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CCI orders fresh probe against DLF firm for Gurgaon project

New Delhi : The Competition Commission of India (CCI) has ordered a fresh probe against a DLF group firm, DLF Universal, for allegedly imposing unfair and unreasonable conditions on office buyers at one of its commercial projects — Corporate Greens at Sector 74A — in Gurgaon. CCI said in its 11-page order dated June 23 that “the conduct of DLF Group, emanating from its dominant position in the relevant market, prima facie, amounts to imposition of unfair terms and conditions on the commercial office buyers which is anti-competitive”. After looking into the complaint, CCI said its prima facie opinion was that despite the presence of other developer in commercial real […]




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SHC tells home dept to decide banned outfit activist's plea against detention in a week

The Sindh High Court has directed the home department to decide the representation of a proscribed organisation’s activist against his 90 days’ detention under the Maintenance of Public Order within a week.The activist, Abdul Hameed Bugti, had been recently released in the Pakistan...




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Protect Against Rootkit and Bootkit Malware in Systems that Boot from External SPI Flash Memory

Protect Against Rootkit and Bootkit Malware in Systems that Boot from External SPI Flash Memory




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‘Language revolt': This activist tweets against erasure of first languages in South Africa

A language reclamation activist confronts linguistic imperialism and the dehumanisation of two South African first languages through digital inclusion advocacy.




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Fiji general cites need to ‘stifle criticism’ in the fight against the COVID-19 pandemic

"The COVID-19 pandemic is not an excuse for human rights violations. Excessive force and brutality are unacceptable from any of our enforcement or security forces."




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Nigerian atheist faces death threats for blasphemy against Islam

"Nigeria is a secular state and freedom of speech is one of the fundamental characteristics of a modern democratic state. Criticizing a religion is not a criminal offence."





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Institutional and Governance Dimensions of Flood Risk Management: A Flood Footprint and Accountability Mechanism

This working paper proposes flood footprint and accountability to coordinate risk management projects through appropriate spatial planning at river basin scale.




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AVR Instruction Set Manual

AVR Instruction Set Manual




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Einstein’s black holes are not the black holes we see in reality

We’re only just grasping how cosmic black holes and Einstein’s theories relate – and that deepens our sense of wonder, says Chanda Prescod-Weinstein




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Bye bye space-time: is it time to free physics from Einstein’s legacy?

Einstein’s framework for the universe, space-time, is at odds with quantum theory. Overcoming this clash and others is vital to unravelling the true nature of the cosmos




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Einstein killed the aether. Now the idea is back to save relativity

The luminiferous aether has become a byword for failed ideas. Now it is being revived to explain dark matter and dark energy, and potentially unify physics




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U.S. watchdog agency says coronavirus whistleblower should be reinstated

A U.S. government watchdog agency has recommended the temporary reinstatement of a whistleblower who says he was removed as director of a government research office because he raised concerns about coronavirus preparedness, his lawyers said on Friday.




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The City We Became review: N. K. Jemisin pits New York against aliens

N. K. Jemisin's latest book sees New York itself come alive to fight off aliens in the first part of a new trilogy with ethnicity at its heart




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'Play It Loud: Instruments of Rock & Roll' exhibit set to launch at New York's 'Met' Museum

It's only 'Rock and Roll,' but one of the world's preeminent museums likes it; New York's Metropolitan Museum of Art will display instruments from Chuck Berry, The Rolling Stones, Kurt Cobain, Lady Gaga and more until October 1. Rough Cut. (No Reporter Narration.)




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Einstein's jacket and Apollo 11 tapes: Inside the science auction

Fancy bidding on a Christmas present steeped in science history? Find out what they'll set you back, and which present-day artefacts might be worth investing in




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How soon will we have a coronavirus vaccine? The race against covid-19

The hope is that we will have a coronavirus vaccine in 12-18 months, but for that to happen we may have to rely on untested techniques - and that comes with its own risks.




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UPDATE 2-IMF's Georgieva downbeat on global economic forecast, warns against protectionism

The head of the International Monetary Fund on Friday signaled a possible downward revision of global economic forecasts, and warned the United States and China against rekindling a trade war that could weaken a recovery from the coronavirus pandemic.




