C5L2 is present in neurons of control brain and neurofibrillary tangles of AD brain. Immunostaining with anti C5L2 antibody N1-23 shows labeling of a subset of neurons in frontal cortex (FC) (A) and hippocampus (B) of control cases and strong staining of tangles (arrowheads) in frontal cortex (C) and hippocampus (D) of AD cases. Scale bar: 50 um. Arrow in insert (D) shows neuropil threads. C5L2 N1-23 antibody immunostaining in hippocampus of an AD case (E) disappears after antibody preabsorption with the peptide (F). Scale bars: A,B,C,D (and insert): 50 um; E,F: 100 um. AD, Alzheimer’s disease.