C3 and Alzheimer disease: A statistically significant increase in C3+/S100β+ cells was detected in the CA1 of 16 months old AD relative to WT (Fig. 3G, H, p=0.0001), AD/cKO relative to cKO (Fig. 3 G,H, p=0.0001) and in cortex of AD vs. WT (Fig. 3G H, p=0.0001) and AD/cKO vs. cKO (Fig. 3 G, H, p<0.0001).