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DOJ to drop case against Trump ex-advisor Flynn

The U.S. Justice Department on Thursday abruptly asked a judge to drop criminal charges against President Donald Trump's former national security adviser Michael Flynn following mounting pressure from Trump and his political allies on the right. This report produced by Jillian Kitchener.




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Tabloid wins initial court battle against UK royal Meghan

London's High Court on Friday threw out part of a claim brought by Meghan, Britain's Duchess of Sussex, against a tabloid newspaper for breaching her privacy, ruling that it had not acted dishonestly. Lauren Anthony reports.




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BCG vaccine being trialled as potential protection against covid-19

A long-standing hypothesis suggests the BCG vaccine also serves to generally enhance the immune system, meaning it could protect against covid-19, and trials are under way to find out




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DOJ to drop case against Trump ex-advisor Flynn

The U.S. Justice Department on Thursday abruptly asked a judge to drop criminal charges against President Donald Trump's former national security adviser Michael Flynn following mounting pressure from Trump and his political allies on the right. This report produced by Jillian Kitchener.




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Will Brushing and Flossing Protect You Against Stroke?

Title: Will Brushing and Flossing Protect You Against Stroke?
Category: Health News
Created: 2/13/2020 12:00:00 AM
Last Editorial Review: 2/14/2020 12:00:00 AM




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Drug May Help Against Inflammatory Breast Cancer

Title: Drug May Help Against Inflammatory Breast Cancer
Category: Health News
Created: 4/27/2009 9:26:00 AM
Last Editorial Review: 4/27/2009 12:00:00 AM




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Health Tip: Installing a Playground at Home

Title: Health Tip: Installing a Playground at Home
Category: Health News
Created: 4/30/2012 8:05:00 AM
Last Editorial Review: 4/30/2012 12:00:00 AM




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Lower-Dose Radioiodine Effective Against Thyroid Cancer

Title: Lower-Dose Radioiodine Effective Against Thyroid Cancer
Category: Health News
Created: 5/2/2012 6:06:00 PM
Last Editorial Review: 5/3/2012 12:00:00 AM




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Muhammad Ali's Daughter Champions Fight Against Parkinson's Disease

Title: Muhammad Ali's Daughter Champions Fight Against Parkinson's Disease
Category: Health News
Created: 5/3/2013 10:35:00 AM
Last Editorial Review: 5/3/2013 12:00:00 AM




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FDA Warns Against Bogus Autism Treatments

Title: FDA Warns Against Bogus Autism Treatments
Category: Health News
Created: 4/25/2014 2:36:00 PM
Last Editorial Review: 4/28/2014 12:00:00 AM




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Vaccine Against Bird Flu Readied, Just in Case

Title: Vaccine Against Bird Flu Readied, Just in Case
Category: Health News
Created: 4/30/2014 2:36:00 PM
Last Editorial Review: 5/1/2014 12:00:00 AM




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How Transplanted Livers Guard Against Organ Rejection

Title: How Transplanted Livers Guard Against Organ Rejection
Category: Health News
Created: 4/27/2018 12:00:00 AM
Last Editorial Review: 4/30/2018 12:00:00 AM




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Rock Climbing Goes Mainstream for Exercise Buffs

Title: Rock Climbing Goes Mainstream for Exercise Buffs
Category: Health News
Created: 5/1/2018 12:00:00 AM
Last Editorial Review: 5/1/2018 12:00:00 AM




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Skin's 'Good' Bacteria May Be Promising Weapon Against Eczema

Title: Skin's 'Good' Bacteria May Be Promising Weapon Against Eczema
Category: Health News
Created: 5/3/2018 12:00:00 AM
Last Editorial Review: 5/3/2018 12:00:00 AM




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After Trump Hypes Use of a Lupus Med Against COVID-19, Lupus Patients Face Shortages

Title: After Trump Hypes Use of a Lupus Med Against COVID-19, Lupus Patients Face Shortages
Category: Health News
Created: 4/25/2020 12:00:00 AM
Last Editorial Review: 4/27/2020 12:00:00 AM




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Breastfeeding May Help Guard Against Diabetes

Title: Breastfeeding May Help Guard Against Diabetes
Category: Health News
Created: 5/5/2020 12:00:00 AM
Last Editorial Review: 5/6/2020 12:00:00 AM




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Did the Movie 'Joker' Reinforce Prejudice Against Mentally Ill?

