Little is known about the composition and functional differences between extracellular vesicle (EV) subsets, such as microvesicles (MVs) and exosomes (EXOs), nor to what extent their cargo reflects the phenotypic state of the cell of origin. Brain endothelial cells are the constitutive part of the blood–brain barrier (BBB), a selective barrier that maintains brain homeostasis. BBB impairment is associated with several neuroinflammatory diseases with the pro-inflammatory cytokine tumour necrosis factor (TNF) often playing a key role. In the present study, shotgun proteomics and parallel reaction monitoring (PRM)-based targeted mass spectrometry were used to characterise brain endothelial cell-released EVs, and to study how TNF exposure modulated EV protein cargoes. MVs were found to be enriched in mitochondrial and cytoskeletal proteins, whereas EXOs were enriched in adhesion, histone and ribosomal proteins. After stimulation with TNF, several proteins involved in TNF and NF-κB signalling pathways, that were found to be differentially expressed in cells, were also differentially expressed in both MVs and EXOs. Thus, our results revealed some novel proteins as potentially useful candidates for discriminating between MVs and EXOs, together with additional evidence that cells “package” proteins in EVs systematically and according to their phenotypic state.

BackgroundAstrocytes are the most abundant cells in the central nervous system and are responsible for a wide range of functions critical to normal neuronal development, synapse formation, blood-brain barrier regulation, and brain homeostasis. They are also actively involved in initiating and perpetuating neuroinflammatory responses. However, information about their proteomic phenotypes under inflammation is currently limited.MethodData-independent acquisition mass spectrometry was applied to extensively characterize the profile of more than 4000 proteins in immortalized human fetal astrocytes under distinct inflammatory conditions induced by TNF, IL-1β, and LPS, while multiplex immunoassay-based screening was used to quantify a wide range of cytokines released under these inflammatory conditions. Then, immunocytochemistry and western blotting were used to verify the activation of canonical and non-canonical NF-κB upon exposure to the different stimuli. Finally, an in vitro model of the blood-brain barrier consisting of a co-culture of primary human brain microvascular endothelial cells and primary human astrocytes was used to verify the inflammatory response of astrocytes upon LPS exposure in a more complex in vitro system.ResultsWe reported on a set of 186 proteins whose levels were significantly modulated by TNF, IL-1β, and LPS. These three stimuli induced proteome perturbations, which led to an increased abundance of key inflammatory proteins involved in antigen presentation and non-canonical NF-κB pathways. TNF and IL-1β, but not LPS, also activated the canonical NF-κB pathway, which in turn led to an extensive inflammatory response and dysregulation of cytoskeletal and adhesion proteins. In addition, TNF and LPS, but not IL-1β, increased the abundance of several interferon-stimulated gene products. Finally, TNF and IL-1β similarly upregulated the secretion of several cytokines and chemokines, whereas LPS only induced a moderate increase in IL-8, IFN-γ, and IL-1β secretion. Upregulation of proteins associated with type I IFN and non-canonical NF-κB signaling was also observed in primary astrocytes co-cultured with primary brain microvascular endothelial cells exposed to LPS.ConclusionsThe present study provides comprehensive information about the proteomic phenotypes of human astrocytes upon exposure to inflammatory stimuli both in monoculture and in co-culture with human brain microvascular endothelial cells.Electronic supplementary materialThe online version of this article (10.1186/s12974-018-1371-6) contains supplementary material, which is available to authorized users.

