IL6 and Alzheimer disease: Studies have shown that IL-6, IL-8 (Proietta et al., 2014), IL-11 (Xu Y. et al., 2018), IL-12 (Ye et al., 2018), IL-16 (Fan et al., 2017) and IL-18 (Hu et al., 2019) are elevated in the serum of AD patients, and may represent biomarkers for the diagnosis of AD.