Lymphomonocytic liver infiltration in GFP LV-injected mice. (A) Histologic analysis of paraffin-embedded liver sections of the indicated mice injected 2 weeks before with CMV-GFP LV or vehicle after hematoxylin and eosin staining. Representative pictures from 3 mice analyzed per strain. Original magnification, × 200. (B) Confocal microscopy analysis of liver sections of mice injected 2 weeks before with LV particles with or without (LV-Empty) the vector genome and immunostained for GFP (green), MHCII, or CD8 (red), and DNA by TOPRO3 (blue). Representative pictures are from 3 mice analyzed per strain. Original magnification, × 400. (C) FACS analysis of liver cell suspensions obtained from LV and vehicle (PBS) injected mice at the indicated time after injection and labeled with CD4 and CD8 antibodies. The percentage of positive cells in the mononuclear cell gate (mean ± SD, n = 3) is shown.