Schematic representation of the MSCVneo P230 BCR/ABL vector and macroscopic and histopathologic findings of founder mice no. 13 and no. 22. (A) The injection fragment for generating transgenic mice was made by cutting at PvuI and SspI sites of the bacterial plasmid, pUC19. Two vertical arrows indicate the cutting sites. P indicates PvuI; S, SspI. The nucleotide sequences of the primers for PCR were as follows: BCR/abl-F: 5′-TGACCAACTCGTGTGTGAAACTCCAG-3′; and BCR/abl-R: 5′-CAGCAGATAC TCAGCGGCATTG-3′. (B) Macroscopic appearance of founder mouse no. 13 in the extramedullary blastic phase of MPD. (i) A markedly enlarged liver and a large volume of hemorrhage in the peritoneal cavity are seen. (ii) After removal of the liver, the enlarged spleen is visible. (C) Histopathologic findings of founder mice no. 13 and no. 22. Photomicrographs of hematoxylin and eosin-stained spleen (i-iii), bone marrow (iv-vi), lung (vii-ix), and liver (x-xii); Wright-Giemsa-stained peripheral blood (xiii-xv); from no. 22 (ii,v,viii,xi,xiv), no. 13 (iii,vi,ix,xii,xv-xvii), and a nontransgenic littermate mouse killed at 12 months of age (i,iv,vii,x,xiii). Panels xvi and xvii show the immunohistochemical findings of the liver stained with Gr-1 (xvii) and control IgG (xvi). Blasts were positive for Gr-1. Original magnifications: × 200 (i-iii); × 1000 (panels xiii-xv); × 400 (iv-xii, xvi); and × 800 (xvii).