Immunoreactivity of Tr(DNER) antibodies. (A) Section of rat cerebellum immunostained with a serum from a patient with Tr antibodies. There is robust staining of the cytoplasm and the main dendrites of the Purkinje cells and a dot-like pattern of staining of the cerebellar molecular layer that is characteristic of Tr immunoreactivity. (B-D) Cell-based assay to confirm that Tr antibodies identify the DNER antigen. HEK293 cells transfected with DNER cDNA plasmid show intense reactivity with the human serum positive for Tr antibodies (green) and that colocalizes (yellow) with the labeling of a commercial monoclonal antibody to DNER (red).