Title: Did the Movie 'Joker' Reinforce Prejudice Against Mentally Ill?
Category: Health News
Created: 4/27/2020 12:00:00 AM
Last Editorial Review: 4/28/2020 12:00:00 AM




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Religion Helps Protect Against 'Deaths of Despair': Study

Title: Religion Helps Protect Against 'Deaths of Despair': Study
Category: Health News
Created: 5/6/2020 12:00:00 AM
Last Editorial Review: 5/7/2020 12:00:00 AM




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Your Best Bet Against Heart Attack, Stroke? Lower Blood Pressure

Title: Your Best Bet Against Heart Attack, Stroke? Lower Blood Pressure
Category: Health News
Created: 2/20/2020 12:00:00 AM
Last Editorial Review: 2/21/2020 12:00:00 AM




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One Dose of HPV Vaccine May Protect Against Cervical Cancer

Title: One Dose of HPV Vaccine May Protect Against Cervical Cancer
Category: Health News
Created: 2/10/2020 12:00:00 AM
Last Editorial Review: 2/10/2020 12:00:00 AM




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Drug Offers Hope Against Tough-to-Treat Chronic Cough

Title: Drug Offers Hope Against Tough-to-Treat Chronic Cough
Category: Health News
Created: 2/26/2020 12:00:00 AM
Last Editorial Review: 2/26/2020 12:00:00 AM




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Magnetic Brain 'Zap' Shows Promise Against Severe Depression

Title: Magnetic Brain 'Zap' Shows Promise Against Severe Depression
Category: Health News
Created: 4/7/2020 12:00:00 AM
Last Editorial Review: 4/8/2020 12:00:00 AM




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A novel GPER antagonist protects against the formation of estrogen-induced cholesterol gallstones in female mice [Research Articles]

Many clinical studies and epidemiological investigations have clearly demonstrated that women are twice as likely to develop cholesterol gallstones as men, and oral contraceptives and other estrogen therapies dramatically increase that risk. Further, animal studies have revealed that estrogen promotes cholesterol gallstone formation through the estrogen receptor (ER) α, but not ERβ, pathway. More importantly, some genetic and pathophysiological studies have found that G protein-coupled estrogen receptor (GPER) 1 is a new gallstone gene, Lith18, on chromosome 5 in mice and produces additional lithogenic actions, working independently of ERα, to markedly increase cholelithogenesis in female mice. Based on computational modeling of GPER, a novel series of GPER-selective antagonists were designed, synthesized, and subsequently assessed for their therapeutic effects via calcium mobilization, cAMP, and ERα and ERβ fluorescence polarization binding assays. From this series of compounds, one new compound, 2-cyclohexyl-4-isopropyl-N-(4-methoxybenzyl)aniline (CIMBA), exhibits superior antagonism and selectivity exclusively for GPER. Furthermore, CIMBA reduces the formation of 17β-estradiol-induced gallstones in a dose-dependent manner in ovariectomized mice fed a lithogenic diet for 8 weeks. At 32 μg/day/kg CIMBA, no gallstones are found, even in ovariectomized ERα (–/–) mice treated with 6 μg/day 17β-estradiol and fed the lithogenic diet for 8 weeks. In conclusion, CIMBA treatment protects against the formation of estrogen-induced cholesterol gallstones by inhibiting the GPER signaling pathway in female mice. CIMBA may thus be a new agent for effectively treating cholesterol gallstone disease in women.­




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Barrier-to-Autointegration Factor 1 Protects against a Basal cGAS-STING Response

ABSTRACT

Although the pathogen recognition receptor pathways that activate cell-intrinsic antiviral responses are well delineated, less is known about how the host regulates this response to prevent sustained signaling and possible immune-mediated damage. Using a genome-wide CRISPR-Cas9 screening approach to identify host factors that modulate interferon-stimulated gene (ISG) expression, we identified the DNA binding protein Barrier-to-autointegration factor 1 (Banf1), a previously described inhibitor of retrovirus integration, as a modulator of basal cell-intrinsic immunity. Ablation of Banf1 by gene editing resulted in chromatin activation near host defense genes with associated increased expression of ISGs, including Oas2, Rsad2 (viperin), Ifit1, and ISG15. The phenotype in Banf1-deficient cells occurred through a cGAS-, STING-, and IRF3-dependent signaling axis, was associated with reduced infection of RNA and DNA viruses, and was reversed in Banf1 complemented cells. Confocal microscopy and biochemical studies revealed that a loss of Banf1 expression resulted in higher level of cytosolic double-stranded DNA at baseline. Our study identifies an undescribed role for Banf1 in regulating the levels of cytoplasmic DNA and cGAS-dependent ISG homeostasis and suggests possible therapeutic directions for promoting or inhibiting cell-intrinsic innate immune responses.

