A library of mutated Maackia amurensis hemagglutinin distinguishes putative glycoforms of immunoglobulin A1 from IgA nephropathy patients.

Ten genetically modified Maackia amurensis hemagglutinin (MAH) clones at the carbohydrate-recognition loop were found to bind glycophorin A and a mucin mimetic with NeuAcalpha2-3Galbeta1-3GalNAcalpha (monosialyl-T antigen) in different relative intensity. Binding profiles of these lectins to human serum IgA1 from healthy individuals and from IgA nephropathy patients were subjected to the cluster analysis. Two large groups, one with only healthy individuals and another with all IgA nephropathy patients, were generated.

Use of a library of mutated Maackia amurensis hemagglutinin for profiling the cell lineage and differentiation.

Thirty-five variant lectins were prepared by mutations of two amino acids within the carbohydrate-recognition domain of Maackia amurensis hemagglutinin (MAH). Each lectin showed unique carbohydrate specificity according to their bindings to soluble polyacrylamide with various mono- and oligosaccharides and to glycophorin A. The relative intensity of the bindings of carcinoma, myeloid, fibroblastic, and melanoma cells to immobilized MAH variant lectins was examined.

The amino acids involved in the distinct carbohydrate specificities between macrophage galactose-type C-type lectins 1 and 2 (CD301a and b) of mice.

Binding specificities of mouse macrophage galactose-type C-type lectin 1 (MGL1/CD301a) and 2 (MGL2/CD301b) toward various oligosaccharides were compared by frontal affinity chromatography. MGL1 preferentially bound oligosaccharides containing Lewis(X) (Le(X)) trisaccharides among 111 oligosaccharides tested, whereas MGL2 preferentially bound globoside Gb4. The important amino acids for the preferential bindings were investigated by pair-wise site-directed mutagenesis at positions 61, 89, 97, 100, 110-113, 115, 124, and 125 in the soluble recombinant carbohydrate recognition domains (CRD) prepared in Escherichia coli and purified with galactose-Sepharose.