Anti-Aquaporin-1 Autoantibodies in Patients with Neuromyelitis Optica Spectrum Disorders
Figure 8
Determination of the percentage of antibodies directed against the extracellular domain of membrane-embedded AQP1.
Four anti-AQP1-positive sera were left untreated or were preincubated with increasing numbers of AQP1-GFP- (filled symbols) or EGFP-transfected (shown only for serum 3; empty triangle) HEK293 cells treated with secretin to increase surface expression of AQP1; the untreated and treated samples were tested in the usual RIPA for anti-AQP1 antibodies. The sera were also treated with AQP4-transfected HEK293 cells (shown only for serum 3; open circle). Serum 4 was also treated with an extract of AQP1-transfected HEK293 cells (open square).