Fig. 5

Enhanced chemokine expression of CCR5 on immune cells isolated from the perfused brain of mice treated with morphine, HIV-1 Tat, and S. pneumoniae (S.p) at the 5th day of post-pellet implantation. Flow cytometry profile of single-cell suspension. a Representative histograms demonstrating CCR5 expression on a distinct immune cell. Histograms demonstrating CXCR4 expression (i and ii) on CD3+ and (iii and iv) on Ly6C+ cells. Bar diagrams representing quantification of CCR5 expression on b CD3+ and c Ly6C+ as a mean fold change from the group of mice implanted with placebo pellets [basal level (dashed line)]. Error bars indicate the standard error of the mean (SEM) of six different animals from each group (n = 6). PP placebo pellet, MP morphine pellet. *P < 0.05; **P < 0.01