Fig. 4

Splenic B^VETrp53^KO or B^VEpTEN^KO leukemic cells resemble hairy cells in human HCL. A-D Differential expression of human HCL markers (CD11c and CD103) by splenic B cells of HSC^VE, B^VEP53^−/−, and B^VEPTEN^−/− mice at the terminal stage of disease. Splenocytes were stained with anti-B220 and CD11c (A-B) or CD103 (C-D) antibodies and analyzed by flow cytometry. A and C show 2D plots of B220 versus CD11C or CD103. B and D show histograms and geometric means of CD11c or CD103 in B220⁺ populations. E The HSC^VE, B^VEP53^−/−, and B^VEPTEN^−/− leukemic cells exhibited different cellular morphologies from normal B-lymphocytes. Splenic B cells isolated from HSC^VE, B^VEP53^−/−, and B^VEPTEN^−/− mice at the terminal stage of disease were stained with Giemsa and imaged by a microscope. Hairy projections were observed on most B^VEPTEN^−/− leukemic cells, partially on B^VEP53^−/− leukemic cells, and rarely on HSC^VE leukemic cells (Scale = 10 μm). The ratios of hairy cells in purified leukemic cells were calculated manually and represent average values from at least five samples. F HSC^VE, B^VEP53^−/−, and B^VEPTEN^−/− leukemic cells highly expressed the human HCL marker, Annexin A1. Whole lysates of splenic B cells isolated from different mice strains with or without disease was measured for the expression of Annexin A1 by SDS-PAGE and immunoblot. In all experiments, splenocytes or B cells isolated from 28-week-old wild type or B^VE or B^VEP27^−/− mice served as controls. All images are representative of at least five mice per group and three independent experiments