Affinity-purified Amaranthus caudatus (ACL/ACA) is a dimer glycoprotein made up of two subunits. ACL has preferential specificity to oliogsacharrides containing the galactosyl disacharride GalÎ²3GalNAc. ACL tolerates sialic acid substitution at the 3 position of galactose in the â€œTâ€ antigen. It does not have specificity for blood groups but does have a higher affinity for type O erythrocytes over B and A. Texas Red is a red-fluorescent dye and when bound to Amaranthus caudatus Lectin (ACL/ACA) can show the binding pattern of this lectin in cellular imaging applications. There is very little overlap between the emission spectra of Texas Red and FITC making this combination ideal for dual-labeling experiments. Rhodamine dyes, such as Texas Red, are more photostable and less sensitive to pH change when compared to other dyes such as fluorescein.