Fig. 1. Purified GCase-BS molecules are fully functional.

a Schematic of GCase-BS depicting different moieties: GCase domain II is shown in red, domain III in green, domain I is hidden behind domain III in this view²³. The human IgG1 Fc part of the Brain Shuttle is shown in grey, the TfR binding Fab is depicted in purple. b Assessment and specificity of murine TfR binding of the various GCase(-BS) molecules by FACS analysis of mTfR-expressing cells. Representative data of 2 biological replicates. c Assessment and specificity of human TfR binding of the various GCase(-BS) molecules by FACS analysis of hTfR-expressing cells. Representative data of 2 biological replicates. d Enzymatic activity of various GCase(-BS) molecules at an enzyme concentration of 25 nM (Michaelis-Menten kinetics). Activity was measured over time using different concentrations of resorufin-β-glucopyranoside. n = 3 independent measurements. e Enzymatic activity and IgG levels measured for both mGCase-mBS and hGCase-hBS after 15 min incubation in 10% mouse plasma. n = 2 independent measurements. Source data are provided as a Source Data file.