Although the number of Iba-1+ cells (a marker for microglia) in the OB did not show a difference between the two groups (Figure 2D–F), the number of CD68+ cells (a marker for activated microglia) and the ratio of CD68+ cells to Iba-1+ cells were increased in the PD group (Figure 2D,E,G,H). Here, AIF1 is linked to Parkinson disease.