IMPORTANCE Although the interferon (IFN) signaling pathway is a key host mechanism to restrict infection of a diverse range of viral pathogens, its unrestrained activity either at baseline or in the context of an immune response can result in host cell damage and injury. Here, we used a genome-wide CRISPR-Cas9 screen and identified the DNA binding protein Barrier-to-autointegration factor 1 (Banf1) as a modulator of basal cell-intrinsic immunity. A loss of Banf1 expression resulted in higher level of cytosolic double-stranded DNA at baseline, which triggered IFN-stimulated gene expression via a cGAS-STING-IRF3 axis that did not require type I IFN or STAT1 signaling. Our experiments define a regulatory network in which Banf1 limits basal inflammation by preventing self DNA accumulation in the cytosol.




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Vaccine-Induced Th1-Type Response Protects against Invasive Group A Streptococcus Infection in the Absence of Opsonizing Antibodies

ABSTRACT

Recent global advocacy efforts have highlighted the importance of development of a vaccine against group A Streptococcus (GAS). Combo5 is a non-M protein-based vaccine that provides protection against GAS skin infection in mice and reduces the severity of pharyngitis in nonhuman primates. However, Combo5 with the addition of aluminum hydroxide (alum) as an adjuvant failed to protect against invasive GAS infection of mice. Here, we show that formulation of Combo5 with adjuvants containing saponin QS21 significantly improves protective efficacy, even though all 7 adjuvants tested generated high antigen-specific IgG antibody titers, including alum. Detailed characterization of Combo5 formulated with SMQ adjuvant, a squalene-in-water emulsion containing a TLR4 agonist and QS21, showed significant differences from the results obtained with alum in IgG subclasses generated following immunization, with an absence of GAS opsonizing antibodies. SMQ, but not alum, generated strong interleukin-6 (IL-6), gamma interferon (IFN-), and tumor necrosis alpha (TNF-α) responses. This work highlights the importance of adjuvant selection for non-M protein-based GAS vaccines to optimize immune responses and protective efficacy.

IMPORTANCE Availability of a group A Streptococcus vaccine remains an unmet public health need. Here, we tested different adjuvant formulations to improve the protective efficacy of non-M protein vaccine Combo5 in an invasive disease model. We show that novel adjuvants can dramatically shape the type of immune response developed following immunization with Combo5 and significantly improve protection. In addition, protection afforded by Combo5 is not mediated by opsonizing antibodies, believed to be the main correlate of protection against GAS infections. Overall, this report highlights the importance of adjuvant selection in raising protective immune responses against GAS invasive infection. Adjuvants that can provide a more balanced Th1/Th2-type response may be required to optimize protection of GAS vaccines, particularly those based on non-M protein antigens.




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Neutralizing Monoclonal Antibodies against the Gn and the Gc of the Andes Virus Glycoprotein Spike Complex Protect from Virus Challenge in a Preclinical Hamster Model

ABSTRACT

Hantaviruses are the etiological agent of hemorrhagic fever with renal syndrome (HFRS) and hantavirus cardiopulmonary syndrome (HCPS). The latter is associated with case fatality rates ranging from 30% to 50%. HCPS cases are rare, with approximately 300 recorded annually in the Americas. Recently, an HCPS outbreak of unprecedented size has been occurring in and around Epuyén, in the southwestern Argentinian state of Chubut. Since November of 2018, at least 29 cases have been laboratory confirmed, and human-to-human transmission is suspected. Despite posing a significant threat to public health, no treatment or vaccine is available for hantaviral disease. Here, we describe an effort to identify, characterize, and develop neutralizing and protective antibodies against the glycoprotein complex (Gn and Gc) of Andes virus (ANDV), the causative agent of the Epuyén outbreak. Using murine hybridoma technology, we generated 19 distinct monoclonal antibodies (MAbs) against ANDV GnGc. When tested for neutralization against a recombinant vesicular stomatitis virus expressing the Andes glycoprotein (GP) (VSV-ANDV), 12 MAbs showed potent neutralization and 8 showed activity in an antibody-dependent cellular cytotoxicity reporter assay. Escape mutant analysis revealed that neutralizing MAbs targeted both the Gn and the Gc. Four MAbs that bound different epitopes were selected for preclinical studies and were found to be 100% protective against lethality in a Syrian hamster model of ANDV infection. These data suggest the existence of a wide array of neutralizing antibody epitopes on hantavirus GnGc with unique properties and mechanisms of action.

