Affinity purified Euonymus europaeus lectin or agglutinin (EEL/EEA) is composed with most of the subunits that appear to consist of two chains linked by disulfide bonds. EEL consists of six closely related lectins (isoforms). EEL is identified for its erythrocyte agglutinating properties and specificity for blood groups B and H. It has a stronger binding of the H trisaccharide over the B trisaccharide, but has a general pattern of interacting with both B and H blood groups and α-mannose-terminated saccharides. EEL has a preferential recognition of terminal α-fucose residues in H and B blood group-related carbohydrates. This lectin binds to endothelial cells from human and non-human sources and recognizes carbohydrate structures on the surface of stimulated murine peritoneal lymphoid cells. See other EEL/EEA conjugates.Cy5, when bound to Euonymus europaeus Lectin (EEL/EEA), can show the binding pattern of this lectin in cellular imaging and flow cytometry. The excitation wavelength required for Cy5 to fluoresce is high enough to avoid overlap with most other fluorochromes, making it useful for dual-labeling experiments. Because of this high excitation, there is typically less background from autofluorescence of biological specimens.