-antitrypsin (A1AT) treatment reduces Aβ oligomer-induced cytotoxicity on primary microglial cells. A. Primary microglial cells were treated with 2 μM Aβ1-42 oligomers and/or different concentrations of A1AT for 24 hours. An MTT-assay was performed to detect the cell viability. Viability of untreated cells was referred to as 100% viability. Means and standard deviations of the mean of three independent experiments are shown (**P value ≤ 0.01, ***P value ≤ 0.001, n.s., not significant). B. 58 μM Aβ preparations were oligomerized and the effect of A1AT on the oligomerization process was assessed by western blotting with the monoclonal Aβ antibody 6E10. One representative western blot out of three is shown. C. Uptake of Aβ1-42 oligomers under the influence of different concentrations of A1AT was investigated by western blotting. Cells were treated with 2 μM Aβ and different concentrations of A1AT (4 mg/ml to 0.1 mg/ml) for three hours. We used the monoclonal antibody 6E10 to detect Aβ and a polyclonal antibody to detect A1AT in cell lysates. GAPDH was used as loading control. One representative western blot out of three is shown.