Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences
This paper presents a review of recent work on the role that two epigenetic-related systems may play in information processing mechanisms in the brain. The first consists of exosomes that transport epigenetic-related molecules between neurons. The second consists of homeoproteins like Otx2 that carry information from sense organs to primary sensory cortex. There is developing evidence that presynaptic neurons may be able to modulate the fine microanatomical structure in the postsynaptic neuron.
International Journal of Cancer. Journal International Du Cancer
Myeloid-derived suppressor cells (MDSCs) promote tumor progression. The mechanisms of MDSC development during tumor growth remain unknown. Tumor exosomes (T-exosomes) have been implicated to play a role in immune regulation, however the role of exosomes in the induction of MDSCs is unclear. Our previous work demonstrated that exosomes isolated from tumor cells are taken up by bone marrow myeloid cells. Here, we extend those findings showing that exosomes isolated from T-exosomes switch the differentiation pathway of these myeloid cells to the MDSC pathway (CD11b(+)Gr-1(+)).
Ubiquitinated endosomal proteins that are deposited into the lumens of multivesicular bodies are either sorted for lysosomal-mediated degradation or secreted as exosomes into the extracellular milieu. The mechanisms that underlie the sorting of cellular cargo proteins are currently unknown. In this study, we show that the COP9 signalosome (CSN)-associated protein CSN5 quantitatively regulated proteins that were sorted into exosomes.
Exosomes represent a discrete population of vesicles that are secreted from various cell types to the extracellular media. Their protein and lipid composition are a consequence of sorting events at the level of the multivesicular body, a central organelle which integrates endocytic and secretory pathways. Characterization of exosomes from different biological samples has shown the presence of common as well as cell-type specific proteins. Remarkably, the protein content of the exosomes is modified upon pathological or stress conditions.
OBJECTIVE: We sought to determine whether exosome-like vesicles (ELVs) released from adipose tissue play a role in activation of macrophages and subsequent development of insulin resistance in a mouse model. RESEARCH DESIGN AND METHODS: ELVs released from adipose tissue were purified by sucrose gradient centrifugation and labeled with green fluorescent dye and then intravenously injected into B6 ob/ob mice (obese model) or B6 mice fed a high-fat diet.
IMPORTANCE OF THE FIELD: Liver is the major body reservoir for enzymes involved in the metabolism of endogenous and xenobiotic compounds. Recently, it has been shown that hepatocytes release exosome-like vesicles to the extracellular medium, and the proteomic characterization of these hepatocyte-secreted exosomes has revealed the presence of several of these enzymes on them.
In this study we observed that mice pretreated with tumor exosomes had a significant acceleration of tumor metastasis in the lung. Tumor metastasis correlated significantly with an increase in recruitment of more Myeloid-derived suppressor cells (MDSCs) in the lung of C57BL/6j (B6) mice pretreated with tumor exosomes. These effects were blunted when MyD88 knockout (KO) mice were pretreated with tumor exosomes.
PURPOSE: There is a compelling clinical imperative to identify discerning molecular biomarkers of hepatic disease in order to inform the diagnosis, prognosis and treatment. EXPERIMENTAL DESIGN: We have investigated the proteome of urinary vesicles present in urine samples obtained from experimental models for the study of liver injury, as an approach for identifying potential biomarkers for hepatic disease.
Molecular Therapy: The Journal of the American Society of Gene Therapy
Monocyte-derived myeloid cells play vital roles in inflammation-related autoimmune/inflammatory diseases and cancers. Here, we report that exosomes can deliver anti-inflammatory agents, such as curcumin, to activated myeloid cells in vivo. This technology provides a means for anti-inflammatory drugs, such as curcumin, to target the inflammatory cells as well as to overcome unwanted off-target effects that limit their utility. Using exosomes as a delivery vehicle, we provide evidence that curcumin delivered by exosomes is more stable and more highly concentrated in the blood.
Exosomes released from tumor cells having been shown to induce interleukin-6 release from myeloid-derived suppressor cells in a Toll-like receptor 2/Stat3-dependent manner. In this study, we show that exosomes released from tumor cells re-isolated from syngeneic mice are capable of inducing interleukin-6 in a Toll-like receptor 2-independent manner, whereas the data generated from exosomes of tumor cells having undergone numerous in vitro passages induce interleukin-6 in a Toll-like receptor 2-dependent manner.