Figure 10.

Delta-9-tetrahydrocannabinol (Δ⁹-THC) administration increased the percentage of CD163 expressing anti-inflammatory macrophages in intestine after SIV infection. To quantify CD163⁺ anti-inflammatory macrophages, cells were gated first on singlets, CD45⁺ cells, followed by live cells and then on CD3⁻CD14⁻⁻ cell subsets to quantify CD163⁺ cells (A). Frequencies of CD163⁺ cells at preinfection and 180 days post-infection are shown from a representative THC/SIV and VEH/SIV rhesus macaque (A). The percentages of the total gated population are shown in each box of the plot. Note that the THC/SIV infected animal had significantly higher CD163⁺ cells compared to VEH/SIV infected animal at 180 days post-SIV infection (A). Open red circles- VEH/SIV, Open blue squares- THC/SIV. Horizontal red and blue lines with P-values denote comparisons between time points within the VEH/SIV and THC/SIV groups, respectively. Left black brackets with an asterisk indicate statistical significance (p = 0.0286) between the VEH/SIV and THC/SIV groups for a given time point. Connecting blue and red lines (B) denote mean values of the respective population in the THC/SIV and VEH/SIV groups, respectively. Flow cytometry analysis to determine the effect of Δ⁹-THC on CD163 expression in intestinal macrophages of SIV-infected rhesus macaques was performed once with four individual animals as biological replicates per group. Flow cytometry data were analyzed using linear mixed models with immune-marker outcomes being dependent variables, and treatment status (VEH vs. Δ⁹-THC) and days since the start of treatment (0, 14, 150, 180) being dependent variables with fixed effects. Differences between two time points were analyzed using the Mann-Whitney U-test employing the Prism v5 software (GraphPad software). A p-value of ≤0.05 was considered significant.