Assays

Cells were collected and lysed in urea buffer (9 M Urea, 50 mM Tris pH 8, 150 mM NaCl, 1x Roche protease inhibitor cocktail) followed by short sonification. Samples were cleared by centrifugation and protein amounts were adapted. Protein reduction was performed with dithiothreitol (DTT; 5 mM final) for 25 min at 56°C and protein alkylation by the addition of iodoacetamide (14 mM final) for 30 min at room temperature. Protein mixtures were quenched with DTT and diluted 1:5 with 1 M Tris-Hcl, pH ...

Blood samples (20 ml) from clinically affected homozygous Npc1 mutation carriers and healthy donors were collected. Negative selection of peripheral blood monocyte-derived macrophages was performed by incubating full blood for 20 min at RT with RosetteSep Human Monocyte Enrichment Cocktail (StemCell Technologies). An equal volume of washing buffer (D-PBS/2% FBS/1 mM EDTA) was added to each sample and layer of macrophages was separated from red blood cells and plasma by centrifugation on a Ficoll ...

Samples were processed and analyszed as described in Behrends et al., Nature 2010.

Anti-HA-immunoprecipitation was performed as previously described (Behrends et al, 2010; Jung et al, 2015; Jung et al, 2017; Sowa et al, 2009). Summarily, expression of TAPL-HA and coreTAPL-HA was induced by addition of 4 µg/ml doxycycline for 24 h in HeLa Flp-In T-REx cells. Parental non-transfected HeLa Flp-In T-REx cells were used as negative control. For each sample, 6.4 x 107 cells were harvested, frozen in liquid nitrogen and stored at -80 °C. Cells were lysed in 3 ml MCLB buffer (50 mM ...