title: Marginal Zone Macrophage Receptor MARCO Is Trapped in Conduits Formed by Follicular Dendritic Cells in the Spleen.
abstract: The marginal zone (MZ) region of the spleen plays an important role in leukocyte traffic and the removal of blood-borne pathogens by resident macrophages. Macrophage receptor with a collagenous structure (MARCO), expressed by MZ macrophages, recognizes several microbial ligands and is also involved in the retention of MZ B cells. Here, we report that MARCO is also associated with follicular dendritic cells (FDCs) in the spleen. In its FDC-associated form MARCO is arranged in 0.3-0.5-μm diameter granular-fibrillar structures with an appearance similar to the white pulp conduit system formed by fibroblastic reticular cells (FRCs), but with different compartment preference. The follicular display of MARCO resists irradiation and requires the presence of both MZ macrophages and differentiated FDCs. The follicular delivery of MARCO is independent from the shuffling of marginal zone B cells, and it persists after clodronate liposome-mediated depletion of MZ macrophages. Our findings thus indicate that MARCO is distributed to both MZ and follicles within the spleen into conduit-like structures, where FDC-bound MARCO may mediate communication between the stromal microenvironments of MZ and follicles.
authors.affiliation: Department of Immunology & Biotechnology (ZK,VF,MM,PB) University of Pécs, Pécs, HungaryDepartment of Medical Biology, (GB) University of Pécs, Pécs, HungaryDepartment of Oncotherapy (JK) University of Pécs, Pécs, HungaryLymphoid Organogenesis Research Group, Szentágothai János Research Center (ZK,PB) University of Pécs, Pécs, Hungary.
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Kellermayer
authors.affiliation: Department of Immunology & Biotechnology (ZK,VF,MM,PB) University of Pécs, Pécs, HungaryDepartment of Medical Biology, (GB) University of Pécs, Pécs, HungaryDepartment of Oncotherapy (JK) University of Pécs, Pécs, HungaryLymphoid Organogenesis Research Group, Szentágothai János Research Center (ZK,PB) University of Pécs, Pécs, Hungary.
authors.forename: Viktória
authors.initials: V
authors.lastname: Fisi
authors.affiliation: Department of Immunology & Biotechnology (ZK,VF,MM,PB) University of Pécs, Pécs, HungaryDepartment of Medical Biology, (GB) University of Pécs, Pécs, HungaryDepartment of Oncotherapy (JK) University of Pécs, Pécs, HungaryLymphoid Organogenesis Research Group, Szentágothai János Research Center (ZK,PB) University of Pécs, Pécs, Hungary.
authors.forename: Martina
authors.initials: M
authors.lastname: Mihalj
authors.affiliation: Department of Immunology & Biotechnology (ZK,VF,MM,PB) University of Pécs, Pécs, HungaryDepartment of Medical Biology, (GB) University of Pécs, Pécs, HungaryDepartment of Oncotherapy (JK) University of Pécs, Pécs, HungaryLymphoid Organogenesis Research Group, Szentágothai János Research Center (ZK,PB) University of Pécs, Pécs, Hungary.
authors.forename: Gergely
authors.initials: G
authors.lastname: Berta
authors.affiliation: Department of Immunology & Biotechnology (ZK,VF,MM,PB) University of Pécs, Pécs, HungaryDepartment of Medical Biology, (GB) University of Pécs, Pécs, HungaryDepartment of Oncotherapy (JK) University of Pécs, Pécs, HungaryLymphoid Organogenesis Research Group, Szentágothai János Research Center (ZK,PB) University of Pécs, Pécs, Hungary.
authors.forename: József
authors.initials: J
authors.lastname: Kóbor
authors.affiliation: Department of Immunology & Biotechnology (ZK,VF,MM,PB) University of Pécs, Pécs, HungaryDepartment of Medical Biology, (GB) University of Pécs, Pécs, HungaryDepartment of Oncotherapy (JK) University of Pécs, Pécs, HungaryLymphoid Organogenesis Research Group, Szentágothai János Research Center (ZK,PB) University of Pécs, Pécs, Hungary balogh.peter@pte.hu.
authors.forename: Péter
authors.initials: P
authors.lastname: Balogh
keywords: MARCO; conduit; follicular dendritic cells; marginal zone macrophages