Alexa Fluor^® 647 Rat Anti-Mouse IgD Antibody (S-R622)

IgD is a monomeric antibody isotype that, in humans, is primarily co-expressed with IgM on the surface of naïve B cells where it functions as an antigen receptor whose cytoplasmic tail participates in B-cell receptor signaling to modulate activation, survival, and differentiation; although it constitutes only about 0.25 % of serum immunoglobulin, secreted IgD appears to bind basophils and mast cells via galectin-9 to promote antimicrobial and inflammatory responses at mucosal surfaces, while its heavy chain constant region contains three immunoglobulin-like domains and undergoes extensive alternative splicing and class-switch recombination that together provide evolutionary flexibility and fine-tuned regulation of immune responses.