Rat Macrophage C-Type Lectin Is an Activating Receptor Expressed by Phagocytic Cells

Abstract

Macrophage C-type lectin (MCL) is a membrane surface receptor encoded by the Antigen Presenting Lectin-like gene Complex (APLEC). We generated a mouse monoclonal antibody for the study of this receptor in the rat. We demonstrate that rat MCL is expressed on blood monocytes and neutrophils, as well as on several tissue macrophage populations, including alveolar and peritoneal cavity macrophages. We also demonstrate MCL expression on a subset of resident spleen macrophages. Immunohistochemistry analysis of the spleen showed staining specifically in the marginal zone and red pulp. Exposure to pro-inflammatory mediators or to yeast cell wall extract (zymosan) increased surface MCL expression on peritoneal macrophages. We characterized a rat myeloid cell line, RMW, which expresses high levels of MCL. We found that MCL co-immunoprecipitated with the activating adaptor protein FcεRIγ in these cells. Moreover, beads coated with anti-MCL antibody increased phagocytosis in the RMW cells. Together, these observations indicate that rat MCL is a receptor that activates phagocytosis in myeloid cells under inflammatory conditions.

Theα4 Nicotinic Receptor Promotes CD4+T-Cell Proliferation and a Helper T-Cell Immune Response

“…Spleen extraction and histologic preparation were performed as described elsewhere (Lobato-Pascual et al, 2013). Briefly, adult mice were anesthetized using 5% isoflurane and then perfused using 4% paraformaldehyde, pH 7.2.…”

Immune Interactions with Pathogenic and Commensal Fungi: A Two-Way Street

“…Another study found that MCL interacts with FcRγ in rat myeloid cells but not in transfected non-myeloid cells, suggesting that the interaction is indirect (Lobato-Pascual et al, 2013a). However, subsequent studies have shown that MCL-FcRγ interaction and signaling requires Mincle and formation of MCL-Mincle heterodimers (Lobato-Pascual et al, 2013b).…”

Listeria monocytogenes infection differentially affects expression of ligands for NK cells and NK cell responses, depending on the cell type infected

“…In search for an appropriate cell line to mimic this phenomenon, we screened a number of rat cells retrieved from different sources. One of these cell lines was the RmW, originally derived as a side‐product of a T cell leukemia cell line (Roser Leukaemia) . The RmW cell line has not previously been fully described and therefore, was characterized by using an array of rat mAb (Table ).…”

“…The myeloid cell line RmW originates from PVG ( RT1 c haplotype) rat spleen as a side product during the generation of an in vitro passageable variant of the in vivo‐restricted Roser leukemia (a rat T cell leukemic cell line) . The phenotype of this cell line was determined by flow cytometry using a panel of mAb specific for the rat (listed in Table ).…”