CD4+ T-cell and B220+ B-cell infiltration is seen in lungs and livers of transplanted animals. Liver and lung tissues were harvested at day 60 after transplantation from animals receiving BM only and BM plus splenocytes (BM + spleen) and analyzed by immunohistochemistry and methyl blue counterstaining. Representative images from 3 individual experiments are shown for CD4 (A) and B220 (D). Images were captured with a bright-field microscope at 200× magnification. For lung, infiltration was quantified by obtaining a ratio of CD4+ (B) or B220+ (E) cells to total cells in a 100-mm2 field of view under the microscope. Shown is an average of the count from 4 representative fields. For liver, CD4 (C) and B220 (F) cell infiltration was quantified by counting the number of antibody binding–positive cells and obtaining an average of counts from 4 representative fields. n = 6. *P < .05; **P < .01; ***P < .005.
