Salivary gland epithelial cell exosomes - A source of autoantigenic ribonucleoproteins

Kapsogeorgou, EK; Abu-Helu, RF; Moutsopoulos, HM; Manoussakis, MN

dc.contributor.author	Kapsogeorgou, EK	en
dc.contributor.author	Abu-Helu, RF	en
dc.contributor.author	Moutsopoulos, HM	en
dc.contributor.author	Manoussakis, MN	en
dc.date.accessioned	2014-03-01T01:54:47Z
dc.date.available	2014-03-01T01:54:47Z
dc.date.issued	2005	en
dc.identifier.issn	0004-3591	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/27460
dc.subject.classification	Rheumatology	en
dc.subject.other	SJOGRENS-SYNDROME	en
dc.subject.other	VESICLES	en
dc.subject.other	ACTIVATION	en
dc.subject.other	PROTEIN	en
dc.title	Salivary gland epithelial cell exosomes - A source of autoantigenic ribonucleoproteins	en
heal.type	journalArticle	en
heal.language	English	en
heal.publicationDate	2005	en
heal.abstract	Objective. Exosomes are membrane vesicles of endosomal origin that are distinct from apoptotic bodies and are thought to represent an acellular mechanism for antigen transfer to classic antigen-presenting cells, as well as for direct antigen presentation with the capacity to induce immune response or tolerance. Nevertheless, it is not known whether exosomes are involved in the induction or regulation of immune responses against intracellular autoantigens that characterize autoimmune diseases. Exosomes have been shown to be secreted by several types of cells, whereas studies of non-neoplastic epithelial cells are lacking. This study was undertaken to investigate the capacity of nonneoplastic salivary gland epithelial cells (SGECs) to release exosomes, and to determine whether epithelial exosomes contain RNPs, which are major autoantigens in systemic rheumatic diseases. Methods. Exosomes were isolated by ultracentrifugation from culture supernatants of 26 non-neoplastic SGEC lines established from patients with various rheumatic disorders. They were analyzed by electron microscopy, immunoblotting, or immunoprecipitation. Results. All SGEC lines were found to release comparable and significant amounts of exosomes. Similar to other cell systems, exosome secretion was constitutive and was unrelated to activation or apoptotic processes. SGEC-derived exosomes were found to contain the autoantigenic Ro/SSA, La/SSB, and Sm RNPs, as well as epithelial-specific cytokeratins. Conclusion. SGECs constitutively secrete exosomes that contain the major autoantigens Ro/SSA, La/SSB, and Sm. This mechanism may represent a pathway whereby intracellular autoantigens are presented to the immune system with an immunogenic or tolerogenic outcome.	en
heal.publisher	WILEY-LISS	en
heal.journalName	ARTHRITIS AND RHEUMATISM	en
dc.identifier.isi	ISI:000229004600021	en
dc.identifier.volume	52	en
dc.identifier.issue	5	en
dc.identifier.spage	1517	en
dc.identifier.epage	1521	en