In contrast, levels of detergent-soluble ACE2 were negatively associated with the insoluble phosphorylated form of TAR DNA-binding protein 43 (TDP-43) (which is higher in AD [15]) but positively with soluble phospho-TDP-43 C-terminal fragment migrating at approximately ~ 35 kDa (which is lower in AD [15]) and soluble tau (Fig. 3). Here, ACE2 is linked to Alzheimer disease.