IL6 and Alzheimer disease: Among inflammatory markers, interleukin 6 (IL-6), interleukin 1 (IL-1), cytoskeleton-associated protein 4 (CKAP4), and galectin-9 (GAL-9 or Gal-9) had received most attention as the common links between COVID-19 and AD manifestations [18] (Fig. 1).