kelly D. Chason, Zachary German, Jennifer Adouli, Samuel D. Budney, Brandon T. Oby, Catharina van Heusden, Eduardo R. Lazarowski, Ilona Jaspers, Scott H. Randell, Barry A. Hedgespeth, Glenn Cruse, Xiaoyang Hua, Stephen A. Schworer, Gregory J. Smith, Samir N. P. Kelada, Stephen L. Tilley
Abstract
The epidermal growth factor receptor (EGFR) inhibitor cetuximab is the only FDA-approved oncogene-targeting therapy for head and neck squamous cell carcinoma (HNSCC). Despite variable treatment response, no biomarkers exist to stratify patients for cetuximab therapy in HNSCC. Here, we applied unbiased hierarchical clustering to reverse phase protein array (RPPA) molecular profiles from patient-derived xenograft (PDX) tumors, which revealed two PDX clusters defined by protein networks associated with EGFR inhibitor resistance. In vivo validation revealed unbiased clustering to classify PDX tumors with 88% accuracy. Next, a support vector machine (SVM) classifier algorithm identified a minimalist biomarker signature consisting of eight proteins – Caveolin-1, Sox-2, AXL, STING, Brd4, Claudin-7, Connexin-43, and Fibronectin – whose expression strongly predicted cetuximab response in PDXs using either protein (AUC=0.95) or mRNA (AUC=0.97). A combination of Caveolin-1 and Sox-2 protein levels was sufficient to maintain high predictive accuracy, which we validated in HNSCC patient tumor samples with known clinical response to cetuximab. These results support further investigation into the combined use of Caveolin-1 and Sox-2 as predictive biomarkers for cetuximab response in the clinic.
Authors
Mehdi Bouhaddou, Rex H. Lee, Hua Li, Neil E. Bhola, Rachel A. O'Keefe, Mohammad Naser, Tian Ran Zhu, Kelechi Nwachuku, Umamaheswar Duvvuri, Adam B. Olshen, Ritu Roy, Aaron Hechmer, Jennifer Bolen, Stephen B. Keysar, Antonio Jimeno, Gordon B. Mills, Scott Vandenberg, Danielle L. Swaney, Daniel E. Johnson, Nevan J. Krogan, Jennifer R. Grandis
Abstract
Hidradenitis suppurativa (HS) is a chronic, inflammatory skin disorder characterized by recurrent abscesses in the groin and flexural areas. HS is associated with a wide range of comorbidities that complicate the disease course. Although these comorbidities have been well-described, it remains unclear how these comorbidities co-associate and whether comorbidity profiles affect disease trajectory. In addition, it is unknown how comorbidity associations are modulated by race and gender. In this comprehensive analysis of 77 million patients in a large U.S. population-based cohort, we examine co-association patterns among HS comorbidities and identify clinically relevant phenotypic subtypes within HS. We demonstrate that these subtypes not only differ among races, but also influence clinical outcomes as measured by HS-related emergency department (ED) visits and cellulitis. Taken together, our findings provide key insights that elucidate the unique disease trajectories experienced by HS patients, and equip clinicians with a novel framework for risk stratification and improved targeted care in HS.
Authors
Vivian J. Hua, James M. Kilgour, Hyunje G. Cho, Shufeng Li, Kavita Y. Sarin
Abstract
We recently described a previously unknown trans-tentorial venous system (TTVS) connecting venous drainage throughout the brain in humans. Prior to this finding, it was believed that the embryologic tentorial plexus regresses, resulting in a largely avascular tentorium. Our finding contradicted this understanding and necessitated further investigation into the development of the newly described TTVS. Herein we sought to investigate mice as a model to study the development of this system. First, using vascular casting and ex vivo micro-computed tomography (micro-CT), we demonstrate that this TTVS is conserved in adult mice. Next, using high-resolution magnetic resonance imaging (MRI), we found the primitive tentorial venous plexus in murine embryo at day 14.5. We also found that, at this embryologic stage, the tentorial plexus drains the choroid plexus. Finally, using vascular casting and micro-CT, we found that the TTVS is the dominant venous drainage in the early postnatal period (P8). Herein, we demonstrate that the TTVS is conserved between mice and humans and present a longitudinal study of its development. In addition, our findings establish mice as a translational model for further study of this newly described system and its relationship to intracranial physiology.
Authors
Pashayar P. Lookian, Vikram Chandrashekhar, Anthony Cappadona, Jean-Paul Bryant, Vibhu Chandrashekhar, Jessa M. Tunacao, Danielle R. Donahue, Jeeva P. Munasinghe, James G. Smirniotopoulos, John D. Heiss, Zhengping Zhuang, Jared S. Rosenblum
Abstract
Mutations in the cilium-associated protein CEP290 cause retinal degeneration as part of multi-organ ciliopathies or as retina-specific diseases. The precise location and the functional roles of CEP290 within cilia and, specifically, the connecting cilia (CC) of photoreceptors, remain unclear. We used superresolution fluorescence microscopy and electron microscopy (TEM) to localize CEP290 in the CC and in primary cilia of cultured cells with sub-diffraction resolution, and to determine effects of CEP290 deficiency in three mutant models. Radially, CEP290 localizes in close proximity to the microtubule doublets in the region between the doublets and the ciliary membrane. Longitudinally, it is distributed throughout the length of the CC whereas it is confined to the very base of primary cilia in hRPE-1 cells. We found Y-shaped links, ciliary sub-structures between microtubules and membrane, throughout the length of the CC. Severe CEP290 deficiencies in mouse models did not prevent assembly of cilia or cause obvious mislocalization of ciliary components in early stages of degeneration. There were fewer cilia and no normal outer segments in the mutants, but the Y-shaped links were clearly present. These results point to photoreceptor-specific functions of CEP290 essential for CC maturation and stability following the earliest stages of ciliogenesis.
Authors
Valencia L. Potter, Abigail R. Moye, Michael A. Robichaux, Theodore G. Wensel
No posts were found with this tag.
