title: Activated macrophages release microvesicles containing polarized M1 or M2 mRNAs.
abstract: MVs are known vehicles of horizontal communication among cells, currently under scrutiny as powerful biomarkers in several pathological processes. The potential advantage of MVs relies on the assumption that their content reflects processes ongoing in pathologically relevant cell types. We have described that MVs of myeloid origin in the CSF are a marker of microglia/macrophage activation. Myeloid cells have different activation types, resulting in diverse functional phenotypes. Knowledge on the activation type of myeloid cells during disease would be of paramount importance for the understanding of ongoing pathogenic processes. We show here that macrophages activated in vitro in different ways all release increased amounts of MVs compared with NS cells. Moreover, we show that macrophage-derived MVs contain a repertoire of mRNAs that is not the result of casual sampling from the parental cells, as it is characterized by distinct mRNA enrichments and species. Nevertheless, mRNA content of MVs clearly allows identification in vivo of the activated phenotype of the cell of origin, indicating carryover of functional macrophage traits. We propose that detection of mRNAs in myeloid MVs permits identification of myeloid cell activation type during disease, allowing for further stratification of pathological processes.
authors.affiliation: Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Milano, Italy.
authors.forename: Livia
authors.initials: L
authors.lastname: Garzetti
authors.affiliation: Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Milano, Italy.
authors.forename: Ramesh
authors.initials: R
authors.lastname: Menon
authors.affiliation: Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Milano, Italy.
authors.forename: Annamaria
authors.initials: A
authors.lastname: Finardi
authors.affiliation: Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Milano, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Bergami
authors.affiliation: Humanitas Clinical and Research Center, Rozzano, Italy; and.
authors.forename: Antonio
authors.initials: A
authors.lastname: Sica
authors.affiliation: Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Milano, Italy.
authors.forename: Gianvito
authors.initials: G
authors.lastname: Martino
authors.affiliation: Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Milano, Italy.
authors.forename: Giancarlo
authors.initials: G
authors.lastname: Comi
authors.affiliation: Humanitas Clinical and Research Center, Rozzano, Italy; and.|Consiglio Nazionale delle Ricerche, Institute of Neuroscience, Milano, Italy.
authors.forename: Claudia
authors.initials: C
authors.lastname: Verderio
authors.affiliation: Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Milano, Italy.
authors.forename: Cinthia
authors.initials: C
authors.lastname: Farina
authors.affiliation: Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Milano, Italy; furlan.roberto@hsr.it.
authors.forename: Roberto
authors.initials: R
authors.lastname: Furlan
mesh_terms: D000818:Animals; D055252:Cell-Derived Microparticles / Q000276:immunology*; D005260:Female; D008262:Macrophage Activation; D017737:Macrophages, Peritoneal / Q000276:immunology*; D051379:Mice; D012333:RNA, Messenger / Q000276:immunology*
chemical_list: D012333:RNA, Messenger
keywords: cytokines; inflammation