(A) Formic acid (FA)-soluble Aβ42 levels are decreased in carriers of the rs3865444 minor (T) allele. ELISA analysis of Aβ40 and Aβ42 in FA-soluble fractions isolated from the frontal cortex of AD cases of the indicated genotypes (**p < 0.01, Student’s t test). Data are represented as mean ± SEM.
(B) The protective rs3865444 (T) allele is associated with decreased levels of both FA-soluble Aβ42 and TBS-soluble Aβ40 in AD cases (n = 25 AD cases, n = 15 controls, general linear regression model, p < 0.05 was considered statistically significant).
(C) The numbers of CD33-immunoreactive microglia positively correlate with the FA-soluble Aβ42 levels in AD cases (n = 25; r = 0.446; p = 0.02, Spearman’s correlation test).
(D) The numbers of CD33-positive microglia positively correlate with amyloid plaque burden in AD brain (n = 25; r = 0.471; p = 0.017; Spearman’s correlation test). See also Figure S3.