Cell lines of different origin (JAR (choriocarcinoma) and THP1 (monocytes, both untreated and activated by LPS/PMA)) expressing the WD40 domain of ATG16L1 fused to GST were lysed and the resulting supernatants subjected to agarose-GSH immunoprecipitation. Co-precipitating proteins were resolved by PAGE and the specific bands excised for identification using an LTQ-Orbitrap Velos device.