BACE1 and Alzheimer disease: Many PLA signals were generated when ADAM10 and BACE1 were probed against both synaptophysin (Fig. 4a–d) and PSD-95 (Fig. 4e–h) in AD or control brain hippocampus, whereas only limited number of signals were detected in the negative control samples where the primary antibodies had been omitted (Fig. 4i–j).