(A) Schematic model of the injection fragment for generating E2A-HLF transgenic mice. The Ig enhancer/promoter, the E2A-HLF cDNA, and the SV40 early splicing and poly(A) signals are shown as white, black, and shaded boxes, respectively. The positions of primers used for RT-PCR (P1-P4) are also indicated. The bar shows 1 kb. (B) Western blot analysis for the expression of theE2A-HLF transgene product in the thymus and spleen of a control mouse (C) and a transgenic mouse from two independent lines (1-17 and 2-17). The positions of E2A-HLF protein and Ig are indicated by arrows, and the positions of the molecular marker are shown on the left. (C) Immunofluorescent staining of the transgenic spleen with anti-B220 and anti-HLF antibodies. The B220-expressing and HLF-expressing cells are visualized by green and red signals, respectively.