Open AccessA Human Blood-Brain Barrier Transcytosis Assay Reveals Antibody Transcytosis Influenced by pH-Dependent Receptor Binding
Author(s) -
Hadassah Sade,
Claudia Baumgartner,
Adrian Hugenmatter,
Ekkehard Moessner,
PerOla Freskgård,
Jens Niewoehner
Publication year - 2014
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0096340
Subject(s) - transcytosis , transferrin receptor , endosome , blood–brain barrier , receptor , antibody , transferrin , microbiology and biotechnology , biology , microscale thermophoresis , vesicular transport protein , endocytosis , biochemistry , chemistry , endocrinology , immunology , vesicle , membrane , central nervous system
We have adapted an in vitro model of the human blood-brain barrier, the immortalized human cerebral microvascular endothelial cells (hCMEC/D3), to quantitatively measure protein transcytosis. After validating the receptor-mediated transport using transferrin, the system was used to measure transcytosis rates of antibodies directed against potential brain shuttle receptors. While an antibody to the insulin-like growth factor 1 receptor (IGF1R) was exclusively recycled to the apical compartment, the fate of antibodies to the transferrin receptor (TfR) was determined by their relative affinities at extracellular and endosomal pH. An antibody with reduced affinity at pH5.5 showed significant transcytosis, while pH-independent antibodies of comparable affinities at pH 7.4 remained associated with intracellular vesicular compartments and were finally targeted for degradation.