Fig. 3
From: Discovery and validation of autosomal dominant Alzheimer’s disease mutations
Amyloid-β 1–42 peptide (Aβ42) and Aβ40 in cells expressing APP, PSEN1, and PSEN2 variants of unknown pathogenicity. N2A695 cells were transfected with vectors expressing presenilin 1 or 2. Media was replaced 24 hours posttransfection and incubated for an additional 24 hours. Media were collected, and Aβ42 and Aβ40 were measured by enzyme-linked immunosorbent assay (ELISA) (pg/ml). Total intracellular protein was measured by bicinchoninic acid assay and used to normalize to ELISA Aβ values, resulting in a value represented as pg/μg (see the Methods section of text). a–c PSEN1 wild type (WT), pathogenic mutation A79V, and variants with unknown pathogenicity. a Aβ42. b Aβ40. c Aβ42/Aβ40 ratio. d–f PSEN2 WT, pathogenic mutation N141I, and variants with unknown pathogenicity. d Aβ42. e Aβ40. f Aβ42/Aβ40 ratio. g–i APP WT, pathogenic mutation KM670/671NL(Swe), and APP T719N. Graphs represent the mean (±SEM) of four replicate experiments. * p < 0.05. PSEN1 QR127G is the amino acid representation for PSEN1 c.379_382delXXXXinsG