Since VGlut1 puncta is increased in Arc‐C5aR1KO (compared to Arctic mice) but there is no difference in % C1q puncta, our results suggest that although C1q tagging plays a role in presynaptic pruning in this AD mouse model, the presence of C1q puncta is not sufficient to lead to ingestion of synapses. This evidence concerns the gene ARC and Alzheimer disease.