scholarly journals Autophagy induction by thiostrepton improves the efficacy of immunogenic chemotherapy

2020 ◽  
Vol 8 (1) ◽  
pp. e000462 ◽  
Author(s):  
Yan Wang ◽  
Wei Xie ◽  
Juliette Humeau ◽  
Guo Chen ◽  
Peng Liu ◽  
...  
Keyword(s):  
Immune Responses ◽  
Atp Release ◽  
High Mobility ◽  
Fluorescent Biosensors ◽  
Adaptive Immune ◽  
Autophagy Induction ◽  
Screen Approach ◽  
Immunocompetent Mice ◽  
Do So

BackgroundImmunogenic cell death (ICD) is a peculiar modality of cellular demise that elicits adaptive immune responses and triggers T cell-dependent immunity.MethodsFluorescent biosensors were employed for an unbiased drug screen approach aiming at the identification of ICD enhancers.ResultsHere, we discovered thiostrepton as an enhancer of ICD able to boost chemotherapy-induced ATP release, calreticulin exposure and high-mobility group box 1 exodus. Moreover, thiostrepton enhanced anticancer immune responses of oxaliplatin (OXA) in vivo in immunocompetent mice, yet failed to do so in immunodeficient animals. Consistently, thiostrepton combined with OXA altered the ratio of cytotoxic T lymphocytes to regulatory T cells, thus overcoming immunosuppression and reinstating anticancer immunosurveillance.ConclusionAltogether, these results indicate that thiostrepton can be advantageously combined with chemotherapy to enhance anticancer immunogenicity.

scholarly journals Neutrophil subtypes shape HIV-specific CD8 T-cell responses after vaccinia virus infection

npj Vaccines ◽  
2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Mauro Di Pilato ◽  
Miguel Palomino-Segura ◽  
Ernesto Mejías-Pérez ◽  
Carmen E. Gómez ◽  
Andrea Rubio-Ponce ◽  
...  
Keyword(s):  
T Cell ◽  
Immune Responses ◽  
Vaccinia Virus ◽  
Adaptive Immune System ◽  
T Cell Responses ◽  
Cd8 T Cell ◽  
Cell Responses ◽  
Adaptive Immune

AbstractNeutrophils are innate immune cells involved in the elimination of pathogens and can also induce adaptive immune responses. Nα and Nβ neutrophils have been described with distinct in vitro capacity to generate antigen-specific CD8 T-cell responses. However, how these cell types exert their role in vivo and how manipulation of Nβ/Nα ratio influences vaccine-mediated immune responses are not known. In this study, we find that these neutrophil subtypes show distinct migratory and motility patterns and different ability to interact with CD8 T cells in the spleen following vaccinia virus (VACV) infection. Moreover, after analysis of adhesion, inflammatory, and migration markers, we observe that Nβ neutrophils overexpress the α4β1 integrin compared to Nα. Finally, by inhibiting α4β1 integrin, we increase the Nβ/Nα ratio and enhance CD8 T-cell responses to HIV VACV-delivered antigens. These findings provide significant advancements in the comprehension of neutrophil-based control of adaptive immune system and their relevance in vaccine design.

scholarly journals Impact of HMGB1/TLR Ligand Complexes on HIV-1 Replication: Possible Role for Flagellin during HIV-1 Infection

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Piotr Nowak ◽  
Samir Abdurahman ◽  
Annica Lindkvist ◽  
Marius Troseid ◽  
Anders Sönnerborg
Keyword(s):  
Immune Responses ◽  
Cpg Odn ◽  
Cell Necrosis ◽  
Adaptive Immune ◽  
Microbial Product ◽  
P24 Antigen ◽  
Culture Supernatants ◽  
Hiv 1

