The online version of this article (doi:10.1186/s12974-017-0842-5) contains supplementary material, which is available to authorized users.
Atypical antipsychotic agents, such as clozapine, are used for treating psychosis and depression and have recently been found to modulate neuroinflammation. We have shown previously that treatment of mice with the atypical antipsychotic agents, clozapine or risperidone, attenuates disease severity in experimental autoimmune encephalomyelitis (EAE); however, the mechanism by which they are protective is unknown. In this study, we investigated the effects of clozapine on CD4+ T cell responses and found that clozapine did not significantly affect the expansion of myelin-specific T cells, their differentiation into pathogenic subsets, or their encephalitogenic capacity to induce EAE. Interestingly, although clozapine enhanced differentiation of regulatory T (Treg) cells, in vivo neutralization of Tregs indicated that Tregs were not responsible for the protective effects of clozapine during the induction and effector phase of EAE. Taken together, our studies indicate that clozapine does not mediate its protective effects by directly altering CD4 T cells.
Additional file 1: Gating strategy for identifying dopaminergic and adrenergic receptors on T cells. Spleens were isolated from mice 15 d.p.i and analyzed by flow cytometry for dopamine and adrenergic receptor expression. A gating strategy for identifying CD4 (bottom left), CD8 (bottom center), and Tregs (bottom right). Representative histograms for expression of B dopamine D1 receptor (D1R) and C dopamine D2 receptor (D2R) on CD4 T cells. Graphical representation of receptor expression on different T cell subsets of D D1R and E D2R. Shown are means and SEM of individual mice from one experiment (n = 5 mice in each group). Statistical analyses between healthy control and EAE mice conducted by two-way ANOVA. (TIF 17402 kb)12974_2017_842_MOESM1_ESM.tif
Additional file 2: CD25 neutralization 0, 10, and 17 d.p.i Mice were injected with 200 μg/mouse anti-CD25 (PC61) antibody at −3, 7, and 14 d.p.i CD25 neutralization was assessed by flow cytometry using Alexa Fluor 488 conjugated anti CD25 (PC61) at days A 0, B 10, and C 17. CD4+ T cells were identified using the gating strategy described in Additional file 3. (TIF 12283 kb)
Additional file 3: Gating strategy to identify CD4+ T cells and 2D2 MOG35-55 TCR CD4+. Single cells were gated using FSC-A and FSC-H. Cells of interest were gated using FSC-A and SSC-A. Lymphocytes were identified by CD11b− and CD3+ expression. CD4 T cells were distinguished using CD8− and CD4+ expression. Tregs were identified as CD25+ and Foxp3+. Th17 cells were identified as ROR\( \gamma \)T+. (TIF 14847 kb)12974_2017_842_MOESM3_ESM.tif
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- Amelioration of experimental autoimmune encephalomyelitis by clozapine is not associated with defective CD4 T cell responses
Anne Camille La Flamme
- BioMed Central