Immunohistochemical and immunofluorescent staining patterns for hAFP and hAlb in the multiple AA-treated rat liver that received a transplant of human bone marrow cells. (A) Representative hematoxylin-eosin (HE) staining of multiple AA-treated rat liver. Mild periportal necroinflammation and fibrosis characterized by mild portal expansion were observed at day 28. Severe septal fibrosis and swelling of hepatocytes is diffusely observed at day 56. (B) Sections of injured rat liver (day 28) from rats not given transplants were not stained at all with antibodies specific for hAFP and hAlb. Rats were treated with multiple AA and underwent transplantation with hMSCs (C) or CD34⁺ cells or non-hMSCs/CD34^- cells (D) by means of direct injection into their liver. Serial cryosections were immunostained using monoclonal antibodies specific for hAFP (Ci-x) or hAlb (Cxi-xx). (vi-x) and (xvi-xx) are magnified images of corresponding squared areas of (i-v) and (xi-xv), respectively. Similar results were obtained in 2 independent experiments. (E) Immunofluorescent staining patterns for hAlb and hAFP in rat-injected hMSCs. Rats were treated with multiple AA. Fourteen days after intrahepatic injection of hMSCs, immunofluorescent images of liver sections were obtained using a confocal laser microscope (Bio-Rad, Radiance 2100) with the Alexa 568 (Molecular Probes)-labeled anti-human AFP antibody (clone C3, 1:500; Sigma) (red) and with the Alexa 488 (Molecular Probes)-labeled anti-human Alb antibody (clone HAS-11, 1: 500; Sigma) (green). Merged immunofluorescence images of hAlb and hAFP are also presented. Scale bars represent 20 μm. Original magnifications, × 100 (A-B, E); × 200 (Ci-v, xi-xv, and D; and × 400 (Cvi-x, xvi-xx).