In situ multiplex immunofluorescence analysis of the inflammatory burden in kidney allograft rejection: A new tool to characterize the alloimmune response

Abstract

The exact composition of leukocyte infiltration during kidney allograft rejection is difficult to comprehend and visualize on the same biopsy slide. Using an innovative technology of multiplex immunofluorescence (mIF), we were able to detect simultaneously NK cells, macrophages, and T cells and to determine their intra- or extravascular localization using an endothelial marker. Twenty antibody-mediated rejection (ABMR), 20 T cell–mediated rejection (TCMR), and five normal biopsies were labeled, with automatic leukocyte quantification and localization. This method was compared to a classic NKp46 immunohistochemistry (IHC) with manual quantification and to mRNA quantification. mIF automatic quantification was strongly correlated to IHC (r =.91, P.46, P