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Published on: August 1, 2012
MUM-4, a monoclonal antibody reacting with resident peritoneal mouse macrophages
1Department of Medical Microbiology, Odense University, Denmark.
Abstract:
A new rat monoclonal antibody, MUM-4, which recognizes a murine antigen/epitope that is absent on monocytes, strongly expressed on resident peritoneal macrophages and almost completely absent from peritoneal macrophages 4 days after an intraperitoneal injection of thioglycollate or heat-killed Propionibacterium acnes organisms, is described. Immunocytochemistry and flow cytometry have been used to characterize the specificity of the antibody. MUM-4 did not react with blood granulocytes, peritoneal exudate granulocytes, lymphocytes from blood or peritoneum, isolated spleen dendritic cells, or veiled cells from the thoracic duct of mesenteric lymphadenectomized mice. The MUM-4 antibody reacted with resident peritoneal macrophages from all the mouse strains studied. MUM-4 appears to represent a new specificity. The MUM-4 antibody is of the rat IgG2c isotype and exhibits complement-mediated cytotoxicity with rabbit complement. The staining achieved with MUM-4 by FACS or immunocytochemical methods is intense on most resident peritoneal macrophages and the antibody should be a valuable addition to the panel of monoclonal antibodies available for studies on mouse macrophages.
Insights
Researchers developed a new rat monoclonal antibody, MUM-4, identifying a unique macrophage marker. This antibody aids in studying mouse macrophages, distinguishing them from monocytes and other immune cells.
Area of Science:
- Immunology
- Cell Biology
Background:
- Monoclonal antibodies are crucial tools for characterizing immune cell populations.
- Resident peritoneal macrophages play key roles in innate immunity and tissue homeostasis.
- Specific markers are needed to differentiate macrophage subsets and their functions.
Purpose of the Study:
- To describe a novel rat monoclonal antibody, MUM-4, targeting a specific antigen on mouse macrophages.
- To characterize the specificity and utility of MUM-4 for macrophage research.
Main Methods:
- Production and characterization of rat monoclonal antibody MUM-4.
- Immunocytochemistry and flow cytometry (FACS) for antibody specificity analysis.
- Testing reactivity against various mouse immune cells, including monocytes, granulocytes, lymphocytes, dendritic cells, and veiled cells.
Main Results:
- MUM-4 recognizes a murine antigen/epitope absent on monocytes but strongly expressed on resident peritoneal macrophages.
- The antigen is downregulated on peritoneal macrophages following thioglycollate or P. acnes challenge.
- MUM-4 shows no reactivity with granulocytes, lymphocytes, dendritic cells, or veiled cells.
- The antibody reacts consistently with resident peritoneal macrophages across different mouse strains.
- MUM-4 is of rat IgG2c isotype and mediates complement-dependent cytotoxicity.
Conclusions:
- MUM-4 represents a new specificity for identifying mouse macrophages.
- The antibody provides intense staining on resident peritoneal macrophages via FACS and immunocytochemistry.
- MUM-4 is a valuable tool for immunological studies involving mouse macrophages.
