The GA-R2 (also known as HIR2) monoclonal antibody specifically binds to CD235a and CD235b. CD235a is also known as Glycophorin A (GYPA, GPA, GLPA), Sialoglycoprotein alpha, MN sialoglycoprotein, or PAS-2. CD235b is otherwise known as Glycophorin B (GYPB, GPB, GLPB), Sialoglycoprotein delta, SS-active sialoglycoprotein, or PAS-3. CD235a and CD235b are type I transmembrane sialoglycoproteins that are expressed on human erythrocytes, erythroid precursor cells and certain leukemic cell types. CD235a carries blood group M and N antigens, whereas CD235b contains S, s, and U antigens. This antibody is useful for the identification and characterization of erythrocytes, certain myeloid leukemic cell types, and studies of erythroid cell development and infectious diseases with erythrocyte involvement. Glycophorins may play a role in preventing cell agglutination.
The antibody was conjugated to BD Horizon™ BV711 which is part of the BD Horizon Brilliant™ Violet family of dyes. This dye is a tandem fluorochrome of BD Horizon BV421 with an Ex Max of 405-nm and an acceptor dye with an Em Max at 711-nm. BD Horizon BV711 can be excited by the violet laser and detected in a filter used to detect Cy™5.5 / Alexa Fluor® 700-like dyes (eg, 712/20-nm filter). Due to the excitation and emission characteristics of the acceptor dye, there may be moderate spillover into the Alexa Fluor® 700 and PerCP-Cy5.5 detectors. However, the spillover can be corrected through compensation as with any other dye combination.