Grevys, AlgirdasNilsen, JeannetteSand, Kine M. K.Daba, Muluneh B.Øynebråten, IngerBern, MalinMcAdam, Martin B.Foss, StianSchlothauer, TilmanMichaelsen, Terje E.Christianson, Gregory J.Roopenian, Derry C.Blumberg, RichardSandlie, IngerAndersen, Jan Terje2018-03-202018Grevys, A., J. Nilsen, K. M. K. Sand, M. B. Daba, I. Øynebråten, M. Bern, M. B. McAdam, et al. 2018. “A human endothelial cell-based recycling assay for screening of FcRn targeted molecules.” Nature Communications 9 (1): 621. doi:10.1038/s41467-018-03061-x. http://dx.doi.org/10.1038/s41467-018-03061-x.http://nrs.harvard.edu/urn-3:HUL.InstRepos:35014420Albumin and IgG have remarkably long serum half-lives due to pH-dependent FcRn-mediated cellular recycling that rescues both ligands from intracellular degradation. Furthermore, increase in half-lives of IgG and albumin-based therapeutics has the potential to improve their efficacies, but there is a great need for robust methods for screening of relative FcRn-dependent recycling ability. Here, we report on a novel human endothelial cell-based recycling assay (HERA) that can be used for such pre-clinical screening. In HERA, rescue from degradation depends on FcRn, and engineered ligands are recycled in a manner that correlates with their half-lives in human FcRn transgenic mice. Thus, HERA is a novel cellular assay that can be used to predict how FcRn-binding proteins are rescued from intracellular degradation.en-USJournal Article2018-03-2010.1038/s41467-018-03061-x