Confocal imaging of GFP localization and analysis of TCR rearrangement within tissue-resident cells excludes phagocytosis as major source of GFP in tissue macrophages. Confocal microscopic images of cellular GFP protein localization in sorted GFP⁺ tissue macrophages from the liver of animals that underwent transplantation and BAL (lung) samples demonstrate both (A) cellular organelle organization and (B) cytosolic GFP expression. (C) Confocal microscopic analysis of GFP expression patterns in T cells from the same samples are both localized to organelles and/or widespread throughout the cytoplasm. (D) Fraction of rearranged TCR DNA in purified T cells and macrophages from the liver and BAL of 2 animals that underwent transplantation (ZJ31 and ZK22) and 1 unmanipulated (DGMH) animal.