IMPORTANCE Infections with New World hantaviruses are associated with high case fatality rates, and no specific vaccine or treatment options exist. Furthermore, the biology of the hantaviral GnGc complex, its antigenicity, and its fusion machinery are poorly understood. Protective monoclonal antibodies against GnGc have the potential to be developed into therapeutics against hantaviral disease and are also great tools to elucidate the biology of the glycoprotein complex.




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A Virus Hosted in Malaria-Infected Blood Protects against T Cell-Mediated Inflammatory Diseases by Impairing DC Function in a Type I IFN-Dependent Manner

ABSTRACT

Coinfections shape immunity and influence the development of inflammatory diseases, resulting in detrimental or beneficial outcome. Coinfections with concurrent Plasmodium species can alter malaria clinical evolution, and malaria infection itself can modulate autoimmune reactions. Yet, the underlying mechanisms remain ill defined. Here, we demonstrate that the protective effects of some rodent malaria strains on T cell-mediated inflammatory pathologies are due to an RNA virus cohosted in malaria-parasitized blood. We show that live and extracts of blood parasitized by Plasmodium berghei K173 or Plasmodium yoelii 17X YM, protect against P. berghei ANKA-induced experimental cerebral malaria (ECM) and myelin oligodendrocyte glycoprotein (MOG)/complete Freund’s adjuvant (CFA)-induced experimental autoimmune encephalomyelitis (EAE), and that protection is associated with a strong type I interferon (IFN-I) signature. We detected the presence of the RNA virus lactate dehydrogenase-elevating virus (LDV) in the protective Plasmodium stabilates and we established that LDV infection alone was necessary and sufficient to recapitulate the protective effects on ECM and EAE. In ECM, protection resulted from an IFN-I-mediated reduction in the abundance of splenic conventional dendritic cell and impairment of their ability to produce interleukin (IL)-12p70, leading to a decrease in pathogenic CD4+ Th1 responses. In EAE, LDV infection induced IFN-I-mediated abrogation of IL-23, thereby preventing the differentiation of granulocyte-macrophage colony-stimulating factor (GM-CSF)-producing encephalitogenic CD4+ T cells. Our work identifies a virus cohosted in several Plasmodium stabilates across the community and deciphers its major consequences on the host immune system. More generally, our data emphasize the importance of considering contemporaneous infections for the understanding of malaria-associated and autoimmune diseases.

IMPORTANCE Any infection modifies the host immune status, potentially ameliorating or aggravating the pathophysiology of a simultaneous inflammatory condition. In the course of investigating how malaria infection modulates the severity of contemporaneous inflammatory diseases, we identified a nonpathogenic mouse virus in stabilates of two widely used rodent parasite lines: Plasmodium berghei K173 and Plasmodium yoelii 17X YM. We established that the protective effects of these Plasmodium lines on cerebral malaria and multiple sclerosis are exclusively due to this virus. The virus induces a massive type I interferon (IFN-I) response and causes quantitative and qualitative defects in the ability of dendritic cells to promote pathogenic T cell responses. Beyond revealing a possible confounding factor in rodent malaria models, our work uncovers some bases by which a seemingly innocuous viral (co)infection profoundly changes the immunopathophysiology of inflammatory diseases.