Objective. We hypothesized that HMGB1 in complex with bacterial components, such as flagellin, CpG-ODN, and LPS, promotes HIV-1 replication. Furthermore, we studied the levels of antiflagellin antibodies during HIV-1-infection.Methods. Chronically HIV-1-infected U1 cells were stimulated with necrotic extract/recombinant HMGB1 in complex with TLR ligands or alone. HIV-1 replication was estimated by p24 antigen in culture supernatants 48–72 hours after stimulation. The presence of systemic anti-flagellin IgG was determined in 51 HIV-1-infected patients and 19 controls by immunoblotting or in-house ELISA.Results. Flagellin, LPS, and CpG-ODN induced stronger HIV-1 replication when incubated together with necrotic extract or recombinant HMGB1 than activation by any of the compounds alone. Moreover, the stimulatory effect of necrotic extract was inhibited by depletion of HMGB1. Elevated levels of anti-flagellin antibodies were present in plasma from HIV-1-infected patients and significantly decreased during 2 years of antiretroviral therapy.Conclusions. Our findings implicate a possible role of HGMB1-bacterial complexes, as a consequence of microbial translocation and cell necrosis, for immune activation in HIV-1 pathogenesis. We propose that flagellin is an important microbial product, that modulates viral replication and induces adaptive immune responsesin vivo.

scholarly journals Dendritic Cells under Hypoxia: How Oxygen Shortage Affects the Linkage between Innate and Adaptive Immunity

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Sandra Winning ◽  
Joachim Fandrey
Keyword(s):  
Dendritic Cells ◽  
Immune Responses ◽  
Adaptive Immune Response ◽  
Mature Dendritic Cell ◽  
Innate And Adaptive Immunity ◽  
Cell Functions ◽  
Adaptive Immune ◽  
Oxygen Shortage

Dendritic cells (DCs) are considered as one of the main regulators of immune responses. They collect antigens, process them, and present typical antigenic structures to lymphocytes, thereby inducing an adaptive immune response. All these processes take place under conditions of oxygen shortage (hypoxia) which is often not considered in experimental settings. This review highlights how deeply hypoxia modulates human as well as mouse immature and mature dendritic cell functions. It tries to linkin vitroresults to actualin vivostudies and outlines how hypoxia-mediated shaping of dendritic cells affects the activation of (innate) immunity.

Immune responses to hapten conjugates in vitro

1975 ◽  
Vol 8 (4) ◽  
pp. 507-522
Author(s):  
Sirkka Kontiainen ◽  
O. Mäkelä ◽  
M. Hurme
Keyword(s):  
Tissue Culture ◽  
Immune Responses ◽  
Cell Types ◽  
Antibody Responses ◽  
Tissue Cultures ◽  
Cell Type ◽  
Animal Body ◽  
Do So

Several functions of the animal body can take place in cell or tissue cultures with almost unreduced efficiency and precision. Functions, where only one cell type is involved, often do so, but also some differentiation steps where interactions between two or more cell types are clearly needed can take place in tissue culture (Saxén et al. 1968).Most immune responses require collaboration between two or more cell types (Claman, Chaperon & Triplett, 1966; Miller & Mitchell, 1968; Feldmann & Nossal 1972c). Some of them can be easily induced in vitro but others cannot. Even when antibody responses can be induced in vitro their intensity varies a great deal. With some antigens and under some circumstances a response in vitro can be nearly as strong as one in vivo. A crude comparison can be derived from responses in vitro and in vivo to the same antigen, conjugate of hapten NIP and pneumococcal polysaccharide type III (NIP-SIll, Nakamura, Ray & Mäkelä, 1973).

scholarly journals A Pervasive Review on New Advancements of Nano Vaccines on Covid-19 Pandemic

2021 ◽  
Vol 70 (2) ◽  
Author(s):  
Ranajit Nath ◽  
Ambika Mandal ◽  
Ratul Bhowmik ◽  
Ratna Roy ◽  
Riya Biswas ◽  
...  
Keyword(s):  
Clinical Trials ◽  
Immune Responses ◽  
Viral Vector ◽  
Efficient Tool ◽  
Angiotensin Converting Enzyme 2 ◽  
Adaptive Immune ◽  
Successful Vaccine ◽  
Rapid Spread ◽  
Health Organization

