Retrovirus-mediated gene transfer of WASP in WKO HSCs can ameliorate or prevent colitis in RAG-2 recipient mice.

Shown are representative H and E–stained cross-sections of recipient mouse colons after stem cell transplantation. (A) WT HSCs transduced with CMMP-GFP: no colitis. (B) WKO HSCs transduced with CMMP-GFP: severe colitis; note increased diameter due to epithelial hyperplasia and leukocyte infiltration into the lamina propria. (C) WKO HSCs transduced with CMMP-WASP-IRES-GFP: no colitis. Untreated RAG-KO mice do not develop colitis. Original magnification × 40 for all panels.