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A Chimeric Japanese Encephalitis Vaccine Protects against Lethal Yellow Fever Virus Infection without Inducing Neutralizing Antibodies

ABSTRACT

Recent outbreaks of yellow fever virus (YFV) in West Africa and Brazil resulted in rapid depletion of global vaccine emergency stockpiles and raised concerns about being unprepared against future YFV epidemics. Here we report that a live attenuated virus similar to the Japanese encephalitis virus (JEV) vaccine JE-CVax/Imojev that consists of YFV-17D vaccine from which the structural (prM/E) genes have been replaced with those of the JEV SA14-14-2 vaccine strain confers full protection in mice against lethal YFV challenge. In contrast to the YFV-17D-mediated protection against YFV, this protection is not mediated by neutralizing antibodies but correlates with YFV-specific nonneutralizing antibodies and T cell responses against cell-associated YFV NS1 and other YFV nonstructural (NS) proteins. Our findings reveal the potential of YFV NS proteins to mediate protection and demonstrate that chimeric flavivirus vaccines, such as Imojev, could confer protection against two flaviviruses. This dual protection may have implications for the possible off-label use of JE-CVax in case of emergency and vaccine shortage during YFV outbreaks. In addition, populations in Asia that have been vaccinated with Imojev may already be protected against YFV should outbreaks ever occur on that continent, as several countries/regions in the Asia-Pacific are vulnerable to international spread of the YFV.

IMPORTANCE Efficient and safe vaccines against yellow fever (e.g., YFV-17D) that provide long-lasting protection by rapidly inducing neutralizing antibody responses exist. However, the vaccine supply cannot cope with an increasing demand posed by urban outbreaks in recent years. Here we report that JE-CVax/Imojev, a YFV-17D-based chimeric Japanese encephalitis vaccine, also efficiently protects against YFV infection in mice. In case of shortage of the YFV vaccine during yellow fever outbreaks, (off-label) use of JE-CVax/Imojev may be considered. Moreover, wider use of JE-CVax/Imojev in Asia may lower the risk of the much-feared YFV spillover to the continent. More generally, chimeric vaccines that combine surface antigens and replication machineries of two distinct flaviviruses may be considered dual vaccines for the latter pathogen without induction of surface-specific antibodies. Following this rationale, novel flavivirus vaccines that do not hold a risk for antibody-dependent enhancement (ADE) of infection (inherent to current dengue vaccines and dengue vaccine candidates) could be designed.




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Romo1-Derived Antimicrobial Peptide Is a New Antimicrobial Agent against Multidrug-Resistant Bacteria in a Murine Model of Sepsis

ABSTRACT

To overcome increasing bacterial resistance to conventional antibiotics, many antimicrobial peptides (AMPs) derived from host defense proteins have been developed. However, there are considerable obstacles to their application to systemic infections because of their low bioavailability. In the present study, we developed an AMP derived from Romo1 (AMPR-11) that exhibits a broad spectrum of antimicrobial activity. AMPR-11 showed remarkable efficacy against sepsis-causing bacteria, including multidrug-resistant strains, with low toxicity in a murine model of sepsis after intravenous administration. It seems that AMPR-11 disrupts bacterial membranes by interacting with cardiolipin and lipid A. From the results of this study, we suggest that AMPR-11 is a new class of agent for overcoming low efficacy in the intravenous application of AMPs and is a promising candidate to overcome multidrug resistance.

IMPORTANCE Abuse of antibiotics often leads to increase of multidrug-resistant (MDR) bacteria, which threatens the life of human beings. To overcome threat of antibiotic resistance, scientists are developing a novel class of antibiotics, antimicrobial peptides, that can eradicate MDR bacteria. Unfortunately, these antibiotics have mainly been developed to cure bacterial skin infections rather than others, such as life-threatening sepsis. Major pharmaceutical companies have tried to develop antiseptic drugs; however, they have not been successful. Here, we report that AMPR-11, the antimicrobial peptide (AMP) derived from mitochondrial nonselective channel Romo1, has antimicrobial activity against Gram-positive and Gram-negative bacteria comprising many clinically isolated MDR strains. Moreover, AMPR-11 increased the survival rate in a murine model of sepsis caused by MDR bacteria. We propose that AMPR-11 could be a novel antiseptic drug candidate with a broad antimicrobial spectrum to overcome MDR bacterial infection.




