title: Proteomic characterization of thymocyte-derived microvesicles and apoptotic bodies in BALB/c mice.
abstract: Several studies have characterized exosomes derived from different cell sources. In this work we set the goal of proteomic characterization of two less studied populations of membrane vesicles, microvesicles (100-800 nm) and apoptotic bodies (> 800 nm) released by thymus cells of BALB/c mice. The vesicles were isolated by the combination of differential centrifugation and gravity driven multistep filtration of the supernatant of thymus cell cultures. The size distribution of vesicle preparations was determined by transmission electron microscopy. Proteins were released from the vesicles, digested in solution, and analyzed using nano-HPLC/MS(MS). Ingenuity pathway analysis was used to identify functions related to membrane vesicle proteins. In apoptotic bodies and microvesicles we have identified 142 and 195 proteins, respectively. A striking overlap was detected between the proteomic compositions of the two subcellular structures as 108 proteins were detected in both preparations. Identified proteins included autoantigens implicated in human autoimmune diseases, key regulators of T-cell activation, molecules involved in known immune functions or in leukocyte rolling and transendothelial transmigration. The presence and abundance of proteins with high immunological relevance within thymocyte-derived apoptotic bodies and microvesicles raise the possibility that these subcellular structures may substantially modulate T-cell maturation processes within the thymus.
authors.affiliation: Chemical Research Center of the Hungarian Academy of Sciences, Budapest, Pusztaszeri út 59-67, 1025, Hungary.
authors.forename: Lilla
authors.initials: L
authors.lastname: Turiák
authors.forename: Petra
authors.initials: P
authors.lastname: Misják
authors.forename: Tamás G
authors.initials: TG
authors.lastname: Szabó
authors.forename: Borbála
authors.initials: B
authors.lastname: Aradi
authors.forename: Krisztina
authors.initials: K
authors.lastname: Pálóczi
authors.forename: Oliver
authors.initials: O
authors.lastname: Ozohanics
authors.forename: László
authors.initials: L
authors.lastname: Drahos
authors.forename: Agnes
authors.initials: A
authors.lastname: Kittel
authors.forename: András
authors.initials: A
authors.lastname: Falus
authors.forename: Edit I
authors.initials: EI
authors.lastname: Buzás
authors.forename: Károly
authors.initials: K
authors.lastname: Vékey
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000276:immunology; D055354:Exosomes / Q000378:metabolism*; D008565:Membrane Proteins / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D040901:Proteomics; D060168:Thymocytes / Q000648:ultrastructure*
chemical_list: D008565:Membrane Proteins