Figure 9.

Short M-CSF treatment increases monocyte frequency in WT and APP_Swe/PS1 mice in a CCR2-dependent manner. Monocyte frequency was determined by FACS analysis within the population of CD45⁺ cells using the CD11b and CD115 markers in WT, CCR2^−/−, APP_Swe/PS1, and APP_Swe/PS1/CCR2^−/− mice. Mice received saline or M-CSF treatment during 4 days (40 μg/Kg/day) at the age of 4 months and blood samples were analyzed 24 h after the last injection. M-CSF treatment increased the frequency of monocytes (CD11b⁺CD115⁺) in both WT and APP_Swe/PS1 groups of mice. In contrast, monocyte frequency remained very low in CCR2^−/− and APP_Swe/PS1/CCR2^−/− mice treated or not with the cytokine. Results are expressed as the Mean ± SEM; n = 5–8; Student's t-test; ^*p < 0.05; ^**p < 0.01; ^* vs. saline treatment in the same genotype.