title: Phenotyping of Leukocytes and Leukocyte-Derived Extracellular Vesicles.
abstract: Extracellular vesicles (EVs) have a demonstrated involvement in modulating the immune system. It has been proposed that EVs could be used as biomarkers for detection of inflammatory and immunological disorders. Consequently, it is of great interest to investigate EVs in more detail with focus on immunological markers. In this study, five major leukocyte subpopulations and the corresponding leukocyte-derived EVs were phenotyped with focus on selected immunological lineage-specific markers and selected vesicle-related markers. The leukocyte-derived EVs displayed phenotypic differences in the 34 markers investigated. The majority of the lineage-specific markers used for identification of the parent cell types could not be detected on EVs released from monocultures of the associated cell types. In contrast, the vesicular presentation of CD9, CD63, and CD81 correlated to the cell surface expression of these markers, however, with few exceptions. Furthermore, the cellular expression of CD9, CD63, and CD81 varied between leukocytes present in whole blood and cultured leukocytes. In summary, these data demonstrate that the cellular and vesicular presentation of selected lineage-specific and vesicle-related markers may differ, supporting the accumulating observations that sorting of molecular cargo into EVs is tightly controlled.
authors.affiliation: Department of Clinical Immunology, Aalborg University Hospital, 9000 Aalborg, Denmark.
authors.forename: Lotte Hatting
authors.initials: LH
authors.lastname: Pugholm
authors.affiliation: Department of Clinical Immunology, Aalborg University Hospital, 9000 Aalborg, Denmark.
authors.forename: Rikke
authors.initials: R
authors.lastname: Bæk
authors.affiliation: Department of Clinical Immunology, Aalborg University Hospital, 9000 Aalborg, Denmark.
authors.forename: Evo Kristina Lindersson
authors.initials: EK
authors.lastname: Søndergaard
authors.affiliation: Department of Clinical Immunology, Aalborg University Hospital, 9000 Aalborg, Denmark.
authors.forename: Anne Louise Schacht
authors.initials: AL
authors.lastname: Revenfeld
authors.affiliation: Department of Clinical Immunology, Aalborg University Hospital, 9000 Aalborg, Denmark.
authors.forename: Malene Møller
authors.initials: MM
authors.lastname: Jørgensen
authors.affiliation: Department of Clinical Immunology, Aalborg University Hospital, 9000 Aalborg, Denmark.
authors.forename: Kim
authors.initials: K
authors.lastname: Varming
mesh_terms: D015703:Antigens, CD; D015415:Biomarkers; D016022:Case-Control Studies; D019070:Cell Lineage; D002478:Cells, Cultured; D000067128:Extracellular Vesicles / Q000378:metabolism*; D006801:Humans; D016130:Immunophenotyping; D007962:Leukocytes / Q000378:metabolism*; D010641:Phenotype
chemical_list: D015703:Antigens, CD; D015415:Biomarkers