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Human thymic epithelial primary cells produce exosomes carrying tissue-restricted antigens.

ABSTRACT: Exosomes are nano-sized vesicles released by cells into the extracellular space and have been shown to be present in thymic tissue both in mice and in humans. The source of thymic exosomes is however still an enigma and hence it is not known whether thymic epithelial cells (TECs) are able to produce exosomes. In this work, we have cultured human TECs and isolated exosomes. These exosomes carry tissue-restricted antigens (TRAs), for example, myelin basic protein and desmoglein 3. The presence of TRAs indicates a possible role for thymic epithelium-derived exosomes in the selection process of thymocytes. The key contribution of these exosomes could be to disseminate self-antigens from the thymic epithelia, thus making them more accessible to the pool of maturing thymocytes. This would increase the coverage of TRAs within the thymus, and facilitate the process of positive and negative selection.

SUBMITTER: Skogberg G

PROVIDER: S-EPMC4575951 | biostudies-literature | 2015 Sep

REPOSITORIES: biostudies-literature

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Human thymic epithelial primary cells produce exosomes carrying tissue-restricted antigens.

Skogberg Gabriel G Lundberg Vanja V Berglund Martin M Gudmundsdottir Judith J Telemo Esbjörn E Lindgren Susanne S Ekwall Olov O

Immunology and cell biology 20150317 8

Exosomes are nano-sized vesicles released by cells into the extracellular space and have been shown to be present in thymic tissue both in mice and in humans. The source of thymic exosomes is however still an enigma and hence it is not known whether thymic epithelial cells (TECs) are able to produce exosomes. In this work, we have cultured human TECs and isolated exosomes. These exosomes carry tissue-restricted antigens (TRAs), for example, myelin basic protein and desmoglein 3. The presence of ...[more]

PMID: 25776846

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Project description:This SuperSeries is composed of the SubSeries listed below.

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