Transmissible Endosomal Intoxication: A Balance between Exosomes and Lysosomes at the Basis of Intercellular Amyloid Propagation.

In Alzheimer's disease (AD), endolysosomal dysfunctions are amongst the earliest cellular features to appear. Each organelle of the endolysosomal system, from the multivesicular body (MVB) to the lysosome, contributes to the homeostasis of amyloid precursor protein (APP) cleavage products including β-amyloid (Aβ) peptides. Hence, this review will attempt to disentangle how changes in the endolysosomal system cumulate to the generation of toxic amyloid species and hamper their degradation.

Immunomodulatory role for membrane vesicles released by THP-1 macrophages and respiratory pathogens during macrophage infection.

Background: During infection, inflammation is partially driven by the release of mediators which facilitate intercellular communication. Amongst these mediators are small membrane vesicles (MVs) that can be released by both host cells and Gram-negative and -positive bacteria. Bacterial membrane vesicles are known to exert immuno-modulatory and -stimulatory actions.

Budesonide, fluticasone propionate, and azithromycin do not modulate the membrane vesicle release by THP-1 macrophages and respiratory pathogens during macrophage infection.

Patients with more severe chronic obstructive pulmonary disease frequently experience exacerbations and it is estimated that up to 50% of these exacerbations are associated with bacterial infections. The mainstay treatment for these infection-related exacerbations constitutes the administration of glucocorticoids, alone or in combination with antibiotics. A recent line of evidence demonstrates that many hormones including the steroid beclomethasone can also directly affect bacterial growth, virulence, and antibiotic resistance.

Bead-based flow-cytometry for semi-quantitative analysis of complex membrane vesicle populations released by bacteria and host cells.

During infection, the release of nano-sized membrane vesicle is a process which is common both for bacteria and host cells. Host cell-derived membrane vesicles can be involved in innate and adaptive immunity whereas bacterial membrane vesicles can contribute to bacterial pathogenicity. To study the contribution of both membrane vesicle populations during infection is highly complicated as most vesicles fall within a similar size range of 30-300nm.

Effects of N-acetyl-L-cysteine on the membrane vesicle release and growth of respiratory pathogens.

Bacterial infections contribute to the disease progression of chronic obstructive pulmonary disease by stimulating mucus production in the airways. This increased mucus production and other symptoms are often alleviated when patients are treated with mucolytics such as N-acetyl-L-cysteine (NAC). Moreover, NAC has been suggested to inhibit bacterial growth.

Cigarette smoke extract induced exosome release is mediated by depletion of exofacial thiols and can be inhibited by thiol-antioxidants.

Introduction: Airway epithelial cells have been described to release extracellular vesicles (EVs) with pathological properties when exposed to cigarette smoke extract (CSE). As CSE causes oxidative stress, we investigated whether its oxidative components are responsible for inducing EV release and whether this could be prevented using the thiol antioxidants N-acetyl-l-cysteine (NAC) or glutathione (GSH).

Methods: BEAS-2B cells were exposed for 24h to CSE, HO, acrolein, 5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB), bacitracin, rutin or the anti-protein disulfide isomerase (PDI) antibody clone RL90; with or without NAC or GSH.