Antiallodynic Effects of Cannabinoid Receptor 2 (CB₂R) Agonists on Retrovirus Infection-Induced Neuropathic Pain

Figure 4

Effects of CB₂R agonists on lymphocyte infiltration into the DRG. After LP-BM5 infection, synthetic CB₂R ligands were injected (5 mg/kg, i.p.) twice/wk starting at 5 or 6 wk (HU308) p.i. At 12 wk p.i., DRG were dissected and mononuclear cells from six ganglia (L3–L5) per mouse were isolated using nonenzymatic dissociation. Mononuclear cells were then labeled with Abs specific for CD45, CD4, and CD8 for analysis by flow cytometry. (a) Representative contour plots show percentages of CD4⁺ and CD8⁺ T-lymphocytes within uninfected (UI), infected (IF), and infected (IF + indicated CB₂R ligand), agonist-treated DRG. (b) Frequency and number of CD4⁺ T-cells infiltrating into DRG of animals belonging to the indicated treatment groups. (c) Frequency and number of CD8⁺ T-cells infiltrating into DRG of animals belonging to the indicated treatment groups. Pooled data present absolute numbers (mean ± SE) of CD4⁺ and CD8⁺ T-cells from two independent experiments using 4–6 animals per group. ; .

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