Similarly, CCR2 deficiency in bone marrow cells in APP/PS1 mice also led to aggravation of cognitive impairment and increased levels of soluble Aβ oligomers, pointing to the role of bone marrow-derived CCR2-positive microglia in phagocytosis of soluble Aβ (Naert and Rivest 2012). This evidence concerns the gene CCR2 and Cognitive impairment.