Medical use of opioids is essential to treat acute postoperative pain and for different types of chronic pain conditions. However, opioid therapies are associated with complex side effects that are challenging to manage. Long-term use often leads to tolerance, resulting in undertreatment of pain, difficulties estimating a safe dose escalation, and increased risk for overdose. Opioid therapy can also cause opioid-induced hyperalgesia (OIH), a paradoxical painful condition state where patients experience diffused increased sensitivity to pain, often unrelated to the original pain (Lee, Silverman, Hansen, Patel, & Manchikanti, 2011). The opioid epidemic, caused by over-prescription, continues to increase numbers of patients addicted to opioids, as well as users transitioning to heroin and other drugs (Blanco & Volkow, 2019). It is estimated that more than hundred deaths every day in the United States are caused by misuse or opioid overdose (Hser et al., 2019). Although it is generally assumed that physiological homeostatic adaptations cause these side effects, little is known about their underlying molecular and cellular mechanisms.Inside the body, morphine is metabolized into the two main active metabolites morphine-3-glucuronide (M3G) and morphine-6glucuronide (M6G). M6G is found at lower plasma concentration than M3G, but has much higher analgesic potency than M3G ( 200

Human African trypanosomiasis (HAT) caused by the extracellular protozoon Trypanosoma brucei, is a neglected tropical disease affecting the poorest communities in sub-Saharan Africa. HAT progresses from a hemolymphatic first stage (S1) to a meningo-encephalitic late stage (S2) when parasites reach the central nervous system (CNS), although the existence of an intermediate stage (Int.) has also been proposed. The pathophysiological mechanisms associated with the development of S2 encephalopathy are yet to be fully elucidated. Here we hypothesized that HAT progression toward S2 might be accompanied by an increased release of microvesicles (MVs), sub-micron elements (0.1–1 μm) involved in inflammatory processes and in the determination of the outcome of infections. We studied the morphology of MVs isolated from HAT cerebrospinal fluid (CSF) by transmission electron microscopy (TEM) and used flow cytometry to show that total-MVs and leukocyte derived-CD45+ MVs are significantly increased in concentration in S2 patients' CSF compared to S1 and Int. samples (n = 12 per group). To assess potential biological properties of these MVs, immortalized human astrocytes were exposed, in vitro, to MVs enriched from S1, Int. or S2 CSF. Data-independent acquisition mass spectrometry analyses showed that S2 MVs induced, compared to Int. or S1 MVs, a strong proteome modulation in astrocytes that resembled the one produced by IFN-γ, a key molecule in HAT pathogenesis. Our results indicate that HAT S2 CSF harbors MVs potentially involved in the mechanisms of pathology associated with HAT late stage. Such vesicles might thus represent a new player to consider in future functional studies.

background: SV-BR-1-GM, derived from a patient with grade 2 (moderately differentiated) breast cancer, is a GM-CSF-secreting breast cancer cell line with properties of antigen-presenting cells. SV-BR-1-GM and next-generation versions are covered by several pending and granted patents. Methods: We report findings from an open-label phase I, single-arm pilot study with irradiated SV-BR-1-GM cells in 3 breast and 1 ovarian cancer subjects. Inoculations were preceded by low-dose intravenous cyclophosphamide and followed by interferon-alpha2b injections into the SV-BR-1-GM inoculation sites. We assessed both cellular and humoral immune responses, and measured expression levels of SV-BR-1-GM HLA alleles. Results: Treatment was generally safe and well tolerated. Immune responses were elicited universally. Overall survival was more than 33 months for three of the four patients. As previously reported, one patient had prompt regression of metastases in lung, breast and soft tissue. Following cessation of treatment, the patient relapsed widely, including in the brain. Upon retreatment rapid tumor response was again seen, including complete regression of brain metastases. Consistent with a role of Class II HLA in contributing to SV-BR-1-GM’s mechanism of action, this patient allele-matched SV-BR-1-GM at the HLA-DRB1 and HLA-DRB3 loci. We are in the process of developing next-generation SV-BR-1-GM, expressing patient-specific HLAs. Patent applications were filed in various jurisdictions. Thus far, one is granted, in Japan. Conclusion: A whole-cell immunotherapy regimen with SV-BR-1-GM cells induced regression of metastatic breast cancer. We develop intellectual property based on SV-BR-1-GM’s predicted mechanism of action to develop additional whole-cell immunotherapies for cancer patients.