CD86 and Alzheimer disease: In the anti-IgG mAb group, CD86 expression was significantly decreased (p = 0.003) in AD mice compared to non-AD mice, whereas in the anti-CTLA-4 mAb group, CD86 expression showed no significant difference between non-AD and AD mice, and CD86 expression was restored in AD mice to a similar level as non-AD mice by administration of anti-CTLA-4 mAb (Fig. 4c).