title: Splenic red pulp macrophages are intrinsically superparamagnetic and contaminate magnetic cell isolates.
abstract: A main function of splenic red pulp macrophages is the degradation of damaged or aged erythrocytes. Here we show that these macrophages accumulate ferrimagnetic iron oxides that render them intrinsically superparamagnetic. Consequently, these cells routinely contaminate splenic cell isolates obtained with the use of MCS, a technique that has been widely used in immunological research for decades. These contaminations can profoundly alter experimental results. In mice deficient for the transcription factor SpiC, which lack red pulp macrophages, liver Kupffer cells take over the task of erythrocyte degradation and become superparamagnetic. We describe a simple additional magnetic separation step that avoids this problem and substantially improves purity of magnetic cell isolates from the spleen.
authors.affiliation: Institute of Experimental Immunology, Rheinische Friedrich-Wilhelms-University, Sigmund-Freud-Straße 25, 53105 Bonn, Germany.
authors.forename: Lars
authors.initials: L
authors.lastname: Franken
authors.affiliation: Institute of Experimental Immunology, Rheinische Friedrich-Wilhelms-University, Sigmund-Freud-Straße 25, 53105 Bonn, Germany.
authors.forename: Marika
authors.initials: M
authors.lastname: Klein
authors.affiliation: Faculty for Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University Duisburg-Essen, Lotharstraße 1, 47057 Duisburg, Germany.
authors.forename: Marina
authors.initials: M
authors.lastname: Spasova
authors.affiliation: Faculty for Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University Duisburg-Essen, Lotharstraße 1, 47057 Duisburg, Germany.
authors.forename: Anna
authors.initials: A
authors.lastname: Elsukova
authors.affiliation: Faculty for Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University Duisburg-Essen, Lotharstraße 1, 47057 Duisburg, Germany.
authors.forename: Ulf
authors.initials: U
authors.lastname: Wiedwald
authors.affiliation: 1] Institute of Experimental Immunology, Rheinische Friedrich-Wilhelms-University, Sigmund-Freud-Straße 25, 53105 Bonn, Germany [2] Institute of Molecular Immunology, Technical University Munich, Schneckenburgerstr. 8, 81675 Munich, Germany.
authors.forename: Meike
authors.initials: M
authors.lastname: Welz
authors.affiliation: Institute of Molecular Immunology, Technical University Munich, Schneckenburgerstr. 8, 81675 Munich, Germany.
authors.forename: Percy
authors.initials: P
authors.lastname: Knolle
authors.affiliation: Faculty for Physics and Center for Nanointegration Duisburg-Essen (CENIDE), University Duisburg-Essen, Lotharstraße 1, 47057 Duisburg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Farle
authors.affiliation: Clinic for Orthopaedics and Trauma Surgery Bonn, University Clinic Bonn, Sigmund-Freud-Straße 25, 53105 Bonn, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Limmer
authors.affiliation: Institute of Experimental Immunology, Rheinische Friedrich-Wilhelms-University, Sigmund-Freud-Straße 25, 53105 Bonn, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Kurts
mesh_terms: D000818:Animals; D001772:Blood Cell Count; D019070:Cell Lineage; D002469:Cell Separation / Q000379:methods*; D004912:Erythrocytes / Q000378:metabolism*; D052203:Ferrosoferric Oxide / Q000009:adverse effects / Q000737:chemistry; D005434:Flow Cytometry; D006801:Humans; D008099:Liver / Q000166:cytology; D008264:Macrophages / Q000166:cytology* / Q000378:metabolism; D051379:Mice; D010587:Phagocytosis; D013154:Spleen / Q000166:cytology* / Q000378:metabolism
chemical_list: C427127:superparamagnetic blood pool agent; D052203:Ferrosoferric Oxide