Hairy Cell Leukemia, an Ultrastructural Study with Double Immunogold Labeling

Two cases of hairy cell leukemia were studied using a novel method of sequential double immunogold labeling for both scanning and transmission electron microscopy. Characteristic ribosome lamellae complexes were observed in one case only. The antigens expressed on the surface of hairy cells were those recognized by anti-CD 11c and anti-CD20 murine monoclonal antibodies. All hairy cells, in both cases, co-labeled for the corresponding antigens, as demonstrated by recognizing colloidal gold markers of distinct sizes (5 and 20 nm, or 15 and 40 nm) under SEM and TEM. The specificity of the double labeling method seems to be most satisfactory. Immuno-electron microscopy enables us to characterize the integrated ultrastructural and antigenic phenotype of hairy cells at the single cell level. This represents an unique analytical approach which may contribute significantly in further studies aimed at a better understanding of the pathogenesis of hairy cell leukemia.