17 Castillo-Gomez, Esther Kästner, Anne Steiner, Johann Schneider, Anja Hettling, Bilke Poggi, Giulia Ostehr, Kristin Uhr, Manfred Asif, Abdul R Matzke, Mike Schmidt, Ulrike Pfander, Viktoria Hammer, Christian Schulz, Thomas F Binder, Lutz Stöcker, Winfried Weber, Frank Ehrenreich, Hannelore AG Schneider Göttingen Annals of neurology Annals of neurology Wiley-Blackwell Hoboken, NJ 0364-5134 10.1002/ana.24545 English 144-151 1 79 Autoantibodies (AB) against N-methyl-D-aspartate receptor subunit NR1 (NMDAR1) are highly seroprevalent in health and disease. Symptomatic relevance may arise upon compromised blood-brain barrier (BBB). However, it remained unknown whether circulating NMDAR1 AB appear in the cerebrospinal fluid (CSF). Of n = 271 subjects with CSF-serum pairs, 26 were NMDAR1 AB seropositive, but only 1 was CSF positive. Contrariwise, tetanus AB (non-brain-binding) were present in serum and CSF of all subjects, with CSF levels higher upon BBB dysfunction. Translational mouse experiments proved the hypothesis that the brain acts as an 'immunoprecipitator'; simultaneous injection of NMDAR1 AB and the non-brain-binding green fluorescent protein AB resulted in high detectability of the former in brain and the latter in CSF. PUB:(DE-HGF)16, ; 0, ; Adult Animals Autoantibodies: blood Autoantibodies: cerebrospinal fluid Blood-Brain Barrier: physiopathology Brain: immunology Female Humans Male Mice Mice, Inbred C57BL Middle Aged Multiple Sclerosis: blood Multiple Sclerosis: cerebrospinal fluid Receptors, N-Methyl-D-Aspartate: immunology Seroepidemiologic Studies Autoantibodies NR1 NMDA receptor Receptors, N-Methyl-D-Aspartate Journal Article 2016 DZNE-2020-04715 2016 pmid:26505629 https://pub.dzne.de/record/138393 https://doi.org/10.1002/ana.24545