Normal colon histology in C57−WAS− mouse after transplantation.

Hematoxylin and eosin–stained section from the colon of a C57/BL6J WAS-null mouse (age 10 weeks, H hepaticuspositive) that became acutely ill and was killed 10 days after lethal irradiation and bone marrow transplantation. A severe hemorrhagic cystitis was found at necropsy. Colon histology shows rare acute and chronic inflammatory cells, but is essentially normal. Magnification, × 50.