Search results for " Immune system"

Combined B, T and NK Cell Deficiency Accelerates Atherosclerosis in BALB/c Mice.

2016

This study focused on the unique properties of both the Ldlr knockout defect (closely mimicking the human situation) and the BALB/c (C) inbred mouse strain (Th-2 slanted immune response). We generated two immunodeficient strains with severe combined B- and T-cell immunodeficiency with or without a complete lack of natural killer cells to revisit the role of adaptive immune responses on atherogenesis. C-Ldlr-/- Rag1-/- mice, which show severe combined B- and T-cell immunodeficiency and C-Ldlr-/- Rag1-/- Il2rg-/- mice, which combine the T- and B-cell defect with a complete lack of natural killer cells and inactivation of multiple cytokine signalling pathways were fed an atherogenic Western ty…

Activation and selective IL-17 response of human Vγ9Vδ2 T lymphocytes by TLR-activated plasmacytoid dendritic cells.

2016

// Elena Lo Presti 1,2 , Nadia Caccamo 1,2 , Valentina Orlando 1,2 , Francesco Dieli 1,2 and Serena Meraviglia 1,2 1 Central Laboratory of Advanced Diagnosis and Biomedical Research (CLADIBIOR), University of Palermo, Palermo, Italy 2 Department of Biopathology and Medical Biotechnologies (DIBIMED), University of Palermo, Palermo, Italy Correspondence to: Serena Meraviglia, email: // Keywords : γδ T cells, plasmacytoid dendritic cells, IL-17, TLR activation, proliferation, Immunology and Microbiology Section, Immune response, Immunity Received : July 20, 2016 Accepted : August 02, 2016 Published :August 31, 2016 Abstract Vγ9Vδ2 T cells and plasmacytoid dendritic cells (pDCs) are two distinc…

2017

Bruton's tyrosine kinase (BTK) was initially discovered as a critical mediator of B cell receptor signaling in the development and functioning of adaptive immunity. Growing evidence also suggests multiple roles for BTK in mononuclear cells of the innate immune system, especially in dendritic cells and macrophages. For example, BTK has been shown to function in Toll-like receptor-mediated recognition of infectious agents, cellular maturation and recruitment processes, and Fc receptor signaling. Most recently, BTK was additionally identified as a direct regulator of a key innate inflammatory machinery, the NLRP3 inflammasome. BTK has thus attracted interest not only for gaining a more thoroug…

2020

Dendritic cells (DC) play a key role in the adaptive immune response due to their ability to present antigens and stimulate naive T cells. Many bacteria and viruses can efficiently target DC, resulting in impairment of their immunostimulatory function or elimination. Hence, the DC compartment requires replenishment following infection to ensure continued operational readiness of the adaptive immune system. Here, we investigated the molecular and cellular mechanisms of inflammation-induced DC generation. We found that infection with viral and bacterial pathogens as well as Toll-like receptor 9 (TLR9) ligation with CpG-oligodeoxynucleotide (CpG-ODN) expanded an erythropoietin (EPO)-dependent …

Topoisomerase 1 inhibition suppresses inflammatory genes and protects from death by inflammation

2015

Unwinding DNA and unleasing inflammation Fighting infections often comes with collateral damage, which sometimes can be deadly. For instance, in septic shock, the overwhelming release of inflammatory mediators drives multi-organ failure. Rialdi et al. now report a potential new therapeutic target for controlling excessive inflammation: the DNA unwinding enzyme topoisomerase I (Top1) (see the Perspective by Pope and Medzhitov). Upon infection, Top1 specifically localizes to the promoters of pathogen-induced genes and promotes their transcription by helping to recruit RNA polymerase II. Pharmacological inhibition of Top1 in a therapeutic setting increased survival in several mouse models of s…

Vitamin D3 affects innate immune status of European sea bass (Dicentrarchus labrax L.)

2017

The effects of vitamin D3 dietary administration on certain innate immune parameters on the expression of immune-related genes in head-kidney (HK) and gut were investigated in European sea bass Dicentrarchus labrax. Vitamin D3 (vD3) was orally administered to fish in a commercial pellet food supplemented with 0 (control); 3750; 18,750; or 37,500 U kg−1. Furthermore, gut histology was considered. This study showed a modulation in the activities examined in fish fed with the addition of vD3. After just 2 weeks of administration, diet supplementation with the vitamin resulted in increased phagocytic ability, while serum peroxidase content was increased in fish fed with all experimental diets a…

Enzymatic Activity of HPGD in Treg Cells Suppresses Tconv Cells to Maintain Adipose Tissue Homeostasis and Prevent Metabolic Dysfunction.

2019

Summary Regulatory T cells (Treg cells) are important for preventing autoimmunity and maintaining tissue homeostasis, but whether Treg cells can adopt tissue- or immune-context-specific suppressive mechanisms is unclear. Here, we found that the enzyme hydroxyprostaglandin dehydrogenase (HPGD), which catabolizes prostaglandin E2 (PGE2) into the metabolite 15-keto PGE2, was highly expressed in Treg cells, particularly those in visceral adipose tissue (VAT). Nuclear receptor peroxisome proliferator-activated receptor-γ (PPARγ)-induced HPGD expression in VAT Treg cells, and consequential Treg-cell-mediated generation of 15-keto PGE2 suppressed conventional T cell activation and proliferation. C…

Food quality affects the expression of antimicrobial peptide genes upon simulated parasite attack in the larvae of greater wax moth

2017

Predator‐prey interactions are an important evolutionary force affecting the immunity of the prey. Parasitoids and mites pierce the cuticle of their prey, which respond by activating their immune system against predatory attacks. Immunity is a costly function for the organism, as it often competes with other life‐history traits for limited nutrients. We tested whether the expression of antimicrobial peptides (AMP) of the larvae of the greater wax moth Galleria mellonella (L.) (Lepidoptera: Pyralidae) changes as a consequence of insertion of a nylon monofilament, which acts like a synthetic parasite. The treatment was done for larvae grown on a high‐quality vs. a low‐quality diet. The expres…

Silencing of Foxp3 enhances the antitumor efficacy of GM-CSF genetically modified tumor cell vaccine against B16 melanoma

2017

Antonio Miguel,1 Luis Sendra,1 Verónica Noé,2 Carles J Ciudad,2 Francisco Dasí,3,4 David Hervas,5 María José Herrero,1,6 Salvador F Aliño17 1Department of Pharmacology, Faculty of Medicine, University of Valencia, 2Department of Biochemistry and Molecular Biology, Faculty of Pharmacy, University of Barcelona, 3Research University Hospital of Valencia, INCLIVA Health Research Institute, 4Department of Physiology, Faculty of Medicine, University of Valencia Foundation, 5Biostatistics Unit, 6Pharmacogenetics Unit, Instituto de Investigación Sanitaria La Fe (IIS La Fe), 7Clinical Pharmacology Unit, ACM Hospital Univers…

2016

Immunologically, active visceral leishmaniasis (VL) is characterised by profound immunosuppression, severe systemic inflammatory responses and an impaired capacity to control parasite replication. Neutrophils are highly versatile cells, which play a crucial role in the induction as well as the resolution of inflammation, the control of pathogen replication and the regulation of immune responses. Neutrophil functions have been investigated in human cutaneous leishmaniasis, however, their role in human visceral leishmaniasis is poorly understood. In the present study we evaluated the activation status and effector functions of neutrophils in patients with active VL and after successful anti-l…