Exosomes are nano-sized membrane vesicles released from a wide variety of cells, formed in endosomes by inward budding of the endosomal limiting membrane. They have immune stimulatory-, inhibitory-, or tolerance-inducing effects, depending on their cellular origin, which is why they are investigated for use in vaccine and immune therapeutic strategies. In this study, we explored whether exosomes of different origins and functions can selectively target different immune cells in human peripheral blood.
View Article and Find Full Text PDFHuman in vitro generated dendritic cells and the exosomes they release are potential tools for the modulation of immune responses. Here, we characterized differently generated monocyte-derived dendritic cells (MDDCs) and their exosomes. Culturing of peripheral CD14+ cells from the same individuals with either interleukin (IL)-4 and granulocyte-macrophage colony-stimulating factor (GM-CSF) (conventional MDDCs) or alternatively with IL-4 and IL-3 generated immature MDDCs in 7 days.
View Article and Find Full Text PDFBackground: Exosomes are vesicles of 30 to 100 nm produced by inward budding of endosomal compartments and are released by a range of different cell types. Exosomes from antigen-presenting cells carry immunorelevant molecules like MHC class I and II and costimulatory molecules and thus are suggested to have a role in immune modulation.
Objective: To investigate the role of antigen-presenting cell derived exosomes in allergen presentation and T-cell stimulation.
Breast milk is a complex liquid with immune-competent cells and soluble proteins that provide immunity to the infant and affect the maturation of the infant's immune system. Exosomes are nanovesicles (30-100 nm) with an endosome-derived limiting membrane secreted by a diverse range of cell types. Because exosomes carry immunorelevant structures, they are suggested to participate in directing the immune response.
View Article and Find Full Text PDFWe investigated the effect of spherical gold nanoparticles on immature dendritic cells (DCs). Conventionally produced nanoparticles had a maturating effect on the DCs--a result of lipopolysaccharide (LPS) contamination. By modification of the production process, low-LPS particles were obtained, which had practically no effect on phenotypic maturation or cytokine production of the DCs.
View Article and Find Full Text PDFExosomes from APC are nano-vesicles that can induce antigen-specific T cell responses and are presently explored as therapeutic tools in different clinical settings. Investigations of the capacity of exosomes to stimulate T cells in vitro have mostly been performed on T cell hybridomas, clones or lines. Whether exosomes can stimulate T cells directly or need the presence of dendritic cells (DC) is debated.
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