Immunohistochemistry of ICAM-1. Liver sections were obtained after BMT at either day 7 or day 35 and tested for the protein for ICAM-1 as described in “Materials and methods.” (A) Day 7 after syngeneic BMT; (B) day 7 after allogeneic BMT; (C) day 35 after syngeneic BMT; and (D) day 35 after allogeneic BMT. ICAM-1 protein was clearly detected in the endothelium of portal vein and hepatic sinusoids after allogeneic BMT (B,D). No unspecific binding of the isotype control was detected (not shown). Methylgreen counterstain; original magnifications, × 400.