The infection that causes COVID-19 may be a pathogen referred to as severe acute respiratory syndrome coronavirus-2 (SARS-CoV2) and is believed to possess originated from China's Wuhan Province. The rapid spread of coronavirus disease 2019 (COVID-19) has become a worldwide concern, with the planet Health Organization (WHO) declaring it an epidemic on March, 2020. To enter the cells, SARS-CoV-2 S requires angiotensin-converting enzyme 2 (ACE2). Many existing vaccines have drawbacks like insufficient system stimulation, in vivo instability, high toxicity, the need for a chilly chain, and multiple administration. A nanotechnology is an efficient tool for addressing these issues. A successful vaccine against SARS-CoV-2 infection is predicted to stimulate innate and adaptive immune responses and protects against severe sorts of coronavirus disease 2019 (COVID-19). Different strategies are introduced because the go after an efficient and safe vaccination has begun. Currently, the foremost common vaccine types studied in clinical trials include viral vector-based vaccinations, genetic vaccines, attenuated vaccines, and protein-based vaccines. during this review, we cover the foremost promising anti-COVID-19 vaccine clinical trials also as various vaccination strategies to shed more light on the continued clinical trials. it's also discussed how nanotechnology is often wont to better understand the pathology of the present pandemic, also as how our understanding of SARS-CoV-2 cellular uptake and toxicity can influence future nanotoxicological considerations and nanomedicine design of safe yet effective nanomaterials.

scholarly journals Ankylosis homologue mediates cellular efflux of ATP, not pyrophosphate

2021 ◽  
Author(s):  
Flora Szeri ◽  
Fatemeh Niaziorimi ◽  
Sylvia Donnelly ◽  
Nishat Fariha ◽  
Mariia Tertyshnaia ◽  
...  
Keyword(s):  
Culture Medium ◽  
Bone Matrix ◽  
Atp Release ◽  
Hek293 Cells ◽  
Wild Type ◽  
Plasma Membrane Protein ◽  
Mineralized Bone Matrix ◽  
Rule Out ◽  
Do So

AbstractThe plasma membrane protein Ankylosis Homologue (ANKH, mouse ortholog: Ank) prevents pathological mineralization of joints by controlling extracellular levels of the mineralization inhibitor pyrophosphate (PPi). It was long thought that ANKH acts by transporting PPi into the joints, but we recently showed that ANKH releases large amounts of nucleoside triphosphates (NTPs), predominantly ATP, into the culture medium. This ATP is converted extracellularly into PPi and AMP by the ectoenzyme Ectonucleotide Pyrophosphatase Phosphodiesterase 1 (ENPP1). We could not rule out, however, that cells also release PPi directly via ANK. We now addressed this question by determining the effect of a complete absence of ENPP1 on ANKH-dependent extracellular PPi concentrations. Introduction of ANKH in ENPP1-deficient HEK293 cells resulted in robust cellular ATP release without the concomitant increase in extracellular PPi seen in ENPP1-proficient cells.Ank-activity was previously shown to be responsible for about 75% of the PPi found in mouse bones. However, bones of Enpp1-/- mice contained < 2.5% of the PPi found in bones of wild type mice, showing that Enpp1-activity is also a prerequisite for Ank-dependent PPi incorporation into the mineralized bone matrix in vivo. Hence, ATP release precedes ENPP1-mediated PPi formation. We find that ANKH also provides about 25% of plasma PPi, whereas we have previously shown that 60-70 % of plasma PPi is derived from the NTPs extruded by the ABC transporter, ABCC6. Both transporters that keep plasma PPi at sufficient levels to prevent pathological calcification, therefore do so by extruding NTPs rather than PPi itself.

scholarly journals Role of Type I Interferons on Filovirus Pathogenesis

Vaccines ◽  
2019 ◽  
Vol 7 (1) ◽  
pp. 22 ◽  
Author(s):  
Beatriz Escudero-Pérez ◽  
César Muñoz-Fontela
Keyword(s):  
Animal Models ◽  
Immune Responses ◽  
Marburg Virus ◽  
Type I Interferons ◽  
Type I ◽  
Adaptive Immune ◽  
Antigen Presenting

Filoviruses, such as Ebola and Marburg virus, encode viral proteins with the ability to counteract the type I interferon (IFN-I) response. These IFN-I antagonist proteins are crucial to ensure virus replication, prevent an antiviral state in infected and bystander cells, and impair the ability of antigen-presenting cells to initiate adaptive immune responses. However, in recent years, a number of studies have underscored the conflicting data between in vitro studies and in vivo data obtained in animal models and clinical studies during outbreaks. This review aims to summarize these data and to discuss the relative contributions of IFN-α and IFN-β to filovirus pathogenesis in animal models and humans. Finally, we evaluate the putative utilization of IFN-I in post-exposure therapy and its implications as a biomarker of vaccine efficacy.

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