The relation of different inflammatory cell types to the various parenchymal components of rejecting kidney allografts.

Histochemical and immunoperoxidase techniques were used to characterize the spatial relationships of various inflammatory cell types to the different transplant structures in human renal allograft rejection. T lymphocytes were identified by acid alpha-naphthyl acetate esterase (ANAE) staining, plasma cells by intracytoplasmic immunoglobulin, mononuclear phagocytes by intracytoplasmic 'dispersed' ANAE reaction and/or lysozyme staining and granulocytes by intracellular lactoferrin. In the two cases of acute rejection the infiltrate around the blood vessels consisted mainly of lymphocytes, whereas the infiltrate around the tubules and within the glomerular tufts consisted mainly of mononuclear phagocytes. In acute rejection only a few plasma cells and granulocytes were seen. In the single case of chronic rejection studied, the lymphocytes were no longer concentrated exclusively around the blood vessels, but diffusely distributed throughout the kidney parenchyma. The different distribution of various inflammatory cells may reflect differences in the functions of these cell types in graft destruction.