Fig. 7

Differential surface expression of Toll-like receptors (TLRs) on distinct immune cells at the 5th day of post-pellet implantation. Histograms demonstrate mean fold change in TLR4 and TLR2 expression on the CD3+ and Ly6C+ immune cells in the CNS prefrontal cortex region of mice treated with morphine, HIV-1 Tat, and S. pneumoniae. Error bars indicate the standard error of the mean (SEM) of six different animals from each group (n = 6 mice). PP placebo pellet, MP morphine pellet. *P < 0.05; **P < 0.01