IL-17 secretion was not enhanced by IL-23, IL-1β, or IL-6, but was enhanced by the Staphylococcus aureus-derived superantigen staphylococcal enterotoxin B. Another group, however, showed that the number of Th1 and Th17 subsets in peripheral blood from AD patients was significantly decreased, but that of the Th2 subset was similar to that of normal controls [35]. This evidence concerns the gene IL23A and Alzheimer disease.