Premium
A Lectinlike Receptor on Murine Macrophage Cell Line Cells, Mm 1 : Involvement of Sialic Acid‐Binding Sites in Opsonin‐Independent Phagocytosis for Xenogeneic Red Cells
Author(s) -
Kyoizumi Seishi,
Masuda Tohru
Publication year - 1985
Publication title -
journal of leukocyte biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.819
H-Index - 191
eISSN - 1938-3673
pISSN - 0741-5400
DOI - 10.1002/jlb.37.3.289
Subject(s) - biology , cell culture , sialic acid , neuraminidase , biochemistry , opsonin , macrophage , microbiology and biotechnology , phagocytosis , enzyme , in vitro , genetics
The recognition mechanism of xenogenic red cells by mouse macrophages was studied by using established cell lines. Approximately 30% of cell line cells Mm 1 , which lack la antigen, as well as of thioglycollate‐induced peritoneal macrophages from SL/Am mice (TGC‐Mφ) could ingest unopsonized quail red cells (QRC). In contrast, an undifferentiated type of cell line, M 1 ″, and another type of macrophage cell line, Mk 1 C, possessing accessory cell activity in association with the expression of la antigen, had no phagocytic activity for QRC. Approximately 80% of Mm 1 , cells, as well as TGC‐Mφ formed rosettes with QRC, whereas M 1 and Mk 1 C cells did not; indicating that specific binding sites for QRC are expressed on a large portion of Mm 1 and TGC‐Mφ but not on M 1 ‐ and Mk 1 ,‐C cells. No requirement of divalent cation (Mg ++ , Ca ++ ) and metabolic energy was observed for rosette formation between Mm 1 cells and QRC. Protease treatment of Mm 1 cells eliminated the rosetting activity, whereas periodate oxidation or glycosidase treatment slightly enhanced this activity, suggesting the involvement of surface protein in binding sites of Mm 1 , cells. In contrast to these findings on Mm 1 cells, binding components of QRC were sensitive to periodate oxidation or neuraminidase treatment but resistant to protease, suggesting that the terminal sialic acid residues of carbohydrate of QRC are recognized by Mm 1 , cells. Furthermore, N‐acetylneuraminic acid (NeuNAc) inhibited the rosette formation and promoted the dissociation of rosettes already formed. N‐Acetylneuramin lactose (NeuNAc‐Lact) was more efficient in rosette inhibition than NeuNAc. These sugars also blocked the phagocytosis of QRC by Mm 1 cells but had no effect on either Fc‐mediated phagocytosis or latex ingestion. These results suggest that phagocytosis of QRC by murine macrophages is mediated by protease‐sensitive binding sites recognizing terminal sialic acid residues of QRC in conjunction with additional carbohydrates.