Characterization and cellular localization by monoclonal antibodies of the 60 kDa mannose specific lectin of human promyelocytic cells,HL60

Myelomonocytic lineage cells express anM_r 60 000 mannose specific lectin, MR60 (Pimpaneauet al. (1991),Carbohydr Res213: 95–108). Under non-reducing conditions, this protein migrates as a 120 000 protein. MR60 does not contain anyN-glycan moiety cleavable by the action ofN-glycanase. MR60 induces a sugar selective aggregation of beads coated with glycosylated albumin: beads bearing -d-mannosyl residues are aggregated while beads bearing -d-glucosyl residues are not. A monoclonal antibody Lec101B, specific for MR60, recognizes a singleM_r 60 000 protein by Western blotting. This monoclonal antibody does not label the cell surface of cells expressing MR60, but decorates intracellular vesicles upon permeabilization of these cells.