Search results for "Acellular"

Modulation of Intracellular O-2 Concentration in Escherichia coli Strains Using Oxygen Consuming Devices

2018

International audience; The use of cell factories for the production of bulk and value-added compounds is nowadays an advantageous alternative to the traditional petrochemical methods. Nevertheless, the efficiency and productivity of several of these processes can improve with the implementation of micro-oxic or anoxic conditions. In the industrial setting, laccases are appealing catalysts that can oxidize a wide range of substrates and reduce O-2 to H2O. In this work, several laccase-based devices were designed and constructed to modulate the intracellular oxygen concentration in bacterial chassis. These oxygen consuming devices (OCDs) included Escherichia coil's native laccase (CueO) and …

The Challenging Riddle about the Janus-Type Role of Hsp60 and Related Extracellular Vesicles and miRNAs in Carcinogenesis and the Promises of Its Sol…

2021

Hsp60 is one of the most ancient and evolutionarily conserved members of the chaperoning system. It typically resides within mitochondria, in which it contributes to maintaining the organelle’s proteome integrity and homeostasis. In the last few years, it has been shown that Hsp60 also occurs in other locations, intracellularly and extracellularly, including cytosol, plasma-cell membrane, and extracellular vesicles (EVs). Consequently, non-canonical functions and interacting partners of Hsp60 have been identified and it has been realized that it is a hub molecule in diverse networks and pathways and that it is implicated, directly or indirectly, in the development of various pathological co…

Isolation and Analysis of Fasciola hepatica Extracellular Vesicles

2020

The finding of extracellular vesicles (EVs) as important players in parasite-parasite and host-parasite communications has led to an increasing number of reports in the literature. Different protocols have been developed for isolation and further characterization of EVs from parasitic helminths. In this chapter, we describe step by step procedures to isolate EVs secreted by Fasciola hepatica adults in culture, which could be also applied for other developmental stages of the parasite, as well as EVs present in plasma and urine. Along with classical isolation methods like differential ultracentrifugation, and more recent techniques like size exclusion chromatography (SEC), here we also refer…

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…

Cytomics of Oxidative Stress: Probes and Problems

2017

Oxidative stress has been implicated in cellular senescence and aging, as well as in the onset and progression of many diverse genetic and acquired diseases and conditions. However, reactive oxygen (ROS) and nitrogen (RNS) species initiating oxidative stress also serve important regulatory roles, mediated by intercellular and intracellular signaling, adaptation to endogenous and exogenous stress, and destruction of invading pathogens. Fluorescence-based analysis of oxidative stress and related processes is an important cytomic application; almost 4000 papers were published between 1989 and 2016. To ascertain the specific role of ROS and RNS in oxidative stress studies by cytomic methodologi…

Dimethyl fumarate alters intracellular Ca2+ handling in immune cells by redox-mediated pleiotropic effects

2019

Dimethyl fumarate (DMF) is widely used to treat the human autoimmune diseases multiple sclerosis (MS) and psoriasis. DMF causes short-term oxidative stress and activates the antioxidant response via the transcription factor Nrf2 but its immunosuppressive effect is not well understood. Immune cell activation depends on calcium signaling which itself is influenced by the cellular redox state. We therefore measured calcium, reactive oxygen species levels and glutathione content in lymphocytes from immunized mice before onset of experimental autoimmune encephalomyelitis, in peripheral blood mononuclear cells from MS patients treated with DMF, and in mouse splenocytes treated ex vivo with DMF. T…

The role of Ca(2+) in cell death caused by oxidative glutamate toxicity and ferroptosis

2018

Ca(2+) ions play a fundamental role in cell death mediated by oxidative glutamate toxicity or oxytosis, a form of programmed cell death similar and possibly identical to other forms of cell death like ferroptosis. Ca(2+) influx from the extracellular space occurs late in a cascade characterized by depletion of the intracellular antioxidant glutathione, increases in cytosolic reactive oxygen species and mitochondrial dysfunction. Here, we aim to compare oxidative glutamate toxicity with ferroptosis, address the signaling pathways that culminate in Ca(2+) influx and cell death and discuss the proteins that mediate this. Recent evidence hints toward a role of the machinery responsible for stor…

Preliminary evidence of the horizontal transmission of Wolbachia between Crioceris leaf beetles (Coleoptera: Chrysomelidae) and their Asparagus host …

2017

Intracellular bacteria of the genus Wolbachia (alpha-Proteobacteria) are the most widespread endosymbionts of insects. Host infection is usually associated with alterations in reproduction, such as cytoplasmic incompatibility, the induction of parthenogenesis and offspring sex ratio bias: all phenomena that may influence host speciation. In the present study, by using well-established molecular tools, we investigated the presence of Wolbachia in leaf beetles of the genus Crioceris and their host plants, which are various species of Asparagus. Multilocus sequence typing of bacterial genes showed that despite their occurrence in the same habitat and feeding on the same plant, two species of C…

Mesoglea Extracellular Matrix Reorganization during Regenerative Process in Anemonia viridis (Forskål, 1775)

2021

Given the anatomical simplicity and the extraordinary ability to regenerate missing parts of the body, Cnidaria represent an excellent model for the study of the mechanisms regulating regenerative processes. They possess the mesoglea, an amorphous and practically acellular extracellular matrix (ECM) located between the epidermis and the gastrodermis of the body and tentacles and consists of the same molecules present in the ECM of vertebrates, such as collagen, laminin, fibronectin and proteoglycans. This feature makes cnidarians anthozoans valid models for understanding the ECM role during regenerative processes. Indeed, it is now clear that its role in animal tissues is not just tissue su…

Engineering of Human Skeletal Muscle With an Autologous Deposited Extracellular Matrix

2018

Adult skeletal muscle progenitor cells can be embedded in an extracellular matrix (ECM) and tissue-engineered to form bio-artificial muscles (BAMs), composed of aligned post-mitotic myofibers. The ECM proteins which have been used most commonly are collagen type I and fibrin. Fibrin allows for in vitro vasculogenesis, however, high concentrations of fibrinolysis inhibitors are needed to inhibit degradation of the ECM and subsequent loss of BAM tissue structure. For in vivo implantation, fibrinolysis inhibition may prove difficult or even harmful to the host. Therefore, we adapted in vitro culture conditions to enhance the deposition of de novo synthesized collagen type I gradually replacing…