The monoclonal antibody 15-2 recognizes the mannose receptor (MR), also known as CD206, a member of the vertebrate C-type lectin family. The mannose receptor, is a pattern recognition receptor that is involved in both innate and adaptive immunity. The 175 kDa single-pass type I transmembrane receptor consists of 5 domains: an amino-terminal cysteine-rich region, a fibronectin type II repeat, a series of eight tandem lectin-like carbohydrate recognition domains (responsible for the recognition of mannose and fucose), a transmembrane domain, and an intracellular carboxy-terminal tail.
The structure is shared by the family of multi lectin mannose receptors: the phospholipase A2-receptor, DEC 205 and the novel C-type lectin receptor (mannose receptor X). The MR binds high-mannose structures on- a wide range of gram positive and gram negative bacteria, yeasts, parasites and mycobacteria. The MR has also been shown to bind and internalize tissue-type plasminogen activator.
MR’s are present on monocytes and dendritic cells (DC) and are presumed to play a role in innate and adaptive immunity, the latter via processing by DC. The expression of MR as observed in immunohistology is present on tissue macrophages, dendritic cells, a subpopulation of endothelial cells, Kupffer cells and sperm cells. The expression of MR on monocytes increases during culture and can be enhanced by cytokines as IFN-gamma. Labeling of MR expressing monocytes/macrophages increases with prolonged incubation time probably due to internalization of the MR-antibody-complex. The monoclonal antibody 15-2 prevents binding of glycoproteins including t-PA to MR.
Detection of the MR with anti-MR monoclonal antibody 15-2 can substitute staining for mannose containing probes as labeled mannosylated BSA, a technique which is more cumbersome and less specific.
Flow cytometry, Frozen sections, Functional studies, Western blot
F: Tissue sections were fixed in acetone/chloroform. Sections were preincubated with normal rabbit serum (Ref.3).
FC: Antibody 15-2 stains the extracellular domain of MR.
W: A non-reduced sample treatment and 6% SDS-Page was used. The band size is 175 kDa (Ref.1).
FS: Antibody 15-2 functions as an inhibitor of binding. The antibody was functionally tested by preincubation of immobilized receptor with antibody. This prevented binding of t-PA to immobilized receptor. (Ref.1).
Dilutions to be used depend on detection system applied. It is recommended that users test the reagent and determine their own optimal dilutions. The typical starting working dilution is 1:50.
Macrophages (in coronary atherosclerotic plaque), placenta tissue, Hofbauer cells (fetal macrophages), liver tissue