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Human Neutrophils Produce Antifungal Extracellular Vesicles against Aspergillus fumigatus

ABSTRACT

Polymorphonuclear granulocytes (PMNs) are indispensable for controlling life-threatening fungal infections. In addition to various effector mechanisms, PMNs also produce extracellular vesicles (EVs). Their contribution to antifungal defense has remained unexplored. We reveal that the clinically important human-pathogenic fungus Aspergillus fumigatus triggers PMNs to release a distinct set of antifungal EVs (afEVs). Proteome analyses indicated that afEVs are enriched in antimicrobial proteins. The cargo and the release kinetics of EVs are modulated by the fungal strain confronted. Tracking of afEVs indicated that they associated with fungal cells and even entered fungal hyphae, resulting in alterations in the morphology of the fungal cell wall and dose-dependent antifungal effects. To assess as a proof of concept whether the antimicrobial proteins found in afEVs might contribute to growth inhibition of hyphae when present in the fungal cytoplasm, two human proteins enriched in afEVs, cathepsin G and azurocidin, were heterologously expressed in fungal hyphae. This led to reduced fungal growth relative to that of a control strain producing the human retinol binding protein 7. In conclusion, extracellular vesicles produced by neutrophils in response to A. fumigatus infection are able to associate with the fungus, limit growth, and elicit cell damage by delivering antifungal cargo. This finding offers an intriguing, previously overlooked mechanism of antifungal defense against A. fumigatus.

IMPORTANCE Invasive fungal infections caused by the mold Aspergillus fumigatus are a growing concern in the clinic due to the increasing use of immunosuppressive therapies and increasing antifungal drug resistance. These infections result in high rates of mortality, as treatment and diagnostic options remain limited. In healthy individuals, neutrophilic granulocytes are critical for elimination of A. fumigatus from the host; however, the exact extracellular mechanism of neutrophil-mediated antifungal activity remains unresolved. Here, we present a mode of antifungal defense employed by human neutrophils against A. fumigatus not previously described. We found that extracellular vesicles produced by neutrophils in response to A. fumigatus infection are able to associate with the fungus, limit growth, and elicit cell damage by delivering antifungal cargo. In the end, antifungal extracellular vesicle biology provides a significant step forward in our understanding of A. fumigatus host pathogenesis and opens up novel diagnostic and therapeutic possibilities.




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APOBEC3C Tandem Domain Proteins Create Super Restriction Factors against HIV-1

ABSTRACT

Humans encode proteins, called restriction factors, that inhibit replication of viruses such as HIV-1. The members of one family of antiviral proteins, apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like 3 (APOBEC3; shortened here to A3), act by deaminating cytidines to uridines during the reverse transcription reaction of HIV-1. The A3 locus encodes seven genes, named A3A to A3H. These genes have either one or two cytidine deaminase domains, and several of these A3s potently restrict HIV-1. A3C, which has only a single cytidine deaminase domain, however, inhibits HIV-1 only very weakly. We tested novel double domain protein combinations by genetically linking two A3C genes to make a synthetic tandem domain protein. This protein created a "super restriction factor" that had more potent antiviral activity than the native A3C protein, which correlated with increased packaging into virions. Furthermore, disabling one of the active sites of the synthetic tandem domain protein resulted in an even greater increase in the antiviral activity—recapitulating a similar evolution seen in A3F and A3G (double domain A3s that use only a single catalytically active deaminase domain). These A3C tandem domain proteins do not have an increase in mutational activity but instead inhibit formation of reverse transcription products, which correlates with their ability to form large higher-order complexes in cells. Finally, the A3C-A3C super restriction factor largely escaped antagonism by the HIV-1 viral protein Vif.

IMPORTANCE As a part of the innate immune system, humans encode proteins that inhibit viruses such as HIV-1. These broadly acting antiviral proteins do not protect humans from viral infections because viruses encode proteins that antagonize the host antiviral proteins to evade the innate immune system. One such example of a host antiviral protein is APOBEC3C (A3C), which weakly inhibits HIV-1. Here, we show that we can improve the antiviral activity of A3C by duplicating the DNA sequence to create a synthetic tandem domain and, furthermore, that the proteins thus generated are relatively resistant to the viral antagonist Vif. Together, these data give insights about how nature has evolved a defense against viral pathogens such as HIV.




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Surfactant Protein-A Protects against IL-13-Induced Inflammation in Asthma [MUCOSAL IMMUNOLOGY]

Key Points

  • SP-A is a collectin and plays a key role in innate immunity in the lung.

  • SP-A modulates inflammation in airway epithelial cells from patients with asthma.

  • SP-A modulates IL-13–induced inflammation through downstream IL-6/STAT3 signaling.