Although the specificity of Maackia amurensis lectin II (MAL II) is not well defined, it appears to bind only carbohydrate structures that contain sialic acid. Unlike Sambucus nigra lectin (SNA), which prefers structures with (α-2,6) linked sialic acid, MAL II binds sialic acid in an (α-2,3) linkage. Tissue staining patterns are also different among MAL I, SNA, and MAL II.