Subsets of CD10⁺/CD19⁺ lymphoblasts express ICAM1, LFA-1, and cause CNS disease in mice. (A) The CD10⁺/CD19⁺ cell population of patients with relapsed ALL significantly overexpress LFA-1/ICAM1/CD70 compared with the CD10⁺/CD19⁺ cell populations of normal volunteers (controls) and those with de novo disease. Horizontal lines denote mean values. (B) Histopathological sections obtained from a representative mouse transplanted with cells from patient 36 (purple circle in panel A). The left panel shows infiltration of cranial bone marrow by ICAM1- and LFA-1–positive leukemic cells. The right panel shows infiltration of CD45-positive cells along the optic nerve. Images were captured on a Mirax scanner (3Dhistech) using a Zeiss Fluor 20×/0.75 NA objective lens and a Marlin (Allied Vision Technologies) color camera. The system uses the 3DHistech scan software, and images were viewed and exported using 3DHistech panoramic viewer software.