Reactive microglia induced MES 23.5 cell injury. MES 23.5 cell injury was determined by measuring TH activity in the cocultures with microglia. A, Cocultures were treated with vehicle, LPS (4 μg/ml), high-dose PD IgG (200 μg/ml), high-dose DC IgG (200 μg/ml), and high-dose DA-Q-M MES 23.5 cell membranes (150 μg/ml). B, Specificity of low-dose PD IgG (20 μg/ml) + DA-Q-M membranes (15 μg/ml) induced MES 23.5 cell injury. Column 1, Low-dose PD IgG (20 μg/ml;n = 7) + low-dose DA-Q-M MES 23.5 cell membranes (15 μg/ml). Column 2, Low-dose DC IgG (n = 8) + low-dose DA-Q-M MES 23.5 cell membranes (15 μg/ml). Dashed lines represent the mean value of TH activity in the cocultures treated with PD IgG (n = 7) or DC IgG + DA-Q-M MES 23.5 cell membranes.p < 0.05; PD IgG + DA-Q-M membranes versus DC IgG + DA-Q-M membranes. *p < 0.01 and **p < 0.005 versus control cocultures.