Cellular localization of the galactose-binding lectin from human serum

An SL2 lectin was isolated from human serum and characterized previously: c ellular localization of the lectin was studied using polyclonal rabbit anti bodies. According to cytofluorimetry, anti-SL2 antibodies bound only to lym phocytes and monocytes bur not to other blood cells. Antibodies bound to Ju rkat T cell lymphoma but did not interact with IM-9 cells of B cell origin. Moreover, the Jurkat cells bound oligosaccharides having the highest affin ity to SL2 (GalNAc alpha and Fuc alpha1-2Gal), and this interaction was inh ibited by anti-SL2 antibodies. Lysis of the Jurkat cells with subsequent el ectrophoresis and Western blotting indicates that anti-SL2 antibodies recog nized a 14-kD protein.